Re: [Qemu-devel] [PATCH v1 18/22] migration: delete QEMUFile stdio implementation

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Daniel P. Berrange (berrange@redhat.com) wrote:
> Now that the exec migration backend and savevm have converted
> to use the QIOChannel based QEMUFile, there is no user remaining
> for the stdio based QEMUFile impl and it can be deleted.
> 
> Signed-off-by: Daniel P. Berrange <berrange@redhat.com>

Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

> ---
>  include/migration/qemu-file.h |   2 -
>  migration/Makefile.objs       |   2 +-
>  migration/qemu-file-stdio.c   | 195 ------------------------------------------
>  3 files changed, 1 insertion(+), 198 deletions(-)
>  delete mode 100644 migration/qemu-file-stdio.c
> 
> diff --git a/include/migration/qemu-file.h b/include/migration/qemu-file.h
> index dc4b7ab..6a66735 100644
> --- a/include/migration/qemu-file.h
> +++ b/include/migration/qemu-file.h
> @@ -128,10 +128,8 @@ typedef struct QEMUFileHooks {
>  } QEMUFileHooks;
>  
>  QEMUFile *qemu_fopen_ops(void *opaque, const QEMUFileOps *ops);
> -QEMUFile *qemu_fopen(const char *filename, const char *mode);
>  QEMUFile *qemu_fopen_channel_input(QIOChannel *ioc);
>  QEMUFile *qemu_fopen_channel_output(QIOChannel *ioc);
> -QEMUFile *qemu_popen_cmd(const char *command, const char *mode);
>  void qemu_file_set_hooks(QEMUFile *f, const QEMUFileHooks *hooks);
>  int qemu_get_fd(QEMUFile *f);
>  int qemu_fclose(QEMUFile *f);
> diff --git a/migration/Makefile.objs b/migration/Makefile.objs
> index 2c71056..a127f31 100644
> --- a/migration/Makefile.objs
> +++ b/migration/Makefile.objs
> @@ -1,6 +1,6 @@
>  common-obj-y += migration.o tcp.o unix.o fd.o exec.o
>  common-obj-y += vmstate.o
> -common-obj-y += qemu-file.o qemu-file-stdio.o
> +common-obj-y += qemu-file.o
>  common-obj-y += qemu-file-channel.o
>  common-obj-y += xbzrle.o postcopy-ram.o
>  
> diff --git a/migration/qemu-file-stdio.c b/migration/qemu-file-stdio.c
> deleted file mode 100644
> index 9bde9db..0000000
> --- a/migration/qemu-file-stdio.c
> +++ /dev/null
> @@ -1,195 +0,0 @@
> -/*
> - * QEMU System Emulator
> - *
> - * Copyright (c) 2003-2008 Fabrice Bellard
> - *
> - * Permission is hereby granted, free of charge, to any person obtaining a copy
> - * of this software and associated documentation files (the "Software"), to deal
> - * in the Software without restriction, including without limitation the rights
> - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
> - * copies of the Software, and to permit persons to whom the Software is
> - * furnished to do so, subject to the following conditions:
> - *
> - * The above copyright notice and this permission notice shall be included in
> - * all copies or substantial portions of the Software.
> - *
> - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
> - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
> - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
> - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
> - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
> - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
> - * THE SOFTWARE.
> - */
> -#include "qemu-common.h"
> -#include "qemu/coroutine.h"
> -#include "migration/qemu-file.h"
> -
> -typedef struct QEMUFileStdio {
> -    FILE *stdio_file;
> -    QEMUFile *file;
> -} QEMUFileStdio;
> -
> -static int stdio_get_fd(void *opaque)
> -{
> -    QEMUFileStdio *s = opaque;
> -
> -    return fileno(s->stdio_file);
> -}
> -
> -static ssize_t stdio_put_buffer(void *opaque, const uint8_t *buf, int64_t pos,
> -                                size_t size)
> -{
> -    QEMUFileStdio *s = opaque;
> -    size_t res;
> -
> -    res = fwrite(buf, 1, size, s->stdio_file);
> -
> -    if (res != size) {
> -        return -errno;
> -    }
> -    return res;
> -}
> -
> -static ssize_t stdio_get_buffer(void *opaque, uint8_t *buf, int64_t pos,
> -                                size_t size)
> -{
> -    QEMUFileStdio *s = opaque;
> -    FILE *fp = s->stdio_file;
> -    ssize_t bytes;
> -
> -    for (;;) {
> -        clearerr(fp);
> -        bytes = fread(buf, 1, size, fp);
> -        if (bytes != 0 || !ferror(fp)) {
> -            break;
> -        }
> -        if (errno == EAGAIN) {
> -            yield_until_fd_readable(fileno(fp));
> -        } else if (errno != EINTR) {
> -            break;
> -        }
> -    }
> -    return bytes;
> -}
> -
> -static int stdio_pclose(void *opaque)
> -{
> -    QEMUFileStdio *s = opaque;
> -    int ret;
> -    ret = pclose(s->stdio_file);
> -    if (ret == -1) {
> -        ret = -errno;
> -    } else if (!WIFEXITED(ret) || WEXITSTATUS(ret) != 0) {
> -        /* close succeeded, but non-zero exit code: */
> -        ret = -EIO; /* fake errno value */
> -    }
> -    g_free(s);
> -    return ret;
> -}
> -
> -static int stdio_fclose(void *opaque)
> -{
> -    QEMUFileStdio *s = opaque;
> -    int ret = 0;
> -
> -    if (qemu_file_is_writable(s->file)) {
> -        int fd = fileno(s->stdio_file);
> -        struct stat st;
> -
> -        ret = fstat(fd, &st);
> -        if (ret == 0 && S_ISREG(st.st_mode)) {
> -            /*
> -             * If the file handle is a regular file make sure the
> -             * data is flushed to disk before signaling success.
> -             */
> -            ret = fsync(fd);
> -            if (ret != 0) {
> -                ret = -errno;
> -                return ret;
> -            }
> -        }
> -    }
> -    if (fclose(s->stdio_file) == EOF) {
> -        ret = -errno;
> -    }
> -    g_free(s);
> -    return ret;
> -}
> -
> -static const QEMUFileOps stdio_pipe_read_ops = {
> -    .get_fd =     stdio_get_fd,
> -    .get_buffer = stdio_get_buffer,
> -    .close =      stdio_pclose
> -};
> -
> -static const QEMUFileOps stdio_pipe_write_ops = {
> -    .get_fd =     stdio_get_fd,
> -    .put_buffer = stdio_put_buffer,
> -    .close =      stdio_pclose
> -};
> -
> -QEMUFile *qemu_popen_cmd(const char *command, const char *mode)
> -{
> -    FILE *stdio_file;
> -    QEMUFileStdio *s;
> -
> -    if (mode == NULL || (mode[0] != 'r' && mode[0] != 'w') || mode[1] != 0) {
> -        fprintf(stderr, "qemu_popen: Argument validity check failed\n");
> -        return NULL;
> -    }
> -
> -    stdio_file = popen(command, mode);
> -    if (stdio_file == NULL) {
> -        return NULL;
> -    }
> -
> -    s = g_new0(QEMUFileStdio, 1);
> -
> -    s->stdio_file = stdio_file;
> -
> -    if (mode[0] == 'r') {
> -        s->file = qemu_fopen_ops(s, &stdio_pipe_read_ops);
> -    } else {
> -        s->file = qemu_fopen_ops(s, &stdio_pipe_write_ops);
> -    }
> -    return s->file;
> -}
> -
> -static const QEMUFileOps stdio_file_read_ops = {
> -    .get_fd =     stdio_get_fd,
> -    .get_buffer = stdio_get_buffer,
> -    .close =      stdio_fclose
> -};
> -
> -static const QEMUFileOps stdio_file_write_ops = {
> -    .get_fd =     stdio_get_fd,
> -    .put_buffer = stdio_put_buffer,
> -    .close =      stdio_fclose
> -};
> -
> -QEMUFile *qemu_fopen(const char *filename, const char *mode)
> -{
> -    QEMUFileStdio *s;
> -
> -    if (qemu_file_mode_is_not_valid(mode)) {
> -        return NULL;
> -    }
> -
> -    s = g_new0(QEMUFileStdio, 1);
> -
> -    s->stdio_file = fopen(filename, mode);
> -    if (!s->stdio_file) {
> -        goto fail;
> -    }
> -
> -    if (mode[0] == 'w') {
> -        s->file = qemu_fopen_ops(s, &stdio_file_write_ops);
> -    } else {
> -        s->file = qemu_fopen_ops(s, &stdio_file_read_ops);
> -    }
> -    return s->file;
> -fail:
> -    g_free(s);
> -    return NULL;
> -}
> -- 
> 2.5.0
> 
--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK