From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932433AbaESTAK (ORCPT ); Mon, 19 May 2014 15:00:10 -0400 Received: from mail.skyhub.de ([78.46.96.112]:38917 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751389AbaESS7k (ORCPT ); Mon, 19 May 2014 14:59:40 -0400 From: Borislav Petkov To: X86 ML Cc: LKML , Borislav Petkov Subject: [PATCH 1/2] x86: Carve out cmdline parsing function Date: Mon, 19 May 2014 20:59:16 +0200 Message-Id: <1400525957-11525-2-git-send-email-bp@alien8.de> X-Mailer: git-send-email 1.9.0 In-Reply-To: <1400525957-11525-1-git-send-email-bp@alien8.de> References: <1400525957-11525-1-git-send-email-bp@alien8.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Borislav Petkov into .../lib/cmdline.c to use by kernel proper too. Adapted from arch/x86/boot/cmdline.c. Signed-off-by: Borislav Petkov --- arch/x86/include/asm/cmdline.h | 6 +++ arch/x86/lib/Makefile | 2 +- arch/x86/lib/cmdline.c | 84 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 91 insertions(+), 1 deletion(-) create mode 100644 arch/x86/include/asm/cmdline.h create mode 100644 arch/x86/lib/cmdline.c diff --git a/arch/x86/include/asm/cmdline.h b/arch/x86/include/asm/cmdline.h new file mode 100644 index 000000000000..e01f7f7ccb0c --- /dev/null +++ b/arch/x86/include/asm/cmdline.h @@ -0,0 +1,6 @@ +#ifndef _ASM_X86_CMDLINE_H +#define _ASM_X86_CMDLINE_H + +int cmdline_find_option_bool(const char *cmdline_ptr, const char *option); + +#endif /* _ASM_X86_CMDLINE_H */ diff --git a/arch/x86/lib/Makefile b/arch/x86/lib/Makefile index eabcb6e6a900..4d4f96a27638 100644 --- a/arch/x86/lib/Makefile +++ b/arch/x86/lib/Makefile @@ -16,7 +16,7 @@ clean-files := inat-tables.c obj-$(CONFIG_SMP) += msr-smp.o cache-smp.o -lib-y := delay.o misc.o +lib-y := delay.o misc.o cmdline.o lib-y += thunk_$(BITS).o lib-y += usercopy_$(BITS).o usercopy.o getuser.o putuser.o lib-y += memcpy_$(BITS).o diff --git a/arch/x86/lib/cmdline.c b/arch/x86/lib/cmdline.c new file mode 100644 index 000000000000..422db000d727 --- /dev/null +++ b/arch/x86/lib/cmdline.c @@ -0,0 +1,84 @@ +/* + * This file is part of the Linux kernel, and is made available under + * the terms of the GNU General Public License version 2. + * + * Misc librarized functions for cmdline poking. + */ +#include +#include +#include +#include + +static inline int myisspace(u8 c) +{ + return c <= ' '; /* Close enough approximation */ +} + +/** + * Find a boolean option (like quiet,noapic,nosmp....) + * + * @cmdline: the cmdline string + * @option: option string to look for + * + * Returns the position of that @option (starts counting with 1) + * or 0 on not found. + */ +int cmdline_find_option_bool(const char *cmdline, const char *option) +{ + char c; + int len, pos = 0, wstart = 0; + const char *opptr = NULL; + enum { + st_wordstart = 0, /* Start of word/after whitespace */ + st_wordcmp, /* Comparing this word */ + st_wordskip, /* Miscompare, skip */ + } state = st_wordstart; + + if (!cmdline) + return -1; /* No command line */ + + len = min_t(int, strlen(cmdline), COMMAND_LINE_SIZE); + if (!len) + return 0; + + while (len--) { + c = *(char *)cmdline++; + pos++; + + switch (state) { + case st_wordstart: + if (!c) + return 0; + else if (myisspace(c)) + break; + + state = st_wordcmp; + opptr = option; + wstart = pos; + /* fall through */ + + case st_wordcmp: + if (!*opptr) + if (!c || myisspace(c)) + return wstart; + else + state = st_wordskip; + else if (!c) + return 0; + else if (c != *opptr++) + state = st_wordskip; + else if (!len) /* last word and is matching */ + return wstart; + break; + + case st_wordskip: + if (!c) + return 0; + else if (myisspace(c)) + state = st_wordstart; + break; + } + } + + return 0; /* Buffer overrun */ +} -- 1.9.0