From 1d4d76a9971fbc358875d95543d6aa7d8e727ba4 Mon Sep 17 00:00:00 2001 Message-Id: <1d4d76a9971fbc358875d95543d6aa7d8e727ba4.1606170834.git.m.a.young@durham.ac.uk> From: Michael Young Date: Sat, 21 Nov 2020 20:28:54 +0000 Subject: [XEN PATCH 1/2] import zstd decompress code from fedora kernel kernel-5.9.8-200.fc33 --- xen/common/decompress_unzstd.c | 345 ++++ xen/common/xxhash.c | 500 ++++++ xen/common/zstd/bitstream.h | 379 +++++ xen/common/zstd/decompress.c | 2531 ++++++++++++++++++++++++++++++ xen/common/zstd/entropy_common.c | 243 +++ xen/common/zstd/error_private.h | 53 + xen/common/zstd/fse.h | 575 +++++++ xen/common/zstd/fse_decompress.c | 325 ++++ xen/common/zstd/huf.h | 212 +++ xen/common/zstd/huf_decompress.c | 960 +++++++++++ xen/common/zstd/mem.h | 151 ++ xen/common/zstd/zstd_common.c | 75 + xen/common/zstd/zstd_internal.h | 273 ++++ xen/common/zstd/zstd_opt.h | 1014 ++++++++++++ xen/include/xen/xxhash.h | 259 +++ xen/include/xen/zstd.h | 1157 ++++++++++++++ 16 files changed, 9052 insertions(+) create mode 100644 xen/common/decompress_unzstd.c create mode 100644 xen/common/xxhash.c create mode 100644 xen/common/zstd/bitstream.h create mode 100644 xen/common/zstd/decompress.c create mode 100644 xen/common/zstd/entropy_common.c create mode 100644 xen/common/zstd/error_private.h create mode 100644 xen/common/zstd/fse.h create mode 100644 xen/common/zstd/fse_decompress.c create mode 100644 xen/common/zstd/huf.h create mode 100644 xen/common/zstd/huf_decompress.c create mode 100644 xen/common/zstd/mem.h create mode 100644 xen/common/zstd/zstd_common.c create mode 100644 xen/common/zstd/zstd_internal.h create mode 100644 xen/common/zstd/zstd_opt.h create mode 100644 xen/include/xen/xxhash.h create mode 100644 xen/include/xen/zstd.h diff --git a/xen/common/decompress_unzstd.c b/xen/common/decompress_unzstd.c new file mode 100644 index 0000000000..0ad2c15479 --- /dev/null +++ b/xen/common/decompress_unzstd.c @@ -0,0 +1,345 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Important notes about in-place decompression + * + * At least on x86, the kernel is decompressed in place: the compressed data + * is placed to the end of the output buffer, and the decompressor overwrites + * most of the compressed data. There must be enough safety margin to + * guarantee that the write position is always behind the read position. + * + * The safety margin for ZSTD with a 128 KB block size is calculated below. + * Note that the margin with ZSTD is bigger than with GZIP or XZ! + * + * The worst case for in-place decompression is that the beginning of + * the file is compressed extremely well, and the rest of the file is + * uncompressible. Thus, we must look for worst-case expansion when the + * compressor is encoding uncompressible data. + * + * The structure of the .zst file in case of a compresed kernel is as follows. + * Maximum sizes (as bytes) of the fields are in parenthesis. + * + * Frame Header: (18) + * Blocks: (N) + * Checksum: (4) + * + * The frame header and checksum overhead is at most 22 bytes. + * + * ZSTD stores the data in blocks. Each block has a header whose size is + * a 3 bytes. After the block header, there is up to 128 KB of payload. + * The maximum uncompressed size of the payload is 128 KB. The minimum + * uncompressed size of the payload is never less than the payload size + * (excluding the block header). + * + * The assumption, that the uncompressed size of the payload is never + * smaller than the payload itself, is valid only when talking about + * the payload as a whole. It is possible that the payload has parts where + * the decompressor consumes more input than it produces output. Calculating + * the worst case for this would be tricky. Instead of trying to do that, + * let's simply make sure that the decompressor never overwrites any bytes + * of the payload which it is currently reading. + * + * Now we have enough information to calculate the safety margin. We need + * - 22 bytes for the .zst file format headers; + * - 3 bytes per every 128 KiB of uncompressed size (one block header per + * block); and + * - 128 KiB (biggest possible zstd block size) to make sure that the + * decompressor never overwrites anything from the block it is currently + * reading. + * + * We get the following formula: + * + * safety_margin = 22 + uncompressed_size * 3 / 131072 + 131072 + * <= 22 + (uncompressed_size >> 15) + 131072 + */ + +/* + * Preboot environments #include "path/to/decompress_unzstd.c". + * All of the source files we depend on must be #included. + * zstd's only source dependeny is xxhash, which has no source + * dependencies. + * + * When UNZSTD_PREBOOT is defined we declare __decompress(), which is + * used for kernel decompression, instead of unzstd(). + * + * Define __DISABLE_EXPORTS in preboot environments to prevent symbols + * from xxhash and zstd from being exported by the EXPORT_SYMBOL macro. + */ +#ifdef STATIC +# define UNZSTD_PREBOOT +# include "xxhash.c" +# include "zstd/entropy_common.c" +# include "zstd/fse_decompress.c" +# include "zstd/huf_decompress.c" +# include "zstd/zstd_common.c" +# include "zstd/decompress.c" +#endif + +#include +#include +#include + +/* 128MB is the maximum window size supported by zstd. */ +#define ZSTD_WINDOWSIZE_MAX (1 << ZSTD_WINDOWLOG_MAX) +/* + * Size of the input and output buffers in multi-call mode. + * Pick a larger size because it isn't used during kernel decompression, + * since that is single pass, and we have to allocate a large buffer for + * zstd's window anyway. The larger size speeds up initramfs decompression. + */ +#define ZSTD_IOBUF_SIZE (1 << 17) + +static int INIT handle_zstd_error(size_t ret, void (*error)(char *x)) +{ + const int err = ZSTD_getErrorCode(ret); + + if (!ZSTD_isError(ret)) + return 0; + + switch (err) { + case ZSTD_error_memory_allocation: + error("ZSTD decompressor ran out of memory"); + break; + case ZSTD_error_prefix_unknown: + error("Input is not in the ZSTD format (wrong magic bytes)"); + break; + case ZSTD_error_dstSize_tooSmall: + case ZSTD_error_corruption_detected: + case ZSTD_error_checksum_wrong: + error("ZSTD-compressed data is corrupt"); + break; + default: + error("ZSTD-compressed data is probably corrupt"); + break; + } + return -1; +} + +/* + * Handle the case where we have the entire input and output in one segment. + * We can allocate less memory (no circular buffer for the sliding window), + * and avoid some memcpy() calls. + */ +static int INIT decompress_single(const u8 *in_buf, long in_len, u8 *out_buf, + long out_len, long *in_pos, + void (*error)(char *x)) +{ + const size_t wksp_size = ZSTD_DCtxWorkspaceBound(); + void *wksp = large_malloc(wksp_size); + ZSTD_DCtx *dctx = ZSTD_initDCtx(wksp, wksp_size); + int err; + size_t ret; + + if (dctx == NULL) { + error("Out of memory while allocating ZSTD_DCtx"); + err = -1; + goto out; + } + /* + * Find out how large the frame actually is, there may be junk at + * the end of the frame that ZSTD_decompressDCtx() can't handle. + */ + ret = ZSTD_findFrameCompressedSize(in_buf, in_len); + err = handle_zstd_error(ret, error); + if (err) + goto out; + in_len = (long)ret; + + ret = ZSTD_decompressDCtx(dctx, out_buf, out_len, in_buf, in_len); + err = handle_zstd_error(ret, error); + if (err) + goto out; + + if (in_pos != NULL) + *in_pos = in_len; + + err = 0; +out: + if (wksp != NULL) + large_free(wksp); + return err; +} + +static int INIT __unzstd(unsigned char *in_buf, long in_len, + long (*fill)(void*, unsigned long), + long (*flush)(void*, unsigned long), + unsigned char *out_buf, long out_len, + long *in_pos, + void (*error)(char *x)) +{ + ZSTD_inBuffer in; + ZSTD_outBuffer out; + ZSTD_frameParams params; + void *in_allocated = NULL; + void *out_allocated = NULL; + void *wksp = NULL; + size_t wksp_size; + ZSTD_DStream *dstream; + int err; + size_t ret; + + if (out_len == 0) + out_len = LONG_MAX; /* no limit */ + + if (fill == NULL && flush == NULL) + /* + * We can decompress faster and with less memory when we have a + * single chunk. + */ + return decompress_single(in_buf, in_len, out_buf, out_len, + in_pos, error); + + /* + * If in_buf is not provided, we must be using fill(), so allocate + * a large enough buffer. If it is provided, it must be at least + * ZSTD_IOBUF_SIZE large. + */ + if (in_buf == NULL) { + in_allocated = large_malloc(ZSTD_IOBUF_SIZE); + if (in_allocated == NULL) { + error("Out of memory while allocating input buffer"); + err = -1; + goto out; + } + in_buf = in_allocated; + in_len = 0; + } + /* Read the first chunk, since we need to decode the frame header. */ + if (fill != NULL) + in_len = fill(in_buf, ZSTD_IOBUF_SIZE); + if (in_len < 0) { + error("ZSTD-compressed data is truncated"); + err = -1; + goto out; + } + /* Set the first non-empty input buffer. */ + in.src = in_buf; + in.pos = 0; + in.size = in_len; + /* Allocate the output buffer if we are using flush(). */ + if (flush != NULL) { + out_allocated = large_malloc(ZSTD_IOBUF_SIZE); + if (out_allocated == NULL) { + error("Out of memory while allocating output buffer"); + err = -1; + goto out; + } + out_buf = out_allocated; + out_len = ZSTD_IOBUF_SIZE; + } + /* Set the output buffer. */ + out.dst = out_buf; + out.pos = 0; + out.size = out_len; + + /* + * We need to know the window size to allocate the ZSTD_DStream. + * Since we are streaming, we need to allocate a buffer for the sliding + * window. The window size varies from 1 KB to ZSTD_WINDOWSIZE_MAX + * (8 MB), so it is important to use the actual value so as not to + * waste memory when it is smaller. + */ + ret = ZSTD_getFrameParams(¶ms, in.src, in.size); + err = handle_zstd_error(ret, error); + if (err) + goto out; + if (ret != 0) { + error("ZSTD-compressed data has an incomplete frame header"); + err = -1; + goto out; + } + if (params.windowSize > ZSTD_WINDOWSIZE_MAX) { + error("ZSTD-compressed data has too large a window size"); + err = -1; + goto out; + } + + /* + * Allocate the ZSTD_DStream now that we know how much memory is + * required. + */ + wksp_size = ZSTD_DStreamWorkspaceBound(params.windowSize); + wksp = large_malloc(wksp_size); + dstream = ZSTD_initDStream(params.windowSize, wksp, wksp_size); + if (dstream == NULL) { + error("Out of memory while allocating ZSTD_DStream"); + err = -1; + goto out; + } + + /* + * Decompression loop: + * Read more data if necessary (error if no more data can be read). + * Call the decompression function, which returns 0 when finished. + * Flush any data produced if using flush(). + */ + if (in_pos != NULL) + *in_pos = 0; + do { + /* + * If we need to reload data, either we have fill() and can + * try to get more data, or we don't and the input is truncated. + */ + if (in.pos == in.size) { + if (in_pos != NULL) + *in_pos += in.pos; + in_len = fill ? fill(in_buf, ZSTD_IOBUF_SIZE) : -1; + if (in_len < 0) { + error("ZSTD-compressed data is truncated"); + err = -1; + goto out; + } + in.pos = 0; + in.size = in_len; + } + /* Returns zero when the frame is complete. */ + ret = ZSTD_decompressStream(dstream, &out, &in); + err = handle_zstd_error(ret, error); + if (err) + goto out; + /* Flush all of the data produced if using flush(). */ + if (flush != NULL && out.pos > 0) { + if (out.pos != flush(out.dst, out.pos)) { + error("Failed to flush()"); + err = -1; + goto out; + } + out.pos = 0; + } + } while (ret != 0); + + if (in_pos != NULL) + *in_pos += in.pos; + + err = 0; +out: + if (in_allocated != NULL) + large_free(in_allocated); + if (out_allocated != NULL) + large_free(out_allocated); + if (wksp != NULL) + large_free(wksp); + return err; +} + +#ifndef UNZSTD_PREBOOT +STATIC int INIT unzstd(unsigned char *buf, long len, + long (*fill)(void*, unsigned long), + long (*flush)(void*, unsigned long), + unsigned char *out_buf, + long *pos, + void (*error)(char *x)) +{ + return __unzstd(buf, len, fill, flush, out_buf, 0, pos, error); +} +#else +STATIC int INIT __decompress(unsigned char *buf, long len, + long (*fill)(void*, unsigned long), + long (*flush)(void*, unsigned long), + unsigned char *out_buf, long out_len, + long *pos, + void (*error)(char *x)) +{ + return __unzstd(buf, len, fill, flush, out_buf, out_len, pos, error); +} +#endif diff --git a/xen/common/xxhash.c b/xen/common/xxhash.c new file mode 100644 index 0000000000..d5bb9ff106 --- /dev/null +++ b/xen/common/xxhash.c @@ -0,0 +1,500 @@ +/* + * xxHash - Extremely Fast Hash algorithm + * Copyright (C) 2012-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at: + * - xxHash homepage: https://cyan4973.github.io/xxHash/ + * - xxHash source repository: https://github.com/Cyan4973/xxHash + */ + +#include +#include +#include +#include +#include +#include +#include + +/*-************************************* + * Macros + **************************************/ +#define xxh_rotl32(x, r) ((x << r) | (x >> (32 - r))) +#define xxh_rotl64(x, r) ((x << r) | (x >> (64 - r))) + +#ifdef __LITTLE_ENDIAN +# define XXH_CPU_LITTLE_ENDIAN 1 +#else +# define XXH_CPU_LITTLE_ENDIAN 0 +#endif + +/*-************************************* + * Constants + **************************************/ +static const uint32_t PRIME32_1 = 2654435761U; +static const uint32_t PRIME32_2 = 2246822519U; +static const uint32_t PRIME32_3 = 3266489917U; +static const uint32_t PRIME32_4 = 668265263U; +static const uint32_t PRIME32_5 = 374761393U; + +static const uint64_t PRIME64_1 = 11400714785074694791ULL; +static const uint64_t PRIME64_2 = 14029467366897019727ULL; +static const uint64_t PRIME64_3 = 1609587929392839161ULL; +static const uint64_t PRIME64_4 = 9650029242287828579ULL; +static const uint64_t PRIME64_5 = 2870177450012600261ULL; + +/*-************************** + * Utils + ***************************/ +void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src) +{ + memcpy(dst, src, sizeof(*dst)); +} +EXPORT_SYMBOL(xxh32_copy_state); + +void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src) +{ + memcpy(dst, src, sizeof(*dst)); +} +EXPORT_SYMBOL(xxh64_copy_state); + +/*-*************************** + * Simple Hash Functions + ****************************/ +static uint32_t xxh32_round(uint32_t seed, const uint32_t input) +{ + seed += input * PRIME32_2; + seed = xxh_rotl32(seed, 13); + seed *= PRIME32_1; + return seed; +} + +uint32_t xxh32(const void *input, const size_t len, const uint32_t seed) +{ + const uint8_t *p = (const uint8_t *)input; + const uint8_t *b_end = p + len; + uint32_t h32; + + if (len >= 16) { + const uint8_t *const limit = b_end - 16; + uint32_t v1 = seed + PRIME32_1 + PRIME32_2; + uint32_t v2 = seed + PRIME32_2; + uint32_t v3 = seed + 0; + uint32_t v4 = seed - PRIME32_1; + + do { + v1 = xxh32_round(v1, get_unaligned_le32(p)); + p += 4; + v2 = xxh32_round(v2, get_unaligned_le32(p)); + p += 4; + v3 = xxh32_round(v3, get_unaligned_le32(p)); + p += 4; + v4 = xxh32_round(v4, get_unaligned_le32(p)); + p += 4; + } while (p <= limit); + + h32 = xxh_rotl32(v1, 1) + xxh_rotl32(v2, 7) + + xxh_rotl32(v3, 12) + xxh_rotl32(v4, 18); + } else { + h32 = seed + PRIME32_5; + } + + h32 += (uint32_t)len; + + while (p + 4 <= b_end) { + h32 += get_unaligned_le32(p) * PRIME32_3; + h32 = xxh_rotl32(h32, 17) * PRIME32_4; + p += 4; + } + + while (p < b_end) { + h32 += (*p) * PRIME32_5; + h32 = xxh_rotl32(h32, 11) * PRIME32_1; + p++; + } + + h32 ^= h32 >> 15; + h32 *= PRIME32_2; + h32 ^= h32 >> 13; + h32 *= PRIME32_3; + h32 ^= h32 >> 16; + + return h32; +} +EXPORT_SYMBOL(xxh32); + +static uint64_t xxh64_round(uint64_t acc, const uint64_t input) +{ + acc += input * PRIME64_2; + acc = xxh_rotl64(acc, 31); + acc *= PRIME64_1; + return acc; +} + +static uint64_t xxh64_merge_round(uint64_t acc, uint64_t val) +{ + val = xxh64_round(0, val); + acc ^= val; + acc = acc * PRIME64_1 + PRIME64_4; + return acc; +} + +uint64_t xxh64(const void *input, const size_t len, const uint64_t seed) +{ + const uint8_t *p = (const uint8_t *)input; + const uint8_t *const b_end = p + len; + uint64_t h64; + + if (len >= 32) { + const uint8_t *const limit = b_end - 32; + uint64_t v1 = seed + PRIME64_1 + PRIME64_2; + uint64_t v2 = seed + PRIME64_2; + uint64_t v3 = seed + 0; + uint64_t v4 = seed - PRIME64_1; + + do { + v1 = xxh64_round(v1, get_unaligned_le64(p)); + p += 8; + v2 = xxh64_round(v2, get_unaligned_le64(p)); + p += 8; + v3 = xxh64_round(v3, get_unaligned_le64(p)); + p += 8; + v4 = xxh64_round(v4, get_unaligned_le64(p)); + p += 8; + } while (p <= limit); + + h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) + + xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18); + h64 = xxh64_merge_round(h64, v1); + h64 = xxh64_merge_round(h64, v2); + h64 = xxh64_merge_round(h64, v3); + h64 = xxh64_merge_round(h64, v4); + + } else { + h64 = seed + PRIME64_5; + } + + h64 += (uint64_t)len; + + while (p + 8 <= b_end) { + const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p)); + + h64 ^= k1; + h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4; + p += 8; + } + + if (p + 4 <= b_end) { + h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1; + h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; + p += 4; + } + + while (p < b_end) { + h64 ^= (*p) * PRIME64_5; + h64 = xxh_rotl64(h64, 11) * PRIME64_1; + p++; + } + + h64 ^= h64 >> 33; + h64 *= PRIME64_2; + h64 ^= h64 >> 29; + h64 *= PRIME64_3; + h64 ^= h64 >> 32; + + return h64; +} +EXPORT_SYMBOL(xxh64); + +/*-************************************************** + * Advanced Hash Functions + ***************************************************/ +void xxh32_reset(struct xxh32_state *statePtr, const uint32_t seed) +{ + /* use a local state for memcpy() to avoid strict-aliasing warnings */ + struct xxh32_state state; + + memset(&state, 0, sizeof(state)); + state.v1 = seed + PRIME32_1 + PRIME32_2; + state.v2 = seed + PRIME32_2; + state.v3 = seed + 0; + state.v4 = seed - PRIME32_1; + memcpy(statePtr, &state, sizeof(state)); +} +EXPORT_SYMBOL(xxh32_reset); + +void xxh64_reset(struct xxh64_state *statePtr, const uint64_t seed) +{ + /* use a local state for memcpy() to avoid strict-aliasing warnings */ + struct xxh64_state state; + + memset(&state, 0, sizeof(state)); + state.v1 = seed + PRIME64_1 + PRIME64_2; + state.v2 = seed + PRIME64_2; + state.v3 = seed + 0; + state.v4 = seed - PRIME64_1; + memcpy(statePtr, &state, sizeof(state)); +} +EXPORT_SYMBOL(xxh64_reset); + +int xxh32_update(struct xxh32_state *state, const void *input, const size_t len) +{ + const uint8_t *p = (const uint8_t *)input; + const uint8_t *const b_end = p + len; + + if (input == NULL) + return -EINVAL; + + state->total_len_32 += (uint32_t)len; + state->large_len |= (len >= 16) | (state->total_len_32 >= 16); + + if (state->memsize + len < 16) { /* fill in tmp buffer */ + memcpy((uint8_t *)(state->mem32) + state->memsize, input, len); + state->memsize += (uint32_t)len; + return 0; + } + + if (state->memsize) { /* some data left from previous update */ + const uint32_t *p32 = state->mem32; + + memcpy((uint8_t *)(state->mem32) + state->memsize, input, + 16 - state->memsize); + + state->v1 = xxh32_round(state->v1, get_unaligned_le32(p32)); + p32++; + state->v2 = xxh32_round(state->v2, get_unaligned_le32(p32)); + p32++; + state->v3 = xxh32_round(state->v3, get_unaligned_le32(p32)); + p32++; + state->v4 = xxh32_round(state->v4, get_unaligned_le32(p32)); + p32++; + + p += 16-state->memsize; + state->memsize = 0; + } + + if (p <= b_end - 16) { + const uint8_t *const limit = b_end - 16; + uint32_t v1 = state->v1; + uint32_t v2 = state->v2; + uint32_t v3 = state->v3; + uint32_t v4 = state->v4; + + do { + v1 = xxh32_round(v1, get_unaligned_le32(p)); + p += 4; + v2 = xxh32_round(v2, get_unaligned_le32(p)); + p += 4; + v3 = xxh32_round(v3, get_unaligned_le32(p)); + p += 4; + v4 = xxh32_round(v4, get_unaligned_le32(p)); + p += 4; + } while (p <= limit); + + state->v1 = v1; + state->v2 = v2; + state->v3 = v3; + state->v4 = v4; + } + + if (p < b_end) { + memcpy(state->mem32, p, (size_t)(b_end-p)); + state->memsize = (uint32_t)(b_end-p); + } + + return 0; +} +EXPORT_SYMBOL(xxh32_update); + +uint32_t xxh32_digest(const struct xxh32_state *state) +{ + const uint8_t *p = (const uint8_t *)state->mem32; + const uint8_t *const b_end = (const uint8_t *)(state->mem32) + + state->memsize; + uint32_t h32; + + if (state->large_len) { + h32 = xxh_rotl32(state->v1, 1) + xxh_rotl32(state->v2, 7) + + xxh_rotl32(state->v3, 12) + xxh_rotl32(state->v4, 18); + } else { + h32 = state->v3 /* == seed */ + PRIME32_5; + } + + h32 += state->total_len_32; + + while (p + 4 <= b_end) { + h32 += get_unaligned_le32(p) * PRIME32_3; + h32 = xxh_rotl32(h32, 17) * PRIME32_4; + p += 4; + } + + while (p < b_end) { + h32 += (*p) * PRIME32_5; + h32 = xxh_rotl32(h32, 11) * PRIME32_1; + p++; + } + + h32 ^= h32 >> 15; + h32 *= PRIME32_2; + h32 ^= h32 >> 13; + h32 *= PRIME32_3; + h32 ^= h32 >> 16; + + return h32; +} +EXPORT_SYMBOL(xxh32_digest); + +int xxh64_update(struct xxh64_state *state, const void *input, const size_t len) +{ + const uint8_t *p = (const uint8_t *)input; + const uint8_t *const b_end = p + len; + + if (input == NULL) + return -EINVAL; + + state->total_len += len; + + if (state->memsize + len < 32) { /* fill in tmp buffer */ + memcpy(((uint8_t *)state->mem64) + state->memsize, input, len); + state->memsize += (uint32_t)len; + return 0; + } + + if (state->memsize) { /* tmp buffer is full */ + uint64_t *p64 = state->mem64; + + memcpy(((uint8_t *)p64) + state->memsize, input, + 32 - state->memsize); + + state->v1 = xxh64_round(state->v1, get_unaligned_le64(p64)); + p64++; + state->v2 = xxh64_round(state->v2, get_unaligned_le64(p64)); + p64++; + state->v3 = xxh64_round(state->v3, get_unaligned_le64(p64)); + p64++; + state->v4 = xxh64_round(state->v4, get_unaligned_le64(p64)); + + p += 32 - state->memsize; + state->memsize = 0; + } + + if (p + 32 <= b_end) { + const uint8_t *const limit = b_end - 32; + uint64_t v1 = state->v1; + uint64_t v2 = state->v2; + uint64_t v3 = state->v3; + uint64_t v4 = state->v4; + + do { + v1 = xxh64_round(v1, get_unaligned_le64(p)); + p += 8; + v2 = xxh64_round(v2, get_unaligned_le64(p)); + p += 8; + v3 = xxh64_round(v3, get_unaligned_le64(p)); + p += 8; + v4 = xxh64_round(v4, get_unaligned_le64(p)); + p += 8; + } while (p <= limit); + + state->v1 = v1; + state->v2 = v2; + state->v3 = v3; + state->v4 = v4; + } + + if (p < b_end) { + memcpy(state->mem64, p, (size_t)(b_end-p)); + state->memsize = (uint32_t)(b_end - p); + } + + return 0; +} +EXPORT_SYMBOL(xxh64_update); + +uint64_t xxh64_digest(const struct xxh64_state *state) +{ + const uint8_t *p = (const uint8_t *)state->mem64; + const uint8_t *const b_end = (const uint8_t *)state->mem64 + + state->memsize; + uint64_t h64; + + if (state->total_len >= 32) { + const uint64_t v1 = state->v1; + const uint64_t v2 = state->v2; + const uint64_t v3 = state->v3; + const uint64_t v4 = state->v4; + + h64 = xxh_rotl64(v1, 1) + xxh_rotl64(v2, 7) + + xxh_rotl64(v3, 12) + xxh_rotl64(v4, 18); + h64 = xxh64_merge_round(h64, v1); + h64 = xxh64_merge_round(h64, v2); + h64 = xxh64_merge_round(h64, v3); + h64 = xxh64_merge_round(h64, v4); + } else { + h64 = state->v3 + PRIME64_5; + } + + h64 += (uint64_t)state->total_len; + + while (p + 8 <= b_end) { + const uint64_t k1 = xxh64_round(0, get_unaligned_le64(p)); + + h64 ^= k1; + h64 = xxh_rotl64(h64, 27) * PRIME64_1 + PRIME64_4; + p += 8; + } + + if (p + 4 <= b_end) { + h64 ^= (uint64_t)(get_unaligned_le32(p)) * PRIME64_1; + h64 = xxh_rotl64(h64, 23) * PRIME64_2 + PRIME64_3; + p += 4; + } + + while (p < b_end) { + h64 ^= (*p) * PRIME64_5; + h64 = xxh_rotl64(h64, 11) * PRIME64_1; + p++; + } + + h64 ^= h64 >> 33; + h64 *= PRIME64_2; + h64 ^= h64 >> 29; + h64 *= PRIME64_3; + h64 ^= h64 >> 32; + + return h64; +} +EXPORT_SYMBOL(xxh64_digest); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("xxHash"); diff --git a/xen/common/zstd/bitstream.h b/xen/common/zstd/bitstream.h new file mode 100644 index 0000000000..3a49784d5c --- /dev/null +++ b/xen/common/zstd/bitstream.h @@ -0,0 +1,379 @@ +/* + * bitstream + * Part of FSE library + * header file (to include) + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ +#ifndef BITSTREAM_H_MODULE +#define BITSTREAM_H_MODULE + +/* +* This API consists of small unitary functions, which must be inlined for best performance. +* Since link-time-optimization is not available for all compilers, +* these functions are defined into a .h to be included. +*/ + +/*-**************************************** +* Dependencies +******************************************/ +#include "error_private.h" /* error codes and messages */ +#include "mem.h" /* unaligned access routines */ + +/*========================================= +* Target specific +=========================================*/ +#define STREAM_ACCUMULATOR_MIN_32 25 +#define STREAM_ACCUMULATOR_MIN_64 57 +#define STREAM_ACCUMULATOR_MIN ((U32)(ZSTD_32bits() ? STREAM_ACCUMULATOR_MIN_32 : STREAM_ACCUMULATOR_MIN_64)) + +/*-****************************************** +* bitStream encoding API (write forward) +********************************************/ +/* bitStream can mix input from multiple sources. +* A critical property of these streams is that they encode and decode in **reverse** direction. +* So the first bit sequence you add will be the last to be read, like a LIFO stack. +*/ +typedef struct { + size_t bitContainer; + int bitPos; + char *startPtr; + char *ptr; + char *endPtr; +} BIT_CStream_t; + +ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *dstBuffer, size_t dstCapacity); +ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits); +ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC); +ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC); + +/* Start with initCStream, providing the size of buffer to write into. +* bitStream will never write outside of this buffer. +* `dstCapacity` must be >= sizeof(bitD->bitContainer), otherwise @return will be an error code. +* +* bits are first added to a local register. +* Local register is size_t, hence 64-bits on 64-bits systems, or 32-bits on 32-bits systems. +* Writing data into memory is an explicit operation, performed by the flushBits function. +* Hence keep track how many bits are potentially stored into local register to avoid register overflow. +* After a flushBits, a maximum of 7 bits might still be stored into local register. +* +* Avoid storing elements of more than 24 bits if you want compatibility with 32-bits bitstream readers. +* +* Last operation is to close the bitStream. +* The function returns the final size of CStream in bytes. +* If data couldn't fit into `dstBuffer`, it will return a 0 ( == not storable) +*/ + +/*-******************************************** +* bitStream decoding API (read backward) +**********************************************/ +typedef struct { + size_t bitContainer; + unsigned bitsConsumed; + const char *ptr; + const char *start; +} BIT_DStream_t; + +typedef enum { + BIT_DStream_unfinished = 0, + BIT_DStream_endOfBuffer = 1, + BIT_DStream_completed = 2, + BIT_DStream_overflow = 3 +} BIT_DStream_status; /* result of BIT_reloadDStream() */ +/* 1,2,4,8 would be better for bitmap combinations, but slows down performance a bit ... :( */ + +ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize); +ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, unsigned nbBits); +ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD); +ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *bitD); + +/* Start by invoking BIT_initDStream(). +* A chunk of the bitStream is then stored into a local register. +* Local register size is 64-bits on 64-bits systems, 32-bits on 32-bits systems (size_t). +* You can then retrieve bitFields stored into the local register, **in reverse order**. +* Local register is explicitly reloaded from memory by the BIT_reloadDStream() method. +* A reload guarantee a minimum of ((8*sizeof(bitD->bitContainer))-7) bits when its result is BIT_DStream_unfinished. +* Otherwise, it can be less than that, so proceed accordingly. +* Checking if DStream has reached its end can be performed with BIT_endOfDStream(). +*/ + +/*-**************************************** +* unsafe API +******************************************/ +ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits); +/* faster, but works only if value is "clean", meaning all high bits above nbBits are 0 */ + +ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC); +/* unsafe version; does not check buffer overflow */ + +ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, unsigned nbBits); +/* faster, but works only if nbBits >= 1 */ + +/*-************************************************************** +* Internal functions +****************************************************************/ +ZSTD_STATIC unsigned BIT_highbit32(register U32 val) { return 31 - __builtin_clz(val); } + +/*===== Local Constants =====*/ +static const unsigned BIT_mask[] = {0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, 0xFF, + 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, + 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF}; /* up to 26 bits */ + +/*-************************************************************** +* bitStream encoding +****************************************************************/ +/*! BIT_initCStream() : + * `dstCapacity` must be > sizeof(void*) + * @return : 0 if success, + otherwise an error code (can be tested using ERR_isError() ) */ +ZSTD_STATIC size_t BIT_initCStream(BIT_CStream_t *bitC, void *startPtr, size_t dstCapacity) +{ + bitC->bitContainer = 0; + bitC->bitPos = 0; + bitC->startPtr = (char *)startPtr; + bitC->ptr = bitC->startPtr; + bitC->endPtr = bitC->startPtr + dstCapacity - sizeof(bitC->ptr); + if (dstCapacity <= sizeof(bitC->ptr)) + return ERROR(dstSize_tooSmall); + return 0; +} + +/*! BIT_addBits() : + can add up to 26 bits into `bitC`. + Does not check for register overflow ! */ +ZSTD_STATIC void BIT_addBits(BIT_CStream_t *bitC, size_t value, unsigned nbBits) +{ + bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos; + bitC->bitPos += nbBits; +} + +/*! BIT_addBitsFast() : + * works only if `value` is _clean_, meaning all high bits above nbBits are 0 */ +ZSTD_STATIC void BIT_addBitsFast(BIT_CStream_t *bitC, size_t value, unsigned nbBits) +{ + bitC->bitContainer |= value << bitC->bitPos; + bitC->bitPos += nbBits; +} + +/*! BIT_flushBitsFast() : + * unsafe version; does not check buffer overflow */ +ZSTD_STATIC void BIT_flushBitsFast(BIT_CStream_t *bitC) +{ + size_t const nbBytes = bitC->bitPos >> 3; + ZSTD_writeLEST(bitC->ptr, bitC->bitContainer); + bitC->ptr += nbBytes; + bitC->bitPos &= 7; + bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */ +} + +/*! BIT_flushBits() : + * safe version; check for buffer overflow, and prevents it. + * note : does not signal buffer overflow. This will be revealed later on using BIT_closeCStream() */ +ZSTD_STATIC void BIT_flushBits(BIT_CStream_t *bitC) +{ + size_t const nbBytes = bitC->bitPos >> 3; + ZSTD_writeLEST(bitC->ptr, bitC->bitContainer); + bitC->ptr += nbBytes; + if (bitC->ptr > bitC->endPtr) + bitC->ptr = bitC->endPtr; + bitC->bitPos &= 7; + bitC->bitContainer >>= nbBytes * 8; /* if bitPos >= sizeof(bitContainer)*8 --> undefined behavior */ +} + +/*! BIT_closeCStream() : + * @return : size of CStream, in bytes, + or 0 if it could not fit into dstBuffer */ +ZSTD_STATIC size_t BIT_closeCStream(BIT_CStream_t *bitC) +{ + BIT_addBitsFast(bitC, 1, 1); /* endMark */ + BIT_flushBits(bitC); + + if (bitC->ptr >= bitC->endPtr) + return 0; /* doesn't fit within authorized budget : cancel */ + + return (bitC->ptr - bitC->startPtr) + (bitC->bitPos > 0); +} + +/*-******************************************************** +* bitStream decoding +**********************************************************/ +/*! BIT_initDStream() : +* Initialize a BIT_DStream_t. +* `bitD` : a pointer to an already allocated BIT_DStream_t structure. +* `srcSize` must be the *exact* size of the bitStream, in bytes. +* @return : size of stream (== srcSize) or an errorCode if a problem is detected +*/ +ZSTD_STATIC size_t BIT_initDStream(BIT_DStream_t *bitD, const void *srcBuffer, size_t srcSize) +{ + if (srcSize < 1) { + memset(bitD, 0, sizeof(*bitD)); + return ERROR(srcSize_wrong); + } + + if (srcSize >= sizeof(bitD->bitContainer)) { /* normal case */ + bitD->start = (const char *)srcBuffer; + bitD->ptr = (const char *)srcBuffer + srcSize - sizeof(bitD->bitContainer); + bitD->bitContainer = ZSTD_readLEST(bitD->ptr); + { + BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1]; + bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; /* ensures bitsConsumed is always set */ + if (lastByte == 0) + return ERROR(GENERIC); /* endMark not present */ + } + } else { + bitD->start = (const char *)srcBuffer; + bitD->ptr = bitD->start; + bitD->bitContainer = *(const BYTE *)(bitD->start); + switch (srcSize) { + case 7: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[6]) << (sizeof(bitD->bitContainer) * 8 - 16); + /* fall through */ + case 6: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[5]) << (sizeof(bitD->bitContainer) * 8 - 24); + /* fall through */ + case 5: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[4]) << (sizeof(bitD->bitContainer) * 8 - 32); + /* fall through */ + case 4: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[3]) << 24; + /* fall through */ + case 3: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[2]) << 16; + /* fall through */ + case 2: bitD->bitContainer += (size_t)(((const BYTE *)(srcBuffer))[1]) << 8; + default:; + } + { + BYTE const lastByte = ((const BYTE *)srcBuffer)[srcSize - 1]; + bitD->bitsConsumed = lastByte ? 8 - BIT_highbit32(lastByte) : 0; + if (lastByte == 0) + return ERROR(GENERIC); /* endMark not present */ + } + bitD->bitsConsumed += (U32)(sizeof(bitD->bitContainer) - srcSize) * 8; + } + + return srcSize; +} + +ZSTD_STATIC size_t BIT_getUpperBits(size_t bitContainer, U32 const start) { return bitContainer >> start; } + +ZSTD_STATIC size_t BIT_getMiddleBits(size_t bitContainer, U32 const start, U32 const nbBits) { return (bitContainer >> start) & BIT_mask[nbBits]; } + +ZSTD_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits) { return bitContainer & BIT_mask[nbBits]; } + +/*! BIT_lookBits() : + * Provides next n bits from local register. + * local register is not modified. + * On 32-bits, maxNbBits==24. + * On 64-bits, maxNbBits==56. + * @return : value extracted + */ +ZSTD_STATIC size_t BIT_lookBits(const BIT_DStream_t *bitD, U32 nbBits) +{ + U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1; + return ((bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> 1) >> ((bitMask - nbBits) & bitMask); +} + +/*! BIT_lookBitsFast() : +* unsafe version; only works only if nbBits >= 1 */ +ZSTD_STATIC size_t BIT_lookBitsFast(const BIT_DStream_t *bitD, U32 nbBits) +{ + U32 const bitMask = sizeof(bitD->bitContainer) * 8 - 1; + return (bitD->bitContainer << (bitD->bitsConsumed & bitMask)) >> (((bitMask + 1) - nbBits) & bitMask); +} + +ZSTD_STATIC void BIT_skipBits(BIT_DStream_t *bitD, U32 nbBits) { bitD->bitsConsumed += nbBits; } + +/*! BIT_readBits() : + * Read (consume) next n bits from local register and update. + * Pay attention to not read more than nbBits contained into local register. + * @return : extracted value. + */ +ZSTD_STATIC size_t BIT_readBits(BIT_DStream_t *bitD, U32 nbBits) +{ + size_t const value = BIT_lookBits(bitD, nbBits); + BIT_skipBits(bitD, nbBits); + return value; +} + +/*! BIT_readBitsFast() : +* unsafe version; only works only if nbBits >= 1 */ +ZSTD_STATIC size_t BIT_readBitsFast(BIT_DStream_t *bitD, U32 nbBits) +{ + size_t const value = BIT_lookBitsFast(bitD, nbBits); + BIT_skipBits(bitD, nbBits); + return value; +} + +/*! BIT_reloadDStream() : +* Refill `bitD` from buffer previously set in BIT_initDStream() . +* This function is safe, it guarantees it will not read beyond src buffer. +* @return : status of `BIT_DStream_t` internal register. + if status == BIT_DStream_unfinished, internal register is filled with >= (sizeof(bitD->bitContainer)*8 - 7) bits */ +ZSTD_STATIC BIT_DStream_status BIT_reloadDStream(BIT_DStream_t *bitD) +{ + if (bitD->bitsConsumed > (sizeof(bitD->bitContainer) * 8)) /* should not happen => corruption detected */ + return BIT_DStream_overflow; + + if (bitD->ptr >= bitD->start + sizeof(bitD->bitContainer)) { + bitD->ptr -= bitD->bitsConsumed >> 3; + bitD->bitsConsumed &= 7; + bitD->bitContainer = ZSTD_readLEST(bitD->ptr); + return BIT_DStream_unfinished; + } + if (bitD->ptr == bitD->start) { + if (bitD->bitsConsumed < sizeof(bitD->bitContainer) * 8) + return BIT_DStream_endOfBuffer; + return BIT_DStream_completed; + } + { + U32 nbBytes = bitD->bitsConsumed >> 3; + BIT_DStream_status result = BIT_DStream_unfinished; + if (bitD->ptr - nbBytes < bitD->start) { + nbBytes = (U32)(bitD->ptr - bitD->start); /* ptr > start */ + result = BIT_DStream_endOfBuffer; + } + bitD->ptr -= nbBytes; + bitD->bitsConsumed -= nbBytes * 8; + bitD->bitContainer = ZSTD_readLEST(bitD->ptr); /* reminder : srcSize > sizeof(bitD) */ + return result; + } +} + +/*! BIT_endOfDStream() : +* @return Tells if DStream has exactly reached its end (all bits consumed). +*/ +ZSTD_STATIC unsigned BIT_endOfDStream(const BIT_DStream_t *DStream) +{ + return ((DStream->ptr == DStream->start) && (DStream->bitsConsumed == sizeof(DStream->bitContainer) * 8)); +} + +#endif /* BITSTREAM_H_MODULE */ diff --git a/xen/common/zstd/decompress.c b/xen/common/zstd/decompress.c new file mode 100644 index 0000000000..db6761ea4d --- /dev/null +++ b/xen/common/zstd/decompress.c @@ -0,0 +1,2531 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/* *************************************************************** +* Tuning parameters +*****************************************************************/ +/*! +* MAXWINDOWSIZE_DEFAULT : +* maximum window size accepted by DStream, by default. +* Frames requiring more memory will be rejected. +*/ +#ifndef ZSTD_MAXWINDOWSIZE_DEFAULT +#define ZSTD_MAXWINDOWSIZE_DEFAULT ((1 << ZSTD_WINDOWLOG_MAX) + 1) /* defined within zstd.h */ +#endif + +/*-******************************************************* +* Dependencies +*********************************************************/ +#include "fse.h" +#include "huf.h" +#include "mem.h" /* low level memory routines */ +#include "zstd_internal.h" +#include +#include +#include /* memcpy, memmove, memset */ + +#define ZSTD_PREFETCH(ptr) __builtin_prefetch(ptr, 0, 0) + +/*-************************************* +* Macros +***************************************/ +#define ZSTD_isError ERR_isError /* for inlining */ +#define FSE_isError ERR_isError +#define HUF_isError ERR_isError + +/*_******************************************************* +* Memory operations +**********************************************************/ +static void ZSTD_copy4(void *dst, const void *src) { memcpy(dst, src, 4); } + +/*-************************************************************* +* Context management +***************************************************************/ +typedef enum { + ZSTDds_getFrameHeaderSize, + ZSTDds_decodeFrameHeader, + ZSTDds_decodeBlockHeader, + ZSTDds_decompressBlock, + ZSTDds_decompressLastBlock, + ZSTDds_checkChecksum, + ZSTDds_decodeSkippableHeader, + ZSTDds_skipFrame +} ZSTD_dStage; + +typedef struct { + FSE_DTable LLTable[FSE_DTABLE_SIZE_U32(LLFSELog)]; + FSE_DTable OFTable[FSE_DTABLE_SIZE_U32(OffFSELog)]; + FSE_DTable MLTable[FSE_DTABLE_SIZE_U32(MLFSELog)]; + HUF_DTable hufTable[HUF_DTABLE_SIZE(HufLog)]; /* can accommodate HUF_decompress4X */ + U64 workspace[HUF_DECOMPRESS_WORKSPACE_SIZE_U32 / 2]; + U32 rep[ZSTD_REP_NUM]; +} ZSTD_entropyTables_t; + +struct ZSTD_DCtx_s { + const FSE_DTable *LLTptr; + const FSE_DTable *MLTptr; + const FSE_DTable *OFTptr; + const HUF_DTable *HUFptr; + ZSTD_entropyTables_t entropy; + const void *previousDstEnd; /* detect continuity */ + const void *base; /* start of curr segment */ + const void *vBase; /* virtual start of previous segment if it was just before curr one */ + const void *dictEnd; /* end of previous segment */ + size_t expected; + ZSTD_frameParams fParams; + blockType_e bType; /* used in ZSTD_decompressContinue(), to transfer blockType between header decoding and block decoding stages */ + ZSTD_dStage stage; + U32 litEntropy; + U32 fseEntropy; + struct xxh64_state xxhState; + size_t headerSize; + U32 dictID; + const BYTE *litPtr; + ZSTD_customMem customMem; + size_t litSize; + size_t rleSize; + BYTE litBuffer[ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH]; + BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; +}; /* typedef'd to ZSTD_DCtx within "zstd.h" */ + +size_t ZSTD_DCtxWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DCtx)); } + +size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx) +{ + dctx->expected = ZSTD_frameHeaderSize_prefix; + dctx->stage = ZSTDds_getFrameHeaderSize; + dctx->previousDstEnd = NULL; + dctx->base = NULL; + dctx->vBase = NULL; + dctx->dictEnd = NULL; + dctx->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ + dctx->litEntropy = dctx->fseEntropy = 0; + dctx->dictID = 0; + ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.rep) == sizeof(repStartValue)); + memcpy(dctx->entropy.rep, repStartValue, sizeof(repStartValue)); /* initial repcodes */ + dctx->LLTptr = dctx->entropy.LLTable; + dctx->MLTptr = dctx->entropy.MLTable; + dctx->OFTptr = dctx->entropy.OFTable; + dctx->HUFptr = dctx->entropy.hufTable; + return 0; +} + +ZSTD_DCtx *ZSTD_createDCtx_advanced(ZSTD_customMem customMem) +{ + ZSTD_DCtx *dctx; + + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + dctx = (ZSTD_DCtx *)ZSTD_malloc(sizeof(ZSTD_DCtx), customMem); + if (!dctx) + return NULL; + memcpy(&dctx->customMem, &customMem, sizeof(customMem)); + ZSTD_decompressBegin(dctx); + return dctx; +} + +ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + return ZSTD_createDCtx_advanced(stackMem); +} + +size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx) +{ + if (dctx == NULL) + return 0; /* support free on NULL */ + ZSTD_free(dctx, dctx->customMem); + return 0; /* reserved as a potential error code in the future */ +} + +void ZSTD_copyDCtx(ZSTD_DCtx *dstDCtx, const ZSTD_DCtx *srcDCtx) +{ + size_t const workSpaceSize = (ZSTD_BLOCKSIZE_ABSOLUTEMAX + WILDCOPY_OVERLENGTH) + ZSTD_frameHeaderSize_max; + memcpy(dstDCtx, srcDCtx, sizeof(ZSTD_DCtx) - workSpaceSize); /* no need to copy workspace */ +} + +static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict); + +/*-************************************************************* +* Decompression section +***************************************************************/ + +/*! ZSTD_isFrame() : + * Tells if the content of `buffer` starts with a valid Frame Identifier. + * Note : Frame Identifier is 4 bytes. If `size < 4`, @return will always be 0. + * Note 2 : Legacy Frame Identifiers are considered valid only if Legacy Support is enabled. + * Note 3 : Skippable Frame Identifiers are considered valid. */ +unsigned ZSTD_isFrame(const void *buffer, size_t size) +{ + if (size < 4) + return 0; + { + U32 const magic = ZSTD_readLE32(buffer); + if (magic == ZSTD_MAGICNUMBER) + return 1; + if ((magic & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) + return 1; + } + return 0; +} + +/** ZSTD_frameHeaderSize() : +* srcSize must be >= ZSTD_frameHeaderSize_prefix. +* @return : size of the Frame Header */ +static size_t ZSTD_frameHeaderSize(const void *src, size_t srcSize) +{ + if (srcSize < ZSTD_frameHeaderSize_prefix) + return ERROR(srcSize_wrong); + { + BYTE const fhd = ((const BYTE *)src)[4]; + U32 const dictID = fhd & 3; + U32 const singleSegment = (fhd >> 5) & 1; + U32 const fcsId = fhd >> 6; + return ZSTD_frameHeaderSize_prefix + !singleSegment + ZSTD_did_fieldSize[dictID] + ZSTD_fcs_fieldSize[fcsId] + (singleSegment && !fcsId); + } +} + +/** ZSTD_getFrameParams() : +* decode Frame Header, or require larger `srcSize`. +* @return : 0, `fparamsPtr` is correctly filled, +* >0, `srcSize` is too small, result is expected `srcSize`, +* or an error code, which can be tested using ZSTD_isError() */ +size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src, size_t srcSize) +{ + const BYTE *ip = (const BYTE *)src; + + if (srcSize < ZSTD_frameHeaderSize_prefix) + return ZSTD_frameHeaderSize_prefix; + if (ZSTD_readLE32(src) != ZSTD_MAGICNUMBER) { + if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + if (srcSize < ZSTD_skippableHeaderSize) + return ZSTD_skippableHeaderSize; /* magic number + skippable frame length */ + memset(fparamsPtr, 0, sizeof(*fparamsPtr)); + fparamsPtr->frameContentSize = ZSTD_readLE32((const char *)src + 4); + fparamsPtr->windowSize = 0; /* windowSize==0 means a frame is skippable */ + return 0; + } + return ERROR(prefix_unknown); + } + + /* ensure there is enough `srcSize` to fully read/decode frame header */ + { + size_t const fhsize = ZSTD_frameHeaderSize(src, srcSize); + if (srcSize < fhsize) + return fhsize; + } + + { + BYTE const fhdByte = ip[4]; + size_t pos = 5; + U32 const dictIDSizeCode = fhdByte & 3; + U32 const checksumFlag = (fhdByte >> 2) & 1; + U32 const singleSegment = (fhdByte >> 5) & 1; + U32 const fcsID = fhdByte >> 6; + U32 const windowSizeMax = 1U << ZSTD_WINDOWLOG_MAX; + U32 windowSize = 0; + U32 dictID = 0; + U64 frameContentSize = 0; + if ((fhdByte & 0x08) != 0) + return ERROR(frameParameter_unsupported); /* reserved bits, which must be zero */ + if (!singleSegment) { + BYTE const wlByte = ip[pos++]; + U32 const windowLog = (wlByte >> 3) + ZSTD_WINDOWLOG_ABSOLUTEMIN; + if (windowLog > ZSTD_WINDOWLOG_MAX) + return ERROR(frameParameter_windowTooLarge); /* avoids issue with 1 << windowLog */ + windowSize = (1U << windowLog); + windowSize += (windowSize >> 3) * (wlByte & 7); + } + + switch (dictIDSizeCode) { + default: /* impossible */ + case 0: break; + case 1: + dictID = ip[pos]; + pos++; + break; + case 2: + dictID = ZSTD_readLE16(ip + pos); + pos += 2; + break; + case 3: + dictID = ZSTD_readLE32(ip + pos); + pos += 4; + break; + } + switch (fcsID) { + default: /* impossible */ + case 0: + if (singleSegment) + frameContentSize = ip[pos]; + break; + case 1: frameContentSize = ZSTD_readLE16(ip + pos) + 256; break; + case 2: frameContentSize = ZSTD_readLE32(ip + pos); break; + case 3: frameContentSize = ZSTD_readLE64(ip + pos); break; + } + if (!windowSize) + windowSize = (U32)frameContentSize; + if (windowSize > windowSizeMax) + return ERROR(frameParameter_windowTooLarge); + fparamsPtr->frameContentSize = frameContentSize; + fparamsPtr->windowSize = windowSize; + fparamsPtr->dictID = dictID; + fparamsPtr->checksumFlag = checksumFlag; + } + return 0; +} + +/** ZSTD_getFrameContentSize() : +* compatible with legacy mode +* @return : decompressed size of the single frame pointed to be `src` if known, otherwise +* - ZSTD_CONTENTSIZE_UNKNOWN if the size cannot be determined +* - ZSTD_CONTENTSIZE_ERROR if an error occurred (e.g. invalid magic number, srcSize too small) */ +unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize) +{ + { + ZSTD_frameParams fParams; + if (ZSTD_getFrameParams(&fParams, src, srcSize) != 0) + return ZSTD_CONTENTSIZE_ERROR; + if (fParams.windowSize == 0) { + /* Either skippable or empty frame, size == 0 either way */ + return 0; + } else if (fParams.frameContentSize != 0) { + return fParams.frameContentSize; + } else { + return ZSTD_CONTENTSIZE_UNKNOWN; + } + } +} + +/** ZSTD_findDecompressedSize() : + * compatible with legacy mode + * `srcSize` must be the exact length of some number of ZSTD compressed and/or + * skippable frames + * @return : decompressed size of the frames contained */ +unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize) +{ + { + unsigned long long totalDstSize = 0; + while (srcSize >= ZSTD_frameHeaderSize_prefix) { + const U32 magicNumber = ZSTD_readLE32(src); + + if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + size_t skippableSize; + if (srcSize < ZSTD_skippableHeaderSize) + return ERROR(srcSize_wrong); + skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize; + if (srcSize < skippableSize) { + return ZSTD_CONTENTSIZE_ERROR; + } + + src = (const BYTE *)src + skippableSize; + srcSize -= skippableSize; + continue; + } + + { + unsigned long long const ret = ZSTD_getFrameContentSize(src, srcSize); + if (ret >= ZSTD_CONTENTSIZE_ERROR) + return ret; + + /* check for overflow */ + if (totalDstSize + ret < totalDstSize) + return ZSTD_CONTENTSIZE_ERROR; + totalDstSize += ret; + } + { + size_t const frameSrcSize = ZSTD_findFrameCompressedSize(src, srcSize); + if (ZSTD_isError(frameSrcSize)) { + return ZSTD_CONTENTSIZE_ERROR; + } + + src = (const BYTE *)src + frameSrcSize; + srcSize -= frameSrcSize; + } + } + + if (srcSize) { + return ZSTD_CONTENTSIZE_ERROR; + } + + return totalDstSize; + } +} + +/** ZSTD_decodeFrameHeader() : +* `headerSize` must be the size provided by ZSTD_frameHeaderSize(). +* @return : 0 if success, or an error code, which can be tested using ZSTD_isError() */ +static size_t ZSTD_decodeFrameHeader(ZSTD_DCtx *dctx, const void *src, size_t headerSize) +{ + size_t const result = ZSTD_getFrameParams(&(dctx->fParams), src, headerSize); + if (ZSTD_isError(result)) + return result; /* invalid header */ + if (result > 0) + return ERROR(srcSize_wrong); /* headerSize too small */ + if (dctx->fParams.dictID && (dctx->dictID != dctx->fParams.dictID)) + return ERROR(dictionary_wrong); + if (dctx->fParams.checksumFlag) + xxh64_reset(&dctx->xxhState, 0); + return 0; +} + +typedef struct { + blockType_e blockType; + U32 lastBlock; + U32 origSize; +} blockProperties_t; + +/*! ZSTD_getcBlockSize() : +* Provides the size of compressed block from block header `src` */ +size_t ZSTD_getcBlockSize(const void *src, size_t srcSize, blockProperties_t *bpPtr) +{ + if (srcSize < ZSTD_blockHeaderSize) + return ERROR(srcSize_wrong); + { + U32 const cBlockHeader = ZSTD_readLE24(src); + U32 const cSize = cBlockHeader >> 3; + bpPtr->lastBlock = cBlockHeader & 1; + bpPtr->blockType = (blockType_e)((cBlockHeader >> 1) & 3); + bpPtr->origSize = cSize; /* only useful for RLE */ + if (bpPtr->blockType == bt_rle) + return 1; + if (bpPtr->blockType == bt_reserved) + return ERROR(corruption_detected); + return cSize; + } +} + +static size_t ZSTD_copyRawBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + if (srcSize > dstCapacity) + return ERROR(dstSize_tooSmall); + memcpy(dst, src, srcSize); + return srcSize; +} + +static size_t ZSTD_setRleBlock(void *dst, size_t dstCapacity, const void *src, size_t srcSize, size_t regenSize) +{ + if (srcSize != 1) + return ERROR(srcSize_wrong); + if (regenSize > dstCapacity) + return ERROR(dstSize_tooSmall); + memset(dst, *(const BYTE *)src, regenSize); + return regenSize; +} + +/*! ZSTD_decodeLiteralsBlock() : + @return : nb of bytes read from src (< srcSize ) */ +size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx *dctx, const void *src, size_t srcSize) /* note : srcSize < BLOCKSIZE */ +{ + if (srcSize < MIN_CBLOCK_SIZE) + return ERROR(corruption_detected); + + { + const BYTE *const istart = (const BYTE *)src; + symbolEncodingType_e const litEncType = (symbolEncodingType_e)(istart[0] & 3); + + switch (litEncType) { + case set_repeat: + if (dctx->litEntropy == 0) + return ERROR(dictionary_corrupted); + /* fall through */ + case set_compressed: + if (srcSize < 5) + return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for case 3 */ + { + size_t lhSize, litSize, litCSize; + U32 singleStream = 0; + U32 const lhlCode = (istart[0] >> 2) & 3; + U32 const lhc = ZSTD_readLE32(istart); + switch (lhlCode) { + case 0: + case 1: + default: /* note : default is impossible, since lhlCode into [0..3] */ + /* 2 - 2 - 10 - 10 */ + singleStream = !lhlCode; + lhSize = 3; + litSize = (lhc >> 4) & 0x3FF; + litCSize = (lhc >> 14) & 0x3FF; + break; + case 2: + /* 2 - 2 - 14 - 14 */ + lhSize = 4; + litSize = (lhc >> 4) & 0x3FFF; + litCSize = lhc >> 18; + break; + case 3: + /* 2 - 2 - 18 - 18 */ + lhSize = 5; + litSize = (lhc >> 4) & 0x3FFFF; + litCSize = (lhc >> 22) + (istart[4] << 10); + break; + } + if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) + return ERROR(corruption_detected); + if (litCSize + lhSize > srcSize) + return ERROR(corruption_detected); + + if (HUF_isError( + (litEncType == set_repeat) + ? (singleStream ? HUF_decompress1X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr) + : HUF_decompress4X_usingDTable(dctx->litBuffer, litSize, istart + lhSize, litCSize, dctx->HUFptr)) + : (singleStream + ? HUF_decompress1X2_DCtx_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize, + dctx->entropy.workspace, sizeof(dctx->entropy.workspace)) + : HUF_decompress4X_hufOnly_wksp(dctx->entropy.hufTable, dctx->litBuffer, litSize, istart + lhSize, litCSize, + dctx->entropy.workspace, sizeof(dctx->entropy.workspace))))) + return ERROR(corruption_detected); + + dctx->litPtr = dctx->litBuffer; + dctx->litSize = litSize; + dctx->litEntropy = 1; + if (litEncType == set_compressed) + dctx->HUFptr = dctx->entropy.hufTable; + memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); + return litCSize + lhSize; + } + + case set_basic: { + size_t litSize, lhSize; + U32 const lhlCode = ((istart[0]) >> 2) & 3; + switch (lhlCode) { + case 0: + case 2: + default: /* note : default is impossible, since lhlCode into [0..3] */ + lhSize = 1; + litSize = istart[0] >> 3; + break; + case 1: + lhSize = 2; + litSize = ZSTD_readLE16(istart) >> 4; + break; + case 3: + lhSize = 3; + litSize = ZSTD_readLE24(istart) >> 4; + break; + } + + if (lhSize + litSize + WILDCOPY_OVERLENGTH > srcSize) { /* risk reading beyond src buffer with wildcopy */ + if (litSize + lhSize > srcSize) + return ERROR(corruption_detected); + memcpy(dctx->litBuffer, istart + lhSize, litSize); + dctx->litPtr = dctx->litBuffer; + dctx->litSize = litSize; + memset(dctx->litBuffer + dctx->litSize, 0, WILDCOPY_OVERLENGTH); + return lhSize + litSize; + } + /* direct reference into compressed stream */ + dctx->litPtr = istart + lhSize; + dctx->litSize = litSize; + return lhSize + litSize; + } + + case set_rle: { + U32 const lhlCode = ((istart[0]) >> 2) & 3; + size_t litSize, lhSize; + switch (lhlCode) { + case 0: + case 2: + default: /* note : default is impossible, since lhlCode into [0..3] */ + lhSize = 1; + litSize = istart[0] >> 3; + break; + case 1: + lhSize = 2; + litSize = ZSTD_readLE16(istart) >> 4; + break; + case 3: + lhSize = 3; + litSize = ZSTD_readLE24(istart) >> 4; + if (srcSize < 4) + return ERROR(corruption_detected); /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need lhSize+1 = 4 */ + break; + } + if (litSize > ZSTD_BLOCKSIZE_ABSOLUTEMAX) + return ERROR(corruption_detected); + memset(dctx->litBuffer, istart[lhSize], litSize + WILDCOPY_OVERLENGTH); + dctx->litPtr = dctx->litBuffer; + dctx->litSize = litSize; + return lhSize + 1; + } + default: + return ERROR(corruption_detected); /* impossible */ + } + } +} + +typedef union { + FSE_decode_t realData; + U32 alignedBy4; +} FSE_decode_t4; + +static const FSE_decode_t4 LL_defaultDTable[(1 << LL_DEFAULTNORMLOG) + 1] = { + {{LL_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ + {{0, 0, 4}}, /* 0 : base, symbol, bits */ + {{16, 0, 4}}, + {{32, 1, 5}}, + {{0, 3, 5}}, + {{0, 4, 5}}, + {{0, 6, 5}}, + {{0, 7, 5}}, + {{0, 9, 5}}, + {{0, 10, 5}}, + {{0, 12, 5}}, + {{0, 14, 6}}, + {{0, 16, 5}}, + {{0, 18, 5}}, + {{0, 19, 5}}, + {{0, 21, 5}}, + {{0, 22, 5}}, + {{0, 24, 5}}, + {{32, 25, 5}}, + {{0, 26, 5}}, + {{0, 27, 6}}, + {{0, 29, 6}}, + {{0, 31, 6}}, + {{32, 0, 4}}, + {{0, 1, 4}}, + {{0, 2, 5}}, + {{32, 4, 5}}, + {{0, 5, 5}}, + {{32, 7, 5}}, + {{0, 8, 5}}, + {{32, 10, 5}}, + {{0, 11, 5}}, + {{0, 13, 6}}, + {{32, 16, 5}}, + {{0, 17, 5}}, + {{32, 19, 5}}, + {{0, 20, 5}}, + {{32, 22, 5}}, + {{0, 23, 5}}, + {{0, 25, 4}}, + {{16, 25, 4}}, + {{32, 26, 5}}, + {{0, 28, 6}}, + {{0, 30, 6}}, + {{48, 0, 4}}, + {{16, 1, 4}}, + {{32, 2, 5}}, + {{32, 3, 5}}, + {{32, 5, 5}}, + {{32, 6, 5}}, + {{32, 8, 5}}, + {{32, 9, 5}}, + {{32, 11, 5}}, + {{32, 12, 5}}, + {{0, 15, 6}}, + {{32, 17, 5}}, + {{32, 18, 5}}, + {{32, 20, 5}}, + {{32, 21, 5}}, + {{32, 23, 5}}, + {{32, 24, 5}}, + {{0, 35, 6}}, + {{0, 34, 6}}, + {{0, 33, 6}}, + {{0, 32, 6}}, +}; /* LL_defaultDTable */ + +static const FSE_decode_t4 ML_defaultDTable[(1 << ML_DEFAULTNORMLOG) + 1] = { + {{ML_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ + {{0, 0, 6}}, /* 0 : base, symbol, bits */ + {{0, 1, 4}}, + {{32, 2, 5}}, + {{0, 3, 5}}, + {{0, 5, 5}}, + {{0, 6, 5}}, + {{0, 8, 5}}, + {{0, 10, 6}}, + {{0, 13, 6}}, + {{0, 16, 6}}, + {{0, 19, 6}}, + {{0, 22, 6}}, + {{0, 25, 6}}, + {{0, 28, 6}}, + {{0, 31, 6}}, + {{0, 33, 6}}, + {{0, 35, 6}}, + {{0, 37, 6}}, + {{0, 39, 6}}, + {{0, 41, 6}}, + {{0, 43, 6}}, + {{0, 45, 6}}, + {{16, 1, 4}}, + {{0, 2, 4}}, + {{32, 3, 5}}, + {{0, 4, 5}}, + {{32, 6, 5}}, + {{0, 7, 5}}, + {{0, 9, 6}}, + {{0, 12, 6}}, + {{0, 15, 6}}, + {{0, 18, 6}}, + {{0, 21, 6}}, + {{0, 24, 6}}, + {{0, 27, 6}}, + {{0, 30, 6}}, + {{0, 32, 6}}, + {{0, 34, 6}}, + {{0, 36, 6}}, + {{0, 38, 6}}, + {{0, 40, 6}}, + {{0, 42, 6}}, + {{0, 44, 6}}, + {{32, 1, 4}}, + {{48, 1, 4}}, + {{16, 2, 4}}, + {{32, 4, 5}}, + {{32, 5, 5}}, + {{32, 7, 5}}, + {{32, 8, 5}}, + {{0, 11, 6}}, + {{0, 14, 6}}, + {{0, 17, 6}}, + {{0, 20, 6}}, + {{0, 23, 6}}, + {{0, 26, 6}}, + {{0, 29, 6}}, + {{0, 52, 6}}, + {{0, 51, 6}}, + {{0, 50, 6}}, + {{0, 49, 6}}, + {{0, 48, 6}}, + {{0, 47, 6}}, + {{0, 46, 6}}, +}; /* ML_defaultDTable */ + +static const FSE_decode_t4 OF_defaultDTable[(1 << OF_DEFAULTNORMLOG) + 1] = { + {{OF_DEFAULTNORMLOG, 1, 1}}, /* header : tableLog, fastMode, fastMode */ + {{0, 0, 5}}, /* 0 : base, symbol, bits */ + {{0, 6, 4}}, + {{0, 9, 5}}, + {{0, 15, 5}}, + {{0, 21, 5}}, + {{0, 3, 5}}, + {{0, 7, 4}}, + {{0, 12, 5}}, + {{0, 18, 5}}, + {{0, 23, 5}}, + {{0, 5, 5}}, + {{0, 8, 4}}, + {{0, 14, 5}}, + {{0, 20, 5}}, + {{0, 2, 5}}, + {{16, 7, 4}}, + {{0, 11, 5}}, + {{0, 17, 5}}, + {{0, 22, 5}}, + {{0, 4, 5}}, + {{16, 8, 4}}, + {{0, 13, 5}}, + {{0, 19, 5}}, + {{0, 1, 5}}, + {{16, 6, 4}}, + {{0, 10, 5}}, + {{0, 16, 5}}, + {{0, 28, 5}}, + {{0, 27, 5}}, + {{0, 26, 5}}, + {{0, 25, 5}}, + {{0, 24, 5}}, +}; /* OF_defaultDTable */ + +/*! ZSTD_buildSeqTable() : + @return : nb bytes read from src, + or an error code if it fails, testable with ZSTD_isError() +*/ +static size_t ZSTD_buildSeqTable(FSE_DTable *DTableSpace, const FSE_DTable **DTablePtr, symbolEncodingType_e type, U32 max, U32 maxLog, const void *src, + size_t srcSize, const FSE_decode_t4 *defaultTable, U32 flagRepeatTable, void *workspace, size_t workspaceSize) +{ + const void *const tmpPtr = defaultTable; /* bypass strict aliasing */ + switch (type) { + case set_rle: + if (!srcSize) + return ERROR(srcSize_wrong); + if ((*(const BYTE *)src) > max) + return ERROR(corruption_detected); + FSE_buildDTable_rle(DTableSpace, *(const BYTE *)src); + *DTablePtr = DTableSpace; + return 1; + case set_basic: *DTablePtr = (const FSE_DTable *)tmpPtr; return 0; + case set_repeat: + if (!flagRepeatTable) + return ERROR(corruption_detected); + return 0; + default: /* impossible */ + case set_compressed: { + U32 tableLog; + S16 *norm = (S16 *)workspace; + size_t const spaceUsed32 = ALIGN(sizeof(S16) * (MaxSeq + 1), sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(GENERIC); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + { + size_t const headerSize = FSE_readNCount(norm, &max, &tableLog, src, srcSize); + if (FSE_isError(headerSize)) + return ERROR(corruption_detected); + if (tableLog > maxLog) + return ERROR(corruption_detected); + FSE_buildDTable_wksp(DTableSpace, norm, max, tableLog, workspace, workspaceSize); + *DTablePtr = DTableSpace; + return headerSize; + } + } + } +} + +size_t ZSTD_decodeSeqHeaders(ZSTD_DCtx *dctx, int *nbSeqPtr, const void *src, size_t srcSize) +{ + const BYTE *const istart = (const BYTE *const)src; + const BYTE *const iend = istart + srcSize; + const BYTE *ip = istart; + + /* check */ + if (srcSize < MIN_SEQUENCES_SIZE) + return ERROR(srcSize_wrong); + + /* SeqHead */ + { + int nbSeq = *ip++; + if (!nbSeq) { + *nbSeqPtr = 0; + return 1; + } + if (nbSeq > 0x7F) { + if (nbSeq == 0xFF) { + if (ip + 2 > iend) + return ERROR(srcSize_wrong); + nbSeq = ZSTD_readLE16(ip) + LONGNBSEQ, ip += 2; + } else { + if (ip >= iend) + return ERROR(srcSize_wrong); + nbSeq = ((nbSeq - 0x80) << 8) + *ip++; + } + } + *nbSeqPtr = nbSeq; + } + + /* FSE table descriptors */ + if (ip + 4 > iend) + return ERROR(srcSize_wrong); /* minimum possible size */ + { + symbolEncodingType_e const LLtype = (symbolEncodingType_e)(*ip >> 6); + symbolEncodingType_e const OFtype = (symbolEncodingType_e)((*ip >> 4) & 3); + symbolEncodingType_e const MLtype = (symbolEncodingType_e)((*ip >> 2) & 3); + ip++; + + /* Build DTables */ + { + size_t const llhSize = ZSTD_buildSeqTable(dctx->entropy.LLTable, &dctx->LLTptr, LLtype, MaxLL, LLFSELog, ip, iend - ip, + LL_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); + if (ZSTD_isError(llhSize)) + return ERROR(corruption_detected); + ip += llhSize; + } + { + size_t const ofhSize = ZSTD_buildSeqTable(dctx->entropy.OFTable, &dctx->OFTptr, OFtype, MaxOff, OffFSELog, ip, iend - ip, + OF_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); + if (ZSTD_isError(ofhSize)) + return ERROR(corruption_detected); + ip += ofhSize; + } + { + size_t const mlhSize = ZSTD_buildSeqTable(dctx->entropy.MLTable, &dctx->MLTptr, MLtype, MaxML, MLFSELog, ip, iend - ip, + ML_defaultDTable, dctx->fseEntropy, dctx->entropy.workspace, sizeof(dctx->entropy.workspace)); + if (ZSTD_isError(mlhSize)) + return ERROR(corruption_detected); + ip += mlhSize; + } + } + + return ip - istart; +} + +typedef struct { + size_t litLength; + size_t matchLength; + size_t offset; + const BYTE *match; +} seq_t; + +typedef struct { + BIT_DStream_t DStream; + FSE_DState_t stateLL; + FSE_DState_t stateOffb; + FSE_DState_t stateML; + size_t prevOffset[ZSTD_REP_NUM]; + const BYTE *base; + size_t pos; + uPtrDiff gotoDict; +} seqState_t; + +FORCE_NOINLINE +size_t ZSTD_execSequenceLast7(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, + const BYTE *const vBase, const BYTE *const dictEnd) +{ + BYTE *const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE *const iLitEnd = *litPtr + sequence.litLength; + const BYTE *match = oLitEnd - sequence.offset; + + /* check */ + if (oMatchEnd > oend) + return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) + return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd <= oend_w) + return ERROR(GENERIC); /* Precondition */ + + /* copy literals */ + if (op < oend_w) { + ZSTD_wildcopy(op, *litPtr, oend_w - op); + *litPtr += oend_w - op; + op = oend_w; + } + while (op < oLitEnd) + *op++ = *(*litPtr)++; + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) + return ERROR(corruption_detected); + match = dictEnd - (base - match); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currPrefixSegment */ + { + size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + } + } + while (op < oMatchEnd) + *op++ = *match++; + return sequenceLength; +} + +static seq_t ZSTD_decodeSequence(seqState_t *seqState) +{ + seq_t seq; + + U32 const llCode = FSE_peekSymbol(&seqState->stateLL); + U32 const mlCode = FSE_peekSymbol(&seqState->stateML); + U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ + + U32 const llBits = LL_bits[llCode]; + U32 const mlBits = ML_bits[mlCode]; + U32 const ofBits = ofCode; + U32 const totalBits = llBits + mlBits + ofBits; + + static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, + 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000}; + + static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, + 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41, + 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003}; + + static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD, + 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, + 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD}; + + /* sequence */ + { + size_t offset; + if (!ofCode) + offset = 0; + else { + offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); + } + + if (ofCode <= 1) { + offset += (llCode == 0); + if (offset) { + size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; + temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ + if (offset != 1) + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset = temp; + } else { + offset = seqState->prevOffset[0]; + } + } else { + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset; + } + seq.offset = offset; + } + + seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() && (mlBits + llBits > 24)) + BIT_reloadDStream(&seqState->DStream); + + seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) + BIT_reloadDStream(&seqState->DStream); + + /* ANS state update */ + FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ + FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ + FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ + + seq.match = NULL; + + return seq; +} + +FORCE_INLINE +size_t ZSTD_execSequence(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, + const BYTE *const vBase, const BYTE *const dictEnd) +{ + BYTE *const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE *const iLitEnd = *litPtr + sequence.litLength; + const BYTE *match = oLitEnd - sequence.offset; + + /* check */ + if (oMatchEnd > oend) + return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) + return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd > oend_w) + return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); + + /* copy Literals */ + ZSTD_copy8(op, *litPtr); + if (sequence.litLength > 8) + ZSTD_wildcopy(op + 8, (*litPtr) + 8, + sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ + op = oLitEnd; + *litPtr = iLitEnd; /* update for next sequence */ + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) + return ERROR(corruption_detected); + match = dictEnd + (match - base); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currPrefixSegment */ + { + size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + if (op > oend_w || sequence.matchLength < MINMATCH) { + U32 i; + for (i = 0; i < sequence.matchLength; ++i) + op[i] = match[i]; + return sequenceLength; + } + } + } + /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ + + /* match within prefix */ + if (sequence.offset < 8) { + /* close range match, overlap */ + static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ + static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */ + int const sub2 = dec64table[sequence.offset]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[sequence.offset]; + ZSTD_copy4(op + 4, match); + match -= sub2; + } else { + ZSTD_copy8(op, match); + } + op += 8; + match += 8; + + if (oMatchEnd > oend - (16 - MINMATCH)) { + if (op < oend_w) { + ZSTD_wildcopy(op, match, oend_w - op); + match += oend_w - op; + op = oend_w; + } + while (op < oMatchEnd) + *op++ = *match++; + } else { + ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */ + } + return sequenceLength; +} + +static size_t ZSTD_decompressSequences(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize) +{ + const BYTE *ip = (const BYTE *)seqStart; + const BYTE *const iend = ip + seqSize; + BYTE *const ostart = (BYTE * const)dst; + BYTE *const oend = ostart + maxDstSize; + BYTE *op = ostart; + const BYTE *litPtr = dctx->litPtr; + const BYTE *const litEnd = litPtr + dctx->litSize; + const BYTE *const base = (const BYTE *)(dctx->base); + const BYTE *const vBase = (const BYTE *)(dctx->vBase); + const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd); + int nbSeq; + + /* Build Decoding Tables */ + { + size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); + if (ZSTD_isError(seqHSize)) + return seqHSize; + ip += seqHSize; + } + + /* Regen sequences */ + if (nbSeq) { + seqState_t seqState; + dctx->fseEntropy = 1; + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + seqState.prevOffset[i] = dctx->entropy.rep[i]; + } + CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected); + FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); + FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); + FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); + + for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && nbSeq;) { + nbSeq--; + { + seq_t const sequence = ZSTD_decodeSequence(&seqState); + size_t const oneSeqSize = ZSTD_execSequence(op, oend, sequence, &litPtr, litEnd, base, vBase, dictEnd); + if (ZSTD_isError(oneSeqSize)) + return oneSeqSize; + op += oneSeqSize; + } + } + + /* check if reached exact end */ + if (nbSeq) + return ERROR(corruption_detected); + /* save reps for next block */ + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); + } + } + + /* last literal segment */ + { + size_t const lastLLSize = litEnd - litPtr; + if (lastLLSize > (size_t)(oend - op)) + return ERROR(dstSize_tooSmall); + memcpy(op, litPtr, lastLLSize); + op += lastLLSize; + } + + return op - ostart; +} + +FORCE_INLINE seq_t ZSTD_decodeSequenceLong_generic(seqState_t *seqState, int const longOffsets) +{ + seq_t seq; + + U32 const llCode = FSE_peekSymbol(&seqState->stateLL); + U32 const mlCode = FSE_peekSymbol(&seqState->stateML); + U32 const ofCode = FSE_peekSymbol(&seqState->stateOffb); /* <= maxOff, by table construction */ + + U32 const llBits = LL_bits[llCode]; + U32 const mlBits = ML_bits[mlCode]; + U32 const ofBits = ofCode; + U32 const totalBits = llBits + mlBits + ofBits; + + static const U32 LL_base[MaxLL + 1] = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, + 20, 22, 24, 28, 32, 40, 48, 64, 0x80, 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000, 0x8000, 0x10000}; + + static const U32 ML_base[MaxML + 1] = {3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, + 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 37, 39, 41, + 43, 47, 51, 59, 67, 83, 99, 0x83, 0x103, 0x203, 0x403, 0x803, 0x1003, 0x2003, 0x4003, 0x8003, 0x10003}; + + static const U32 OF_base[MaxOff + 1] = {0, 1, 1, 5, 0xD, 0x1D, 0x3D, 0x7D, 0xFD, 0x1FD, + 0x3FD, 0x7FD, 0xFFD, 0x1FFD, 0x3FFD, 0x7FFD, 0xFFFD, 0x1FFFD, 0x3FFFD, 0x7FFFD, + 0xFFFFD, 0x1FFFFD, 0x3FFFFD, 0x7FFFFD, 0xFFFFFD, 0x1FFFFFD, 0x3FFFFFD, 0x7FFFFFD, 0xFFFFFFD}; + + /* sequence */ + { + size_t offset; + if (!ofCode) + offset = 0; + else { + if (longOffsets) { + int const extraBits = ofBits - MIN(ofBits, STREAM_ACCUMULATOR_MIN); + offset = OF_base[ofCode] + (BIT_readBitsFast(&seqState->DStream, ofBits - extraBits) << extraBits); + if (ZSTD_32bits() || extraBits) + BIT_reloadDStream(&seqState->DStream); + if (extraBits) + offset += BIT_readBitsFast(&seqState->DStream, extraBits); + } else { + offset = OF_base[ofCode] + BIT_readBitsFast(&seqState->DStream, ofBits); /* <= (ZSTD_WINDOWLOG_MAX-1) bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); + } + } + + if (ofCode <= 1) { + offset += (llCode == 0); + if (offset) { + size_t temp = (offset == 3) ? seqState->prevOffset[0] - 1 : seqState->prevOffset[offset]; + temp += !temp; /* 0 is not valid; input is corrupted; force offset to 1 */ + if (offset != 1) + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset = temp; + } else { + offset = seqState->prevOffset[0]; + } + } else { + seqState->prevOffset[2] = seqState->prevOffset[1]; + seqState->prevOffset[1] = seqState->prevOffset[0]; + seqState->prevOffset[0] = offset; + } + seq.offset = offset; + } + + seq.matchLength = ML_base[mlCode] + ((mlCode > 31) ? BIT_readBitsFast(&seqState->DStream, mlBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() && (mlBits + llBits > 24)) + BIT_reloadDStream(&seqState->DStream); + + seq.litLength = LL_base[llCode] + ((llCode > 15) ? BIT_readBitsFast(&seqState->DStream, llBits) : 0); /* <= 16 bits */ + if (ZSTD_32bits() || (totalBits > 64 - 7 - (LLFSELog + MLFSELog + OffFSELog))) + BIT_reloadDStream(&seqState->DStream); + + { + size_t const pos = seqState->pos + seq.litLength; + seq.match = seqState->base + pos - seq.offset; /* single memory segment */ + if (seq.offset > pos) + seq.match += seqState->gotoDict; /* separate memory segment */ + seqState->pos = pos + seq.matchLength; + } + + /* ANS state update */ + FSE_updateState(&seqState->stateLL, &seqState->DStream); /* <= 9 bits */ + FSE_updateState(&seqState->stateML, &seqState->DStream); /* <= 9 bits */ + if (ZSTD_32bits()) + BIT_reloadDStream(&seqState->DStream); /* <= 18 bits */ + FSE_updateState(&seqState->stateOffb, &seqState->DStream); /* <= 8 bits */ + + return seq; +} + +static seq_t ZSTD_decodeSequenceLong(seqState_t *seqState, unsigned const windowSize) +{ + if (ZSTD_highbit32(windowSize) > STREAM_ACCUMULATOR_MIN) { + return ZSTD_decodeSequenceLong_generic(seqState, 1); + } else { + return ZSTD_decodeSequenceLong_generic(seqState, 0); + } +} + +FORCE_INLINE +size_t ZSTD_execSequenceLong(BYTE *op, BYTE *const oend, seq_t sequence, const BYTE **litPtr, const BYTE *const litLimit, const BYTE *const base, + const BYTE *const vBase, const BYTE *const dictEnd) +{ + BYTE *const oLitEnd = op + sequence.litLength; + size_t const sequenceLength = sequence.litLength + sequence.matchLength; + BYTE *const oMatchEnd = op + sequenceLength; /* risk : address space overflow (32-bits) */ + BYTE *const oend_w = oend - WILDCOPY_OVERLENGTH; + const BYTE *const iLitEnd = *litPtr + sequence.litLength; + const BYTE *match = sequence.match; + + /* check */ + if (oMatchEnd > oend) + return ERROR(dstSize_tooSmall); /* last match must start at a minimum distance of WILDCOPY_OVERLENGTH from oend */ + if (iLitEnd > litLimit) + return ERROR(corruption_detected); /* over-read beyond lit buffer */ + if (oLitEnd > oend_w) + return ZSTD_execSequenceLast7(op, oend, sequence, litPtr, litLimit, base, vBase, dictEnd); + + /* copy Literals */ + ZSTD_copy8(op, *litPtr); + if (sequence.litLength > 8) + ZSTD_wildcopy(op + 8, (*litPtr) + 8, + sequence.litLength - 8); /* note : since oLitEnd <= oend-WILDCOPY_OVERLENGTH, no risk of overwrite beyond oend */ + op = oLitEnd; + *litPtr = iLitEnd; /* update for next sequence */ + + /* copy Match */ + if (sequence.offset > (size_t)(oLitEnd - base)) { + /* offset beyond prefix */ + if (sequence.offset > (size_t)(oLitEnd - vBase)) + return ERROR(corruption_detected); + if (match + sequence.matchLength <= dictEnd) { + memmove(oLitEnd, match, sequence.matchLength); + return sequenceLength; + } + /* span extDict & currPrefixSegment */ + { + size_t const length1 = dictEnd - match; + memmove(oLitEnd, match, length1); + op = oLitEnd + length1; + sequence.matchLength -= length1; + match = base; + if (op > oend_w || sequence.matchLength < MINMATCH) { + U32 i; + for (i = 0; i < sequence.matchLength; ++i) + op[i] = match[i]; + return sequenceLength; + } + } + } + /* Requirement: op <= oend_w && sequence.matchLength >= MINMATCH */ + + /* match within prefix */ + if (sequence.offset < 8) { + /* close range match, overlap */ + static const U32 dec32table[] = {0, 1, 2, 1, 4, 4, 4, 4}; /* added */ + static const int dec64table[] = {8, 8, 8, 7, 8, 9, 10, 11}; /* subtracted */ + int const sub2 = dec64table[sequence.offset]; + op[0] = match[0]; + op[1] = match[1]; + op[2] = match[2]; + op[3] = match[3]; + match += dec32table[sequence.offset]; + ZSTD_copy4(op + 4, match); + match -= sub2; + } else { + ZSTD_copy8(op, match); + } + op += 8; + match += 8; + + if (oMatchEnd > oend - (16 - MINMATCH)) { + if (op < oend_w) { + ZSTD_wildcopy(op, match, oend_w - op); + match += oend_w - op; + op = oend_w; + } + while (op < oMatchEnd) + *op++ = *match++; + } else { + ZSTD_wildcopy(op, match, (ptrdiff_t)sequence.matchLength - 8); /* works even if matchLength < 8 */ + } + return sequenceLength; +} + +static size_t ZSTD_decompressSequencesLong(ZSTD_DCtx *dctx, void *dst, size_t maxDstSize, const void *seqStart, size_t seqSize) +{ + const BYTE *ip = (const BYTE *)seqStart; + const BYTE *const iend = ip + seqSize; + BYTE *const ostart = (BYTE * const)dst; + BYTE *const oend = ostart + maxDstSize; + BYTE *op = ostart; + const BYTE *litPtr = dctx->litPtr; + const BYTE *const litEnd = litPtr + dctx->litSize; + const BYTE *const base = (const BYTE *)(dctx->base); + const BYTE *const vBase = (const BYTE *)(dctx->vBase); + const BYTE *const dictEnd = (const BYTE *)(dctx->dictEnd); + unsigned const windowSize = dctx->fParams.windowSize; + int nbSeq; + + /* Build Decoding Tables */ + { + size_t const seqHSize = ZSTD_decodeSeqHeaders(dctx, &nbSeq, ip, seqSize); + if (ZSTD_isError(seqHSize)) + return seqHSize; + ip += seqHSize; + } + + /* Regen sequences */ + if (nbSeq) { +#define STORED_SEQS 4 +#define STOSEQ_MASK (STORED_SEQS - 1) +#define ADVANCED_SEQS 4 + seq_t *sequences = (seq_t *)dctx->entropy.workspace; + int const seqAdvance = MIN(nbSeq, ADVANCED_SEQS); + seqState_t seqState; + int seqNb; + ZSTD_STATIC_ASSERT(sizeof(dctx->entropy.workspace) >= sizeof(seq_t) * STORED_SEQS); + dctx->fseEntropy = 1; + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + seqState.prevOffset[i] = dctx->entropy.rep[i]; + } + seqState.base = base; + seqState.pos = (size_t)(op - base); + seqState.gotoDict = (uPtrDiff)dictEnd - (uPtrDiff)base; /* cast to avoid undefined behaviour */ + CHECK_E(BIT_initDStream(&seqState.DStream, ip, iend - ip), corruption_detected); + FSE_initDState(&seqState.stateLL, &seqState.DStream, dctx->LLTptr); + FSE_initDState(&seqState.stateOffb, &seqState.DStream, dctx->OFTptr); + FSE_initDState(&seqState.stateML, &seqState.DStream, dctx->MLTptr); + + /* prepare in advance */ + for (seqNb = 0; (BIT_reloadDStream(&seqState.DStream) <= BIT_DStream_completed) && seqNb < seqAdvance; seqNb++) { + sequences[seqNb] = ZSTD_decodeSequenceLong(&seqState, windowSize); + } + if (seqNb < seqAdvance) + return ERROR(corruption_detected); + + /* decode and decompress */ + for (; (BIT_reloadDStream(&(seqState.DStream)) <= BIT_DStream_completed) && seqNb < nbSeq; seqNb++) { + seq_t const sequence = ZSTD_decodeSequenceLong(&seqState, windowSize); + size_t const oneSeqSize = + ZSTD_execSequenceLong(op, oend, sequences[(seqNb - ADVANCED_SEQS) & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); + if (ZSTD_isError(oneSeqSize)) + return oneSeqSize; + ZSTD_PREFETCH(sequence.match); + sequences[seqNb & STOSEQ_MASK] = sequence; + op += oneSeqSize; + } + if (seqNb < nbSeq) + return ERROR(corruption_detected); + + /* finish queue */ + seqNb -= seqAdvance; + for (; seqNb < nbSeq; seqNb++) { + size_t const oneSeqSize = ZSTD_execSequenceLong(op, oend, sequences[seqNb & STOSEQ_MASK], &litPtr, litEnd, base, vBase, dictEnd); + if (ZSTD_isError(oneSeqSize)) + return oneSeqSize; + op += oneSeqSize; + } + + /* save reps for next block */ + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + dctx->entropy.rep[i] = (U32)(seqState.prevOffset[i]); + } + } + + /* last literal segment */ + { + size_t const lastLLSize = litEnd - litPtr; + if (lastLLSize > (size_t)(oend - op)) + return ERROR(dstSize_tooSmall); + memcpy(op, litPtr, lastLLSize); + op += lastLLSize; + } + + return op - ostart; +} + +static size_t ZSTD_decompressBlock_internal(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ /* blockType == blockCompressed */ + const BYTE *ip = (const BYTE *)src; + + if (srcSize >= ZSTD_BLOCKSIZE_ABSOLUTEMAX) + return ERROR(srcSize_wrong); + + /* Decode literals section */ + { + size_t const litCSize = ZSTD_decodeLiteralsBlock(dctx, src, srcSize); + if (ZSTD_isError(litCSize)) + return litCSize; + ip += litCSize; + srcSize -= litCSize; + } + if (sizeof(size_t) > 4) /* do not enable prefetching on 32-bits x86, as it's performance detrimental */ + /* likely because of register pressure */ + /* if that's the correct cause, then 32-bits ARM should be affected differently */ + /* it would be good to test this on ARM real hardware, to see if prefetch version improves speed */ + if (dctx->fParams.windowSize > (1 << 23)) + return ZSTD_decompressSequencesLong(dctx, dst, dstCapacity, ip, srcSize); + return ZSTD_decompressSequences(dctx, dst, dstCapacity, ip, srcSize); +} + +static void ZSTD_checkContinuity(ZSTD_DCtx *dctx, const void *dst) +{ + if (dst != dctx->previousDstEnd) { /* not contiguous */ + dctx->dictEnd = dctx->previousDstEnd; + dctx->vBase = (const char *)dst - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base)); + dctx->base = dst; + dctx->previousDstEnd = dst; + } +} + +size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t dSize; + ZSTD_checkContinuity(dctx, dst); + dSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); + dctx->previousDstEnd = (char *)dst + dSize; + return dSize; +} + +/** ZSTD_insertBlock() : + insert `src` block into `dctx` history. Useful to track uncompressed blocks. */ +size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart, size_t blockSize) +{ + ZSTD_checkContinuity(dctx, blockStart); + dctx->previousDstEnd = (const char *)blockStart + blockSize; + return blockSize; +} + +size_t ZSTD_generateNxBytes(void *dst, size_t dstCapacity, BYTE byte, size_t length) +{ + if (length > dstCapacity) + return ERROR(dstSize_tooSmall); + memset(dst, byte, length); + return length; +} + +/** ZSTD_findFrameCompressedSize() : + * compatible with legacy mode + * `src` must point to the start of a ZSTD frame, ZSTD legacy frame, or skippable frame + * `srcSize` must be at least as large as the frame contained + * @return : the compressed size of the frame starting at `src` */ +size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize) +{ + if (srcSize >= ZSTD_skippableHeaderSize && (ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + return ZSTD_skippableHeaderSize + ZSTD_readLE32((const BYTE *)src + 4); + } else { + const BYTE *ip = (const BYTE *)src; + const BYTE *const ipstart = ip; + size_t remainingSize = srcSize; + ZSTD_frameParams fParams; + + size_t const headerSize = ZSTD_frameHeaderSize(ip, remainingSize); + if (ZSTD_isError(headerSize)) + return headerSize; + + /* Frame Header */ + { + size_t const ret = ZSTD_getFrameParams(&fParams, ip, remainingSize); + if (ZSTD_isError(ret)) + return ret; + if (ret > 0) + return ERROR(srcSize_wrong); + } + + ip += headerSize; + remainingSize -= headerSize; + + /* Loop on each block */ + while (1) { + blockProperties_t blockProperties; + size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); + if (ZSTD_isError(cBlockSize)) + return cBlockSize; + + if (ZSTD_blockHeaderSize + cBlockSize > remainingSize) + return ERROR(srcSize_wrong); + + ip += ZSTD_blockHeaderSize + cBlockSize; + remainingSize -= ZSTD_blockHeaderSize + cBlockSize; + + if (blockProperties.lastBlock) + break; + } + + if (fParams.checksumFlag) { /* Frame content checksum */ + if (remainingSize < 4) + return ERROR(srcSize_wrong); + ip += 4; + remainingSize -= 4; + } + + return ip - ipstart; + } +} + +/*! ZSTD_decompressFrame() : +* @dctx must be properly initialized */ +static size_t ZSTD_decompressFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void **srcPtr, size_t *srcSizePtr) +{ + const BYTE *ip = (const BYTE *)(*srcPtr); + BYTE *const ostart = (BYTE * const)dst; + BYTE *const oend = ostart + dstCapacity; + BYTE *op = ostart; + size_t remainingSize = *srcSizePtr; + + /* check */ + if (remainingSize < ZSTD_frameHeaderSize_min + ZSTD_blockHeaderSize) + return ERROR(srcSize_wrong); + + /* Frame Header */ + { + size_t const frameHeaderSize = ZSTD_frameHeaderSize(ip, ZSTD_frameHeaderSize_prefix); + if (ZSTD_isError(frameHeaderSize)) + return frameHeaderSize; + if (remainingSize < frameHeaderSize + ZSTD_blockHeaderSize) + return ERROR(srcSize_wrong); + CHECK_F(ZSTD_decodeFrameHeader(dctx, ip, frameHeaderSize)); + ip += frameHeaderSize; + remainingSize -= frameHeaderSize; + } + + /* Loop on each block */ + while (1) { + size_t decodedSize; + blockProperties_t blockProperties; + size_t const cBlockSize = ZSTD_getcBlockSize(ip, remainingSize, &blockProperties); + if (ZSTD_isError(cBlockSize)) + return cBlockSize; + + ip += ZSTD_blockHeaderSize; + remainingSize -= ZSTD_blockHeaderSize; + if (cBlockSize > remainingSize) + return ERROR(srcSize_wrong); + + switch (blockProperties.blockType) { + case bt_compressed: decodedSize = ZSTD_decompressBlock_internal(dctx, op, oend - op, ip, cBlockSize); break; + case bt_raw: decodedSize = ZSTD_copyRawBlock(op, oend - op, ip, cBlockSize); break; + case bt_rle: decodedSize = ZSTD_generateNxBytes(op, oend - op, *ip, blockProperties.origSize); break; + case bt_reserved: + default: return ERROR(corruption_detected); + } + + if (ZSTD_isError(decodedSize)) + return decodedSize; + if (dctx->fParams.checksumFlag) + xxh64_update(&dctx->xxhState, op, decodedSize); + op += decodedSize; + ip += cBlockSize; + remainingSize -= cBlockSize; + if (blockProperties.lastBlock) + break; + } + + if (dctx->fParams.checksumFlag) { /* Frame content checksum verification */ + U32 const checkCalc = (U32)xxh64_digest(&dctx->xxhState); + U32 checkRead; + if (remainingSize < 4) + return ERROR(checksum_wrong); + checkRead = ZSTD_readLE32(ip); + if (checkRead != checkCalc) + return ERROR(checksum_wrong); + ip += 4; + remainingSize -= 4; + } + + /* Allow caller to get size read */ + *srcPtr = ip; + *srcSizePtr = remainingSize; + return op - ostart; +} + +static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict); +static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict); + +static size_t ZSTD_decompressMultiFrame(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize, + const ZSTD_DDict *ddict) +{ + void *const dststart = dst; + + if (ddict) { + if (dict) { + /* programmer error, these two cases should be mutually exclusive */ + return ERROR(GENERIC); + } + + dict = ZSTD_DDictDictContent(ddict); + dictSize = ZSTD_DDictDictSize(ddict); + } + + while (srcSize >= ZSTD_frameHeaderSize_prefix) { + U32 magicNumber; + + magicNumber = ZSTD_readLE32(src); + if (magicNumber != ZSTD_MAGICNUMBER) { + if ((magicNumber & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { + size_t skippableSize; + if (srcSize < ZSTD_skippableHeaderSize) + return ERROR(srcSize_wrong); + skippableSize = ZSTD_readLE32((const BYTE *)src + 4) + ZSTD_skippableHeaderSize; + if (srcSize < skippableSize) { + return ERROR(srcSize_wrong); + } + + src = (const BYTE *)src + skippableSize; + srcSize -= skippableSize; + continue; + } else { + return ERROR(prefix_unknown); + } + } + + if (ddict) { + /* we were called from ZSTD_decompress_usingDDict */ + ZSTD_refDDict(dctx, ddict); + } else { + /* this will initialize correctly with no dict if dict == NULL, so + * use this in all cases but ddict */ + CHECK_F(ZSTD_decompressBegin_usingDict(dctx, dict, dictSize)); + } + ZSTD_checkContinuity(dctx, dst); + + { + const size_t res = ZSTD_decompressFrame(dctx, dst, dstCapacity, &src, &srcSize); + if (ZSTD_isError(res)) + return res; + /* don't need to bounds check this, ZSTD_decompressFrame will have + * already */ + dst = (BYTE *)dst + res; + dstCapacity -= res; + } + } + + if (srcSize) + return ERROR(srcSize_wrong); /* input not entirely consumed */ + + return (BYTE *)dst - (BYTE *)dststart; +} + +size_t ZSTD_decompress_usingDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const void *dict, size_t dictSize) +{ + return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, dict, dictSize, NULL); +} + +size_t ZSTD_decompressDCtx(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + return ZSTD_decompress_usingDict(dctx, dst, dstCapacity, src, srcSize, NULL, 0); +} + +/*-************************************** +* Advanced Streaming Decompression API +* Bufferless and synchronous +****************************************/ +size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx) { return dctx->expected; } + +ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx) +{ + switch (dctx->stage) { + default: /* should not happen */ + case ZSTDds_getFrameHeaderSize: + case ZSTDds_decodeFrameHeader: return ZSTDnit_frameHeader; + case ZSTDds_decodeBlockHeader: return ZSTDnit_blockHeader; + case ZSTDds_decompressBlock: return ZSTDnit_block; + case ZSTDds_decompressLastBlock: return ZSTDnit_lastBlock; + case ZSTDds_checkChecksum: return ZSTDnit_checksum; + case ZSTDds_decodeSkippableHeader: + case ZSTDds_skipFrame: return ZSTDnit_skippableFrame; + } +} + +int ZSTD_isSkipFrame(ZSTD_DCtx *dctx) { return dctx->stage == ZSTDds_skipFrame; } /* for zbuff */ + +/** ZSTD_decompressContinue() : +* @return : nb of bytes generated into `dst` (necessarily <= `dstCapacity) +* or an error code, which can be tested using ZSTD_isError() */ +size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + /* Sanity check */ + if (srcSize != dctx->expected) + return ERROR(srcSize_wrong); + if (dstCapacity) + ZSTD_checkContinuity(dctx, dst); + + switch (dctx->stage) { + case ZSTDds_getFrameHeaderSize: + if (srcSize != ZSTD_frameHeaderSize_prefix) + return ERROR(srcSize_wrong); /* impossible */ + if ((ZSTD_readLE32(src) & 0xFFFFFFF0U) == ZSTD_MAGIC_SKIPPABLE_START) { /* skippable frame */ + memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); + dctx->expected = ZSTD_skippableHeaderSize - ZSTD_frameHeaderSize_prefix; /* magic number + skippable frame length */ + dctx->stage = ZSTDds_decodeSkippableHeader; + return 0; + } + dctx->headerSize = ZSTD_frameHeaderSize(src, ZSTD_frameHeaderSize_prefix); + if (ZSTD_isError(dctx->headerSize)) + return dctx->headerSize; + memcpy(dctx->headerBuffer, src, ZSTD_frameHeaderSize_prefix); + if (dctx->headerSize > ZSTD_frameHeaderSize_prefix) { + dctx->expected = dctx->headerSize - ZSTD_frameHeaderSize_prefix; + dctx->stage = ZSTDds_decodeFrameHeader; + return 0; + } + dctx->expected = 0; /* not necessary to copy more */ + /* fall through */ + + case ZSTDds_decodeFrameHeader: + memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); + CHECK_F(ZSTD_decodeFrameHeader(dctx, dctx->headerBuffer, dctx->headerSize)); + dctx->expected = ZSTD_blockHeaderSize; + dctx->stage = ZSTDds_decodeBlockHeader; + return 0; + + case ZSTDds_decodeBlockHeader: { + blockProperties_t bp; + size_t const cBlockSize = ZSTD_getcBlockSize(src, ZSTD_blockHeaderSize, &bp); + if (ZSTD_isError(cBlockSize)) + return cBlockSize; + dctx->expected = cBlockSize; + dctx->bType = bp.blockType; + dctx->rleSize = bp.origSize; + if (cBlockSize) { + dctx->stage = bp.lastBlock ? ZSTDds_decompressLastBlock : ZSTDds_decompressBlock; + return 0; + } + /* empty block */ + if (bp.lastBlock) { + if (dctx->fParams.checksumFlag) { + dctx->expected = 4; + dctx->stage = ZSTDds_checkChecksum; + } else { + dctx->expected = 0; /* end of frame */ + dctx->stage = ZSTDds_getFrameHeaderSize; + } + } else { + dctx->expected = 3; /* go directly to next header */ + dctx->stage = ZSTDds_decodeBlockHeader; + } + return 0; + } + case ZSTDds_decompressLastBlock: + case ZSTDds_decompressBlock: { + size_t rSize; + switch (dctx->bType) { + case bt_compressed: rSize = ZSTD_decompressBlock_internal(dctx, dst, dstCapacity, src, srcSize); break; + case bt_raw: rSize = ZSTD_copyRawBlock(dst, dstCapacity, src, srcSize); break; + case bt_rle: rSize = ZSTD_setRleBlock(dst, dstCapacity, src, srcSize, dctx->rleSize); break; + case bt_reserved: /* should never happen */ + default: return ERROR(corruption_detected); + } + if (ZSTD_isError(rSize)) + return rSize; + if (dctx->fParams.checksumFlag) + xxh64_update(&dctx->xxhState, dst, rSize); + + if (dctx->stage == ZSTDds_decompressLastBlock) { /* end of frame */ + if (dctx->fParams.checksumFlag) { /* another round for frame checksum */ + dctx->expected = 4; + dctx->stage = ZSTDds_checkChecksum; + } else { + dctx->expected = 0; /* ends here */ + dctx->stage = ZSTDds_getFrameHeaderSize; + } + } else { + dctx->stage = ZSTDds_decodeBlockHeader; + dctx->expected = ZSTD_blockHeaderSize; + dctx->previousDstEnd = (char *)dst + rSize; + } + return rSize; + } + case ZSTDds_checkChecksum: { + U32 const h32 = (U32)xxh64_digest(&dctx->xxhState); + U32 const check32 = ZSTD_readLE32(src); /* srcSize == 4, guaranteed by dctx->expected */ + if (check32 != h32) + return ERROR(checksum_wrong); + dctx->expected = 0; + dctx->stage = ZSTDds_getFrameHeaderSize; + return 0; + } + case ZSTDds_decodeSkippableHeader: { + memcpy(dctx->headerBuffer + ZSTD_frameHeaderSize_prefix, src, dctx->expected); + dctx->expected = ZSTD_readLE32(dctx->headerBuffer + 4); + dctx->stage = ZSTDds_skipFrame; + return 0; + } + case ZSTDds_skipFrame: { + dctx->expected = 0; + dctx->stage = ZSTDds_getFrameHeaderSize; + return 0; + } + default: + return ERROR(GENERIC); /* impossible */ + } +} + +static size_t ZSTD_refDictContent(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) +{ + dctx->dictEnd = dctx->previousDstEnd; + dctx->vBase = (const char *)dict - ((const char *)(dctx->previousDstEnd) - (const char *)(dctx->base)); + dctx->base = dict; + dctx->previousDstEnd = (const char *)dict + dictSize; + return 0; +} + +/* ZSTD_loadEntropy() : + * dict : must point at beginning of a valid zstd dictionary + * @return : size of entropy tables read */ +static size_t ZSTD_loadEntropy(ZSTD_entropyTables_t *entropy, const void *const dict, size_t const dictSize) +{ + const BYTE *dictPtr = (const BYTE *)dict; + const BYTE *const dictEnd = dictPtr + dictSize; + + if (dictSize <= 8) + return ERROR(dictionary_corrupted); + dictPtr += 8; /* skip header = magic + dictID */ + + { + size_t const hSize = HUF_readDTableX4_wksp(entropy->hufTable, dictPtr, dictEnd - dictPtr, entropy->workspace, sizeof(entropy->workspace)); + if (HUF_isError(hSize)) + return ERROR(dictionary_corrupted); + dictPtr += hSize; + } + + { + short offcodeNCount[MaxOff + 1]; + U32 offcodeMaxValue = MaxOff, offcodeLog; + size_t const offcodeHeaderSize = FSE_readNCount(offcodeNCount, &offcodeMaxValue, &offcodeLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(offcodeHeaderSize)) + return ERROR(dictionary_corrupted); + if (offcodeLog > OffFSELog) + return ERROR(dictionary_corrupted); + CHECK_E(FSE_buildDTable_wksp(entropy->OFTable, offcodeNCount, offcodeMaxValue, offcodeLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); + dictPtr += offcodeHeaderSize; + } + + { + short matchlengthNCount[MaxML + 1]; + unsigned matchlengthMaxValue = MaxML, matchlengthLog; + size_t const matchlengthHeaderSize = FSE_readNCount(matchlengthNCount, &matchlengthMaxValue, &matchlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(matchlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (matchlengthLog > MLFSELog) + return ERROR(dictionary_corrupted); + CHECK_E(FSE_buildDTable_wksp(entropy->MLTable, matchlengthNCount, matchlengthMaxValue, matchlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); + dictPtr += matchlengthHeaderSize; + } + + { + short litlengthNCount[MaxLL + 1]; + unsigned litlengthMaxValue = MaxLL, litlengthLog; + size_t const litlengthHeaderSize = FSE_readNCount(litlengthNCount, &litlengthMaxValue, &litlengthLog, dictPtr, dictEnd - dictPtr); + if (FSE_isError(litlengthHeaderSize)) + return ERROR(dictionary_corrupted); + if (litlengthLog > LLFSELog) + return ERROR(dictionary_corrupted); + CHECK_E(FSE_buildDTable_wksp(entropy->LLTable, litlengthNCount, litlengthMaxValue, litlengthLog, entropy->workspace, sizeof(entropy->workspace)), dictionary_corrupted); + dictPtr += litlengthHeaderSize; + } + + if (dictPtr + 12 > dictEnd) + return ERROR(dictionary_corrupted); + { + int i; + size_t const dictContentSize = (size_t)(dictEnd - (dictPtr + 12)); + for (i = 0; i < 3; i++) { + U32 const rep = ZSTD_readLE32(dictPtr); + dictPtr += 4; + if (rep == 0 || rep >= dictContentSize) + return ERROR(dictionary_corrupted); + entropy->rep[i] = rep; + } + } + + return dictPtr - (const BYTE *)dict; +} + +static size_t ZSTD_decompress_insertDictionary(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) +{ + if (dictSize < 8) + return ZSTD_refDictContent(dctx, dict, dictSize); + { + U32 const magic = ZSTD_readLE32(dict); + if (magic != ZSTD_DICT_MAGIC) { + return ZSTD_refDictContent(dctx, dict, dictSize); /* pure content mode */ + } + } + dctx->dictID = ZSTD_readLE32((const char *)dict + 4); + + /* load entropy tables */ + { + size_t const eSize = ZSTD_loadEntropy(&dctx->entropy, dict, dictSize); + if (ZSTD_isError(eSize)) + return ERROR(dictionary_corrupted); + dict = (const char *)dict + eSize; + dictSize -= eSize; + } + dctx->litEntropy = dctx->fseEntropy = 1; + + /* reference dictionary content */ + return ZSTD_refDictContent(dctx, dict, dictSize); +} + +size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict, size_t dictSize) +{ + CHECK_F(ZSTD_decompressBegin(dctx)); + if (dict && dictSize) + CHECK_E(ZSTD_decompress_insertDictionary(dctx, dict, dictSize), dictionary_corrupted); + return 0; +} + +/* ====== ZSTD_DDict ====== */ + +struct ZSTD_DDict_s { + void *dictBuffer; + const void *dictContent; + size_t dictSize; + ZSTD_entropyTables_t entropy; + U32 dictID; + U32 entropyPresent; + ZSTD_customMem cMem; +}; /* typedef'd to ZSTD_DDict within "zstd.h" */ + +size_t ZSTD_DDictWorkspaceBound(void) { return ZSTD_ALIGN(sizeof(ZSTD_stack)) + ZSTD_ALIGN(sizeof(ZSTD_DDict)); } + +static const void *ZSTD_DDictDictContent(const ZSTD_DDict *ddict) { return ddict->dictContent; } + +static size_t ZSTD_DDictDictSize(const ZSTD_DDict *ddict) { return ddict->dictSize; } + +static void ZSTD_refDDict(ZSTD_DCtx *dstDCtx, const ZSTD_DDict *ddict) +{ + ZSTD_decompressBegin(dstDCtx); /* init */ + if (ddict) { /* support refDDict on NULL */ + dstDCtx->dictID = ddict->dictID; + dstDCtx->base = ddict->dictContent; + dstDCtx->vBase = ddict->dictContent; + dstDCtx->dictEnd = (const BYTE *)ddict->dictContent + ddict->dictSize; + dstDCtx->previousDstEnd = dstDCtx->dictEnd; + if (ddict->entropyPresent) { + dstDCtx->litEntropy = 1; + dstDCtx->fseEntropy = 1; + dstDCtx->LLTptr = ddict->entropy.LLTable; + dstDCtx->MLTptr = ddict->entropy.MLTable; + dstDCtx->OFTptr = ddict->entropy.OFTable; + dstDCtx->HUFptr = ddict->entropy.hufTable; + dstDCtx->entropy.rep[0] = ddict->entropy.rep[0]; + dstDCtx->entropy.rep[1] = ddict->entropy.rep[1]; + dstDCtx->entropy.rep[2] = ddict->entropy.rep[2]; + } else { + dstDCtx->litEntropy = 0; + dstDCtx->fseEntropy = 0; + } + } +} + +static size_t ZSTD_loadEntropy_inDDict(ZSTD_DDict *ddict) +{ + ddict->dictID = 0; + ddict->entropyPresent = 0; + if (ddict->dictSize < 8) + return 0; + { + U32 const magic = ZSTD_readLE32(ddict->dictContent); + if (magic != ZSTD_DICT_MAGIC) + return 0; /* pure content mode */ + } + ddict->dictID = ZSTD_readLE32((const char *)ddict->dictContent + 4); + + /* load entropy tables */ + CHECK_E(ZSTD_loadEntropy(&ddict->entropy, ddict->dictContent, ddict->dictSize), dictionary_corrupted); + ddict->entropyPresent = 1; + return 0; +} + +static ZSTD_DDict *ZSTD_createDDict_advanced(const void *dict, size_t dictSize, unsigned byReference, ZSTD_customMem customMem) +{ + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + { + ZSTD_DDict *const ddict = (ZSTD_DDict *)ZSTD_malloc(sizeof(ZSTD_DDict), customMem); + if (!ddict) + return NULL; + ddict->cMem = customMem; + + if ((byReference) || (!dict) || (!dictSize)) { + ddict->dictBuffer = NULL; + ddict->dictContent = dict; + } else { + void *const internalBuffer = ZSTD_malloc(dictSize, customMem); + if (!internalBuffer) { + ZSTD_freeDDict(ddict); + return NULL; + } + memcpy(internalBuffer, dict, dictSize); + ddict->dictBuffer = internalBuffer; + ddict->dictContent = internalBuffer; + } + ddict->dictSize = dictSize; + ddict->entropy.hufTable[0] = (HUF_DTable)((HufLog)*0x1000001); /* cover both little and big endian */ + /* parse dictionary content */ + { + size_t const errorCode = ZSTD_loadEntropy_inDDict(ddict); + if (ZSTD_isError(errorCode)) { + ZSTD_freeDDict(ddict); + return NULL; + } + } + + return ddict; + } +} + +/*! ZSTD_initDDict() : +* Create a digested dictionary, to start decompression without startup delay. +* `dict` content is copied inside DDict. +* Consequently, `dict` can be released after `ZSTD_DDict` creation */ +ZSTD_DDict *ZSTD_initDDict(const void *dict, size_t dictSize, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + return ZSTD_createDDict_advanced(dict, dictSize, 1, stackMem); +} + +size_t ZSTD_freeDDict(ZSTD_DDict *ddict) +{ + if (ddict == NULL) + return 0; /* support free on NULL */ + { + ZSTD_customMem const cMem = ddict->cMem; + ZSTD_free(ddict->dictBuffer, cMem); + ZSTD_free(ddict, cMem); + return 0; + } +} + +/*! ZSTD_getDictID_fromDict() : + * Provides the dictID stored within dictionary. + * if @return == 0, the dictionary is not conformant with Zstandard specification. + * It can still be loaded, but as a content-only dictionary. */ +unsigned ZSTD_getDictID_fromDict(const void *dict, size_t dictSize) +{ + if (dictSize < 8) + return 0; + if (ZSTD_readLE32(dict) != ZSTD_DICT_MAGIC) + return 0; + return ZSTD_readLE32((const char *)dict + 4); +} + +/*! ZSTD_getDictID_fromDDict() : + * Provides the dictID of the dictionary loaded into `ddict`. + * If @return == 0, the dictionary is not conformant to Zstandard specification, or empty. + * Non-conformant dictionaries can still be loaded, but as content-only dictionaries. */ +unsigned ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict) +{ + if (ddict == NULL) + return 0; + return ZSTD_getDictID_fromDict(ddict->dictContent, ddict->dictSize); +} + +/*! ZSTD_getDictID_fromFrame() : + * Provides the dictID required to decompressed the frame stored within `src`. + * If @return == 0, the dictID could not be decoded. + * This could for one of the following reasons : + * - The frame does not require a dictionary to be decoded (most common case). + * - The frame was built with dictID intentionally removed. Whatever dictionary is necessary is a hidden information. + * Note : this use case also happens when using a non-conformant dictionary. + * - `srcSize` is too small, and as a result, the frame header could not be decoded (only possible if `srcSize < ZSTD_FRAMEHEADERSIZE_MAX`). + * - This is not a Zstandard frame. + * When identifying the exact failure cause, it's possible to used ZSTD_getFrameParams(), which will provide a more precise error code. */ +unsigned ZSTD_getDictID_fromFrame(const void *src, size_t srcSize) +{ + ZSTD_frameParams zfp = {0, 0, 0, 0}; + size_t const hError = ZSTD_getFrameParams(&zfp, src, srcSize); + if (ZSTD_isError(hError)) + return 0; + return zfp.dictID; +} + +/*! ZSTD_decompress_usingDDict() : +* Decompression using a pre-digested Dictionary +* Use dictionary without significant overhead. */ +size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, const void *src, size_t srcSize, const ZSTD_DDict *ddict) +{ + /* pass content and size in case legacy frames are encountered */ + return ZSTD_decompressMultiFrame(dctx, dst, dstCapacity, src, srcSize, NULL, 0, ddict); +} + +/*===================================== +* Streaming decompression +*====================================*/ + +typedef enum { zdss_init, zdss_loadHeader, zdss_read, zdss_load, zdss_flush } ZSTD_dStreamStage; + +/* *** Resource management *** */ +struct ZSTD_DStream_s { + ZSTD_DCtx *dctx; + ZSTD_DDict *ddictLocal; + const ZSTD_DDict *ddict; + ZSTD_frameParams fParams; + ZSTD_dStreamStage stage; + char *inBuff; + size_t inBuffSize; + size_t inPos; + size_t maxWindowSize; + char *outBuff; + size_t outBuffSize; + size_t outStart; + size_t outEnd; + size_t blockSize; + BYTE headerBuffer[ZSTD_FRAMEHEADERSIZE_MAX]; /* tmp buffer to store frame header */ + size_t lhSize; + ZSTD_customMem customMem; + void *legacyContext; + U32 previousLegacyVersion; + U32 legacyVersion; + U32 hostageByte; +}; /* typedef'd to ZSTD_DStream within "zstd.h" */ + +size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize) +{ + size_t const blockSize = MIN(maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); + size_t const inBuffSize = blockSize; + size_t const outBuffSize = maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; + return ZSTD_DCtxWorkspaceBound() + ZSTD_ALIGN(sizeof(ZSTD_DStream)) + ZSTD_ALIGN(inBuffSize) + ZSTD_ALIGN(outBuffSize); +} + +static ZSTD_DStream *ZSTD_createDStream_advanced(ZSTD_customMem customMem) +{ + ZSTD_DStream *zds; + + if (!customMem.customAlloc || !customMem.customFree) + return NULL; + + zds = (ZSTD_DStream *)ZSTD_malloc(sizeof(ZSTD_DStream), customMem); + if (zds == NULL) + return NULL; + memset(zds, 0, sizeof(ZSTD_DStream)); + memcpy(&zds->customMem, &customMem, sizeof(ZSTD_customMem)); + zds->dctx = ZSTD_createDCtx_advanced(customMem); + if (zds->dctx == NULL) { + ZSTD_freeDStream(zds); + return NULL; + } + zds->stage = zdss_init; + zds->maxWindowSize = ZSTD_MAXWINDOWSIZE_DEFAULT; + return zds; +} + +ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace, size_t workspaceSize) +{ + ZSTD_customMem const stackMem = ZSTD_initStack(workspace, workspaceSize); + ZSTD_DStream *zds = ZSTD_createDStream_advanced(stackMem); + if (!zds) { + return NULL; + } + + zds->maxWindowSize = maxWindowSize; + zds->stage = zdss_loadHeader; + zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; + ZSTD_freeDDict(zds->ddictLocal); + zds->ddictLocal = NULL; + zds->ddict = zds->ddictLocal; + zds->legacyVersion = 0; + zds->hostageByte = 0; + + { + size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); + size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; + + zds->inBuff = (char *)ZSTD_malloc(blockSize, zds->customMem); + zds->inBuffSize = blockSize; + zds->outBuff = (char *)ZSTD_malloc(neededOutSize, zds->customMem); + zds->outBuffSize = neededOutSize; + if (zds->inBuff == NULL || zds->outBuff == NULL) { + ZSTD_freeDStream(zds); + return NULL; + } + } + return zds; +} + +ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize, const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize) +{ + ZSTD_DStream *zds = ZSTD_initDStream(maxWindowSize, workspace, workspaceSize); + if (zds) { + zds->ddict = ddict; + } + return zds; +} + +size_t ZSTD_freeDStream(ZSTD_DStream *zds) +{ + if (zds == NULL) + return 0; /* support free on null */ + { + ZSTD_customMem const cMem = zds->customMem; + ZSTD_freeDCtx(zds->dctx); + zds->dctx = NULL; + ZSTD_freeDDict(zds->ddictLocal); + zds->ddictLocal = NULL; + ZSTD_free(zds->inBuff, cMem); + zds->inBuff = NULL; + ZSTD_free(zds->outBuff, cMem); + zds->outBuff = NULL; + ZSTD_free(zds, cMem); + return 0; + } +} + +/* *** Initialization *** */ + +size_t ZSTD_DStreamInSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX + ZSTD_blockHeaderSize; } +size_t ZSTD_DStreamOutSize(void) { return ZSTD_BLOCKSIZE_ABSOLUTEMAX; } + +size_t ZSTD_resetDStream(ZSTD_DStream *zds) +{ + zds->stage = zdss_loadHeader; + zds->lhSize = zds->inPos = zds->outStart = zds->outEnd = 0; + zds->legacyVersion = 0; + zds->hostageByte = 0; + return ZSTD_frameHeaderSize_prefix; +} + +/* ***** Decompression ***** */ + +ZSTD_STATIC size_t ZSTD_limitCopy(void *dst, size_t dstCapacity, const void *src, size_t srcSize) +{ + size_t const length = MIN(dstCapacity, srcSize); + memcpy(dst, src, length); + return length; +} + +size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, ZSTD_inBuffer *input) +{ + const char *const istart = (const char *)(input->src) + input->pos; + const char *const iend = (const char *)(input->src) + input->size; + const char *ip = istart; + char *const ostart = (char *)(output->dst) + output->pos; + char *const oend = (char *)(output->dst) + output->size; + char *op = ostart; + U32 someMoreWork = 1; + + while (someMoreWork) { + switch (zds->stage) { + case zdss_init: + ZSTD_resetDStream(zds); /* transparent reset on starting decoding a new frame */ + /* fall through */ + + case zdss_loadHeader: { + size_t const hSize = ZSTD_getFrameParams(&zds->fParams, zds->headerBuffer, zds->lhSize); + if (ZSTD_isError(hSize)) + return hSize; + if (hSize != 0) { /* need more input */ + size_t const toLoad = hSize - zds->lhSize; /* if hSize!=0, hSize > zds->lhSize */ + if (toLoad > (size_t)(iend - ip)) { /* not enough input to load full header */ + memcpy(zds->headerBuffer + zds->lhSize, ip, iend - ip); + zds->lhSize += iend - ip; + input->pos = input->size; + return (MAX(ZSTD_frameHeaderSize_min, hSize) - zds->lhSize) + + ZSTD_blockHeaderSize; /* remaining header bytes + next block header */ + } + memcpy(zds->headerBuffer + zds->lhSize, ip, toLoad); + zds->lhSize = hSize; + ip += toLoad; + break; + } + + /* check for single-pass mode opportunity */ + if (zds->fParams.frameContentSize && zds->fParams.windowSize /* skippable frame if == 0 */ + && (U64)(size_t)(oend - op) >= zds->fParams.frameContentSize) { + size_t const cSize = ZSTD_findFrameCompressedSize(istart, iend - istart); + if (cSize <= (size_t)(iend - istart)) { + size_t const decompressedSize = ZSTD_decompress_usingDDict(zds->dctx, op, oend - op, istart, cSize, zds->ddict); + if (ZSTD_isError(decompressedSize)) + return decompressedSize; + ip = istart + cSize; + op += decompressedSize; + zds->dctx->expected = 0; + zds->stage = zdss_init; + someMoreWork = 0; + break; + } + } + + /* Consume header */ + ZSTD_refDDict(zds->dctx, zds->ddict); + { + size_t const h1Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); /* == ZSTD_frameHeaderSize_prefix */ + CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer, h1Size)); + { + size_t const h2Size = ZSTD_nextSrcSizeToDecompress(zds->dctx); + CHECK_F(ZSTD_decompressContinue(zds->dctx, NULL, 0, zds->headerBuffer + h1Size, h2Size)); + } + } + + zds->fParams.windowSize = MAX(zds->fParams.windowSize, 1U << ZSTD_WINDOWLOG_ABSOLUTEMIN); + if (zds->fParams.windowSize > zds->maxWindowSize) + return ERROR(frameParameter_windowTooLarge); + + /* Buffers are preallocated, but double check */ + { + size_t const blockSize = MIN(zds->maxWindowSize, ZSTD_BLOCKSIZE_ABSOLUTEMAX); + size_t const neededOutSize = zds->maxWindowSize + blockSize + WILDCOPY_OVERLENGTH * 2; + if (zds->inBuffSize < blockSize) { + return ERROR(GENERIC); + } + if (zds->outBuffSize < neededOutSize) { + return ERROR(GENERIC); + } + zds->blockSize = blockSize; + } + zds->stage = zdss_read; + } + /* fall through */ + + case zdss_read: { + size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx); + if (neededInSize == 0) { /* end of frame */ + zds->stage = zdss_init; + someMoreWork = 0; + break; + } + if ((size_t)(iend - ip) >= neededInSize) { /* decode directly from src */ + const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx); + size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, + (isSkipFrame ? 0 : zds->outBuffSize - zds->outStart), ip, neededInSize); + if (ZSTD_isError(decodedSize)) + return decodedSize; + ip += neededInSize; + if (!decodedSize && !isSkipFrame) + break; /* this was just a header */ + zds->outEnd = zds->outStart + decodedSize; + zds->stage = zdss_flush; + break; + } + if (ip == iend) { + someMoreWork = 0; + break; + } /* no more input */ + zds->stage = zdss_load; + /* pass-through */ + } + /* fall through */ + + case zdss_load: { + size_t const neededInSize = ZSTD_nextSrcSizeToDecompress(zds->dctx); + size_t const toLoad = neededInSize - zds->inPos; /* should always be <= remaining space within inBuff */ + size_t loadedSize; + if (toLoad > zds->inBuffSize - zds->inPos) + return ERROR(corruption_detected); /* should never happen */ + loadedSize = ZSTD_limitCopy(zds->inBuff + zds->inPos, toLoad, ip, iend - ip); + ip += loadedSize; + zds->inPos += loadedSize; + if (loadedSize < toLoad) { + someMoreWork = 0; + break; + } /* not enough input, wait for more */ + + /* decode loaded input */ + { + const int isSkipFrame = ZSTD_isSkipFrame(zds->dctx); + size_t const decodedSize = ZSTD_decompressContinue(zds->dctx, zds->outBuff + zds->outStart, zds->outBuffSize - zds->outStart, + zds->inBuff, neededInSize); + if (ZSTD_isError(decodedSize)) + return decodedSize; + zds->inPos = 0; /* input is consumed */ + if (!decodedSize && !isSkipFrame) { + zds->stage = zdss_read; + break; + } /* this was just a header */ + zds->outEnd = zds->outStart + decodedSize; + zds->stage = zdss_flush; + /* pass-through */ + } + } + /* fall through */ + + case zdss_flush: { + size_t const toFlushSize = zds->outEnd - zds->outStart; + size_t const flushedSize = ZSTD_limitCopy(op, oend - op, zds->outBuff + zds->outStart, toFlushSize); + op += flushedSize; + zds->outStart += flushedSize; + if (flushedSize == toFlushSize) { /* flush completed */ + zds->stage = zdss_read; + if (zds->outStart + zds->blockSize > zds->outBuffSize) + zds->outStart = zds->outEnd = 0; + break; + } + /* cannot complete flush */ + someMoreWork = 0; + break; + } + default: + return ERROR(GENERIC); /* impossible */ + } + } + + /* result */ + input->pos += (size_t)(ip - istart); + output->pos += (size_t)(op - ostart); + { + size_t nextSrcSizeHint = ZSTD_nextSrcSizeToDecompress(zds->dctx); + if (!nextSrcSizeHint) { /* frame fully decoded */ + if (zds->outEnd == zds->outStart) { /* output fully flushed */ + if (zds->hostageByte) { + if (input->pos >= input->size) { + zds->stage = zdss_read; + return 1; + } /* can't release hostage (not present) */ + input->pos++; /* release hostage */ + } + return 0; + } + if (!zds->hostageByte) { /* output not fully flushed; keep last byte as hostage; will be released when all output is flushed */ + input->pos--; /* note : pos > 0, otherwise, impossible to finish reading last block */ + zds->hostageByte = 1; + } + return 1; + } + nextSrcSizeHint += ZSTD_blockHeaderSize * (ZSTD_nextInputType(zds->dctx) == ZSTDnit_block); /* preload header of next block */ + if (zds->inPos > nextSrcSizeHint) + return ERROR(GENERIC); /* should never happen */ + nextSrcSizeHint -= zds->inPos; /* already loaded*/ + return nextSrcSizeHint; + } +} + +EXPORT_SYMBOL(ZSTD_DCtxWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initDCtx); +EXPORT_SYMBOL(ZSTD_decompressDCtx); +EXPORT_SYMBOL(ZSTD_decompress_usingDict); + +EXPORT_SYMBOL(ZSTD_DDictWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initDDict); +EXPORT_SYMBOL(ZSTD_decompress_usingDDict); + +EXPORT_SYMBOL(ZSTD_DStreamWorkspaceBound); +EXPORT_SYMBOL(ZSTD_initDStream); +EXPORT_SYMBOL(ZSTD_initDStream_usingDDict); +EXPORT_SYMBOL(ZSTD_resetDStream); +EXPORT_SYMBOL(ZSTD_decompressStream); +EXPORT_SYMBOL(ZSTD_DStreamInSize); +EXPORT_SYMBOL(ZSTD_DStreamOutSize); + +EXPORT_SYMBOL(ZSTD_findFrameCompressedSize); +EXPORT_SYMBOL(ZSTD_getFrameContentSize); +EXPORT_SYMBOL(ZSTD_findDecompressedSize); + +EXPORT_SYMBOL(ZSTD_isFrame); +EXPORT_SYMBOL(ZSTD_getDictID_fromDict); +EXPORT_SYMBOL(ZSTD_getDictID_fromDDict); +EXPORT_SYMBOL(ZSTD_getDictID_fromFrame); + +EXPORT_SYMBOL(ZSTD_getFrameParams); +EXPORT_SYMBOL(ZSTD_decompressBegin); +EXPORT_SYMBOL(ZSTD_decompressBegin_usingDict); +EXPORT_SYMBOL(ZSTD_copyDCtx); +EXPORT_SYMBOL(ZSTD_nextSrcSizeToDecompress); +EXPORT_SYMBOL(ZSTD_decompressContinue); +EXPORT_SYMBOL(ZSTD_nextInputType); + +EXPORT_SYMBOL(ZSTD_decompressBlock); +EXPORT_SYMBOL(ZSTD_insertBlock); + +MODULE_LICENSE("Dual BSD/GPL"); +MODULE_DESCRIPTION("Zstd Decompressor"); diff --git a/xen/common/zstd/entropy_common.c b/xen/common/zstd/entropy_common.c new file mode 100644 index 0000000000..2b0a643c32 --- /dev/null +++ b/xen/common/zstd/entropy_common.c @@ -0,0 +1,243 @@ +/* + * Common functions of New Generation Entropy library + * Copyright (C) 2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************* +* Dependencies +***************************************/ +#include "error_private.h" /* ERR_*, ERROR */ +#include "fse.h" +#include "huf.h" +#include "mem.h" + +/*=== Version ===*/ +unsigned FSE_versionNumber(void) { return FSE_VERSION_NUMBER; } + +/*=== Error Management ===*/ +unsigned FSE_isError(size_t code) { return ERR_isError(code); } + +unsigned HUF_isError(size_t code) { return ERR_isError(code); } + +/*-************************************************************** +* FSE NCount encoding-decoding +****************************************************************/ +size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSVPtr, unsigned *tableLogPtr, const void *headerBuffer, size_t hbSize) +{ + const BYTE *const istart = (const BYTE *)headerBuffer; + const BYTE *const iend = istart + hbSize; + const BYTE *ip = istart; + int nbBits; + int remaining; + int threshold; + U32 bitStream; + int bitCount; + unsigned charnum = 0; + int previous0 = 0; + + if (hbSize < 4) + return ERROR(srcSize_wrong); + bitStream = ZSTD_readLE32(ip); + nbBits = (bitStream & 0xF) + FSE_MIN_TABLELOG; /* extract tableLog */ + if (nbBits > FSE_TABLELOG_ABSOLUTE_MAX) + return ERROR(tableLog_tooLarge); + bitStream >>= 4; + bitCount = 4; + *tableLogPtr = nbBits; + remaining = (1 << nbBits) + 1; + threshold = 1 << nbBits; + nbBits++; + + while ((remaining > 1) & (charnum <= *maxSVPtr)) { + if (previous0) { + unsigned n0 = charnum; + while ((bitStream & 0xFFFF) == 0xFFFF) { + n0 += 24; + if (ip < iend - 5) { + ip += 2; + bitStream = ZSTD_readLE32(ip) >> bitCount; + } else { + bitStream >>= 16; + bitCount += 16; + } + } + while ((bitStream & 3) == 3) { + n0 += 3; + bitStream >>= 2; + bitCount += 2; + } + n0 += bitStream & 3; + bitCount += 2; + if (n0 > *maxSVPtr) + return ERROR(maxSymbolValue_tooSmall); + while (charnum < n0) + normalizedCounter[charnum++] = 0; + if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) { + ip += bitCount >> 3; + bitCount &= 7; + bitStream = ZSTD_readLE32(ip) >> bitCount; + } else { + bitStream >>= 2; + } + } + { + int const max = (2 * threshold - 1) - remaining; + int count; + + if ((bitStream & (threshold - 1)) < (U32)max) { + count = bitStream & (threshold - 1); + bitCount += nbBits - 1; + } else { + count = bitStream & (2 * threshold - 1); + if (count >= threshold) + count -= max; + bitCount += nbBits; + } + + count--; /* extra accuracy */ + remaining -= count < 0 ? -count : count; /* -1 means +1 */ + normalizedCounter[charnum++] = (short)count; + previous0 = !count; + while (remaining < threshold) { + nbBits--; + threshold >>= 1; + } + + if ((ip <= iend - 7) || (ip + (bitCount >> 3) <= iend - 4)) { + ip += bitCount >> 3; + bitCount &= 7; + } else { + bitCount -= (int)(8 * (iend - 4 - ip)); + ip = iend - 4; + } + bitStream = ZSTD_readLE32(ip) >> (bitCount & 31); + } + } /* while ((remaining>1) & (charnum<=*maxSVPtr)) */ + if (remaining != 1) + return ERROR(corruption_detected); + if (bitCount > 32) + return ERROR(corruption_detected); + *maxSVPtr = charnum - 1; + + ip += (bitCount + 7) >> 3; + return ip - istart; +} + +/*! HUF_readStats() : + Read compact Huffman tree, saved by HUF_writeCTable(). + `huffWeight` is destination buffer. + `rankStats` is assumed to be a table of at least HUF_TABLELOG_MAX U32. + @return : size read from `src` , or an error Code . + Note : Needed by HUF_readCTable() and HUF_readDTableX?() . +*/ +size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 weightTotal; + const BYTE *ip = (const BYTE *)src; + size_t iSize; + size_t oSize; + + if (!srcSize) + return ERROR(srcSize_wrong); + iSize = ip[0]; + /* memset(huffWeight, 0, hwSize); */ /* is not necessary, even though some analyzer complain ... */ + + if (iSize >= 128) { /* special header */ + oSize = iSize - 127; + iSize = ((oSize + 1) / 2); + if (iSize + 1 > srcSize) + return ERROR(srcSize_wrong); + if (oSize >= hwSize) + return ERROR(corruption_detected); + ip += 1; + { + U32 n; + for (n = 0; n < oSize; n += 2) { + huffWeight[n] = ip[n / 2] >> 4; + huffWeight[n + 1] = ip[n / 2] & 15; + } + } + } else { /* header compressed with FSE (normal case) */ + if (iSize + 1 > srcSize) + return ERROR(srcSize_wrong); + oSize = FSE_decompress_wksp(huffWeight, hwSize - 1, ip + 1, iSize, 6, workspace, workspaceSize); /* max (hwSize-1) values decoded, as last one is implied */ + if (FSE_isError(oSize)) + return oSize; + } + + /* collect weight stats */ + memset(rankStats, 0, (HUF_TABLELOG_MAX + 1) * sizeof(U32)); + weightTotal = 0; + { + U32 n; + for (n = 0; n < oSize; n++) { + if (huffWeight[n] >= HUF_TABLELOG_MAX) + return ERROR(corruption_detected); + rankStats[huffWeight[n]]++; + weightTotal += (1 << huffWeight[n]) >> 1; + } + } + if (weightTotal == 0) + return ERROR(corruption_detected); + + /* get last non-null symbol weight (implied, total must be 2^n) */ + { + U32 const tableLog = BIT_highbit32(weightTotal) + 1; + if (tableLog > HUF_TABLELOG_MAX) + return ERROR(corruption_detected); + *tableLogPtr = tableLog; + /* determine last weight */ + { + U32 const total = 1 << tableLog; + U32 const rest = total - weightTotal; + U32 const verif = 1 << BIT_highbit32(rest); + U32 const lastWeight = BIT_highbit32(rest) + 1; + if (verif != rest) + return ERROR(corruption_detected); /* last value must be a clean power of 2 */ + huffWeight[oSize] = (BYTE)lastWeight; + rankStats[lastWeight]++; + } + } + + /* check tree construction validity */ + if ((rankStats[1] < 2) || (rankStats[1] & 1)) + return ERROR(corruption_detected); /* by construction : at least 2 elts of rank 1, must be even */ + + /* results */ + *nbSymbolsPtr = (U32)(oSize + 1); + return iSize + 1; +} diff --git a/xen/common/zstd/error_private.h b/xen/common/zstd/error_private.h new file mode 100644 index 0000000000..1a60b31f70 --- /dev/null +++ b/xen/common/zstd/error_private.h @@ -0,0 +1,53 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/* Note : this module is expected to remain private, do not expose it */ + +#ifndef ERROR_H_MODULE +#define ERROR_H_MODULE + +/* **************************************** +* Dependencies +******************************************/ +#include /* size_t */ +#include /* enum list */ + +/* **************************************** +* Compiler-specific +******************************************/ +#define ERR_STATIC static __attribute__((unused)) + +/*-**************************************** +* Customization (error_public.h) +******************************************/ +typedef ZSTD_ErrorCode ERR_enum; +#define PREFIX(name) ZSTD_error_##name + +/*-**************************************** +* Error codes handling +******************************************/ +#define ERROR(name) ((size_t)-PREFIX(name)) + +ERR_STATIC unsigned ERR_isError(size_t code) { return (code > ERROR(maxCode)); } + +ERR_STATIC ERR_enum ERR_getErrorCode(size_t code) +{ + if (!ERR_isError(code)) + return (ERR_enum)0; + return (ERR_enum)(0 - code); +} + +#endif /* ERROR_H_MODULE */ diff --git a/xen/common/zstd/fse.h b/xen/common/zstd/fse.h new file mode 100644 index 0000000000..7460ab04b1 --- /dev/null +++ b/xen/common/zstd/fse.h @@ -0,0 +1,575 @@ +/* + * FSE : Finite State Entropy codec + * Public Prototypes declaration + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ +#ifndef FSE_H +#define FSE_H + +/*-***************************************** +* Dependencies +******************************************/ +#include /* size_t, ptrdiff_t */ + +/*-***************************************** +* FSE_PUBLIC_API : control library symbols visibility +******************************************/ +#define FSE_PUBLIC_API + +/*------ Version ------*/ +#define FSE_VERSION_MAJOR 0 +#define FSE_VERSION_MINOR 9 +#define FSE_VERSION_RELEASE 0 + +#define FSE_LIB_VERSION FSE_VERSION_MAJOR.FSE_VERSION_MINOR.FSE_VERSION_RELEASE +#define FSE_QUOTE(str) #str +#define FSE_EXPAND_AND_QUOTE(str) FSE_QUOTE(str) +#define FSE_VERSION_STRING FSE_EXPAND_AND_QUOTE(FSE_LIB_VERSION) + +#define FSE_VERSION_NUMBER (FSE_VERSION_MAJOR * 100 * 100 + FSE_VERSION_MINOR * 100 + FSE_VERSION_RELEASE) +FSE_PUBLIC_API unsigned FSE_versionNumber(void); /**< library version number; to be used when checking dll version */ + +/*-***************************************** +* Tool functions +******************************************/ +FSE_PUBLIC_API size_t FSE_compressBound(size_t size); /* maximum compressed size */ + +/* Error Management */ +FSE_PUBLIC_API unsigned FSE_isError(size_t code); /* tells if a return value is an error code */ + +/*-***************************************** +* FSE detailed API +******************************************/ +/*! +FSE_compress() does the following: +1. count symbol occurrence from source[] into table count[] +2. normalize counters so that sum(count[]) == Power_of_2 (2^tableLog) +3. save normalized counters to memory buffer using writeNCount() +4. build encoding table 'CTable' from normalized counters +5. encode the data stream using encoding table 'CTable' + +FSE_decompress() does the following: +1. read normalized counters with readNCount() +2. build decoding table 'DTable' from normalized counters +3. decode the data stream using decoding table 'DTable' + +The following API allows targeting specific sub-functions for advanced tasks. +For example, it's possible to compress several blocks using the same 'CTable', +or to save and provide normalized distribution using external method. +*/ + +/* *** COMPRESSION *** */ +/*! FSE_optimalTableLog(): + dynamically downsize 'tableLog' when conditions are met. + It saves CPU time, by using smaller tables, while preserving or even improving compression ratio. + @return : recommended tableLog (necessarily <= 'maxTableLog') */ +FSE_PUBLIC_API unsigned FSE_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue); + +/*! FSE_normalizeCount(): + normalize counts so that sum(count[]) == Power_of_2 (2^tableLog) + 'normalizedCounter' is a table of short, of minimum size (maxSymbolValue+1). + @return : tableLog, + or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_normalizeCount(short *normalizedCounter, unsigned tableLog, const unsigned *count, size_t srcSize, unsigned maxSymbolValue); + +/*! FSE_NCountWriteBound(): + Provides the maximum possible size of an FSE normalized table, given 'maxSymbolValue' and 'tableLog'. + Typically useful for allocation purpose. */ +FSE_PUBLIC_API size_t FSE_NCountWriteBound(unsigned maxSymbolValue, unsigned tableLog); + +/*! FSE_writeNCount(): + Compactly save 'normalizedCounter' into 'buffer'. + @return : size of the compressed table, + or an errorCode, which can be tested using FSE_isError(). */ +FSE_PUBLIC_API size_t FSE_writeNCount(void *buffer, size_t bufferSize, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog); + +/*! Constructor and Destructor of FSE_CTable. + Note that FSE_CTable size depends on 'tableLog' and 'maxSymbolValue' */ +typedef unsigned FSE_CTable; /* don't allocate that. It's only meant to be more restrictive than void* */ + +/*! FSE_compress_usingCTable(): + Compress `src` using `ct` into `dst` which must be already allocated. + @return : size of compressed data (<= `dstCapacity`), + or 0 if compressed data could not fit into `dst`, + or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_compress_usingCTable(void *dst, size_t dstCapacity, const void *src, size_t srcSize, const FSE_CTable *ct); + +/*! +Tutorial : +---------- +The first step is to count all symbols. FSE_count() does this job very fast. +Result will be saved into 'count', a table of unsigned int, which must be already allocated, and have 'maxSymbolValuePtr[0]+1' cells. +'src' is a table of bytes of size 'srcSize'. All values within 'src' MUST be <= maxSymbolValuePtr[0] +maxSymbolValuePtr[0] will be updated, with its real value (necessarily <= original value) +FSE_count() will return the number of occurrence of the most frequent symbol. +This can be used to know if there is a single symbol within 'src', and to quickly evaluate its compressibility. +If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()). + +The next step is to normalize the frequencies. +FSE_normalizeCount() will ensure that sum of frequencies is == 2 ^'tableLog'. +It also guarantees a minimum of 1 to any Symbol with frequency >= 1. +You can use 'tableLog'==0 to mean "use default tableLog value". +If you are unsure of which tableLog value to use, you can ask FSE_optimalTableLog(), +which will provide the optimal valid tableLog given sourceSize, maxSymbolValue, and a user-defined maximum (0 means "default"). + +The result of FSE_normalizeCount() will be saved into a table, +called 'normalizedCounter', which is a table of signed short. +'normalizedCounter' must be already allocated, and have at least 'maxSymbolValue+1' cells. +The return value is tableLog if everything proceeded as expected. +It is 0 if there is a single symbol within distribution. +If there is an error (ex: invalid tableLog value), the function will return an ErrorCode (which can be tested using FSE_isError()). + +'normalizedCounter' can be saved in a compact manner to a memory area using FSE_writeNCount(). +'buffer' must be already allocated. +For guaranteed success, buffer size must be at least FSE_headerBound(). +The result of the function is the number of bytes written into 'buffer'. +If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError(); ex : buffer size too small). + +'normalizedCounter' can then be used to create the compression table 'CTable'. +The space required by 'CTable' must be already allocated, using FSE_createCTable(). +You can then use FSE_buildCTable() to fill 'CTable'. +If there is an error, both functions will return an ErrorCode (which can be tested using FSE_isError()). + +'CTable' can then be used to compress 'src', with FSE_compress_usingCTable(). +Similar to FSE_count(), the convention is that 'src' is assumed to be a table of char of size 'srcSize' +The function returns the size of compressed data (without header), necessarily <= `dstCapacity`. +If it returns '0', compressed data could not fit into 'dst'. +If there is an error, the function will return an ErrorCode (which can be tested using FSE_isError()). +*/ + +/* *** DECOMPRESSION *** */ + +/*! FSE_readNCount(): + Read compactly saved 'normalizedCounter' from 'rBuffer'. + @return : size read from 'rBuffer', + or an errorCode, which can be tested using FSE_isError(). + maxSymbolValuePtr[0] and tableLogPtr[0] will also be updated with their respective values */ +FSE_PUBLIC_API size_t FSE_readNCount(short *normalizedCounter, unsigned *maxSymbolValuePtr, unsigned *tableLogPtr, const void *rBuffer, size_t rBuffSize); + +/*! Constructor and Destructor of FSE_DTable. + Note that its size depends on 'tableLog' */ +typedef unsigned FSE_DTable; /* don't allocate that. It's just a way to be more restrictive than void* */ + +/*! FSE_buildDTable(): + Builds 'dt', which must be already allocated, using FSE_createDTable(). + return : 0, or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize); + +/*! FSE_decompress_usingDTable(): + Decompress compressed source `cSrc` of size `cSrcSize` using `dt` + into `dst` which must be already allocated. + @return : size of regenerated data (necessarily <= `dstCapacity`), + or an errorCode, which can be tested using FSE_isError() */ +FSE_PUBLIC_API size_t FSE_decompress_usingDTable(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt); + +/*! +Tutorial : +---------- +(Note : these functions only decompress FSE-compressed blocks. + If block is uncompressed, use memcpy() instead + If block is a single repeated byte, use memset() instead ) + +The first step is to obtain the normalized frequencies of symbols. +This can be performed by FSE_readNCount() if it was saved using FSE_writeNCount(). +'normalizedCounter' must be already allocated, and have at least 'maxSymbolValuePtr[0]+1' cells of signed short. +In practice, that means it's necessary to know 'maxSymbolValue' beforehand, +or size the table to handle worst case situations (typically 256). +FSE_readNCount() will provide 'tableLog' and 'maxSymbolValue'. +The result of FSE_readNCount() is the number of bytes read from 'rBuffer'. +Note that 'rBufferSize' must be at least 4 bytes, even if useful information is less than that. +If there is an error, the function will return an error code, which can be tested using FSE_isError(). + +The next step is to build the decompression tables 'FSE_DTable' from 'normalizedCounter'. +This is performed by the function FSE_buildDTable(). +The space required by 'FSE_DTable' must be already allocated using FSE_createDTable(). +If there is an error, the function will return an error code, which can be tested using FSE_isError(). + +`FSE_DTable` can then be used to decompress `cSrc`, with FSE_decompress_usingDTable(). +`cSrcSize` must be strictly correct, otherwise decompression will fail. +FSE_decompress_usingDTable() result will tell how many bytes were regenerated (<=`dstCapacity`). +If there is an error, the function will return an error code, which can be tested using FSE_isError(). (ex: dst buffer too small) +*/ + +/* *** Dependency *** */ +#include "bitstream.h" + +/* ***************************************** +* Static allocation +*******************************************/ +/* FSE buffer bounds */ +#define FSE_NCOUNTBOUND 512 +#define FSE_BLOCKBOUND(size) (size + (size >> 7)) +#define FSE_COMPRESSBOUND(size) (FSE_NCOUNTBOUND + FSE_BLOCKBOUND(size)) /* Macro version, useful for static allocation */ + +/* It is possible to statically allocate FSE CTable/DTable as a table of FSE_CTable/FSE_DTable using below macros */ +#define FSE_CTABLE_SIZE_U32(maxTableLog, maxSymbolValue) (1 + (1 << (maxTableLog - 1)) + ((maxSymbolValue + 1) * 2)) +#define FSE_DTABLE_SIZE_U32(maxTableLog) (1 + (1 << maxTableLog)) + +/* ***************************************** +* FSE advanced API +*******************************************/ +/* FSE_count_wksp() : + * Same as FSE_count(), but using an externally provided scratch buffer. + * `workSpace` size must be table of >= `1024` unsigned + */ +size_t FSE_count_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *source, size_t sourceSize, unsigned *workSpace); + +/* FSE_countFast_wksp() : + * Same as FSE_countFast(), but using an externally provided scratch buffer. + * `workSpace` must be a table of minimum `1024` unsigned + */ +size_t FSE_countFast_wksp(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize, unsigned *workSpace); + +/*! FSE_count_simple + * Same as FSE_countFast(), but does not use any additional memory (not even on stack). + * This function is unsafe, and will segfault if any value within `src` is `> *maxSymbolValuePtr` (presuming it's also the size of `count`). +*/ +size_t FSE_count_simple(unsigned *count, unsigned *maxSymbolValuePtr, const void *src, size_t srcSize); + +unsigned FSE_optimalTableLog_internal(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue, unsigned minus); +/**< same as FSE_optimalTableLog(), which used `minus==2` */ + +size_t FSE_buildCTable_raw(FSE_CTable *ct, unsigned nbBits); +/**< build a fake FSE_CTable, designed for a flat distribution, where each symbol uses nbBits */ + +size_t FSE_buildCTable_rle(FSE_CTable *ct, unsigned char symbolValue); +/**< build a fake FSE_CTable, designed to compress always the same symbolValue */ + +/* FSE_buildCTable_wksp() : + * Same as FSE_buildCTable(), but using an externally allocated scratch buffer (`workSpace`). + * `wkspSize` must be >= `(1<= BIT_DStream_completed + +When it's done, verify decompression is fully completed, by checking both DStream and the relevant states. +Checking if DStream has reached its end is performed by : + BIT_endOfDStream(&DStream); +Check also the states. There might be some symbols left there, if some high probability ones (>50%) are possible. + FSE_endOfDState(&DState); +*/ + +/* ***************************************** +* FSE unsafe API +*******************************************/ +static unsigned char FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD); +/* faster, but works only if nbBits is always >= 1 (otherwise, result will be corrupted) */ + +/* ***************************************** +* Implementation of inlined functions +*******************************************/ +typedef struct { + int deltaFindState; + U32 deltaNbBits; +} FSE_symbolCompressionTransform; /* total 8 bytes */ + +ZSTD_STATIC void FSE_initCState(FSE_CState_t *statePtr, const FSE_CTable *ct) +{ + const void *ptr = ct; + const U16 *u16ptr = (const U16 *)ptr; + const U32 tableLog = ZSTD_read16(ptr); + statePtr->value = (ptrdiff_t)1 << tableLog; + statePtr->stateTable = u16ptr + 2; + statePtr->symbolTT = ((const U32 *)ct + 1 + (tableLog ? (1 << (tableLog - 1)) : 1)); + statePtr->stateLog = tableLog; +} + +/*! FSE_initCState2() : +* Same as FSE_initCState(), but the first symbol to include (which will be the last to be read) +* uses the smallest state value possible, saving the cost of this symbol */ +ZSTD_STATIC void FSE_initCState2(FSE_CState_t *statePtr, const FSE_CTable *ct, U32 symbol) +{ + FSE_initCState(statePtr, ct); + { + const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol]; + const U16 *stateTable = (const U16 *)(statePtr->stateTable); + U32 nbBitsOut = (U32)((symbolTT.deltaNbBits + (1 << 15)) >> 16); + statePtr->value = (nbBitsOut << 16) - symbolTT.deltaNbBits; + statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState]; + } +} + +ZSTD_STATIC void FSE_encodeSymbol(BIT_CStream_t *bitC, FSE_CState_t *statePtr, U32 symbol) +{ + const FSE_symbolCompressionTransform symbolTT = ((const FSE_symbolCompressionTransform *)(statePtr->symbolTT))[symbol]; + const U16 *const stateTable = (const U16 *)(statePtr->stateTable); + U32 nbBitsOut = (U32)((statePtr->value + symbolTT.deltaNbBits) >> 16); + BIT_addBits(bitC, statePtr->value, nbBitsOut); + statePtr->value = stateTable[(statePtr->value >> nbBitsOut) + symbolTT.deltaFindState]; +} + +ZSTD_STATIC void FSE_flushCState(BIT_CStream_t *bitC, const FSE_CState_t *statePtr) +{ + BIT_addBits(bitC, statePtr->value, statePtr->stateLog); + BIT_flushBits(bitC); +} + +/* ====== Decompression ====== */ + +typedef struct { + U16 tableLog; + U16 fastMode; +} FSE_DTableHeader; /* sizeof U32 */ + +typedef struct { + unsigned short newState; + unsigned char symbol; + unsigned char nbBits; +} FSE_decode_t; /* size == U32 */ + +ZSTD_STATIC void FSE_initDState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD, const FSE_DTable *dt) +{ + const void *ptr = dt; + const FSE_DTableHeader *const DTableH = (const FSE_DTableHeader *)ptr; + DStatePtr->state = BIT_readBits(bitD, DTableH->tableLog); + BIT_reloadDStream(bitD); + DStatePtr->table = dt + 1; +} + +ZSTD_STATIC BYTE FSE_peekSymbol(const FSE_DState_t *DStatePtr) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + return DInfo.symbol; +} + +ZSTD_STATIC void FSE_updateState(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + U32 const nbBits = DInfo.nbBits; + size_t const lowBits = BIT_readBits(bitD, nbBits); + DStatePtr->state = DInfo.newState + lowBits; +} + +ZSTD_STATIC BYTE FSE_decodeSymbol(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + U32 const nbBits = DInfo.nbBits; + BYTE const symbol = DInfo.symbol; + size_t const lowBits = BIT_readBits(bitD, nbBits); + + DStatePtr->state = DInfo.newState + lowBits; + return symbol; +} + +/*! FSE_decodeSymbolFast() : + unsafe, only works if no symbol has a probability > 50% */ +ZSTD_STATIC BYTE FSE_decodeSymbolFast(FSE_DState_t *DStatePtr, BIT_DStream_t *bitD) +{ + FSE_decode_t const DInfo = ((const FSE_decode_t *)(DStatePtr->table))[DStatePtr->state]; + U32 const nbBits = DInfo.nbBits; + BYTE const symbol = DInfo.symbol; + size_t const lowBits = BIT_readBitsFast(bitD, nbBits); + + DStatePtr->state = DInfo.newState + lowBits; + return symbol; +} + +ZSTD_STATIC unsigned FSE_endOfDState(const FSE_DState_t *DStatePtr) { return DStatePtr->state == 0; } + +/* ************************************************************** +* Tuning parameters +****************************************************************/ +/*!MEMORY_USAGE : +* Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.) +* Increasing memory usage improves compression ratio +* Reduced memory usage can improve speed, due to cache effect +* Recommended max value is 14, for 16KB, which nicely fits into Intel x86 L1 cache */ +#ifndef FSE_MAX_MEMORY_USAGE +#define FSE_MAX_MEMORY_USAGE 14 +#endif +#ifndef FSE_DEFAULT_MEMORY_USAGE +#define FSE_DEFAULT_MEMORY_USAGE 13 +#endif + +/*!FSE_MAX_SYMBOL_VALUE : +* Maximum symbol value authorized. +* Required for proper stack allocation */ +#ifndef FSE_MAX_SYMBOL_VALUE +#define FSE_MAX_SYMBOL_VALUE 255 +#endif + +/* ************************************************************** +* template functions type & suffix +****************************************************************/ +#define FSE_FUNCTION_TYPE BYTE +#define FSE_FUNCTION_EXTENSION +#define FSE_DECODE_TYPE FSE_decode_t + +/* *************************************************************** +* Constants +*****************************************************************/ +#define FSE_MAX_TABLELOG (FSE_MAX_MEMORY_USAGE - 2) +#define FSE_MAX_TABLESIZE (1U << FSE_MAX_TABLELOG) +#define FSE_MAXTABLESIZE_MASK (FSE_MAX_TABLESIZE - 1) +#define FSE_DEFAULT_TABLELOG (FSE_DEFAULT_MEMORY_USAGE - 2) +#define FSE_MIN_TABLELOG 5 + +#define FSE_TABLELOG_ABSOLUTE_MAX 15 +#if FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX +#error "FSE_MAX_TABLELOG > FSE_TABLELOG_ABSOLUTE_MAX is not supported" +#endif + +#define FSE_TABLESTEP(tableSize) ((tableSize >> 1) + (tableSize >> 3) + 3) + +#endif /* FSE_H */ diff --git a/xen/common/zstd/fse_decompress.c b/xen/common/zstd/fse_decompress.c new file mode 100644 index 0000000000..0b353530fb --- /dev/null +++ b/xen/common/zstd/fse_decompress.c @@ -0,0 +1,325 @@ +/* + * FSE : Finite State Entropy decoder + * Copyright (C) 2013-2015, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#define FORCE_INLINE static __always_inline + +/* ************************************************************** +* Includes +****************************************************************/ +#include "bitstream.h" +#include "fse.h" +#include "zstd_internal.h" +#include +#include +#include /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define FSE_isError ERR_isError +#define FSE_STATIC_ASSERT(c) \ + { \ + enum { FSE_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ + +/* ************************************************************** +* Templates +****************************************************************/ +/* + designed to be included + for type-specific functions (template emulation in C) + Objective is to write these functions only once, for improved maintenance +*/ + +/* safety checks */ +#ifndef FSE_FUNCTION_EXTENSION +#error "FSE_FUNCTION_EXTENSION must be defined" +#endif +#ifndef FSE_FUNCTION_TYPE +#error "FSE_FUNCTION_TYPE must be defined" +#endif + +/* Function names */ +#define FSE_CAT(X, Y) X##Y +#define FSE_FUNCTION_NAME(X, Y) FSE_CAT(X, Y) +#define FSE_TYPE_NAME(X, Y) FSE_CAT(X, Y) + +/* Function templates */ + +size_t FSE_buildDTable_wksp(FSE_DTable *dt, const short *normalizedCounter, unsigned maxSymbolValue, unsigned tableLog, void *workspace, size_t workspaceSize) +{ + void *const tdPtr = dt + 1; /* because *dt is unsigned, 32-bits aligned on 32-bits */ + FSE_DECODE_TYPE *const tableDecode = (FSE_DECODE_TYPE *)(tdPtr); + U16 *symbolNext = (U16 *)workspace; + + U32 const maxSV1 = maxSymbolValue + 1; + U32 const tableSize = 1 << tableLog; + U32 highThreshold = tableSize - 1; + + /* Sanity Checks */ + if (workspaceSize < sizeof(U16) * (FSE_MAX_SYMBOL_VALUE + 1)) + return ERROR(tableLog_tooLarge); + if (maxSymbolValue > FSE_MAX_SYMBOL_VALUE) + return ERROR(maxSymbolValue_tooLarge); + if (tableLog > FSE_MAX_TABLELOG) + return ERROR(tableLog_tooLarge); + + /* Init, lay down lowprob symbols */ + { + FSE_DTableHeader DTableH; + DTableH.tableLog = (U16)tableLog; + DTableH.fastMode = 1; + { + S16 const largeLimit = (S16)(1 << (tableLog - 1)); + U32 s; + for (s = 0; s < maxSV1; s++) { + if (normalizedCounter[s] == -1) { + tableDecode[highThreshold--].symbol = (FSE_FUNCTION_TYPE)s; + symbolNext[s] = 1; + } else { + if (normalizedCounter[s] >= largeLimit) + DTableH.fastMode = 0; + symbolNext[s] = normalizedCounter[s]; + } + } + } + memcpy(dt, &DTableH, sizeof(DTableH)); + } + + /* Spread symbols */ + { + U32 const tableMask = tableSize - 1; + U32 const step = FSE_TABLESTEP(tableSize); + U32 s, position = 0; + for (s = 0; s < maxSV1; s++) { + int i; + for (i = 0; i < normalizedCounter[s]; i++) { + tableDecode[position].symbol = (FSE_FUNCTION_TYPE)s; + position = (position + step) & tableMask; + while (position > highThreshold) + position = (position + step) & tableMask; /* lowprob area */ + } + } + if (position != 0) + return ERROR(GENERIC); /* position must reach all cells once, otherwise normalizedCounter is incorrect */ + } + + /* Build Decoding table */ + { + U32 u; + for (u = 0; u < tableSize; u++) { + FSE_FUNCTION_TYPE const symbol = (FSE_FUNCTION_TYPE)(tableDecode[u].symbol); + U16 nextState = symbolNext[symbol]++; + tableDecode[u].nbBits = (BYTE)(tableLog - BIT_highbit32((U32)nextState)); + tableDecode[u].newState = (U16)((nextState << tableDecode[u].nbBits) - tableSize); + } + } + + return 0; +} + +/*-******************************************************* +* Decompression (Byte symbols) +*********************************************************/ +size_t FSE_buildDTable_rle(FSE_DTable *dt, BYTE symbolValue) +{ + void *ptr = dt; + FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr; + void *dPtr = dt + 1; + FSE_decode_t *const cell = (FSE_decode_t *)dPtr; + + DTableH->tableLog = 0; + DTableH->fastMode = 0; + + cell->newState = 0; + cell->symbol = symbolValue; + cell->nbBits = 0; + + return 0; +} + +size_t FSE_buildDTable_raw(FSE_DTable *dt, unsigned nbBits) +{ + void *ptr = dt; + FSE_DTableHeader *const DTableH = (FSE_DTableHeader *)ptr; + void *dPtr = dt + 1; + FSE_decode_t *const dinfo = (FSE_decode_t *)dPtr; + const unsigned tableSize = 1 << nbBits; + const unsigned tableMask = tableSize - 1; + const unsigned maxSV1 = tableMask + 1; + unsigned s; + + /* Sanity checks */ + if (nbBits < 1) + return ERROR(GENERIC); /* min size */ + + /* Build Decoding Table */ + DTableH->tableLog = (U16)nbBits; + DTableH->fastMode = 1; + for (s = 0; s < maxSV1; s++) { + dinfo[s].newState = 0; + dinfo[s].symbol = (BYTE)s; + dinfo[s].nbBits = (BYTE)nbBits; + } + + return 0; +} + +FORCE_INLINE size_t FSE_decompress_usingDTable_generic(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt, + const unsigned fast) +{ + BYTE *const ostart = (BYTE *)dst; + BYTE *op = ostart; + BYTE *const omax = op + maxDstSize; + BYTE *const olimit = omax - 3; + + BIT_DStream_t bitD; + FSE_DState_t state1; + FSE_DState_t state2; + + /* Init */ + CHECK_F(BIT_initDStream(&bitD, cSrc, cSrcSize)); + + FSE_initDState(&state1, &bitD, dt); + FSE_initDState(&state2, &bitD, dt); + +#define FSE_GETSYMBOL(statePtr) fast ? FSE_decodeSymbolFast(statePtr, &bitD) : FSE_decodeSymbol(statePtr, &bitD) + + /* 4 symbols per loop */ + for (; (BIT_reloadDStream(&bitD) == BIT_DStream_unfinished) & (op < olimit); op += 4) { + op[0] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */ + BIT_reloadDStream(&bitD); + + op[1] = FSE_GETSYMBOL(&state2); + + if (FSE_MAX_TABLELOG * 4 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */ + { + if (BIT_reloadDStream(&bitD) > BIT_DStream_unfinished) { + op += 2; + break; + } + } + + op[2] = FSE_GETSYMBOL(&state1); + + if (FSE_MAX_TABLELOG * 2 + 7 > sizeof(bitD.bitContainer) * 8) /* This test must be static */ + BIT_reloadDStream(&bitD); + + op[3] = FSE_GETSYMBOL(&state2); + } + + /* tail */ + /* note : BIT_reloadDStream(&bitD) >= FSE_DStream_partiallyFilled; Ends at exactly BIT_DStream_completed */ + while (1) { + if (op > (omax - 2)) + return ERROR(dstSize_tooSmall); + *op++ = FSE_GETSYMBOL(&state1); + if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) { + *op++ = FSE_GETSYMBOL(&state2); + break; + } + + if (op > (omax - 2)) + return ERROR(dstSize_tooSmall); + *op++ = FSE_GETSYMBOL(&state2); + if (BIT_reloadDStream(&bitD) == BIT_DStream_overflow) { + *op++ = FSE_GETSYMBOL(&state1); + break; + } + } + + return op - ostart; +} + +size_t FSE_decompress_usingDTable(void *dst, size_t originalSize, const void *cSrc, size_t cSrcSize, const FSE_DTable *dt) +{ + const void *ptr = dt; + const FSE_DTableHeader *DTableH = (const FSE_DTableHeader *)ptr; + const U32 fastMode = DTableH->fastMode; + + /* select fast mode (static) */ + if (fastMode) + return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 1); + return FSE_decompress_usingDTable_generic(dst, originalSize, cSrc, cSrcSize, dt, 0); +} + +size_t FSE_decompress_wksp(void *dst, size_t dstCapacity, const void *cSrc, size_t cSrcSize, unsigned maxLog, void *workspace, size_t workspaceSize) +{ + const BYTE *const istart = (const BYTE *)cSrc; + const BYTE *ip = istart; + unsigned tableLog; + unsigned maxSymbolValue = FSE_MAX_SYMBOL_VALUE; + size_t NCountLength; + + FSE_DTable *dt; + short *counting; + size_t spaceUsed32 = 0; + + FSE_STATIC_ASSERT(sizeof(FSE_DTable) == sizeof(U32)); + + dt = (FSE_DTable *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += FSE_DTABLE_SIZE_U32(maxLog); + counting = (short *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(short) * (FSE_MAX_SYMBOL_VALUE + 1), sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + /* normal FSE decoding mode */ + NCountLength = FSE_readNCount(counting, &maxSymbolValue, &tableLog, istart, cSrcSize); + if (FSE_isError(NCountLength)) + return NCountLength; + // if (NCountLength >= cSrcSize) return ERROR(srcSize_wrong); /* too small input size; supposed to be already checked in NCountLength, only remaining + // case : NCountLength==cSrcSize */ + if (tableLog > maxLog) + return ERROR(tableLog_tooLarge); + ip += NCountLength; + cSrcSize -= NCountLength; + + CHECK_F(FSE_buildDTable_wksp(dt, counting, maxSymbolValue, tableLog, workspace, workspaceSize)); + + return FSE_decompress_usingDTable(dst, dstCapacity, ip, cSrcSize, dt); /* always return, even if it is an error code */ +} diff --git a/xen/common/zstd/huf.h b/xen/common/zstd/huf.h new file mode 100644 index 0000000000..2143da28d9 --- /dev/null +++ b/xen/common/zstd/huf.h @@ -0,0 +1,212 @@ +/* + * Huffman coder, part of New Generation Entropy library + * header file + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ +#ifndef HUF_H_298734234 +#define HUF_H_298734234 + +/* *** Dependencies *** */ +#include /* size_t */ + +/* *** Tool functions *** */ +#define HUF_BLOCKSIZE_MAX (128 * 1024) /**< maximum input size for a single block compressed with HUF_compress */ +size_t HUF_compressBound(size_t size); /**< maximum compressed size (worst case) */ + +/* Error Management */ +unsigned HUF_isError(size_t code); /**< tells if a return value is an error code */ + +/* *** Advanced function *** */ + +/** HUF_compress4X_wksp() : +* Same as HUF_compress2(), but uses externally allocated `workSpace`, which must be a table of >= 1024 unsigned */ +size_t HUF_compress4X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ + +/* *** Dependencies *** */ +#include "mem.h" /* U32 */ + +/* *** Constants *** */ +#define HUF_TABLELOG_MAX 12 /* max configured tableLog (for static allocation); can be modified up to HUF_ABSOLUTEMAX_TABLELOG */ +#define HUF_TABLELOG_DEFAULT 11 /* tableLog by default, when not specified */ +#define HUF_SYMBOLVALUE_MAX 255 + +#define HUF_TABLELOG_ABSOLUTEMAX 15 /* absolute limit of HUF_MAX_TABLELOG. Beyond that value, code does not work */ +#if (HUF_TABLELOG_MAX > HUF_TABLELOG_ABSOLUTEMAX) +#error "HUF_TABLELOG_MAX is too large !" +#endif + +/* **************************************** +* Static allocation +******************************************/ +/* HUF buffer bounds */ +#define HUF_CTABLEBOUND 129 +#define HUF_BLOCKBOUND(size) (size + (size >> 8) + 8) /* only true if incompressible pre-filtered with fast heuristic */ +#define HUF_COMPRESSBOUND(size) (HUF_CTABLEBOUND + HUF_BLOCKBOUND(size)) /* Macro version, useful for static allocation */ + +/* static allocation of HUF's Compression Table */ +#define HUF_CREATE_STATIC_CTABLE(name, maxSymbolValue) \ + U32 name##hb[maxSymbolValue + 1]; \ + void *name##hv = &(name##hb); \ + HUF_CElt *name = (HUF_CElt *)(name##hv) /* no final ; */ + +/* static allocation of HUF's DTable */ +typedef U32 HUF_DTable; +#define HUF_DTABLE_SIZE(maxTableLog) (1 + (1 << (maxTableLog))) +#define HUF_CREATE_STATIC_DTABLEX2(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE((maxTableLog)-1)] = {((U32)((maxTableLog)-1) * 0x01000001)} +#define HUF_CREATE_STATIC_DTABLEX4(DTable, maxTableLog) HUF_DTable DTable[HUF_DTABLE_SIZE(maxTableLog)] = {((U32)(maxTableLog)*0x01000001)} + +/* The workspace must have alignment at least 4 and be at least this large */ +#define HUF_COMPRESS_WORKSPACE_SIZE (6 << 10) +#define HUF_COMPRESS_WORKSPACE_SIZE_U32 (HUF_COMPRESS_WORKSPACE_SIZE / sizeof(U32)) + +/* The workspace must have alignment at least 4 and be at least this large */ +#define HUF_DECOMPRESS_WORKSPACE_SIZE (3 << 10) +#define HUF_DECOMPRESS_WORKSPACE_SIZE_U32 (HUF_DECOMPRESS_WORKSPACE_SIZE / sizeof(U32)) + +/* **************************************** +* Advanced decompression functions +******************************************/ +size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); /**< decodes RLE and uncompressed */ +size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< considers RLE and uncompressed as errors */ +size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< single-symbol decoder */ +size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< double-symbols decoder */ + +/* **************************************** +* HUF detailed API +******************************************/ +/*! +HUF_compress() does the following: +1. count symbol occurrence from source[] into table count[] using FSE_count() +2. (optional) refine tableLog using HUF_optimalTableLog() +3. build Huffman table from count using HUF_buildCTable() +4. save Huffman table to memory buffer using HUF_writeCTable_wksp() +5. encode the data stream using HUF_compress4X_usingCTable() + +The following API allows targeting specific sub-functions for advanced tasks. +For example, it's possible to compress several blocks using the same 'CTable', +or to save and regenerate 'CTable' using external methods. +*/ +/* FSE_count() : find it within "fse.h" */ +unsigned HUF_optimalTableLog(unsigned maxTableLog, size_t srcSize, unsigned maxSymbolValue); +typedef struct HUF_CElt_s HUF_CElt; /* incomplete type */ +size_t HUF_writeCTable_wksp(void *dst, size_t maxDstSize, const HUF_CElt *CTable, unsigned maxSymbolValue, unsigned huffLog, void *workspace, size_t workspaceSize); +size_t HUF_compress4X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable); + +typedef enum { + HUF_repeat_none, /**< Cannot use the previous table */ + HUF_repeat_check, /**< Can use the previous table but it must be checked. Note : The previous table must have been constructed by HUF_compress{1, + 4}X_repeat */ + HUF_repeat_valid /**< Can use the previous table and it is asumed to be valid */ +} HUF_repeat; +/** HUF_compress4X_repeat() : +* Same as HUF_compress4X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none. +* If it uses hufTable it does not modify hufTable or repeat. +* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used. +* If preferRepeat then the old table will always be used if valid. */ +size_t HUF_compress4X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, + int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ + +/** HUF_buildCTable_wksp() : + * Same as HUF_buildCTable(), but using externally allocated scratch buffer. + * `workSpace` must be aligned on 4-bytes boundaries, and be at least as large as a table of 1024 unsigned. + */ +size_t HUF_buildCTable_wksp(HUF_CElt *tree, const U32 *count, U32 maxSymbolValue, U32 maxNbBits, void *workSpace, size_t wkspSize); + +/*! HUF_readStats() : + Read compact Huffman tree, saved by HUF_writeCTable(). + `huffWeight` is destination buffer. + @return : size read from `src` , or an error Code . + Note : Needed by HUF_readCTable() and HUF_readDTableXn() . */ +size_t HUF_readStats_wksp(BYTE *huffWeight, size_t hwSize, U32 *rankStats, U32 *nbSymbolsPtr, U32 *tableLogPtr, const void *src, size_t srcSize, + void *workspace, size_t workspaceSize); + +/** HUF_readCTable() : +* Loading a CTable saved with HUF_writeCTable() */ +size_t HUF_readCTable_wksp(HUF_CElt *CTable, unsigned maxSymbolValue, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); + +/* +HUF_decompress() does the following: +1. select the decompression algorithm (X2, X4) based on pre-computed heuristics +2. build Huffman table from save, using HUF_readDTableXn() +3. decode 1 or 4 segments in parallel using HUF_decompressSXn_usingDTable +*/ + +/** HUF_selectDecoder() : +* Tells which decoder is likely to decode faster, +* based on a set of pre-determined metrics. +* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 . +* Assumption : 0 < cSrcSize < dstSize <= 128 KB */ +U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize); + +size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); +size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize); + +size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); +size_t HUF_decompress4X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); +size_t HUF_decompress4X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); + +/* single stream variants */ + +size_t HUF_compress1X_wksp(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ +size_t HUF_compress1X_usingCTable(void *dst, size_t dstSize, const void *src, size_t srcSize, const HUF_CElt *CTable); +/** HUF_compress1X_repeat() : +* Same as HUF_compress1X_wksp(), but considers using hufTable if *repeat != HUF_repeat_none. +* If it uses hufTable it does not modify hufTable or repeat. +* If it doesn't, it sets *repeat = HUF_repeat_none, and it sets hufTable to the table used. +* If preferRepeat then the old table will always be used if valid. */ +size_t HUF_compress1X_repeat(void *dst, size_t dstSize, const void *src, size_t srcSize, unsigned maxSymbolValue, unsigned tableLog, void *workSpace, + size_t wkspSize, HUF_CElt *hufTable, HUF_repeat *repeat, + int preferRepeat); /**< `workSpace` must be a table of at least HUF_COMPRESS_WORKSPACE_SIZE_U32 unsigned */ + +size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize); +size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< single-symbol decoder */ +size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, + size_t workspaceSize); /**< double-symbols decoder */ + +size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, + const HUF_DTable *DTable); /**< automatic selection of sing or double symbol decoder, based on DTable */ +size_t HUF_decompress1X2_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); +size_t HUF_decompress1X4_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable); + +#endif /* HUF_H_298734234 */ diff --git a/xen/common/zstd/huf_decompress.c b/xen/common/zstd/huf_decompress.c new file mode 100644 index 0000000000..6526482047 --- /dev/null +++ b/xen/common/zstd/huf_decompress.c @@ -0,0 +1,960 @@ +/* + * Huffman decoder, part of New Generation Entropy library + * Copyright (C) 2013-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at : + * - Source repository : https://github.com/Cyan4973/FiniteStateEntropy + */ + +/* ************************************************************** +* Compiler specifics +****************************************************************/ +#define FORCE_INLINE static __always_inline + +/* ************************************************************** +* Dependencies +****************************************************************/ +#include "bitstream.h" /* BIT_* */ +#include "fse.h" /* header compression */ +#include "huf.h" +#include +#include +#include /* memcpy, memset */ + +/* ************************************************************** +* Error Management +****************************************************************/ +#define HUF_STATIC_ASSERT(c) \ + { \ + enum { HUF_static_assert = 1 / (int)(!!(c)) }; \ + } /* use only *after* variable declarations */ + +/*-***************************/ +/* generic DTableDesc */ +/*-***************************/ + +typedef struct { + BYTE maxTableLog; + BYTE tableType; + BYTE tableLog; + BYTE reserved; +} DTableDesc; + +static DTableDesc HUF_getDTableDesc(const HUF_DTable *table) +{ + DTableDesc dtd; + memcpy(&dtd, table, sizeof(dtd)); + return dtd; +} + +/*-***************************/ +/* single-symbol decoding */ +/*-***************************/ + +typedef struct { + BYTE byte; + BYTE nbBits; +} HUF_DEltX2; /* single-symbol decoding */ + +size_t HUF_readDTableX2_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 tableLog = 0; + U32 nbSymbols = 0; + size_t iSize; + void *const dtPtr = DTable + 1; + HUF_DEltX2 *const dt = (HUF_DEltX2 *)dtPtr; + + U32 *rankVal; + BYTE *huffWeight; + size_t spaceUsed32 = 0; + + rankVal = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_ABSOLUTEMAX + 1; + huffWeight = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + HUF_STATIC_ASSERT(sizeof(DTableDesc) == sizeof(HUF_DTable)); + /* memset(huffWeight, 0, sizeof(huffWeight)); */ /* is not necessary, even though some analyzer complain ... */ + + iSize = HUF_readStats_wksp(huffWeight, HUF_SYMBOLVALUE_MAX + 1, rankVal, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (HUF_isError(iSize)) + return iSize; + + /* Table header */ + { + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (tableLog > (U32)(dtd.maxTableLog + 1)) + return ERROR(tableLog_tooLarge); /* DTable too small, Huffman tree cannot fit in */ + dtd.tableType = 0; + dtd.tableLog = (BYTE)tableLog; + memcpy(DTable, &dtd, sizeof(dtd)); + } + + /* Calculate starting value for each rank */ + { + U32 n, nextRankStart = 0; + for (n = 1; n < tableLog + 1; n++) { + U32 const curr = nextRankStart; + nextRankStart += (rankVal[n] << (n - 1)); + rankVal[n] = curr; + } + } + + /* fill DTable */ + { + U32 n; + for (n = 0; n < nbSymbols; n++) { + U32 const w = huffWeight[n]; + U32 const length = (1 << w) >> 1; + U32 u; + HUF_DEltX2 D; + D.byte = (BYTE)n; + D.nbBits = (BYTE)(tableLog + 1 - w); + for (u = rankVal[w]; u < rankVal[w] + length; u++) + dt[u] = D; + rankVal[w] += length; + } + } + + return iSize; +} + +static BYTE HUF_decodeSymbolX2(BIT_DStream_t *Dstream, const HUF_DEltX2 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(Dstream, dtLog); /* note : dtLog >= 1 */ + BYTE const c = dt[val].byte; + BIT_skipBits(Dstream, dt[val].nbBits); + return c; +} + +#define HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) *ptr++ = HUF_decodeSymbolX2(DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX2_1(ptr, DStreamPtr) \ + if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \ + HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) + +#define HUF_DECODE_SYMBOLX2_2(ptr, DStreamPtr) \ + if (ZSTD_64bits()) \ + HUF_DECODE_SYMBOLX2_0(ptr, DStreamPtr) + +FORCE_INLINE size_t HUF_decodeStreamX2(BYTE *p, BIT_DStream_t *const bitDPtr, BYTE *const pEnd, const HUF_DEltX2 *const dt, const U32 dtLog) +{ + BYTE *const pStart = p; + + /* up to 4 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p <= pEnd - 4)) { + HUF_DECODE_SYMBOLX2_2(p, bitDPtr); + HUF_DECODE_SYMBOLX2_1(p, bitDPtr); + HUF_DECODE_SYMBOLX2_2(p, bitDPtr); + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + } + + /* closer to the end */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) && (p < pEnd)) + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + + /* no more data to retrieve from bitstream, hence no need to reload */ + while (p < pEnd) + HUF_DECODE_SYMBOLX2_0(p, bitDPtr); + + return pEnd - pStart; +} + +static size_t HUF_decompress1X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + BYTE *op = (BYTE *)dst; + BYTE *const oend = op + dstSize; + const void *dtPtr = DTable + 1; + const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr; + BIT_DStream_t bitD; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + { + size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize); + if (HUF_isError(errorCode)) + return errorCode; + } + + HUF_decodeStreamX2(op, &bitD, oend, dt, dtLog); + + /* check */ + if (!BIT_endOfDStream(&bitD)) + return ERROR(corruption_detected); + + return dstSize; +} + +size_t HUF_decompress1X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 0) + return ERROR(GENERIC); + return HUF_decompress1X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress1X2_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX2_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress1X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx); +} + +static size_t HUF_decompress4X2_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + /* Check */ + if (cSrcSize < 10) + return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */ + + { + const BYTE *const istart = (const BYTE *)cSrc; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; + const HUF_DEltX2 *const dt = (const HUF_DEltX2 *)dtPtr; + + /* Init */ + BIT_DStream_t bitD1; + BIT_DStream_t bitD2; + BIT_DStream_t bitD3; + BIT_DStream_t bitD4; + size_t const length1 = ZSTD_readLE16(istart); + size_t const length2 = ZSTD_readLE16(istart + 2); + size_t const length3 = ZSTD_readLE16(istart + 4); + size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6); + const BYTE *const istart1 = istart + 6; /* jumpTable */ + const BYTE *const istart2 = istart1 + length1; + const BYTE *const istart3 = istart2 + length2; + const BYTE *const istart4 = istart3 + length3; + const size_t segmentSize = (dstSize + 3) / 4; + BYTE *const opStart2 = ostart + segmentSize; + BYTE *const opStart3 = opStart2 + segmentSize; + BYTE *const opStart4 = opStart3 + segmentSize; + BYTE *op1 = ostart; + BYTE *op2 = opStart2; + BYTE *op3 = opStart3; + BYTE *op4 = opStart4; + U32 endSignal; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + if (length4 > cSrcSize) + return ERROR(corruption_detected); /* overflow */ + { + size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* 16-32 symbols per loop (4-8 symbols per stream) */ + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + for (; (endSignal == BIT_DStream_unfinished) && (op4 < (oend - 7));) { + HUF_DECODE_SYMBOLX2_2(op1, &bitD1); + HUF_DECODE_SYMBOLX2_2(op2, &bitD2); + HUF_DECODE_SYMBOLX2_2(op3, &bitD3); + HUF_DECODE_SYMBOLX2_2(op4, &bitD4); + HUF_DECODE_SYMBOLX2_1(op1, &bitD1); + HUF_DECODE_SYMBOLX2_1(op2, &bitD2); + HUF_DECODE_SYMBOLX2_1(op3, &bitD3); + HUF_DECODE_SYMBOLX2_1(op4, &bitD4); + HUF_DECODE_SYMBOLX2_2(op1, &bitD1); + HUF_DECODE_SYMBOLX2_2(op2, &bitD2); + HUF_DECODE_SYMBOLX2_2(op3, &bitD3); + HUF_DECODE_SYMBOLX2_2(op4, &bitD4); + HUF_DECODE_SYMBOLX2_0(op1, &bitD1); + HUF_DECODE_SYMBOLX2_0(op2, &bitD2); + HUF_DECODE_SYMBOLX2_0(op3, &bitD3); + HUF_DECODE_SYMBOLX2_0(op4, &bitD4); + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + } + + /* check corruption */ + if (op1 > opStart2) + return ERROR(corruption_detected); + if (op2 > opStart3) + return ERROR(corruption_detected); + if (op3 > opStart4) + return ERROR(corruption_detected); + /* note : op4 supposed already verified within main loop */ + + /* finish bitStreams one by one */ + HUF_decodeStreamX2(op1, &bitD1, opStart2, dt, dtLog); + HUF_decodeStreamX2(op2, &bitD2, opStart3, dt, dtLog); + HUF_decodeStreamX2(op3, &bitD3, opStart4, dt, dtLog); + HUF_decodeStreamX2(op4, &bitD4, oend, dt, dtLog); + + /* check */ + endSignal = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4); + if (!endSignal) + return ERROR(corruption_detected); + + /* decoded size */ + return dstSize; + } +} + +size_t HUF_decompress4X2_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 0) + return ERROR(GENERIC); + return HUF_decompress4X2_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X2_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX2_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress4X2_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx); +} + +/* *************************/ +/* double-symbols decoding */ +/* *************************/ +typedef struct { + U16 sequence; + BYTE nbBits; + BYTE length; +} HUF_DEltX4; /* double-symbols decoding */ + +typedef struct { + BYTE symbol; + BYTE weight; +} sortedSymbol_t; + +/* HUF_fillDTableX4Level2() : + * `rankValOrigin` must be a table of at least (HUF_TABLELOG_MAX + 1) U32 */ +static void HUF_fillDTableX4Level2(HUF_DEltX4 *DTable, U32 sizeLog, const U32 consumed, const U32 *rankValOrigin, const int minWeight, + const sortedSymbol_t *sortedSymbols, const U32 sortedListSize, U32 nbBitsBaseline, U16 baseSeq) +{ + HUF_DEltX4 DElt; + U32 rankVal[HUF_TABLELOG_MAX + 1]; + + /* get pre-calculated rankVal */ + memcpy(rankVal, rankValOrigin, sizeof(rankVal)); + + /* fill skipped values */ + if (minWeight > 1) { + U32 i, skipSize = rankVal[minWeight]; + ZSTD_writeLE16(&(DElt.sequence), baseSeq); + DElt.nbBits = (BYTE)(consumed); + DElt.length = 1; + for (i = 0; i < skipSize; i++) + DTable[i] = DElt; + } + + /* fill DTable */ + { + U32 s; + for (s = 0; s < sortedListSize; s++) { /* note : sortedSymbols already skipped */ + const U32 symbol = sortedSymbols[s].symbol; + const U32 weight = sortedSymbols[s].weight; + const U32 nbBits = nbBitsBaseline - weight; + const U32 length = 1 << (sizeLog - nbBits); + const U32 start = rankVal[weight]; + U32 i = start; + const U32 end = start + length; + + ZSTD_writeLE16(&(DElt.sequence), (U16)(baseSeq + (symbol << 8))); + DElt.nbBits = (BYTE)(nbBits + consumed); + DElt.length = 2; + do { + DTable[i++] = DElt; + } while (i < end); /* since length >= 1 */ + + rankVal[weight] += length; + } + } +} + +typedef U32 rankVal_t[HUF_TABLELOG_MAX][HUF_TABLELOG_MAX + 1]; +typedef U32 rankValCol_t[HUF_TABLELOG_MAX + 1]; + +static void HUF_fillDTableX4(HUF_DEltX4 *DTable, const U32 targetLog, const sortedSymbol_t *sortedList, const U32 sortedListSize, const U32 *rankStart, + rankVal_t rankValOrigin, const U32 maxWeight, const U32 nbBitsBaseline) +{ + U32 rankVal[HUF_TABLELOG_MAX + 1]; + const int scaleLog = nbBitsBaseline - targetLog; /* note : targetLog >= srcLog, hence scaleLog <= 1 */ + const U32 minBits = nbBitsBaseline - maxWeight; + U32 s; + + memcpy(rankVal, rankValOrigin, sizeof(rankVal)); + + /* fill DTable */ + for (s = 0; s < sortedListSize; s++) { + const U16 symbol = sortedList[s].symbol; + const U32 weight = sortedList[s].weight; + const U32 nbBits = nbBitsBaseline - weight; + const U32 start = rankVal[weight]; + const U32 length = 1 << (targetLog - nbBits); + + if (targetLog - nbBits >= minBits) { /* enough room for a second symbol */ + U32 sortedRank; + int minWeight = nbBits + scaleLog; + if (minWeight < 1) + minWeight = 1; + sortedRank = rankStart[minWeight]; + HUF_fillDTableX4Level2(DTable + start, targetLog - nbBits, nbBits, rankValOrigin[nbBits], minWeight, sortedList + sortedRank, + sortedListSize - sortedRank, nbBitsBaseline, symbol); + } else { + HUF_DEltX4 DElt; + ZSTD_writeLE16(&(DElt.sequence), symbol); + DElt.nbBits = (BYTE)(nbBits); + DElt.length = 1; + { + U32 const end = start + length; + U32 u; + for (u = start; u < end; u++) + DTable[u] = DElt; + } + } + rankVal[weight] += length; + } +} + +size_t HUF_readDTableX4_wksp(HUF_DTable *DTable, const void *src, size_t srcSize, void *workspace, size_t workspaceSize) +{ + U32 tableLog, maxW, sizeOfSort, nbSymbols; + DTableDesc dtd = HUF_getDTableDesc(DTable); + U32 const maxTableLog = dtd.maxTableLog; + size_t iSize; + void *dtPtr = DTable + 1; /* force compiler to avoid strict-aliasing */ + HUF_DEltX4 *const dt = (HUF_DEltX4 *)dtPtr; + U32 *rankStart; + + rankValCol_t *rankVal; + U32 *rankStats; + U32 *rankStart0; + sortedSymbol_t *sortedSymbol; + BYTE *weightList; + size_t spaceUsed32 = 0; + + HUF_STATIC_ASSERT((sizeof(rankValCol_t) & 3) == 0); + + rankVal = (rankValCol_t *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += (sizeof(rankValCol_t) * HUF_TABLELOG_MAX) >> 2; + rankStats = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 1; + rankStart0 = (U32 *)workspace + spaceUsed32; + spaceUsed32 += HUF_TABLELOG_MAX + 2; + sortedSymbol = (sortedSymbol_t *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(sizeof(sortedSymbol_t) * (HUF_SYMBOLVALUE_MAX + 1), sizeof(U32)) >> 2; + weightList = (BYTE *)((U32 *)workspace + spaceUsed32); + spaceUsed32 += ALIGN(HUF_SYMBOLVALUE_MAX + 1, sizeof(U32)) >> 2; + + if ((spaceUsed32 << 2) > workspaceSize) + return ERROR(tableLog_tooLarge); + workspace = (U32 *)workspace + spaceUsed32; + workspaceSize -= (spaceUsed32 << 2); + + rankStart = rankStart0 + 1; + memset(rankStats, 0, sizeof(U32) * (2 * HUF_TABLELOG_MAX + 2 + 1)); + + HUF_STATIC_ASSERT(sizeof(HUF_DEltX4) == sizeof(HUF_DTable)); /* if compiler fails here, assertion is wrong */ + if (maxTableLog > HUF_TABLELOG_MAX) + return ERROR(tableLog_tooLarge); + /* memset(weightList, 0, sizeof(weightList)); */ /* is not necessary, even though some analyzer complain ... */ + + iSize = HUF_readStats_wksp(weightList, HUF_SYMBOLVALUE_MAX + 1, rankStats, &nbSymbols, &tableLog, src, srcSize, workspace, workspaceSize); + if (HUF_isError(iSize)) + return iSize; + + /* check result */ + if (tableLog > maxTableLog) + return ERROR(tableLog_tooLarge); /* DTable can't fit code depth */ + + /* find maxWeight */ + for (maxW = tableLog; rankStats[maxW] == 0; maxW--) { + } /* necessarily finds a solution before 0 */ + + /* Get start index of each weight */ + { + U32 w, nextRankStart = 0; + for (w = 1; w < maxW + 1; w++) { + U32 curr = nextRankStart; + nextRankStart += rankStats[w]; + rankStart[w] = curr; + } + rankStart[0] = nextRankStart; /* put all 0w symbols at the end of sorted list*/ + sizeOfSort = nextRankStart; + } + + /* sort symbols by weight */ + { + U32 s; + for (s = 0; s < nbSymbols; s++) { + U32 const w = weightList[s]; + U32 const r = rankStart[w]++; + sortedSymbol[r].symbol = (BYTE)s; + sortedSymbol[r].weight = (BYTE)w; + } + rankStart[0] = 0; /* forget 0w symbols; this is beginning of weight(1) */ + } + + /* Build rankVal */ + { + U32 *const rankVal0 = rankVal[0]; + { + int const rescale = (maxTableLog - tableLog) - 1; /* tableLog <= maxTableLog */ + U32 nextRankVal = 0; + U32 w; + for (w = 1; w < maxW + 1; w++) { + U32 curr = nextRankVal; + nextRankVal += rankStats[w] << (w + rescale); + rankVal0[w] = curr; + } + } + { + U32 const minBits = tableLog + 1 - maxW; + U32 consumed; + for (consumed = minBits; consumed < maxTableLog - minBits + 1; consumed++) { + U32 *const rankValPtr = rankVal[consumed]; + U32 w; + for (w = 1; w < maxW + 1; w++) { + rankValPtr[w] = rankVal0[w] >> consumed; + } + } + } + } + + HUF_fillDTableX4(dt, maxTableLog, sortedSymbol, sizeOfSort, rankStart0, rankVal, maxW, tableLog + 1); + + dtd.tableLog = (BYTE)maxTableLog; + dtd.tableType = 1; + memcpy(DTable, &dtd, sizeof(dtd)); + return iSize; +} + +static U32 HUF_decodeSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */ + memcpy(op, dt + val, 2); + BIT_skipBits(DStream, dt[val].nbBits); + return dt[val].length; +} + +static U32 HUF_decodeLastSymbolX4(void *op, BIT_DStream_t *DStream, const HUF_DEltX4 *dt, const U32 dtLog) +{ + size_t const val = BIT_lookBitsFast(DStream, dtLog); /* note : dtLog >= 1 */ + memcpy(op, dt + val, 1); + if (dt[val].length == 1) + BIT_skipBits(DStream, dt[val].nbBits); + else { + if (DStream->bitsConsumed < (sizeof(DStream->bitContainer) * 8)) { + BIT_skipBits(DStream, dt[val].nbBits); + if (DStream->bitsConsumed > (sizeof(DStream->bitContainer) * 8)) + /* ugly hack; works only because it's the last symbol. Note : can't easily extract nbBits from just this symbol */ + DStream->bitsConsumed = (sizeof(DStream->bitContainer) * 8); + } + } + return 1; +} + +#define HUF_DECODE_SYMBOLX4_0(ptr, DStreamPtr) ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX4_1(ptr, DStreamPtr) \ + if (ZSTD_64bits() || (HUF_TABLELOG_MAX <= 12)) \ + ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +#define HUF_DECODE_SYMBOLX4_2(ptr, DStreamPtr) \ + if (ZSTD_64bits()) \ + ptr += HUF_decodeSymbolX4(ptr, DStreamPtr, dt, dtLog) + +FORCE_INLINE size_t HUF_decodeStreamX4(BYTE *p, BIT_DStream_t *bitDPtr, BYTE *const pEnd, const HUF_DEltX4 *const dt, const U32 dtLog) +{ + BYTE *const pStart = p; + + /* up to 8 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p < pEnd - (sizeof(bitDPtr->bitContainer) - 1))) { + HUF_DECODE_SYMBOLX4_2(p, bitDPtr); + HUF_DECODE_SYMBOLX4_1(p, bitDPtr); + HUF_DECODE_SYMBOLX4_2(p, bitDPtr); + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); + } + + /* closer to end : up to 2 symbols at a time */ + while ((BIT_reloadDStream(bitDPtr) == BIT_DStream_unfinished) & (p <= pEnd - 2)) + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); + + while (p <= pEnd - 2) + HUF_DECODE_SYMBOLX4_0(p, bitDPtr); /* no need to reload : reached the end of DStream */ + + if (p < pEnd) + p += HUF_decodeLastSymbolX4(p, bitDPtr, dt, dtLog); + + return p - pStart; +} + +static size_t HUF_decompress1X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + BIT_DStream_t bitD; + + /* Init */ + { + size_t const errorCode = BIT_initDStream(&bitD, cSrc, cSrcSize); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* decode */ + { + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; /* force compiler to not use strict-aliasing */ + const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + HUF_decodeStreamX4(ostart, &bitD, oend, dt, dtd.tableLog); + } + + /* check */ + if (!BIT_endOfDStream(&bitD)) + return ERROR(corruption_detected); + + /* decoded size */ + return dstSize; +} + +size_t HUF_decompress1X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 1) + return ERROR(GENERIC); + return HUF_decompress1X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress1X4_DCtx_wksp(HUF_DTable *DCtx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t const hSize = HUF_readDTableX4_wksp(DCtx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress1X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, DCtx); +} + +static size_t HUF_decompress4X4_usingDTable_internal(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + if (cSrcSize < 10) + return ERROR(corruption_detected); /* strict minimum : jump table + 1 byte per stream */ + + { + const BYTE *const istart = (const BYTE *)cSrc; + BYTE *const ostart = (BYTE *)dst; + BYTE *const oend = ostart + dstSize; + const void *const dtPtr = DTable + 1; + const HUF_DEltX4 *const dt = (const HUF_DEltX4 *)dtPtr; + + /* Init */ + BIT_DStream_t bitD1; + BIT_DStream_t bitD2; + BIT_DStream_t bitD3; + BIT_DStream_t bitD4; + size_t const length1 = ZSTD_readLE16(istart); + size_t const length2 = ZSTD_readLE16(istart + 2); + size_t const length3 = ZSTD_readLE16(istart + 4); + size_t const length4 = cSrcSize - (length1 + length2 + length3 + 6); + const BYTE *const istart1 = istart + 6; /* jumpTable */ + const BYTE *const istart2 = istart1 + length1; + const BYTE *const istart3 = istart2 + length2; + const BYTE *const istart4 = istart3 + length3; + size_t const segmentSize = (dstSize + 3) / 4; + BYTE *const opStart2 = ostart + segmentSize; + BYTE *const opStart3 = opStart2 + segmentSize; + BYTE *const opStart4 = opStart3 + segmentSize; + BYTE *op1 = ostart; + BYTE *op2 = opStart2; + BYTE *op3 = opStart3; + BYTE *op4 = opStart4; + U32 endSignal; + DTableDesc const dtd = HUF_getDTableDesc(DTable); + U32 const dtLog = dtd.tableLog; + + if (length4 > cSrcSize) + return ERROR(corruption_detected); /* overflow */ + { + size_t const errorCode = BIT_initDStream(&bitD1, istart1, length1); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD2, istart2, length2); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD3, istart3, length3); + if (HUF_isError(errorCode)) + return errorCode; + } + { + size_t const errorCode = BIT_initDStream(&bitD4, istart4, length4); + if (HUF_isError(errorCode)) + return errorCode; + } + + /* 16-32 symbols per loop (4-8 symbols per stream) */ + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + for (; (endSignal == BIT_DStream_unfinished) & (op4 < (oend - (sizeof(bitD4.bitContainer) - 1)));) { + HUF_DECODE_SYMBOLX4_2(op1, &bitD1); + HUF_DECODE_SYMBOLX4_2(op2, &bitD2); + HUF_DECODE_SYMBOLX4_2(op3, &bitD3); + HUF_DECODE_SYMBOLX4_2(op4, &bitD4); + HUF_DECODE_SYMBOLX4_1(op1, &bitD1); + HUF_DECODE_SYMBOLX4_1(op2, &bitD2); + HUF_DECODE_SYMBOLX4_1(op3, &bitD3); + HUF_DECODE_SYMBOLX4_1(op4, &bitD4); + HUF_DECODE_SYMBOLX4_2(op1, &bitD1); + HUF_DECODE_SYMBOLX4_2(op2, &bitD2); + HUF_DECODE_SYMBOLX4_2(op3, &bitD3); + HUF_DECODE_SYMBOLX4_2(op4, &bitD4); + HUF_DECODE_SYMBOLX4_0(op1, &bitD1); + HUF_DECODE_SYMBOLX4_0(op2, &bitD2); + HUF_DECODE_SYMBOLX4_0(op3, &bitD3); + HUF_DECODE_SYMBOLX4_0(op4, &bitD4); + + endSignal = BIT_reloadDStream(&bitD1) | BIT_reloadDStream(&bitD2) | BIT_reloadDStream(&bitD3) | BIT_reloadDStream(&bitD4); + } + + /* check corruption */ + if (op1 > opStart2) + return ERROR(corruption_detected); + if (op2 > opStart3) + return ERROR(corruption_detected); + if (op3 > opStart4) + return ERROR(corruption_detected); + /* note : op4 already verified within main loop */ + + /* finish bitStreams one by one */ + HUF_decodeStreamX4(op1, &bitD1, opStart2, dt, dtLog); + HUF_decodeStreamX4(op2, &bitD2, opStart3, dt, dtLog); + HUF_decodeStreamX4(op3, &bitD3, opStart4, dt, dtLog); + HUF_decodeStreamX4(op4, &bitD4, oend, dt, dtLog); + + /* check */ + { + U32 const endCheck = BIT_endOfDStream(&bitD1) & BIT_endOfDStream(&bitD2) & BIT_endOfDStream(&bitD3) & BIT_endOfDStream(&bitD4); + if (!endCheck) + return ERROR(corruption_detected); + } + + /* decoded size */ + return dstSize; + } +} + +size_t HUF_decompress4X4_usingDTable(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc dtd = HUF_getDTableDesc(DTable); + if (dtd.tableType != 1) + return ERROR(GENERIC); + return HUF_decompress4X4_usingDTable_internal(dst, dstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X4_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + const BYTE *ip = (const BYTE *)cSrc; + + size_t hSize = HUF_readDTableX4_wksp(dctx, cSrc, cSrcSize, workspace, workspaceSize); + if (HUF_isError(hSize)) + return hSize; + if (hSize >= cSrcSize) + return ERROR(srcSize_wrong); + ip += hSize; + cSrcSize -= hSize; + + return HUF_decompress4X4_usingDTable_internal(dst, dstSize, ip, cSrcSize, dctx); +} + +/* ********************************/ +/* Generic decompression selector */ +/* ********************************/ + +size_t HUF_decompress1X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc const dtd = HUF_getDTableDesc(DTable); + return dtd.tableType ? HUF_decompress1X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable) + : HUF_decompress1X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable); +} + +size_t HUF_decompress4X_usingDTable(void *dst, size_t maxDstSize, const void *cSrc, size_t cSrcSize, const HUF_DTable *DTable) +{ + DTableDesc const dtd = HUF_getDTableDesc(DTable); + return dtd.tableType ? HUF_decompress4X4_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable) + : HUF_decompress4X2_usingDTable_internal(dst, maxDstSize, cSrc, cSrcSize, DTable); +} + +typedef struct { + U32 tableTime; + U32 decode256Time; +} algo_time_t; +static const algo_time_t algoTime[16 /* Quantization */][3 /* single, double, quad */] = { + /* single, double, quad */ + {{0, 0}, {1, 1}, {2, 2}}, /* Q==0 : impossible */ + {{0, 0}, {1, 1}, {2, 2}}, /* Q==1 : impossible */ + {{38, 130}, {1313, 74}, {2151, 38}}, /* Q == 2 : 12-18% */ + {{448, 128}, {1353, 74}, {2238, 41}}, /* Q == 3 : 18-25% */ + {{556, 128}, {1353, 74}, {2238, 47}}, /* Q == 4 : 25-32% */ + {{714, 128}, {1418, 74}, {2436, 53}}, /* Q == 5 : 32-38% */ + {{883, 128}, {1437, 74}, {2464, 61}}, /* Q == 6 : 38-44% */ + {{897, 128}, {1515, 75}, {2622, 68}}, /* Q == 7 : 44-50% */ + {{926, 128}, {1613, 75}, {2730, 75}}, /* Q == 8 : 50-56% */ + {{947, 128}, {1729, 77}, {3359, 77}}, /* Q == 9 : 56-62% */ + {{1107, 128}, {2083, 81}, {4006, 84}}, /* Q ==10 : 62-69% */ + {{1177, 128}, {2379, 87}, {4785, 88}}, /* Q ==11 : 69-75% */ + {{1242, 128}, {2415, 93}, {5155, 84}}, /* Q ==12 : 75-81% */ + {{1349, 128}, {2644, 106}, {5260, 106}}, /* Q ==13 : 81-87% */ + {{1455, 128}, {2422, 124}, {4174, 124}}, /* Q ==14 : 87-93% */ + {{722, 128}, {1891, 145}, {1936, 146}}, /* Q ==15 : 93-99% */ +}; + +/** HUF_selectDecoder() : +* Tells which decoder is likely to decode faster, +* based on a set of pre-determined metrics. +* @return : 0==HUF_decompress4X2, 1==HUF_decompress4X4 . +* Assumption : 0 < cSrcSize < dstSize <= 128 KB */ +U32 HUF_selectDecoder(size_t dstSize, size_t cSrcSize) +{ + /* decoder timing evaluation */ + U32 const Q = (U32)(cSrcSize * 16 / dstSize); /* Q < 16 since dstSize > cSrcSize */ + U32 const D256 = (U32)(dstSize >> 8); + U32 const DTime0 = algoTime[Q][0].tableTime + (algoTime[Q][0].decode256Time * D256); + U32 DTime1 = algoTime[Q][1].tableTime + (algoTime[Q][1].decode256Time * D256); + DTime1 += DTime1 >> 3; /* advantage to algorithm using less memory, for cache eviction */ + + return DTime1 < DTime0; +} + +typedef size_t (*decompressionAlgo)(void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize); + +size_t HUF_decompress4X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if (cSrcSize > dstSize) + return ERROR(corruption_detected); /* invalid */ + if (cSrcSize == dstSize) { + memcpy(dst, cSrc, dstSize); + return dstSize; + } /* not compressed */ + if (cSrcSize == 1) { + memset(dst, *(const BYTE *)cSrc, dstSize); + return dstSize; + } /* RLE */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} + +size_t HUF_decompress4X_hufOnly_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if ((cSrcSize >= dstSize) || (cSrcSize <= 1)) + return ERROR(corruption_detected); /* invalid */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress4X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress4X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} + +size_t HUF_decompress1X_DCtx_wksp(HUF_DTable *dctx, void *dst, size_t dstSize, const void *cSrc, size_t cSrcSize, void *workspace, size_t workspaceSize) +{ + /* validation checks */ + if (dstSize == 0) + return ERROR(dstSize_tooSmall); + if (cSrcSize > dstSize) + return ERROR(corruption_detected); /* invalid */ + if (cSrcSize == dstSize) { + memcpy(dst, cSrc, dstSize); + return dstSize; + } /* not compressed */ + if (cSrcSize == 1) { + memset(dst, *(const BYTE *)cSrc, dstSize); + return dstSize; + } /* RLE */ + + { + U32 const algoNb = HUF_selectDecoder(dstSize, cSrcSize); + return algoNb ? HUF_decompress1X4_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize) + : HUF_decompress1X2_DCtx_wksp(dctx, dst, dstSize, cSrc, cSrcSize, workspace, workspaceSize); + } +} diff --git a/xen/common/zstd/mem.h b/xen/common/zstd/mem.h new file mode 100644 index 0000000000..93d7a2c377 --- /dev/null +++ b/xen/common/zstd/mem.h @@ -0,0 +1,151 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +#ifndef MEM_H_MODULE +#define MEM_H_MODULE + +/*-**************************************** +* Dependencies +******************************************/ +#include +#include /* memcpy */ +#include /* size_t, ptrdiff_t */ + +/*-**************************************** +* Compiler specifics +******************************************/ +#define ZSTD_STATIC static inline + +/*-************************************************************** +* Basic Types +*****************************************************************/ +typedef uint8_t BYTE; +typedef uint16_t U16; +typedef int16_t S16; +typedef uint32_t U32; +typedef int32_t S32; +typedef uint64_t U64; +typedef int64_t S64; +typedef ptrdiff_t iPtrDiff; +typedef uintptr_t uPtrDiff; + +/*-************************************************************** +* Memory I/O +*****************************************************************/ +ZSTD_STATIC unsigned ZSTD_32bits(void) { return sizeof(size_t) == 4; } +ZSTD_STATIC unsigned ZSTD_64bits(void) { return sizeof(size_t) == 8; } + +#if defined(__LITTLE_ENDIAN) +#define ZSTD_LITTLE_ENDIAN 1 +#else +#define ZSTD_LITTLE_ENDIAN 0 +#endif + +ZSTD_STATIC unsigned ZSTD_isLittleEndian(void) { return ZSTD_LITTLE_ENDIAN; } + +ZSTD_STATIC U16 ZSTD_read16(const void *memPtr) { return get_unaligned((const U16 *)memPtr); } + +ZSTD_STATIC U32 ZSTD_read32(const void *memPtr) { return get_unaligned((const U32 *)memPtr); } + +ZSTD_STATIC U64 ZSTD_read64(const void *memPtr) { return get_unaligned((const U64 *)memPtr); } + +ZSTD_STATIC size_t ZSTD_readST(const void *memPtr) { return get_unaligned((const size_t *)memPtr); } + +ZSTD_STATIC void ZSTD_write16(void *memPtr, U16 value) { put_unaligned(value, (U16 *)memPtr); } + +ZSTD_STATIC void ZSTD_write32(void *memPtr, U32 value) { put_unaligned(value, (U32 *)memPtr); } + +ZSTD_STATIC void ZSTD_write64(void *memPtr, U64 value) { put_unaligned(value, (U64 *)memPtr); } + +/*=== Little endian r/w ===*/ + +ZSTD_STATIC U16 ZSTD_readLE16(const void *memPtr) { return get_unaligned_le16(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE16(void *memPtr, U16 val) { put_unaligned_le16(val, memPtr); } + +ZSTD_STATIC U32 ZSTD_readLE24(const void *memPtr) { return ZSTD_readLE16(memPtr) + (((const BYTE *)memPtr)[2] << 16); } + +ZSTD_STATIC void ZSTD_writeLE24(void *memPtr, U32 val) +{ + ZSTD_writeLE16(memPtr, (U16)val); + ((BYTE *)memPtr)[2] = (BYTE)(val >> 16); +} + +ZSTD_STATIC U32 ZSTD_readLE32(const void *memPtr) { return get_unaligned_le32(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE32(void *memPtr, U32 val32) { put_unaligned_le32(val32, memPtr); } + +ZSTD_STATIC U64 ZSTD_readLE64(const void *memPtr) { return get_unaligned_le64(memPtr); } + +ZSTD_STATIC void ZSTD_writeLE64(void *memPtr, U64 val64) { put_unaligned_le64(val64, memPtr); } + +ZSTD_STATIC size_t ZSTD_readLEST(const void *memPtr) +{ + if (ZSTD_32bits()) + return (size_t)ZSTD_readLE32(memPtr); + else + return (size_t)ZSTD_readLE64(memPtr); +} + +ZSTD_STATIC void ZSTD_writeLEST(void *memPtr, size_t val) +{ + if (ZSTD_32bits()) + ZSTD_writeLE32(memPtr, (U32)val); + else + ZSTD_writeLE64(memPtr, (U64)val); +} + +/*=== Big endian r/w ===*/ + +ZSTD_STATIC U32 ZSTD_readBE32(const void *memPtr) { return get_unaligned_be32(memPtr); } + +ZSTD_STATIC void ZSTD_writeBE32(void *memPtr, U32 val32) { put_unaligned_be32(val32, memPtr); } + +ZSTD_STATIC U64 ZSTD_readBE64(const void *memPtr) { return get_unaligned_be64(memPtr); } + +ZSTD_STATIC void ZSTD_writeBE64(void *memPtr, U64 val64) { put_unaligned_be64(val64, memPtr); } + +ZSTD_STATIC size_t ZSTD_readBEST(const void *memPtr) +{ + if (ZSTD_32bits()) + return (size_t)ZSTD_readBE32(memPtr); + else + return (size_t)ZSTD_readBE64(memPtr); +} + +ZSTD_STATIC void ZSTD_writeBEST(void *memPtr, size_t val) +{ + if (ZSTD_32bits()) + ZSTD_writeBE32(memPtr, (U32)val); + else + ZSTD_writeBE64(memPtr, (U64)val); +} + +/* function safe only for comparisons */ +ZSTD_STATIC U32 ZSTD_readMINMATCH(const void *memPtr, U32 length) +{ + switch (length) { + default: + case 4: return ZSTD_read32(memPtr); + case 3: + if (ZSTD_isLittleEndian()) + return ZSTD_read32(memPtr) << 8; + else + return ZSTD_read32(memPtr) >> 8; + } +} + +#endif /* MEM_H_MODULE */ diff --git a/xen/common/zstd/zstd_common.c b/xen/common/zstd/zstd_common.c new file mode 100644 index 0000000000..a282624ee1 --- /dev/null +++ b/xen/common/zstd/zstd_common.c @@ -0,0 +1,75 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/*-************************************* +* Dependencies +***************************************/ +#include "error_private.h" +#include "zstd_internal.h" /* declaration of ZSTD_isError, ZSTD_getErrorName, ZSTD_getErrorCode, ZSTD_getErrorString, ZSTD_versionNumber */ +#include + +/*=************************************************************** +* Custom allocator +****************************************************************/ + +#define stack_push(stack, size) \ + ({ \ + void *const ptr = ZSTD_PTR_ALIGN((stack)->ptr); \ + (stack)->ptr = (char *)ptr + (size); \ + (stack)->ptr <= (stack)->end ? ptr : NULL; \ + }) + +ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize) +{ + ZSTD_customMem stackMem = {ZSTD_stackAlloc, ZSTD_stackFree, workspace}; + ZSTD_stack *stack = (ZSTD_stack *)workspace; + /* Verify preconditions */ + if (!workspace || workspaceSize < sizeof(ZSTD_stack) || workspace != ZSTD_PTR_ALIGN(workspace)) { + ZSTD_customMem error = {NULL, NULL, NULL}; + return error; + } + /* Initialize the stack */ + stack->ptr = workspace; + stack->end = (char *)workspace + workspaceSize; + stack_push(stack, sizeof(ZSTD_stack)); + return stackMem; +} + +void *ZSTD_stackAllocAll(void *opaque, size_t *size) +{ + ZSTD_stack *stack = (ZSTD_stack *)opaque; + *size = (BYTE const *)stack->end - (BYTE *)ZSTD_PTR_ALIGN(stack->ptr); + return stack_push(stack, *size); +} + +void *ZSTD_stackAlloc(void *opaque, size_t size) +{ + ZSTD_stack *stack = (ZSTD_stack *)opaque; + return stack_push(stack, size); +} +void ZSTD_stackFree(void *opaque, void *address) +{ + (void)opaque; + (void)address; +} + +void *ZSTD_malloc(size_t size, ZSTD_customMem customMem) { return customMem.customAlloc(customMem.opaque, size); } + +void ZSTD_free(void *ptr, ZSTD_customMem customMem) +{ + if (ptr != NULL) + customMem.customFree(customMem.opaque, ptr); +} diff --git a/xen/common/zstd/zstd_internal.h b/xen/common/zstd/zstd_internal.h new file mode 100644 index 0000000000..dac753397f --- /dev/null +++ b/xen/common/zstd/zstd_internal.h @@ -0,0 +1,273 @@ +/** + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +#ifndef ZSTD_CCOMMON_H_MODULE +#define ZSTD_CCOMMON_H_MODULE + +/*-******************************************************* +* Compiler specifics +*********************************************************/ +#define FORCE_INLINE static __always_inline +#define FORCE_NOINLINE static noinline + +/*-************************************* +* Dependencies +***************************************/ +#include "error_private.h" +#include "mem.h" +#include +#include +#include +#include + +/*-************************************* +* shared macros +***************************************/ +#define MIN(a, b) ((a) < (b) ? (a) : (b)) +#define MAX(a, b) ((a) > (b) ? (a) : (b)) +#define CHECK_F(f) \ + { \ + size_t const errcod = f; \ + if (ERR_isError(errcod)) \ + return errcod; \ + } /* check and Forward error code */ +#define CHECK_E(f, e) \ + { \ + size_t const errcod = f; \ + if (ERR_isError(errcod)) \ + return ERROR(e); \ + } /* check and send Error code */ +#define ZSTD_STATIC_ASSERT(c) \ + { \ + enum { ZSTD_static_assert = 1 / (int)(!!(c)) }; \ + } + +/*-************************************* +* Common constants +***************************************/ +#define ZSTD_OPT_NUM (1 << 12) +#define ZSTD_DICT_MAGIC 0xEC30A437 /* v0.7+ */ + +#define ZSTD_REP_NUM 3 /* number of repcodes */ +#define ZSTD_REP_CHECK (ZSTD_REP_NUM) /* number of repcodes to check by the optimal parser */ +#define ZSTD_REP_MOVE (ZSTD_REP_NUM - 1) +#define ZSTD_REP_MOVE_OPT (ZSTD_REP_NUM) +static const U32 repStartValue[ZSTD_REP_NUM] = {1, 4, 8}; + +#define KB *(1 << 10) +#define MB *(1 << 20) +#define GB *(1U << 30) + +#define BIT7 128 +#define BIT6 64 +#define BIT5 32 +#define BIT4 16 +#define BIT1 2 +#define BIT0 1 + +#define ZSTD_WINDOWLOG_ABSOLUTEMIN 10 +static const size_t ZSTD_fcs_fieldSize[4] = {0, 2, 4, 8}; +static const size_t ZSTD_did_fieldSize[4] = {0, 1, 2, 4}; + +#define ZSTD_BLOCKHEADERSIZE 3 /* C standard doesn't allow `static const` variable to be init using another `static const` variable */ +static const size_t ZSTD_blockHeaderSize = ZSTD_BLOCKHEADERSIZE; +typedef enum { bt_raw, bt_rle, bt_compressed, bt_reserved } blockType_e; + +#define MIN_SEQUENCES_SIZE 1 /* nbSeq==0 */ +#define MIN_CBLOCK_SIZE (1 /*litCSize*/ + 1 /* RLE or RAW */ + MIN_SEQUENCES_SIZE /* nbSeq==0 */) /* for a non-null block */ + +#define HufLog 12 +typedef enum { set_basic, set_rle, set_compressed, set_repeat } symbolEncodingType_e; + +#define LONGNBSEQ 0x7F00 + +#define MINMATCH 3 +#define EQUAL_READ32 4 + +#define Litbits 8 +#define MaxLit ((1 << Litbits) - 1) +#define MaxML 52 +#define MaxLL 35 +#define MaxOff 28 +#define MaxSeq MAX(MaxLL, MaxML) /* Assumption : MaxOff < MaxLL,MaxML */ +#define MLFSELog 9 +#define LLFSELog 9 +#define OffFSELog 8 + +static const U32 LL_bits[MaxLL + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}; +static const S16 LL_defaultNorm[MaxLL + 1] = {4, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 1, 1, 1, 1, 1, -1, -1, -1, -1}; +#define LL_DEFAULTNORMLOG 6 /* for static allocation */ +static const U32 LL_defaultNormLog = LL_DEFAULTNORMLOG; + +static const U32 ML_bits[MaxML + 1] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 3, 3, 4, 4, 5, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16}; +static const S16 ML_defaultNorm[MaxML + 1] = {1, 4, 3, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, + 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1, -1, -1}; +#define ML_DEFAULTNORMLOG 6 /* for static allocation */ +static const U32 ML_defaultNormLog = ML_DEFAULTNORMLOG; + +static const S16 OF_defaultNorm[MaxOff + 1] = {1, 1, 1, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, -1, -1, -1, -1, -1}; +#define OF_DEFAULTNORMLOG 5 /* for static allocation */ +static const U32 OF_defaultNormLog = OF_DEFAULTNORMLOG; + +/*-******************************************* +* Shared functions to include for inlining +*********************************************/ +ZSTD_STATIC void ZSTD_copy8(void *dst, const void *src) { + /* + * zstd relies heavily on gcc being able to analyze and inline this + * memcpy() call, since it is called in a tight loop. Preboot mode + * is compiled in freestanding mode, which stops gcc from analyzing + * memcpy(). Use __builtin_memcpy() to tell gcc to analyze this as a + * regular memcpy(). + */ + __builtin_memcpy(dst, src, 8); +} +/*! ZSTD_wildcopy() : +* custom version of memcpy(), can copy up to 7 bytes too many (8 bytes if length==0) */ +#define WILDCOPY_OVERLENGTH 8 +ZSTD_STATIC void ZSTD_wildcopy(void *dst, const void *src, ptrdiff_t length) +{ + const BYTE* ip = (const BYTE*)src; + BYTE* op = (BYTE*)dst; + BYTE* const oend = op + length; +#if defined(GCC_VERSION) && GCC_VERSION >= 70000 && GCC_VERSION < 70200 + /* + * Work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81388. + * Avoid the bad case where the loop only runs once by handling the + * special case separately. This doesn't trigger the bug because it + * doesn't involve pointer/integer overflow. + */ + if (length <= 8) + return ZSTD_copy8(dst, src); +#endif + do { + ZSTD_copy8(op, ip); + op += 8; + ip += 8; + } while (op < oend); +} + +/*-******************************************* +* Private interfaces +*********************************************/ +typedef struct ZSTD_stats_s ZSTD_stats_t; + +typedef struct { + U32 off; + U32 len; +} ZSTD_match_t; + +typedef struct { + U32 price; + U32 off; + U32 mlen; + U32 litlen; + U32 rep[ZSTD_REP_NUM]; +} ZSTD_optimal_t; + +typedef struct seqDef_s { + U32 offset; + U16 litLength; + U16 matchLength; +} seqDef; + +typedef struct { + seqDef *sequencesStart; + seqDef *sequences; + BYTE *litStart; + BYTE *lit; + BYTE *llCode; + BYTE *mlCode; + BYTE *ofCode; + U32 longLengthID; /* 0 == no longLength; 1 == Lit.longLength; 2 == Match.longLength; */ + U32 longLengthPos; + /* opt */ + ZSTD_optimal_t *priceTable; + ZSTD_match_t *matchTable; + U32 *matchLengthFreq; + U32 *litLengthFreq; + U32 *litFreq; + U32 *offCodeFreq; + U32 matchLengthSum; + U32 matchSum; + U32 litLengthSum; + U32 litSum; + U32 offCodeSum; + U32 log2matchLengthSum; + U32 log2matchSum; + U32 log2litLengthSum; + U32 log2litSum; + U32 log2offCodeSum; + U32 factor; + U32 staticPrices; + U32 cachedPrice; + U32 cachedLitLength; + const BYTE *cachedLiterals; +} seqStore_t; + +const seqStore_t *ZSTD_getSeqStore(const ZSTD_CCtx *ctx); +void ZSTD_seqToCodes(const seqStore_t *seqStorePtr); +int ZSTD_isSkipFrame(ZSTD_DCtx *dctx); + +/*= Custom memory allocation functions */ +typedef void *(*ZSTD_allocFunction)(void *opaque, size_t size); +typedef void (*ZSTD_freeFunction)(void *opaque, void *address); +typedef struct { + ZSTD_allocFunction customAlloc; + ZSTD_freeFunction customFree; + void *opaque; +} ZSTD_customMem; + +void *ZSTD_malloc(size_t size, ZSTD_customMem customMem); +void ZSTD_free(void *ptr, ZSTD_customMem customMem); + +/*====== stack allocation ======*/ + +typedef struct { + void *ptr; + const void *end; +} ZSTD_stack; + +#define ZSTD_ALIGN(x) ALIGN(x, sizeof(size_t)) +#define ZSTD_PTR_ALIGN(p) PTR_ALIGN(p, sizeof(size_t)) + +ZSTD_customMem ZSTD_initStack(void *workspace, size_t workspaceSize); + +void *ZSTD_stackAllocAll(void *opaque, size_t *size); +void *ZSTD_stackAlloc(void *opaque, size_t size); +void ZSTD_stackFree(void *opaque, void *address); + +/*====== common function ======*/ + +ZSTD_STATIC U32 ZSTD_highbit32(U32 val) { return 31 - __builtin_clz(val); } + +/* hidden functions */ + +/* ZSTD_invalidateRepCodes() : + * ensures next compression will not use repcodes from previous block. + * Note : only works with regular variant; + * do not use with extDict variant ! */ +void ZSTD_invalidateRepCodes(ZSTD_CCtx *cctx); + +size_t ZSTD_freeCCtx(ZSTD_CCtx *cctx); +size_t ZSTD_freeDCtx(ZSTD_DCtx *dctx); +size_t ZSTD_freeCDict(ZSTD_CDict *cdict); +size_t ZSTD_freeDDict(ZSTD_DDict *cdict); +size_t ZSTD_freeCStream(ZSTD_CStream *zcs); +size_t ZSTD_freeDStream(ZSTD_DStream *zds); + +#endif /* ZSTD_CCOMMON_H_MODULE */ diff --git a/xen/common/zstd/zstd_opt.h b/xen/common/zstd/zstd_opt.h new file mode 100644 index 0000000000..55e1b4cba8 --- /dev/null +++ b/xen/common/zstd/zstd_opt.h @@ -0,0 +1,1014 @@ +/** + * Copyright (c) 2016-present, Przemyslaw Skibinski, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +/* Note : this file is intended to be included within zstd_compress.c */ + +#ifndef ZSTD_OPT_H_91842398743 +#define ZSTD_OPT_H_91842398743 + +#define ZSTD_LITFREQ_ADD 2 +#define ZSTD_FREQ_DIV 4 +#define ZSTD_MAX_PRICE (1 << 30) + +/*-************************************* +* Price functions for optimal parser +***************************************/ +FORCE_INLINE void ZSTD_setLog2Prices(seqStore_t *ssPtr) +{ + ssPtr->log2matchLengthSum = ZSTD_highbit32(ssPtr->matchLengthSum + 1); + ssPtr->log2litLengthSum = ZSTD_highbit32(ssPtr->litLengthSum + 1); + ssPtr->log2litSum = ZSTD_highbit32(ssPtr->litSum + 1); + ssPtr->log2offCodeSum = ZSTD_highbit32(ssPtr->offCodeSum + 1); + ssPtr->factor = 1 + ((ssPtr->litSum >> 5) / ssPtr->litLengthSum) + ((ssPtr->litSum << 1) / (ssPtr->litSum + ssPtr->matchSum)); +} + +ZSTD_STATIC void ZSTD_rescaleFreqs(seqStore_t *ssPtr, const BYTE *src, size_t srcSize) +{ + unsigned u; + + ssPtr->cachedLiterals = NULL; + ssPtr->cachedPrice = ssPtr->cachedLitLength = 0; + ssPtr->staticPrices = 0; + + if (ssPtr->litLengthSum == 0) { + if (srcSize <= 1024) + ssPtr->staticPrices = 1; + + for (u = 0; u <= MaxLit; u++) + ssPtr->litFreq[u] = 0; + for (u = 0; u < srcSize; u++) + ssPtr->litFreq[src[u]]++; + + ssPtr->litSum = 0; + ssPtr->litLengthSum = MaxLL + 1; + ssPtr->matchLengthSum = MaxML + 1; + ssPtr->offCodeSum = (MaxOff + 1); + ssPtr->matchSum = (ZSTD_LITFREQ_ADD << Litbits); + + for (u = 0; u <= MaxLit; u++) { + ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> ZSTD_FREQ_DIV); + ssPtr->litSum += ssPtr->litFreq[u]; + } + for (u = 0; u <= MaxLL; u++) + ssPtr->litLengthFreq[u] = 1; + for (u = 0; u <= MaxML; u++) + ssPtr->matchLengthFreq[u] = 1; + for (u = 0; u <= MaxOff; u++) + ssPtr->offCodeFreq[u] = 1; + } else { + ssPtr->matchLengthSum = 0; + ssPtr->litLengthSum = 0; + ssPtr->offCodeSum = 0; + ssPtr->matchSum = 0; + ssPtr->litSum = 0; + + for (u = 0; u <= MaxLit; u++) { + ssPtr->litFreq[u] = 1 + (ssPtr->litFreq[u] >> (ZSTD_FREQ_DIV + 1)); + ssPtr->litSum += ssPtr->litFreq[u]; + } + for (u = 0; u <= MaxLL; u++) { + ssPtr->litLengthFreq[u] = 1 + (ssPtr->litLengthFreq[u] >> (ZSTD_FREQ_DIV + 1)); + ssPtr->litLengthSum += ssPtr->litLengthFreq[u]; + } + for (u = 0; u <= MaxML; u++) { + ssPtr->matchLengthFreq[u] = 1 + (ssPtr->matchLengthFreq[u] >> ZSTD_FREQ_DIV); + ssPtr->matchLengthSum += ssPtr->matchLengthFreq[u]; + ssPtr->matchSum += ssPtr->matchLengthFreq[u] * (u + 3); + } + ssPtr->matchSum *= ZSTD_LITFREQ_ADD; + for (u = 0; u <= MaxOff; u++) { + ssPtr->offCodeFreq[u] = 1 + (ssPtr->offCodeFreq[u] >> ZSTD_FREQ_DIV); + ssPtr->offCodeSum += ssPtr->offCodeFreq[u]; + } + } + + ZSTD_setLog2Prices(ssPtr); +} + +FORCE_INLINE U32 ZSTD_getLiteralPrice(seqStore_t *ssPtr, U32 litLength, const BYTE *literals) +{ + U32 price, u; + + if (ssPtr->staticPrices) + return ZSTD_highbit32((U32)litLength + 1) + (litLength * 6); + + if (litLength == 0) + return ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[0] + 1); + + /* literals */ + if (ssPtr->cachedLiterals == literals) { + U32 const additional = litLength - ssPtr->cachedLitLength; + const BYTE *literals2 = ssPtr->cachedLiterals + ssPtr->cachedLitLength; + price = ssPtr->cachedPrice + additional * ssPtr->log2litSum; + for (u = 0; u < additional; u++) + price -= ZSTD_highbit32(ssPtr->litFreq[literals2[u]] + 1); + ssPtr->cachedPrice = price; + ssPtr->cachedLitLength = litLength; + } else { + price = litLength * ssPtr->log2litSum; + for (u = 0; u < litLength; u++) + price -= ZSTD_highbit32(ssPtr->litFreq[literals[u]] + 1); + + if (litLength >= 12) { + ssPtr->cachedLiterals = literals; + ssPtr->cachedPrice = price; + ssPtr->cachedLitLength = litLength; + } + } + + /* literal Length */ + { + const BYTE LL_deltaCode = 19; + const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength]; + price += LL_bits[llCode] + ssPtr->log2litLengthSum - ZSTD_highbit32(ssPtr->litLengthFreq[llCode] + 1); + } + + return price; +} + +FORCE_INLINE U32 ZSTD_getPrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength, const int ultra) +{ + /* offset */ + U32 price; + BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1); + + if (seqStorePtr->staticPrices) + return ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + ZSTD_highbit32((U32)matchLength + 1) + 16 + offCode; + + price = offCode + seqStorePtr->log2offCodeSum - ZSTD_highbit32(seqStorePtr->offCodeFreq[offCode] + 1); + if (!ultra && offCode >= 20) + price += (offCode - 19) * 2; + + /* match Length */ + { + const BYTE ML_deltaCode = 36; + const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength]; + price += ML_bits[mlCode] + seqStorePtr->log2matchLengthSum - ZSTD_highbit32(seqStorePtr->matchLengthFreq[mlCode] + 1); + } + + return price + ZSTD_getLiteralPrice(seqStorePtr, litLength, literals) + seqStorePtr->factor; +} + +ZSTD_STATIC void ZSTD_updatePrice(seqStore_t *seqStorePtr, U32 litLength, const BYTE *literals, U32 offset, U32 matchLength) +{ + U32 u; + + /* literals */ + seqStorePtr->litSum += litLength * ZSTD_LITFREQ_ADD; + for (u = 0; u < litLength; u++) + seqStorePtr->litFreq[literals[u]] += ZSTD_LITFREQ_ADD; + + /* literal Length */ + { + const BYTE LL_deltaCode = 19; + const BYTE llCode = (litLength > 63) ? (BYTE)ZSTD_highbit32(litLength) + LL_deltaCode : LL_Code[litLength]; + seqStorePtr->litLengthFreq[llCode]++; + seqStorePtr->litLengthSum++; + } + + /* match offset */ + { + BYTE const offCode = (BYTE)ZSTD_highbit32(offset + 1); + seqStorePtr->offCodeSum++; + seqStorePtr->offCodeFreq[offCode]++; + } + + /* match Length */ + { + const BYTE ML_deltaCode = 36; + const BYTE mlCode = (matchLength > 127) ? (BYTE)ZSTD_highbit32(matchLength) + ML_deltaCode : ML_Code[matchLength]; + seqStorePtr->matchLengthFreq[mlCode]++; + seqStorePtr->matchLengthSum++; + } + + ZSTD_setLog2Prices(seqStorePtr); +} + +#define SET_PRICE(pos, mlen_, offset_, litlen_, price_) \ + { \ + while (last_pos < pos) { \ + opt[last_pos + 1].price = ZSTD_MAX_PRICE; \ + last_pos++; \ + } \ + opt[pos].mlen = mlen_; \ + opt[pos].off = offset_; \ + opt[pos].litlen = litlen_; \ + opt[pos].price = price_; \ + } + +/* Update hashTable3 up to ip (excluded) + Assumption : always within prefix (i.e. not within extDict) */ +FORCE_INLINE +U32 ZSTD_insertAndFindFirstIndexHash3(ZSTD_CCtx *zc, const BYTE *ip) +{ + U32 *const hashTable3 = zc->hashTable3; + U32 const hashLog3 = zc->hashLog3; + const BYTE *const base = zc->base; + U32 idx = zc->nextToUpdate3; + const U32 target = zc->nextToUpdate3 = (U32)(ip - base); + const size_t hash3 = ZSTD_hash3Ptr(ip, hashLog3); + + while (idx < target) { + hashTable3[ZSTD_hash3Ptr(base + idx, hashLog3)] = idx; + idx++; + } + + return hashTable3[hash3]; +} + +/*-************************************* +* Binary Tree search +***************************************/ +static U32 ZSTD_insertBtAndGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, U32 nbCompares, const U32 mls, U32 extDict, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + const BYTE *const base = zc->base; + const U32 curr = (U32)(ip - base); + const U32 hashLog = zc->params.cParams.hashLog; + const size_t h = ZSTD_hashPtr(ip, hashLog, mls); + U32 *const hashTable = zc->hashTable; + U32 matchIndex = hashTable[h]; + U32 *const bt = zc->chainTable; + const U32 btLog = zc->params.cParams.chainLog - 1; + const U32 btMask = (1U << btLog) - 1; + size_t commonLengthSmaller = 0, commonLengthLarger = 0; + const BYTE *const dictBase = zc->dictBase; + const U32 dictLimit = zc->dictLimit; + const BYTE *const dictEnd = dictBase + dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const U32 btLow = btMask >= curr ? 0 : curr - btMask; + const U32 windowLow = zc->lowLimit; + U32 *smallerPtr = bt + 2 * (curr & btMask); + U32 *largerPtr = bt + 2 * (curr & btMask) + 1; + U32 matchEndIdx = curr + 8; + U32 dummy32; /* to be nullified at the end */ + U32 mnum = 0; + + const U32 minMatch = (mls == 3) ? 3 : 4; + size_t bestLength = minMatchLen - 1; + + if (minMatch == 3) { /* HC3 match finder */ + U32 const matchIndex3 = ZSTD_insertAndFindFirstIndexHash3(zc, ip); + if (matchIndex3 > windowLow && (curr - matchIndex3 < (1 << 18))) { + const BYTE *match; + size_t currMl = 0; + if ((!extDict) || matchIndex3 >= dictLimit) { + match = base + matchIndex3; + if (match[bestLength] == ip[bestLength]) + currMl = ZSTD_count(ip, match, iLimit); + } else { + match = dictBase + matchIndex3; + if (ZSTD_readMINMATCH(match, MINMATCH) == + ZSTD_readMINMATCH(ip, MINMATCH)) /* assumption : matchIndex3 <= dictLimit-4 (by table construction) */ + currMl = ZSTD_count_2segments(ip + MINMATCH, match + MINMATCH, iLimit, dictEnd, prefixStart) + MINMATCH; + } + + /* save best solution */ + if (currMl > bestLength) { + bestLength = currMl; + matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex3; + matches[mnum].len = (U32)currMl; + mnum++; + if (currMl > ZSTD_OPT_NUM) + goto update; + if (ip + currMl == iLimit) + goto update; /* best possible, and avoid read overflow*/ + } + } + } + + hashTable[h] = curr; /* Update Hash Table */ + + while (nbCompares-- && (matchIndex > windowLow)) { + U32 *nextPtr = bt + 2 * (matchIndex & btMask); + size_t matchLength = MIN(commonLengthSmaller, commonLengthLarger); /* guaranteed minimum nb of common bytes */ + const BYTE *match; + + if ((!extDict) || (matchIndex + matchLength >= dictLimit)) { + match = base + matchIndex; + if (match[matchLength] == ip[matchLength]) { + matchLength += ZSTD_count(ip + matchLength + 1, match + matchLength + 1, iLimit) + 1; + } + } else { + match = dictBase + matchIndex; + matchLength += ZSTD_count_2segments(ip + matchLength, match + matchLength, iLimit, dictEnd, prefixStart); + if (matchIndex + matchLength >= dictLimit) + match = base + matchIndex; /* to prepare for next usage of match[matchLength] */ + } + + if (matchLength > bestLength) { + if (matchLength > matchEndIdx - matchIndex) + matchEndIdx = matchIndex + (U32)matchLength; + bestLength = matchLength; + matches[mnum].off = ZSTD_REP_MOVE_OPT + curr - matchIndex; + matches[mnum].len = (U32)matchLength; + mnum++; + if (matchLength > ZSTD_OPT_NUM) + break; + if (ip + matchLength == iLimit) /* equal : no way to know if inf or sup */ + break; /* drop, to guarantee consistency (miss a little bit of compression) */ + } + + if (match[matchLength] < ip[matchLength]) { + /* match is smaller than curr */ + *smallerPtr = matchIndex; /* update smaller idx */ + commonLengthSmaller = matchLength; /* all smaller will now have at least this guaranteed common length */ + if (matchIndex <= btLow) { + smallerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + smallerPtr = nextPtr + 1; /* new "smaller" => larger of match */ + matchIndex = nextPtr[1]; /* new matchIndex larger than previous (closer to curr) */ + } else { + /* match is larger than curr */ + *largerPtr = matchIndex; + commonLengthLarger = matchLength; + if (matchIndex <= btLow) { + largerPtr = &dummy32; + break; + } /* beyond tree size, stop the search */ + largerPtr = nextPtr; + matchIndex = nextPtr[0]; + } + } + + *smallerPtr = *largerPtr = 0; + +update: + zc->nextToUpdate = (matchEndIdx > curr + 8) ? matchEndIdx - 8 : curr + 1; + return mnum; +} + +/** Tree updater, providing best match */ +static U32 ZSTD_BtGetAllMatches(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, ZSTD_match_t *matches, + const U32 minMatchLen) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 0, matches, minMatchLen); +} + +static U32 ZSTD_BtGetAllMatches_selectMLS(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + switch (matchLengthSearch) { + case 3: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen); + default: + case 4: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen); + case 5: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen); + case 7: + case 6: return ZSTD_BtGetAllMatches(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen); + } +} + +/** Tree updater, providing best match */ +static U32 ZSTD_BtGetAllMatches_extDict(ZSTD_CCtx *zc, const BYTE *const ip, const BYTE *const iLimit, const U32 maxNbAttempts, const U32 mls, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + if (ip < zc->base + zc->nextToUpdate) + return 0; /* skipped area */ + ZSTD_updateTree_extDict(zc, ip, iLimit, maxNbAttempts, mls); + return ZSTD_insertBtAndGetAllMatches(zc, ip, iLimit, maxNbAttempts, mls, 1, matches, minMatchLen); +} + +static U32 ZSTD_BtGetAllMatches_selectMLS_extDict(ZSTD_CCtx *zc, /* Index table will be updated */ + const BYTE *ip, const BYTE *const iHighLimit, const U32 maxNbAttempts, const U32 matchLengthSearch, + ZSTD_match_t *matches, const U32 minMatchLen) +{ + switch (matchLengthSearch) { + case 3: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 3, matches, minMatchLen); + default: + case 4: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 4, matches, minMatchLen); + case 5: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 5, matches, minMatchLen); + case 7: + case 6: return ZSTD_BtGetAllMatches_extDict(zc, ip, iHighLimit, maxNbAttempts, 6, matches, minMatchLen); + } +} + +/*-******************************* +* Optimal parser +*********************************/ +FORCE_INLINE +void ZSTD_compressBlock_opt_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base; + const BYTE *const prefixStart = base + ctx->dictLimit; + + const U32 maxSearches = 1U << ctx->params.cParams.searchLog; + const U32 sufficient_len = ctx->params.cParams.targetLength; + const U32 mls = ctx->params.cParams.searchLength; + const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4; + + ZSTD_optimal_t *opt = seqStorePtr->priceTable; + ZSTD_match_t *matches = seqStorePtr->matchTable; + const BYTE *inr; + U32 offset, rep[ZSTD_REP_NUM]; + + /* init */ + ctx->nextToUpdate3 = ctx->nextToUpdate; + ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize); + ip += (ip == prefixStart); + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + rep[i] = ctx->rep[i]; + } + + /* Match Loop */ + while (ip < ilimit) { + U32 cur, match_num, last_pos, litlen, price; + U32 u, mlen, best_mlen, best_off, litLength; + memset(opt, 0, sizeof(ZSTD_optimal_t)); + last_pos = 0; + litlen = (U32)(ip - anchor); + + /* check repCode */ + { + U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor); + for (i = (ip == anchor); i < last_i; i++) { + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i]; + if ((repCur > 0) && (repCur < (S32)(ip - prefixStart)) && + (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(ip - repCur, minMatch))) { + mlen = (U32)ZSTD_count(ip + minMatch, ip + minMatch - repCur, iend) + minMatch; + if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + best_off = i - (ip == anchor); + do { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */ + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, ip, iend, maxSearches, mls, matches, minMatch); + + if (!last_pos && !match_num) { + ip++; + continue; + } + + if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + + /* set prices using matches at position = 0 */ + best_mlen = (last_pos) ? last_pos : minMatch; + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + while (mlen <= best_mlen) { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, matches[u].off, litlen, price); /* note : macro modifies last_pos */ + mlen++; + } + } + + if (last_pos < minMatch) { + ip++; + continue; + } + + /* initialize opt[0] */ + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + opt[0].rep[i] = rep[i]; + } + opt[0].mlen = 1; + opt[0].litlen = litlen; + + /* check further positions */ + for (cur = 1; cur <= last_pos; cur++) { + inr = ip + cur; + + if (opt[cur - 1].mlen == 1) { + litlen = opt[cur - 1].litlen + 1; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen); + } else + price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor); + } else { + litlen = 1; + price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1); + } + + if (cur > last_pos || price <= opt[cur].price) + SET_PRICE(cur, 1, 0, litlen, price); + + if (cur == last_pos) + break; + + if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */ + continue; + + mlen = opt[cur].mlen; + if (opt[cur].off > ZSTD_REP_MOVE_OPT) { + opt[cur].rep[2] = opt[cur - mlen].rep[1]; + opt[cur].rep[1] = opt[cur - mlen].rep[0]; + opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT; + } else { + opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2]; + opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1]; + opt[cur].rep[0] = + ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]); + } + + best_mlen = minMatch; + { + U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1); + for (i = (opt[cur].mlen != 1); i < last_i; i++) { /* check rep */ + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i]; + if ((repCur > 0) && (repCur < (S32)(inr - prefixStart)) && + (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(inr - repCur, minMatch))) { + mlen = (U32)ZSTD_count(inr + minMatch, inr + minMatch - repCur, iend) + minMatch; + + if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + last_pos = cur + 1; + goto _storeSequence; + } + + best_off = i - (opt[cur].mlen != 1); + if (mlen > best_mlen) + best_mlen = mlen; + + do { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen, + best_off, mlen - MINMATCH, ultra); + } else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || price <= opt[cur + mlen].price) + SET_PRICE(cur + mlen, mlen, i, litlen, price); + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS(ctx, inr, iend, maxSearches, mls, matches, best_mlen); + + if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + last_pos = cur + 1; + goto _storeSequence; + } + + /* set prices using matches at position = cur */ + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + + while (mlen <= best_mlen) { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen, + matches[u].off - 1, mlen - MINMATCH, ultra); + else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || (price < opt[cur + mlen].price)) + SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price); + + mlen++; + } + } + } + + best_mlen = opt[last_pos].mlen; + best_off = opt[last_pos].off; + cur = last_pos - best_mlen; + + /* store sequence */ +_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */ + opt[0].mlen = 1; + + while (1) { + mlen = opt[cur].mlen; + offset = opt[cur].off; + opt[cur].mlen = best_mlen; + opt[cur].off = best_off; + best_mlen = mlen; + best_off = offset; + if (mlen > cur) + break; + cur -= mlen; + } + + for (u = 0; u <= last_pos;) { + u += opt[u].mlen; + } + + for (cur = 0; cur < last_pos;) { + mlen = opt[cur].mlen; + if (mlen == 1) { + ip++; + cur++; + continue; + } + offset = opt[cur].off; + cur += mlen; + litLength = (U32)(ip - anchor); + + if (offset > ZSTD_REP_MOVE_OPT) { + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = offset - ZSTD_REP_MOVE_OPT; + offset--; + } else { + if (offset != 0) { + best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]); + if (offset != 1) + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = best_off; + } + if (litLength == 0) + offset--; + } + + ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + anchor = ip = ip + mlen; + } + } /* for (cur=0; cur < last_pos; ) */ + + /* Save reps for next block */ + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + ctx->repToConfirm[i] = rep[i]; + } + + /* Last Literals */ + { + size_t const lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +FORCE_INLINE +void ZSTD_compressBlock_opt_extDict_generic(ZSTD_CCtx *ctx, const void *src, size_t srcSize, const int ultra) +{ + seqStore_t *seqStorePtr = &(ctx->seqStore); + const BYTE *const istart = (const BYTE *)src; + const BYTE *ip = istart; + const BYTE *anchor = istart; + const BYTE *const iend = istart + srcSize; + const BYTE *const ilimit = iend - 8; + const BYTE *const base = ctx->base; + const U32 lowestIndex = ctx->lowLimit; + const U32 dictLimit = ctx->dictLimit; + const BYTE *const prefixStart = base + dictLimit; + const BYTE *const dictBase = ctx->dictBase; + const BYTE *const dictEnd = dictBase + dictLimit; + + const U32 maxSearches = 1U << ctx->params.cParams.searchLog; + const U32 sufficient_len = ctx->params.cParams.targetLength; + const U32 mls = ctx->params.cParams.searchLength; + const U32 minMatch = (ctx->params.cParams.searchLength == 3) ? 3 : 4; + + ZSTD_optimal_t *opt = seqStorePtr->priceTable; + ZSTD_match_t *matches = seqStorePtr->matchTable; + const BYTE *inr; + + /* init */ + U32 offset, rep[ZSTD_REP_NUM]; + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + rep[i] = ctx->rep[i]; + } + + ctx->nextToUpdate3 = ctx->nextToUpdate; + ZSTD_rescaleFreqs(seqStorePtr, (const BYTE *)src, srcSize); + ip += (ip == prefixStart); + + /* Match Loop */ + while (ip < ilimit) { + U32 cur, match_num, last_pos, litlen, price; + U32 u, mlen, best_mlen, best_off, litLength; + U32 curr = (U32)(ip - base); + memset(opt, 0, sizeof(ZSTD_optimal_t)); + last_pos = 0; + opt[0].litlen = (U32)(ip - anchor); + + /* check repCode */ + { + U32 i, last_i = ZSTD_REP_CHECK + (ip == anchor); + for (i = (ip == anchor); i < last_i; i++) { + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : rep[i]; + const U32 repIndex = (U32)(curr - repCur); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if ((repCur > 0 && repCur <= (S32)curr) && + (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + && (ZSTD_readMINMATCH(ip, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) { + /* repcode detected we should take it */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + mlen = (U32)ZSTD_count_2segments(ip + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch; + + if (mlen > sufficient_len || mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + + best_off = i - (ip == anchor); + litlen = opt[0].litlen; + do { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, i, litlen, price); /* note : macro modifies last_pos */ + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, ip, iend, maxSearches, mls, matches, minMatch); /* first search (depth 0) */ + + if (!last_pos && !match_num) { + ip++; + continue; + } + + { + U32 i; + for (i = 0; i < ZSTD_REP_NUM; i++) + opt[0].rep[i] = rep[i]; + } + opt[0].mlen = 1; + + if (match_num && (matches[match_num - 1].len > sufficient_len || matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + cur = 0; + last_pos = 1; + goto _storeSequence; + } + + best_mlen = (last_pos) ? last_pos : minMatch; + + /* set prices using matches at position = 0 */ + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + litlen = opt[0].litlen; + while (mlen <= best_mlen) { + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + if (mlen > last_pos || price < opt[mlen].price) + SET_PRICE(mlen, mlen, matches[u].off, litlen, price); + mlen++; + } + } + + if (last_pos < minMatch) { + ip++; + continue; + } + + /* check further positions */ + for (cur = 1; cur <= last_pos; cur++) { + inr = ip + cur; + + if (opt[cur - 1].mlen == 1) { + litlen = opt[cur - 1].litlen + 1; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - litlen); + } else + price = ZSTD_getLiteralPrice(seqStorePtr, litlen, anchor); + } else { + litlen = 1; + price = opt[cur - 1].price + ZSTD_getLiteralPrice(seqStorePtr, litlen, inr - 1); + } + + if (cur > last_pos || price <= opt[cur].price) + SET_PRICE(cur, 1, 0, litlen, price); + + if (cur == last_pos) + break; + + if (inr > ilimit) /* last match must start at a minimum distance of 8 from oend */ + continue; + + mlen = opt[cur].mlen; + if (opt[cur].off > ZSTD_REP_MOVE_OPT) { + opt[cur].rep[2] = opt[cur - mlen].rep[1]; + opt[cur].rep[1] = opt[cur - mlen].rep[0]; + opt[cur].rep[0] = opt[cur].off - ZSTD_REP_MOVE_OPT; + } else { + opt[cur].rep[2] = (opt[cur].off > 1) ? opt[cur - mlen].rep[1] : opt[cur - mlen].rep[2]; + opt[cur].rep[1] = (opt[cur].off > 0) ? opt[cur - mlen].rep[0] : opt[cur - mlen].rep[1]; + opt[cur].rep[0] = + ((opt[cur].off == ZSTD_REP_MOVE_OPT) && (mlen != 1)) ? (opt[cur - mlen].rep[0] - 1) : (opt[cur - mlen].rep[opt[cur].off]); + } + + best_mlen = minMatch; + { + U32 i, last_i = ZSTD_REP_CHECK + (mlen != 1); + for (i = (mlen != 1); i < last_i; i++) { + const S32 repCur = (i == ZSTD_REP_MOVE_OPT) ? (opt[cur].rep[0] - 1) : opt[cur].rep[i]; + const U32 repIndex = (U32)(curr + cur - repCur); + const BYTE *const repBase = repIndex < dictLimit ? dictBase : base; + const BYTE *const repMatch = repBase + repIndex; + if ((repCur > 0 && repCur <= (S32)(curr + cur)) && + (((U32)((dictLimit - 1) - repIndex) >= 3) & (repIndex > lowestIndex)) /* intentional overflow */ + && (ZSTD_readMINMATCH(inr, minMatch) == ZSTD_readMINMATCH(repMatch, minMatch))) { + /* repcode detected */ + const BYTE *const repEnd = repIndex < dictLimit ? dictEnd : iend; + mlen = (U32)ZSTD_count_2segments(inr + minMatch, repMatch + minMatch, iend, repEnd, prefixStart) + minMatch; + + if (mlen > sufficient_len || cur + mlen >= ZSTD_OPT_NUM) { + best_mlen = mlen; + best_off = i; + last_pos = cur + 1; + goto _storeSequence; + } + + best_off = i - (opt[cur].mlen != 1); + if (mlen > best_mlen) + best_mlen = mlen; + + do { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) { + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, inr - litlen, + best_off, mlen - MINMATCH, ultra); + } else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, best_off, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, best_off, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || price <= opt[cur + mlen].price) + SET_PRICE(cur + mlen, mlen, i, litlen, price); + mlen--; + } while (mlen >= minMatch); + } + } + } + + match_num = ZSTD_BtGetAllMatches_selectMLS_extDict(ctx, inr, iend, maxSearches, mls, matches, minMatch); + + if (match_num > 0 && (matches[match_num - 1].len > sufficient_len || cur + matches[match_num - 1].len >= ZSTD_OPT_NUM)) { + best_mlen = matches[match_num - 1].len; + best_off = matches[match_num - 1].off; + last_pos = cur + 1; + goto _storeSequence; + } + + /* set prices using matches at position = cur */ + for (u = 0; u < match_num; u++) { + mlen = (u > 0) ? matches[u - 1].len + 1 : best_mlen; + best_mlen = matches[u].len; + + while (mlen <= best_mlen) { + if (opt[cur].mlen == 1) { + litlen = opt[cur].litlen; + if (cur > litlen) + price = opt[cur - litlen].price + ZSTD_getPrice(seqStorePtr, litlen, ip + cur - litlen, + matches[u].off - 1, mlen - MINMATCH, ultra); + else + price = ZSTD_getPrice(seqStorePtr, litlen, anchor, matches[u].off - 1, mlen - MINMATCH, ultra); + } else { + litlen = 0; + price = opt[cur].price + ZSTD_getPrice(seqStorePtr, 0, NULL, matches[u].off - 1, mlen - MINMATCH, ultra); + } + + if (cur + mlen > last_pos || (price < opt[cur + mlen].price)) + SET_PRICE(cur + mlen, mlen, matches[u].off, litlen, price); + + mlen++; + } + } + } /* for (cur = 1; cur <= last_pos; cur++) */ + + best_mlen = opt[last_pos].mlen; + best_off = opt[last_pos].off; + cur = last_pos - best_mlen; + + /* store sequence */ +_storeSequence: /* cur, last_pos, best_mlen, best_off have to be set */ + opt[0].mlen = 1; + + while (1) { + mlen = opt[cur].mlen; + offset = opt[cur].off; + opt[cur].mlen = best_mlen; + opt[cur].off = best_off; + best_mlen = mlen; + best_off = offset; + if (mlen > cur) + break; + cur -= mlen; + } + + for (u = 0; u <= last_pos;) { + u += opt[u].mlen; + } + + for (cur = 0; cur < last_pos;) { + mlen = opt[cur].mlen; + if (mlen == 1) { + ip++; + cur++; + continue; + } + offset = opt[cur].off; + cur += mlen; + litLength = (U32)(ip - anchor); + + if (offset > ZSTD_REP_MOVE_OPT) { + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = offset - ZSTD_REP_MOVE_OPT; + offset--; + } else { + if (offset != 0) { + best_off = (offset == ZSTD_REP_MOVE_OPT) ? (rep[0] - 1) : (rep[offset]); + if (offset != 1) + rep[2] = rep[1]; + rep[1] = rep[0]; + rep[0] = best_off; + } + + if (litLength == 0) + offset--; + } + + ZSTD_updatePrice(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + ZSTD_storeSeq(seqStorePtr, litLength, anchor, offset, mlen - MINMATCH); + anchor = ip = ip + mlen; + } + } /* for (cur=0; cur < last_pos; ) */ + + /* Save reps for next block */ + { + int i; + for (i = 0; i < ZSTD_REP_NUM; i++) + ctx->repToConfirm[i] = rep[i]; + } + + /* Last Literals */ + { + size_t lastLLSize = iend - anchor; + memcpy(seqStorePtr->lit, anchor, lastLLSize); + seqStorePtr->lit += lastLLSize; + } +} + +#endif /* ZSTD_OPT_H_91842398743 */ diff --git a/xen/include/xen/xxhash.h b/xen/include/xen/xxhash.h new file mode 100644 index 0000000000..df42511438 --- /dev/null +++ b/xen/include/xen/xxhash.h @@ -0,0 +1,259 @@ +/* + * xxHash - Extremely Fast Hash algorithm + * Copyright (C) 2012-2016, Yann Collet. + * + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + * + * You can contact the author at: + * - xxHash homepage: https://cyan4973.github.io/xxHash/ + * - xxHash source repository: https://github.com/Cyan4973/xxHash + */ + +/* + * Notice extracted from xxHash homepage: + * + * xxHash is an extremely fast Hash algorithm, running at RAM speed limits. + * It also successfully passes all tests from the SMHasher suite. + * + * Comparison (single thread, Windows Seven 32 bits, using SMHasher on a Core 2 + * Duo @3GHz) + * + * Name Speed Q.Score Author + * xxHash 5.4 GB/s 10 + * CrapWow 3.2 GB/s 2 Andrew + * MumurHash 3a 2.7 GB/s 10 Austin Appleby + * SpookyHash 2.0 GB/s 10 Bob Jenkins + * SBox 1.4 GB/s 9 Bret Mulvey + * Lookup3 1.2 GB/s 9 Bob Jenkins + * SuperFastHash 1.2 GB/s 1 Paul Hsieh + * CityHash64 1.05 GB/s 10 Pike & Alakuijala + * FNV 0.55 GB/s 5 Fowler, Noll, Vo + * CRC32 0.43 GB/s 9 + * MD5-32 0.33 GB/s 10 Ronald L. Rivest + * SHA1-32 0.28 GB/s 10 + * + * Q.Score is a measure of quality of the hash function. + * It depends on successfully passing SMHasher test set. + * 10 is a perfect score. + * + * A 64-bits version, named xxh64 offers much better speed, + * but for 64-bits applications only. + * Name Speed on 64 bits Speed on 32 bits + * xxh64 13.8 GB/s 1.9 GB/s + * xxh32 6.8 GB/s 6.0 GB/s + */ + +#ifndef XXHASH_H +#define XXHASH_H + +#include + +/*-**************************** + * Simple Hash Functions + *****************************/ + +/** + * xxh32() - calculate the 32-bit hash of the input with a given seed. + * + * @input: The data to hash. + * @length: The length of the data to hash. + * @seed: The seed can be used to alter the result predictably. + * + * Speed on Core 2 Duo @ 3 GHz (single thread, SMHasher benchmark) : 5.4 GB/s + * + * Return: The 32-bit hash of the data. + */ +uint32_t xxh32(const void *input, size_t length, uint32_t seed); + +/** + * xxh64() - calculate the 64-bit hash of the input with a given seed. + * + * @input: The data to hash. + * @length: The length of the data to hash. + * @seed: The seed can be used to alter the result predictably. + * + * This function runs 2x faster on 64-bit systems, but slower on 32-bit systems. + * + * Return: The 64-bit hash of the data. + */ +uint64_t xxh64(const void *input, size_t length, uint64_t seed); + +/** + * xxhash() - calculate wordsize hash of the input with a given seed + * @input: The data to hash. + * @length: The length of the data to hash. + * @seed: The seed can be used to alter the result predictably. + * + * If the hash does not need to be comparable between machines with + * different word sizes, this function will call whichever of xxh32() + * or xxh64() is faster. + * + * Return: wordsize hash of the data. + */ + +static inline unsigned long xxhash(const void *input, size_t length, + uint64_t seed) +{ +#if BITS_PER_LONG == 64 + return xxh64(input, length, seed); +#else + return xxh32(input, length, seed); +#endif +} + +/*-**************************** + * Streaming Hash Functions + *****************************/ + +/* + * These definitions are only meant to allow allocation of XXH state + * statically, on stack, or in a struct for example. + * Do not use members directly. + */ + +/** + * struct xxh32_state - private xxh32 state, do not use members directly + */ +struct xxh32_state { + uint32_t total_len_32; + uint32_t large_len; + uint32_t v1; + uint32_t v2; + uint32_t v3; + uint32_t v4; + uint32_t mem32[4]; + uint32_t memsize; +}; + +/** + * struct xxh32_state - private xxh64 state, do not use members directly + */ +struct xxh64_state { + uint64_t total_len; + uint64_t v1; + uint64_t v2; + uint64_t v3; + uint64_t v4; + uint64_t mem64[4]; + uint32_t memsize; +}; + +/** + * xxh32_reset() - reset the xxh32 state to start a new hashing operation + * + * @state: The xxh32 state to reset. + * @seed: Initialize the hash state with this seed. + * + * Call this function on any xxh32_state to prepare for a new hashing operation. + */ +void xxh32_reset(struct xxh32_state *state, uint32_t seed); + +/** + * xxh32_update() - hash the data given and update the xxh32 state + * + * @state: The xxh32 state to update. + * @input: The data to hash. + * @length: The length of the data to hash. + * + * After calling xxh32_reset() call xxh32_update() as many times as necessary. + * + * Return: Zero on success, otherwise an error code. + */ +int xxh32_update(struct xxh32_state *state, const void *input, size_t length); + +/** + * xxh32_digest() - produce the current xxh32 hash + * + * @state: Produce the current xxh32 hash of this state. + * + * A hash value can be produced at any time. It is still possible to continue + * inserting input into the hash state after a call to xxh32_digest(), and + * generate new hashes later on, by calling xxh32_digest() again. + * + * Return: The xxh32 hash stored in the state. + */ +uint32_t xxh32_digest(const struct xxh32_state *state); + +/** + * xxh64_reset() - reset the xxh64 state to start a new hashing operation + * + * @state: The xxh64 state to reset. + * @seed: Initialize the hash state with this seed. + */ +void xxh64_reset(struct xxh64_state *state, uint64_t seed); + +/** + * xxh64_update() - hash the data given and update the xxh64 state + * @state: The xxh64 state to update. + * @input: The data to hash. + * @length: The length of the data to hash. + * + * After calling xxh64_reset() call xxh64_update() as many times as necessary. + * + * Return: Zero on success, otherwise an error code. + */ +int xxh64_update(struct xxh64_state *state, const void *input, size_t length); + +/** + * xxh64_digest() - produce the current xxh64 hash + * + * @state: Produce the current xxh64 hash of this state. + * + * A hash value can be produced at any time. It is still possible to continue + * inserting input into the hash state after a call to xxh64_digest(), and + * generate new hashes later on, by calling xxh64_digest() again. + * + * Return: The xxh64 hash stored in the state. + */ +uint64_t xxh64_digest(const struct xxh64_state *state); + +/*-************************** + * Utils + ***************************/ + +/** + * xxh32_copy_state() - copy the source state into the destination state + * + * @src: The source xxh32 state. + * @dst: The destination xxh32 state. + */ +void xxh32_copy_state(struct xxh32_state *dst, const struct xxh32_state *src); + +/** + * xxh64_copy_state() - copy the source state into the destination state + * + * @src: The source xxh64 state. + * @dst: The destination xxh64 state. + */ +void xxh64_copy_state(struct xxh64_state *dst, const struct xxh64_state *src); + +#endif /* XXHASH_H */ diff --git a/xen/include/xen/zstd.h b/xen/include/xen/zstd.h new file mode 100644 index 0000000000..249575e248 --- /dev/null +++ b/xen/include/xen/zstd.h @@ -0,0 +1,1157 @@ +/* + * Copyright (c) 2016-present, Yann Collet, Facebook, Inc. + * All rights reserved. + * + * This source code is licensed under the BSD-style license found in the + * LICENSE file in the root directory of https://github.com/facebook/zstd. + * An additional grant of patent rights can be found in the PATENTS file in the + * same directory. + * + * This program is free software; you can redistribute it and/or modify it under + * the terms of the GNU General Public License version 2 as published by the + * Free Software Foundation. This program is dual-licensed; you may select + * either version 2 of the GNU General Public License ("GPL") or BSD license + * ("BSD"). + */ + +#ifndef ZSTD_H +#define ZSTD_H + +/* ====== Dependency ======*/ +#include /* size_t */ + + +/*-***************************************************************************** + * Introduction + * + * zstd, short for Zstandard, is a fast lossless compression algorithm, + * targeting real-time compression scenarios at zlib-level and better + * compression ratios. The zstd compression library provides in-memory + * compression and decompression functions. The library supports compression + * levels from 1 up to ZSTD_maxCLevel() which is 22. Levels >= 20, labeled + * ultra, should be used with caution, as they require more memory. + * Compression can be done in: + * - a single step, reusing a context (described as Explicit memory management) + * - unbounded multiple steps (described as Streaming compression) + * The compression ratio achievable on small data can be highly improved using + * compression with a dictionary in: + * - a single step (described as Simple dictionary API) + * - a single step, reusing a dictionary (described as Fast dictionary API) + ******************************************************************************/ + +/*====== Helper functions ======*/ + +/** + * enum ZSTD_ErrorCode - zstd error codes + * + * Functions that return size_t can be checked for errors using ZSTD_isError() + * and the ZSTD_ErrorCode can be extracted using ZSTD_getErrorCode(). + */ +typedef enum { + ZSTD_error_no_error, + ZSTD_error_GENERIC, + ZSTD_error_prefix_unknown, + ZSTD_error_version_unsupported, + ZSTD_error_parameter_unknown, + ZSTD_error_frameParameter_unsupported, + ZSTD_error_frameParameter_unsupportedBy32bits, + ZSTD_error_frameParameter_windowTooLarge, + ZSTD_error_compressionParameter_unsupported, + ZSTD_error_init_missing, + ZSTD_error_memory_allocation, + ZSTD_error_stage_wrong, + ZSTD_error_dstSize_tooSmall, + ZSTD_error_srcSize_wrong, + ZSTD_error_corruption_detected, + ZSTD_error_checksum_wrong, + ZSTD_error_tableLog_tooLarge, + ZSTD_error_maxSymbolValue_tooLarge, + ZSTD_error_maxSymbolValue_tooSmall, + ZSTD_error_dictionary_corrupted, + ZSTD_error_dictionary_wrong, + ZSTD_error_dictionaryCreation_failed, + ZSTD_error_maxCode +} ZSTD_ErrorCode; + +/** + * ZSTD_maxCLevel() - maximum compression level available + * + * Return: Maximum compression level available. + */ +int ZSTD_maxCLevel(void); +/** + * ZSTD_compressBound() - maximum compressed size in worst case scenario + * @srcSize: The size of the data to compress. + * + * Return: The maximum compressed size in the worst case scenario. + */ +size_t ZSTD_compressBound(size_t srcSize); +/** + * ZSTD_isError() - tells if a size_t function result is an error code + * @code: The function result to check for error. + * + * Return: Non-zero iff the code is an error. + */ +static __attribute__((unused)) unsigned int ZSTD_isError(size_t code) +{ + return code > (size_t)-ZSTD_error_maxCode; +} +/** + * ZSTD_getErrorCode() - translates an error function result to a ZSTD_ErrorCode + * @functionResult: The result of a function for which ZSTD_isError() is true. + * + * Return: The ZSTD_ErrorCode corresponding to the functionResult or 0 + * if the functionResult isn't an error. + */ +static __attribute__((unused)) ZSTD_ErrorCode ZSTD_getErrorCode( + size_t functionResult) +{ + if (!ZSTD_isError(functionResult)) + return (ZSTD_ErrorCode)0; + return (ZSTD_ErrorCode)(0 - functionResult); +} + +/** + * enum ZSTD_strategy - zstd compression search strategy + * + * From faster to stronger. + */ +typedef enum { + ZSTD_fast, + ZSTD_dfast, + ZSTD_greedy, + ZSTD_lazy, + ZSTD_lazy2, + ZSTD_btlazy2, + ZSTD_btopt, + ZSTD_btopt2 +} ZSTD_strategy; + +/** + * struct ZSTD_compressionParameters - zstd compression parameters + * @windowLog: Log of the largest match distance. Larger means more + * compression, and more memory needed during decompression. + * @chainLog: Fully searched segment. Larger means more compression, slower, + * and more memory (useless for fast). + * @hashLog: Dispatch table. Larger means more compression, + * slower, and more memory. + * @searchLog: Number of searches. Larger means more compression and slower. + * @searchLength: Match length searched. Larger means faster decompression, + * sometimes less compression. + * @targetLength: Acceptable match size for optimal parser (only). Larger means + * more compression, and slower. + * @strategy: The zstd compression strategy. + */ +typedef struct { + unsigned int windowLog; + unsigned int chainLog; + unsigned int hashLog; + unsigned int searchLog; + unsigned int searchLength; + unsigned int targetLength; + ZSTD_strategy strategy; +} ZSTD_compressionParameters; + +/** + * struct ZSTD_frameParameters - zstd frame parameters + * @contentSizeFlag: Controls whether content size will be present in the frame + * header (when known). + * @checksumFlag: Controls whether a 32-bit checksum is generated at the end + * of the frame for error detection. + * @noDictIDFlag: Controls whether dictID will be saved into the frame header + * when using dictionary compression. + * + * The default value is all fields set to 0. + */ +typedef struct { + unsigned int contentSizeFlag; + unsigned int checksumFlag; + unsigned int noDictIDFlag; +} ZSTD_frameParameters; + +/** + * struct ZSTD_parameters - zstd parameters + * @cParams: The compression parameters. + * @fParams: The frame parameters. + */ +typedef struct { + ZSTD_compressionParameters cParams; + ZSTD_frameParameters fParams; +} ZSTD_parameters; + +/** + * ZSTD_getCParams() - returns ZSTD_compressionParameters for selected level + * @compressionLevel: The compression level from 1 to ZSTD_maxCLevel(). + * @estimatedSrcSize: The estimated source size to compress or 0 if unknown. + * @dictSize: The dictionary size or 0 if a dictionary isn't being used. + * + * Return: The selected ZSTD_compressionParameters. + */ +ZSTD_compressionParameters ZSTD_getCParams(int compressionLevel, + unsigned long long estimatedSrcSize, size_t dictSize); + +/** + * ZSTD_getParams() - returns ZSTD_parameters for selected level + * @compressionLevel: The compression level from 1 to ZSTD_maxCLevel(). + * @estimatedSrcSize: The estimated source size to compress or 0 if unknown. + * @dictSize: The dictionary size or 0 if a dictionary isn't being used. + * + * The same as ZSTD_getCParams() except also selects the default frame + * parameters (all zero). + * + * Return: The selected ZSTD_parameters. + */ +ZSTD_parameters ZSTD_getParams(int compressionLevel, + unsigned long long estimatedSrcSize, size_t dictSize); + +/*-************************************* + * Explicit memory management + **************************************/ + +/** + * ZSTD_CCtxWorkspaceBound() - amount of memory needed to initialize a ZSTD_CCtx + * @cParams: The compression parameters to be used for compression. + * + * If multiple compression parameters might be used, the caller must call + * ZSTD_CCtxWorkspaceBound() for each set of parameters and use the maximum + * size. + * + * Return: A lower bound on the size of the workspace that is passed to + * ZSTD_initCCtx(). + */ +size_t ZSTD_CCtxWorkspaceBound(ZSTD_compressionParameters cParams); + +/** + * struct ZSTD_CCtx - the zstd compression context + * + * When compressing many times it is recommended to allocate a context just once + * and reuse it for each successive compression operation. + */ +typedef struct ZSTD_CCtx_s ZSTD_CCtx; +/** + * ZSTD_initCCtx() - initialize a zstd compression context + * @workspace: The workspace to emplace the context into. It must outlive + * the returned context. + * @workspaceSize: The size of workspace. Use ZSTD_CCtxWorkspaceBound() to + * determine how large the workspace must be. + * + * Return: A compression context emplaced into workspace. + */ +ZSTD_CCtx *ZSTD_initCCtx(void *workspace, size_t workspaceSize); + +/** + * ZSTD_compressCCtx() - compress src into dst + * @ctx: The context. Must have been initialized with a workspace at + * least as large as ZSTD_CCtxWorkspaceBound(params.cParams). + * @dst: The buffer to compress src into. + * @dstCapacity: The size of the destination buffer. May be any size, but + * ZSTD_compressBound(srcSize) is guaranteed to be large enough. + * @src: The data to compress. + * @srcSize: The size of the data to compress. + * @params: The parameters to use for compression. See ZSTD_getParams(). + * + * Return: The compressed size or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_compressCCtx(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize, ZSTD_parameters params); + +/** + * ZSTD_DCtxWorkspaceBound() - amount of memory needed to initialize a ZSTD_DCtx + * + * Return: A lower bound on the size of the workspace that is passed to + * ZSTD_initDCtx(). + */ +size_t ZSTD_DCtxWorkspaceBound(void); + +/** + * struct ZSTD_DCtx - the zstd decompression context + * + * When decompressing many times it is recommended to allocate a context just + * once and reuse it for each successive decompression operation. + */ +typedef struct ZSTD_DCtx_s ZSTD_DCtx; +/** + * ZSTD_initDCtx() - initialize a zstd decompression context + * @workspace: The workspace to emplace the context into. It must outlive + * the returned context. + * @workspaceSize: The size of workspace. Use ZSTD_DCtxWorkspaceBound() to + * determine how large the workspace must be. + * + * Return: A decompression context emplaced into workspace. + */ +ZSTD_DCtx *ZSTD_initDCtx(void *workspace, size_t workspaceSize); + +/** + * ZSTD_decompressDCtx() - decompress zstd compressed src into dst + * @ctx: The decompression context. + * @dst: The buffer to decompress src into. + * @dstCapacity: The size of the destination buffer. Must be at least as large + * as the decompressed size. If the caller cannot upper bound the + * decompressed size, then it's better to use the streaming API. + * @src: The zstd compressed data to decompress. Multiple concatenated + * frames and skippable frames are allowed. + * @srcSize: The exact size of the data to decompress. + * + * Return: The decompressed size or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_decompressDCtx(ZSTD_DCtx *ctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize); + +/*-************************ + * Simple dictionary API + **************************/ + +/** + * ZSTD_compress_usingDict() - compress src into dst using a dictionary + * @ctx: The context. Must have been initialized with a workspace at + * least as large as ZSTD_CCtxWorkspaceBound(params.cParams). + * @dst: The buffer to compress src into. + * @dstCapacity: The size of the destination buffer. May be any size, but + * ZSTD_compressBound(srcSize) is guaranteed to be large enough. + * @src: The data to compress. + * @srcSize: The size of the data to compress. + * @dict: The dictionary to use for compression. + * @dictSize: The size of the dictionary. + * @params: The parameters to use for compression. See ZSTD_getParams(). + * + * Compression using a predefined dictionary. The same dictionary must be used + * during decompression. + * + * Return: The compressed size or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_compress_usingDict(ZSTD_CCtx *ctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize, const void *dict, size_t dictSize, + ZSTD_parameters params); + +/** + * ZSTD_decompress_usingDict() - decompress src into dst using a dictionary + * @ctx: The decompression context. + * @dst: The buffer to decompress src into. + * @dstCapacity: The size of the destination buffer. Must be at least as large + * as the decompressed size. If the caller cannot upper bound the + * decompressed size, then it's better to use the streaming API. + * @src: The zstd compressed data to decompress. Multiple concatenated + * frames and skippable frames are allowed. + * @srcSize: The exact size of the data to decompress. + * @dict: The dictionary to use for decompression. The same dictionary + * must've been used to compress the data. + * @dictSize: The size of the dictionary. + * + * Return: The decompressed size or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_decompress_usingDict(ZSTD_DCtx *ctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize, const void *dict, size_t dictSize); + +/*-************************** + * Fast dictionary API + ***************************/ + +/** + * ZSTD_CDictWorkspaceBound() - memory needed to initialize a ZSTD_CDict + * @cParams: The compression parameters to be used for compression. + * + * Return: A lower bound on the size of the workspace that is passed to + * ZSTD_initCDict(). + */ +size_t ZSTD_CDictWorkspaceBound(ZSTD_compressionParameters cParams); + +/** + * struct ZSTD_CDict - a digested dictionary to be used for compression + */ +typedef struct ZSTD_CDict_s ZSTD_CDict; + +/** + * ZSTD_initCDict() - initialize a digested dictionary for compression + * @dictBuffer: The dictionary to digest. The buffer is referenced by the + * ZSTD_CDict so it must outlive the returned ZSTD_CDict. + * @dictSize: The size of the dictionary. + * @params: The parameters to use for compression. See ZSTD_getParams(). + * @workspace: The workspace. It must outlive the returned ZSTD_CDict. + * @workspaceSize: The workspace size. Must be at least + * ZSTD_CDictWorkspaceBound(params.cParams). + * + * When compressing multiple messages / blocks with the same dictionary it is + * recommended to load it just once. The ZSTD_CDict merely references the + * dictBuffer, so it must outlive the returned ZSTD_CDict. + * + * Return: The digested dictionary emplaced into workspace. + */ +ZSTD_CDict *ZSTD_initCDict(const void *dictBuffer, size_t dictSize, + ZSTD_parameters params, void *workspace, size_t workspaceSize); + +/** + * ZSTD_compress_usingCDict() - compress src into dst using a ZSTD_CDict + * @ctx: The context. Must have been initialized with a workspace at + * least as large as ZSTD_CCtxWorkspaceBound(cParams) where + * cParams are the compression parameters used to initialize the + * cdict. + * @dst: The buffer to compress src into. + * @dstCapacity: The size of the destination buffer. May be any size, but + * ZSTD_compressBound(srcSize) is guaranteed to be large enough. + * @src: The data to compress. + * @srcSize: The size of the data to compress. + * @cdict: The digested dictionary to use for compression. + * @params: The parameters to use for compression. See ZSTD_getParams(). + * + * Compression using a digested dictionary. The same dictionary must be used + * during decompression. + * + * Return: The compressed size or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_compress_usingCDict(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize, const ZSTD_CDict *cdict); + + +/** + * ZSTD_DDictWorkspaceBound() - memory needed to initialize a ZSTD_DDict + * + * Return: A lower bound on the size of the workspace that is passed to + * ZSTD_initDDict(). + */ +size_t ZSTD_DDictWorkspaceBound(void); + +/** + * struct ZSTD_DDict - a digested dictionary to be used for decompression + */ +typedef struct ZSTD_DDict_s ZSTD_DDict; + +/** + * ZSTD_initDDict() - initialize a digested dictionary for decompression + * @dictBuffer: The dictionary to digest. The buffer is referenced by the + * ZSTD_DDict so it must outlive the returned ZSTD_DDict. + * @dictSize: The size of the dictionary. + * @workspace: The workspace. It must outlive the returned ZSTD_DDict. + * @workspaceSize: The workspace size. Must be at least + * ZSTD_DDictWorkspaceBound(). + * + * When decompressing multiple messages / blocks with the same dictionary it is + * recommended to load it just once. The ZSTD_DDict merely references the + * dictBuffer, so it must outlive the returned ZSTD_DDict. + * + * Return: The digested dictionary emplaced into workspace. + */ +ZSTD_DDict *ZSTD_initDDict(const void *dictBuffer, size_t dictSize, + void *workspace, size_t workspaceSize); + +/** + * ZSTD_decompress_usingDDict() - decompress src into dst using a ZSTD_DDict + * @ctx: The decompression context. + * @dst: The buffer to decompress src into. + * @dstCapacity: The size of the destination buffer. Must be at least as large + * as the decompressed size. If the caller cannot upper bound the + * decompressed size, then it's better to use the streaming API. + * @src: The zstd compressed data to decompress. Multiple concatenated + * frames and skippable frames are allowed. + * @srcSize: The exact size of the data to decompress. + * @ddict: The digested dictionary to use for decompression. The same + * dictionary must've been used to compress the data. + * + * Return: The decompressed size or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_decompress_usingDDict(ZSTD_DCtx *dctx, void *dst, + size_t dstCapacity, const void *src, size_t srcSize, + const ZSTD_DDict *ddict); + + +/*-************************** + * Streaming + ***************************/ + +/** + * struct ZSTD_inBuffer - input buffer for streaming + * @src: Start of the input buffer. + * @size: Size of the input buffer. + * @pos: Position where reading stopped. Will be updated. + * Necessarily 0 <= pos <= size. + */ +typedef struct ZSTD_inBuffer_s { + const void *src; + size_t size; + size_t pos; +} ZSTD_inBuffer; + +/** + * struct ZSTD_outBuffer - output buffer for streaming + * @dst: Start of the output buffer. + * @size: Size of the output buffer. + * @pos: Position where writing stopped. Will be updated. + * Necessarily 0 <= pos <= size. + */ +typedef struct ZSTD_outBuffer_s { + void *dst; + size_t size; + size_t pos; +} ZSTD_outBuffer; + + + +/*-***************************************************************************** + * Streaming compression - HowTo + * + * A ZSTD_CStream object is required to track streaming operation. + * Use ZSTD_initCStream() to initialize a ZSTD_CStream object. + * ZSTD_CStream objects can be reused multiple times on consecutive compression + * operations. It is recommended to re-use ZSTD_CStream in situations where many + * streaming operations will be achieved consecutively. Use one separate + * ZSTD_CStream per thread for parallel execution. + * + * Use ZSTD_compressStream() repetitively to consume input stream. + * The function will automatically update both `pos` fields. + * Note that it may not consume the entire input, in which case `pos < size`, + * and it's up to the caller to present again remaining data. + * It returns a hint for the preferred number of bytes to use as an input for + * the next function call. + * + * At any moment, it's possible to flush whatever data remains within internal + * buffer, using ZSTD_flushStream(). `output->pos` will be updated. There might + * still be some content left within the internal buffer if `output->size` is + * too small. It returns the number of bytes left in the internal buffer and + * must be called until it returns 0. + * + * ZSTD_endStream() instructs to finish a frame. It will perform a flush and + * write frame epilogue. The epilogue is required for decoders to consider a + * frame completed. Similar to ZSTD_flushStream(), it may not be able to flush + * the full content if `output->size` is too small. In which case, call again + * ZSTD_endStream() to complete the flush. It returns the number of bytes left + * in the internal buffer and must be called until it returns 0. + ******************************************************************************/ + +/** + * ZSTD_CStreamWorkspaceBound() - memory needed to initialize a ZSTD_CStream + * @cParams: The compression parameters to be used for compression. + * + * Return: A lower bound on the size of the workspace that is passed to + * ZSTD_initCStream() and ZSTD_initCStream_usingCDict(). + */ +size_t ZSTD_CStreamWorkspaceBound(ZSTD_compressionParameters cParams); + +/** + * struct ZSTD_CStream - the zstd streaming compression context + */ +typedef struct ZSTD_CStream_s ZSTD_CStream; + +/*===== ZSTD_CStream management functions =====*/ +/** + * ZSTD_initCStream() - initialize a zstd streaming compression context + * @params: The zstd compression parameters. + * @pledgedSrcSize: If params.fParams.contentSizeFlag == 1 then the caller must + * pass the source size (zero means empty source). Otherwise, + * the caller may optionally pass the source size, or zero if + * unknown. + * @workspace: The workspace to emplace the context into. It must outlive + * the returned context. + * @workspaceSize: The size of workspace. + * Use ZSTD_CStreamWorkspaceBound(params.cParams) to determine + * how large the workspace must be. + * + * Return: The zstd streaming compression context. + */ +ZSTD_CStream *ZSTD_initCStream(ZSTD_parameters params, + unsigned long long pledgedSrcSize, void *workspace, + size_t workspaceSize); + +/** + * ZSTD_initCStream_usingCDict() - initialize a streaming compression context + * @cdict: The digested dictionary to use for compression. + * @pledgedSrcSize: Optionally the source size, or zero if unknown. + * @workspace: The workspace to emplace the context into. It must outlive + * the returned context. + * @workspaceSize: The size of workspace. Call ZSTD_CStreamWorkspaceBound() + * with the cParams used to initialize the cdict to determine + * how large the workspace must be. + * + * Return: The zstd streaming compression context. + */ +ZSTD_CStream *ZSTD_initCStream_usingCDict(const ZSTD_CDict *cdict, + unsigned long long pledgedSrcSize, void *workspace, + size_t workspaceSize); + +/*===== Streaming compression functions =====*/ +/** + * ZSTD_resetCStream() - reset the context using parameters from creation + * @zcs: The zstd streaming compression context to reset. + * @pledgedSrcSize: Optionally the source size, or zero if unknown. + * + * Resets the context using the parameters from creation. Skips dictionary + * loading, since it can be reused. If `pledgedSrcSize` is non-zero the frame + * content size is always written into the frame header. + * + * Return: Zero or an error, which can be checked using ZSTD_isError(). + */ +size_t ZSTD_resetCStream(ZSTD_CStream *zcs, unsigned long long pledgedSrcSize); +/** + * ZSTD_compressStream() - streaming compress some of input into output + * @zcs: The zstd streaming compression context. + * @output: Destination buffer. `output->pos` is updated to indicate how much + * compressed data was written. + * @input: Source buffer. `input->pos` is updated to indicate how much data was + * read. Note that it may not consume the entire input, in which case + * `input->pos < input->size`, and it's up to the caller to present + * remaining data again. + * + * The `input` and `output` buffers may be any size. Guaranteed to make some + * forward progress if `input` and `output` are not empty. + * + * Return: A hint for the number of bytes to use as the input for the next + * function call or an error, which can be checked using + * ZSTD_isError(). + */ +size_t ZSTD_compressStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output, + ZSTD_inBuffer *input); +/** + * ZSTD_flushStream() - flush internal buffers into output + * @zcs: The zstd streaming compression context. + * @output: Destination buffer. `output->pos` is updated to indicate how much + * compressed data was written. + * + * ZSTD_flushStream() must be called until it returns 0, meaning all the data + * has been flushed. Since ZSTD_flushStream() causes a block to be ended, + * calling it too often will degrade the compression ratio. + * + * Return: The number of bytes still present within internal buffers or an + * error, which can be checked using ZSTD_isError(). + */ +size_t ZSTD_flushStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output); +/** + * ZSTD_endStream() - flush internal buffers into output and end the frame + * @zcs: The zstd streaming compression context. + * @output: Destination buffer. `output->pos` is updated to indicate how much + * compressed data was written. + * + * ZSTD_endStream() must be called until it returns 0, meaning all the data has + * been flushed and the frame epilogue has been written. + * + * Return: The number of bytes still present within internal buffers or an + * error, which can be checked using ZSTD_isError(). + */ +size_t ZSTD_endStream(ZSTD_CStream *zcs, ZSTD_outBuffer *output); + +/** + * ZSTD_CStreamInSize() - recommended size for the input buffer + * + * Return: The recommended size for the input buffer. + */ +size_t ZSTD_CStreamInSize(void); +/** + * ZSTD_CStreamOutSize() - recommended size for the output buffer + * + * When the output buffer is at least this large, it is guaranteed to be large + * enough to flush at least one complete compressed block. + * + * Return: The recommended size for the output buffer. + */ +size_t ZSTD_CStreamOutSize(void); + + + +/*-***************************************************************************** + * Streaming decompression - HowTo + * + * A ZSTD_DStream object is required to track streaming operations. + * Use ZSTD_initDStream() to initialize a ZSTD_DStream object. + * ZSTD_DStream objects can be re-used multiple times. + * + * Use ZSTD_decompressStream() repetitively to consume your input. + * The function will update both `pos` fields. + * If `input->pos < input->size`, some input has not been consumed. + * It's up to the caller to present again remaining data. + * If `output->pos < output->size`, decoder has flushed everything it could. + * Returns 0 iff a frame is completely decoded and fully flushed. + * Otherwise it returns a suggested next input size that will never load more + * than the current frame. + ******************************************************************************/ + +/** + * ZSTD_DStreamWorkspaceBound() - memory needed to initialize a ZSTD_DStream + * @maxWindowSize: The maximum window size allowed for compressed frames. + * + * Return: A lower bound on the size of the workspace that is passed to + * ZSTD_initDStream() and ZSTD_initDStream_usingDDict(). + */ +size_t ZSTD_DStreamWorkspaceBound(size_t maxWindowSize); + +/** + * struct ZSTD_DStream - the zstd streaming decompression context + */ +typedef struct ZSTD_DStream_s ZSTD_DStream; +/*===== ZSTD_DStream management functions =====*/ +/** + * ZSTD_initDStream() - initialize a zstd streaming decompression context + * @maxWindowSize: The maximum window size allowed for compressed frames. + * @workspace: The workspace to emplace the context into. It must outlive + * the returned context. + * @workspaceSize: The size of workspace. + * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine + * how large the workspace must be. + * + * Return: The zstd streaming decompression context. + */ +ZSTD_DStream *ZSTD_initDStream(size_t maxWindowSize, void *workspace, + size_t workspaceSize); +/** + * ZSTD_initDStream_usingDDict() - initialize streaming decompression context + * @maxWindowSize: The maximum window size allowed for compressed frames. + * @ddict: The digested dictionary to use for decompression. + * @workspace: The workspace to emplace the context into. It must outlive + * the returned context. + * @workspaceSize: The size of workspace. + * Use ZSTD_DStreamWorkspaceBound(maxWindowSize) to determine + * how large the workspace must be. + * + * Return: The zstd streaming decompression context. + */ +ZSTD_DStream *ZSTD_initDStream_usingDDict(size_t maxWindowSize, + const ZSTD_DDict *ddict, void *workspace, size_t workspaceSize); + +/*===== Streaming decompression functions =====*/ +/** + * ZSTD_resetDStream() - reset the context using parameters from creation + * @zds: The zstd streaming decompression context to reset. + * + * Resets the context using the parameters from creation. Skips dictionary + * loading, since it can be reused. + * + * Return: Zero or an error, which can be checked using ZSTD_isError(). + */ +size_t ZSTD_resetDStream(ZSTD_DStream *zds); +/** + * ZSTD_decompressStream() - streaming decompress some of input into output + * @zds: The zstd streaming decompression context. + * @output: Destination buffer. `output.pos` is updated to indicate how much + * decompressed data was written. + * @input: Source buffer. `input.pos` is updated to indicate how much data was + * read. Note that it may not consume the entire input, in which case + * `input.pos < input.size`, and it's up to the caller to present + * remaining data again. + * + * The `input` and `output` buffers may be any size. Guaranteed to make some + * forward progress if `input` and `output` are not empty. + * ZSTD_decompressStream() will not consume the last byte of the frame until + * the entire frame is flushed. + * + * Return: Returns 0 iff a frame is completely decoded and fully flushed. + * Otherwise returns a hint for the number of bytes to use as the input + * for the next function call or an error, which can be checked using + * ZSTD_isError(). The size hint will never load more than the frame. + */ +size_t ZSTD_decompressStream(ZSTD_DStream *zds, ZSTD_outBuffer *output, + ZSTD_inBuffer *input); + +/** + * ZSTD_DStreamInSize() - recommended size for the input buffer + * + * Return: The recommended size for the input buffer. + */ +size_t ZSTD_DStreamInSize(void); +/** + * ZSTD_DStreamOutSize() - recommended size for the output buffer + * + * When the output buffer is at least this large, it is guaranteed to be large + * enough to flush at least one complete decompressed block. + * + * Return: The recommended size for the output buffer. + */ +size_t ZSTD_DStreamOutSize(void); + + +/* --- Constants ---*/ +#define ZSTD_MAGICNUMBER 0xFD2FB528 /* >= v0.8.0 */ +#define ZSTD_MAGIC_SKIPPABLE_START 0x184D2A50U + +#define ZSTD_CONTENTSIZE_UNKNOWN (0ULL - 1) +#define ZSTD_CONTENTSIZE_ERROR (0ULL - 2) + +#define ZSTD_WINDOWLOG_MAX_32 27 +#define ZSTD_WINDOWLOG_MAX_64 27 +#define ZSTD_WINDOWLOG_MAX \ + ((unsigned int)(sizeof(size_t) == 4 \ + ? ZSTD_WINDOWLOG_MAX_32 \ + : ZSTD_WINDOWLOG_MAX_64)) +#define ZSTD_WINDOWLOG_MIN 10 +#define ZSTD_HASHLOG_MAX ZSTD_WINDOWLOG_MAX +#define ZSTD_HASHLOG_MIN 6 +#define ZSTD_CHAINLOG_MAX (ZSTD_WINDOWLOG_MAX+1) +#define ZSTD_CHAINLOG_MIN ZSTD_HASHLOG_MIN +#define ZSTD_HASHLOG3_MAX 17 +#define ZSTD_SEARCHLOG_MAX (ZSTD_WINDOWLOG_MAX-1) +#define ZSTD_SEARCHLOG_MIN 1 +/* only for ZSTD_fast, other strategies are limited to 6 */ +#define ZSTD_SEARCHLENGTH_MAX 7 +/* only for ZSTD_btopt, other strategies are limited to 4 */ +#define ZSTD_SEARCHLENGTH_MIN 3 +#define ZSTD_TARGETLENGTH_MIN 4 +#define ZSTD_TARGETLENGTH_MAX 999 + +/* for static allocation */ +#define ZSTD_FRAMEHEADERSIZE_MAX 18 +#define ZSTD_FRAMEHEADERSIZE_MIN 6 +static const size_t ZSTD_frameHeaderSize_prefix = 5; +static const size_t ZSTD_frameHeaderSize_min = ZSTD_FRAMEHEADERSIZE_MIN; +static const size_t ZSTD_frameHeaderSize_max = ZSTD_FRAMEHEADERSIZE_MAX; +/* magic number + skippable frame length */ +static const size_t ZSTD_skippableHeaderSize = 8; + + +/*-************************************* + * Compressed size functions + **************************************/ + +/** + * ZSTD_findFrameCompressedSize() - returns the size of a compressed frame + * @src: Source buffer. It should point to the start of a zstd encoded frame + * or a skippable frame. + * @srcSize: The size of the source buffer. It must be at least as large as the + * size of the frame. + * + * Return: The compressed size of the frame pointed to by `src` or an error, + * which can be check with ZSTD_isError(). + * Suitable to pass to ZSTD_decompress() or similar functions. + */ +size_t ZSTD_findFrameCompressedSize(const void *src, size_t srcSize); + +/*-************************************* + * Decompressed size functions + **************************************/ +/** + * ZSTD_getFrameContentSize() - returns the content size in a zstd frame header + * @src: It should point to the start of a zstd encoded frame. + * @srcSize: The size of the source buffer. It must be at least as large as the + * frame header. `ZSTD_frameHeaderSize_max` is always large enough. + * + * Return: The frame content size stored in the frame header if known. + * `ZSTD_CONTENTSIZE_UNKNOWN` if the content size isn't stored in the + * frame header. `ZSTD_CONTENTSIZE_ERROR` on invalid input. + */ +unsigned long long ZSTD_getFrameContentSize(const void *src, size_t srcSize); + +/** + * ZSTD_findDecompressedSize() - returns decompressed size of a series of frames + * @src: It should point to the start of a series of zstd encoded and/or + * skippable frames. + * @srcSize: The exact size of the series of frames. + * + * If any zstd encoded frame in the series doesn't have the frame content size + * set, `ZSTD_CONTENTSIZE_UNKNOWN` is returned. But frame content size is always + * set when using ZSTD_compress(). The decompressed size can be very large. + * If the source is untrusted, the decompressed size could be wrong or + * intentionally modified. Always ensure the result fits within the + * application's authorized limits. ZSTD_findDecompressedSize() handles multiple + * frames, and so it must traverse the input to read each frame header. This is + * efficient as most of the data is skipped, however it does mean that all frame + * data must be present and valid. + * + * Return: Decompressed size of all the data contained in the frames if known. + * `ZSTD_CONTENTSIZE_UNKNOWN` if the decompressed size is unknown. + * `ZSTD_CONTENTSIZE_ERROR` if an error occurred. + */ +unsigned long long ZSTD_findDecompressedSize(const void *src, size_t srcSize); + +/*-************************************* + * Advanced compression functions + **************************************/ +/** + * ZSTD_checkCParams() - ensure parameter values remain within authorized range + * @cParams: The zstd compression parameters. + * + * Return: Zero or an error, which can be checked using ZSTD_isError(). + */ +size_t ZSTD_checkCParams(ZSTD_compressionParameters cParams); + +/** + * ZSTD_adjustCParams() - optimize parameters for a given srcSize and dictSize + * @srcSize: Optionally the estimated source size, or zero if unknown. + * @dictSize: Optionally the estimated dictionary size, or zero if unknown. + * + * Return: The optimized parameters. + */ +ZSTD_compressionParameters ZSTD_adjustCParams( + ZSTD_compressionParameters cParams, unsigned long long srcSize, + size_t dictSize); + +/*--- Advanced decompression functions ---*/ + +/** + * ZSTD_isFrame() - returns true iff the buffer starts with a valid frame + * @buffer: The source buffer to check. + * @size: The size of the source buffer, must be at least 4 bytes. + * + * Return: True iff the buffer starts with a zstd or skippable frame identifier. + */ +unsigned int ZSTD_isFrame(const void *buffer, size_t size); + +/** + * ZSTD_getDictID_fromDict() - returns the dictionary id stored in a dictionary + * @dict: The dictionary buffer. + * @dictSize: The size of the dictionary buffer. + * + * Return: The dictionary id stored within the dictionary or 0 if the + * dictionary is not a zstd dictionary. If it returns 0 the + * dictionary can still be loaded as a content-only dictionary. + */ +unsigned int ZSTD_getDictID_fromDict(const void *dict, size_t dictSize); + +/** + * ZSTD_getDictID_fromDDict() - returns the dictionary id stored in a ZSTD_DDict + * @ddict: The ddict to find the id of. + * + * Return: The dictionary id stored within `ddict` or 0 if the dictionary is not + * a zstd dictionary. If it returns 0 `ddict` will be loaded as a + * content-only dictionary. + */ +unsigned int ZSTD_getDictID_fromDDict(const ZSTD_DDict *ddict); + +/** + * ZSTD_getDictID_fromFrame() - returns the dictionary id stored in a zstd frame + * @src: Source buffer. It must be a zstd encoded frame. + * @srcSize: The size of the source buffer. It must be at least as large as the + * frame header. `ZSTD_frameHeaderSize_max` is always large enough. + * + * Return: The dictionary id required to decompress the frame stored within + * `src` or 0 if the dictionary id could not be decoded. It can return + * 0 if the frame does not require a dictionary, the dictionary id + * wasn't stored in the frame, `src` is not a zstd frame, or `srcSize` + * is too small. + */ +unsigned int ZSTD_getDictID_fromFrame(const void *src, size_t srcSize); + +/** + * struct ZSTD_frameParams - zstd frame parameters stored in the frame header + * @frameContentSize: The frame content size, or 0 if not present. + * @windowSize: The window size, or 0 if the frame is a skippable frame. + * @dictID: The dictionary id, or 0 if not present. + * @checksumFlag: Whether a checksum was used. + */ +typedef struct { + unsigned long long frameContentSize; + unsigned int windowSize; + unsigned int dictID; + unsigned int checksumFlag; +} ZSTD_frameParams; + +/** + * ZSTD_getFrameParams() - extracts parameters from a zstd or skippable frame + * @fparamsPtr: On success the frame parameters are written here. + * @src: The source buffer. It must point to a zstd or skippable frame. + * @srcSize: The size of the source buffer. `ZSTD_frameHeaderSize_max` is + * always large enough to succeed. + * + * Return: 0 on success. If more data is required it returns how many bytes + * must be provided to make forward progress. Otherwise it returns + * an error, which can be checked using ZSTD_isError(). + */ +size_t ZSTD_getFrameParams(ZSTD_frameParams *fparamsPtr, const void *src, + size_t srcSize); + +/*-***************************************************************************** + * Buffer-less and synchronous inner streaming functions + * + * This is an advanced API, giving full control over buffer management, for + * users which need direct control over memory. + * But it's also a complex one, with many restrictions (documented below). + * Prefer using normal streaming API for an easier experience + ******************************************************************************/ + +/*-***************************************************************************** + * Buffer-less streaming compression (synchronous mode) + * + * A ZSTD_CCtx object is required to track streaming operations. + * Use ZSTD_initCCtx() to initialize a context. + * ZSTD_CCtx object can be re-used multiple times within successive compression + * operations. + * + * Start by initializing a context. + * Use ZSTD_compressBegin(), or ZSTD_compressBegin_usingDict() for dictionary + * compression, + * or ZSTD_compressBegin_advanced(), for finer parameter control. + * It's also possible to duplicate a reference context which has already been + * initialized, using ZSTD_copyCCtx() + * + * Then, consume your input using ZSTD_compressContinue(). + * There are some important considerations to keep in mind when using this + * advanced function : + * - ZSTD_compressContinue() has no internal buffer. It uses externally provided + * buffer only. + * - Interface is synchronous : input is consumed entirely and produce 1+ + * (or more) compressed blocks. + * - Caller must ensure there is enough space in `dst` to store compressed data + * under worst case scenario. Worst case evaluation is provided by + * ZSTD_compressBound(). + * ZSTD_compressContinue() doesn't guarantee recover after a failed + * compression. + * - ZSTD_compressContinue() presumes prior input ***is still accessible and + * unmodified*** (up to maximum distance size, see WindowLog). + * It remembers all previous contiguous blocks, plus one separated memory + * segment (which can itself consists of multiple contiguous blocks) + * - ZSTD_compressContinue() detects that prior input has been overwritten when + * `src` buffer overlaps. In which case, it will "discard" the relevant memory + * section from its history. + * + * Finish a frame with ZSTD_compressEnd(), which will write the last block(s) + * and optional checksum. It's possible to use srcSize==0, in which case, it + * will write a final empty block to end the frame. Without last block mark, + * frames will be considered unfinished (corrupted) by decoders. + * + * `ZSTD_CCtx` object can be re-used (ZSTD_compressBegin()) to compress some new + * frame. + ******************************************************************************/ + +/*===== Buffer-less streaming compression functions =====*/ +size_t ZSTD_compressBegin(ZSTD_CCtx *cctx, int compressionLevel); +size_t ZSTD_compressBegin_usingDict(ZSTD_CCtx *cctx, const void *dict, + size_t dictSize, int compressionLevel); +size_t ZSTD_compressBegin_advanced(ZSTD_CCtx *cctx, const void *dict, + size_t dictSize, ZSTD_parameters params, + unsigned long long pledgedSrcSize); +size_t ZSTD_copyCCtx(ZSTD_CCtx *cctx, const ZSTD_CCtx *preparedCCtx, + unsigned long long pledgedSrcSize); +size_t ZSTD_compressBegin_usingCDict(ZSTD_CCtx *cctx, const ZSTD_CDict *cdict, + unsigned long long pledgedSrcSize); +size_t ZSTD_compressContinue(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize); +size_t ZSTD_compressEnd(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize); + + + +/*-***************************************************************************** + * Buffer-less streaming decompression (synchronous mode) + * + * A ZSTD_DCtx object is required to track streaming operations. + * Use ZSTD_initDCtx() to initialize a context. + * A ZSTD_DCtx object can be re-used multiple times. + * + * First typical operation is to retrieve frame parameters, using + * ZSTD_getFrameParams(). It fills a ZSTD_frameParams structure which provide + * important information to correctly decode the frame, such as the minimum + * rolling buffer size to allocate to decompress data (`windowSize`), and the + * dictionary ID used. + * Note: content size is optional, it may not be present. 0 means unknown. + * Note that these values could be wrong, either because of data malformation, + * or because an attacker is spoofing deliberate false information. As a + * consequence, check that values remain within valid application range, + * especially `windowSize`, before allocation. Each application can set its own + * limit, depending on local restrictions. For extended interoperability, it is + * recommended to support at least 8 MB. + * Frame parameters are extracted from the beginning of the compressed frame. + * Data fragment must be large enough to ensure successful decoding, typically + * `ZSTD_frameHeaderSize_max` bytes. + * Result: 0: successful decoding, the `ZSTD_frameParams` structure is filled. + * >0: `srcSize` is too small, provide at least this many bytes. + * errorCode, which can be tested using ZSTD_isError(). + * + * Start decompression, with ZSTD_decompressBegin() or + * ZSTD_decompressBegin_usingDict(). Alternatively, you can copy a prepared + * context, using ZSTD_copyDCtx(). + * + * Then use ZSTD_nextSrcSizeToDecompress() and ZSTD_decompressContinue() + * alternatively. + * ZSTD_nextSrcSizeToDecompress() tells how many bytes to provide as 'srcSize' + * to ZSTD_decompressContinue(). + * ZSTD_decompressContinue() requires this _exact_ amount of bytes, or it will + * fail. + * + * The result of ZSTD_decompressContinue() is the number of bytes regenerated + * within 'dst' (necessarily <= dstCapacity). It can be zero, which is not an + * error; it just means ZSTD_decompressContinue() has decoded some metadata + * item. It can also be an error code, which can be tested with ZSTD_isError(). + * + * ZSTD_decompressContinue() needs previous data blocks during decompression, up + * to `windowSize`. They should preferably be located contiguously, prior to + * current block. Alternatively, a round buffer of sufficient size is also + * possible. Sufficient size is determined by frame parameters. + * ZSTD_decompressContinue() is very sensitive to contiguity, if 2 blocks don't + * follow each other, make sure that either the compressor breaks contiguity at + * the same place, or that previous contiguous segment is large enough to + * properly handle maximum back-reference. + * + * A frame is fully decoded when ZSTD_nextSrcSizeToDecompress() returns zero. + * Context can then be reset to start a new decompression. + * + * Note: it's possible to know if next input to present is a header or a block, + * using ZSTD_nextInputType(). This information is not required to properly + * decode a frame. + * + * == Special case: skippable frames == + * + * Skippable frames allow integration of user-defined data into a flow of + * concatenated frames. Skippable frames will be ignored (skipped) by a + * decompressor. The format of skippable frames is as follows: + * a) Skippable frame ID - 4 Bytes, Little endian format, any value from + * 0x184D2A50 to 0x184D2A5F + * b) Frame Size - 4 Bytes, Little endian format, unsigned 32-bits + * c) Frame Content - any content (User Data) of length equal to Frame Size + * For skippable frames ZSTD_decompressContinue() always returns 0. + * For skippable frames ZSTD_getFrameParams() returns fparamsPtr->windowLog==0 + * what means that a frame is skippable. + * Note: If fparamsPtr->frameContentSize==0, it is ambiguous: the frame might + * actually be a zstd encoded frame with no content. For purposes of + * decompression, it is valid in both cases to skip the frame using + * ZSTD_findFrameCompressedSize() to find its size in bytes. + * It also returns frame size as fparamsPtr->frameContentSize. + ******************************************************************************/ + +/*===== Buffer-less streaming decompression functions =====*/ +size_t ZSTD_decompressBegin(ZSTD_DCtx *dctx); +size_t ZSTD_decompressBegin_usingDict(ZSTD_DCtx *dctx, const void *dict, + size_t dictSize); +void ZSTD_copyDCtx(ZSTD_DCtx *dctx, const ZSTD_DCtx *preparedDCtx); +size_t ZSTD_nextSrcSizeToDecompress(ZSTD_DCtx *dctx); +size_t ZSTD_decompressContinue(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize); +typedef enum { + ZSTDnit_frameHeader, + ZSTDnit_blockHeader, + ZSTDnit_block, + ZSTDnit_lastBlock, + ZSTDnit_checksum, + ZSTDnit_skippableFrame +} ZSTD_nextInputType_e; +ZSTD_nextInputType_e ZSTD_nextInputType(ZSTD_DCtx *dctx); + +/*-***************************************************************************** + * Block functions + * + * Block functions produce and decode raw zstd blocks, without frame metadata. + * Frame metadata cost is typically ~18 bytes, which can be non-negligible for + * very small blocks (< 100 bytes). User will have to take in charge required + * information to regenerate data, such as compressed and content sizes. + * + * A few rules to respect: + * - Compressing and decompressing require a context structure + * + Use ZSTD_initCCtx() and ZSTD_initDCtx() + * - It is necessary to init context before starting + * + compression : ZSTD_compressBegin() + * + decompression : ZSTD_decompressBegin() + * + variants _usingDict() are also allowed + * + copyCCtx() and copyDCtx() work too + * - Block size is limited, it must be <= ZSTD_getBlockSizeMax() + * + If you need to compress more, cut data into multiple blocks + * + Consider using the regular ZSTD_compress() instead, as frame metadata + * costs become negligible when source size is large. + * - When a block is considered not compressible enough, ZSTD_compressBlock() + * result will be zero. In which case, nothing is produced into `dst`. + * + User must test for such outcome and deal directly with uncompressed data + * + ZSTD_decompressBlock() doesn't accept uncompressed data as input!!! + * + In case of multiple successive blocks, decoder must be informed of + * uncompressed block existence to follow proper history. Use + * ZSTD_insertBlock() in such a case. + ******************************************************************************/ + +/* Define for static allocation */ +#define ZSTD_BLOCKSIZE_ABSOLUTEMAX (128 * 1024) +/*===== Raw zstd block functions =====*/ +size_t ZSTD_getBlockSizeMax(ZSTD_CCtx *cctx); +size_t ZSTD_compressBlock(ZSTD_CCtx *cctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize); +size_t ZSTD_decompressBlock(ZSTD_DCtx *dctx, void *dst, size_t dstCapacity, + const void *src, size_t srcSize); +size_t ZSTD_insertBlock(ZSTD_DCtx *dctx, const void *blockStart, + size_t blockSize); + +#endif /* ZSTD_H */ -- 2.26.2