[Libguestfs] [PATCH v3 01/11] daemon: btrfs: add helper functions mount and umount
Richard W.M. Jones
rjones at redhat.com
Mon Dec 15 16:46:16 UTC 2014
On Fri, Dec 12, 2014 at 03:03:23PM +0800, Hu Tao wrote:
> Signed-off-by: Hu Tao <hutao at cn.fujitsu.com>
> ---
> daemon/btrfs.c | 106 +++++++++++++++++++++++++++++++--------------------------
> 1 file changed, 58 insertions(+), 48 deletions(-)
>
> diff --git a/daemon/btrfs.c b/daemon/btrfs.c
> index 754fdcd..514ba37 100644
> --- a/daemon/btrfs.c
> +++ b/daemon/btrfs.c
> + if (mount_vfs_nochroot ("", NULL, fs, fs_buf, "<internal>") == -1) {
> + if (rmdir (fs_buf) == -1 && errno != ENOENT)
> + reply_with_error ("rmdir: %m\n");
This error path calls reply_with_error twice (the first time in
mount_vfs_nochroot). That's a problem because it would cause protocol
desychronization.
[...]
> + if (command (NULL, &err, str_umount, fs_buf, NULL) == -1) {
> + reply_with_error ("%s", err ? err : "malloc");
> + return -1;
> + }
'err' is always non-NULL here.
There's no need to send an updated patch, as I'm just going to change
this to an fprintf statement before I push it (very soon).
Thanks,
Rich.
> + if (rmdir (fs_buf) == -1 && errno != ENOENT) {
> + reply_with_error ("rmdir: %m\n");
> + return -1;
> + }
> + }
> + free (fs_buf);
> + return 0;
> +}
> +
> guestfs_int_btrfssubvolume_list *
> do_btrfs_subvolume_list (const mountable_t *fs)
> {
> @@ -336,42 +388,10 @@ do_btrfs_subvolume_list (const mountable_t *fs)
>
> /* Execute 'btrfs subvolume list <fs>', and split the output into lines */
> {
> - CLEANUP_FREE char *fs_buf = NULL;
> -
> - if (fs->type == MOUNTABLE_PATH) {
> - fs_buf = sysroot_path (fs->device);
> - if (fs_buf == NULL) {
> - reply_with_perror ("malloc");
> -
> - cmderror:
> - if (fs->type != MOUNTABLE_PATH && fs_buf) {
> - CLEANUP_FREE char *err = NULL;
> - if (command (NULL, &err, str_umount, fs_buf, NULL) == -1)
> - fprintf (stderr, "%s\n", err);
> -
> - if (rmdir (fs_buf) == -1 && errno != ENOENT)
> - fprintf (stderr, "rmdir: %m\n");
> - }
> - return NULL;
> - }
> - }
> -
> - else {
> - fs_buf = strdup ("/tmp/btrfs.XXXXXX");
> - if (fs_buf == NULL) {
> - reply_with_perror ("strdup");
> - goto cmderror;
> - }
> + char *fs_buf = mount (fs);
>
> - if (mkdtemp (fs_buf) == NULL) {
> - reply_with_perror ("mkdtemp");
> - goto cmderror;
> - }
> -
> - if (mount_vfs_nochroot ("", NULL, fs, fs_buf, "<internal>") == -1) {
> - goto cmderror;
> - }
> - }
> + if (!fs_buf)
> + return NULL;
>
> ADD_ARG (argv, i, str_btrfs);
> ADD_ARG (argv, i, "subvolume");
> @@ -382,18 +402,8 @@ do_btrfs_subvolume_list (const mountable_t *fs)
> CLEANUP_FREE char *out = NULL, *errout = NULL;
> int r = commandv (&out, &errout, argv);
>
> - if (fs->type != MOUNTABLE_PATH) {
> - CLEANUP_FREE char *err = NULL;
> - if (command (NULL, &err, str_umount, fs_buf, NULL) == -1) {
> - reply_with_error ("%s", err ? err : "malloc");
> - goto cmderror;
> - }
> -
> - if (rmdir (fs_buf) == -1 && errno != ENOENT) {
> - reply_with_error ("rmdir: %m\n");
> - goto cmderror;
> - }
> - }
> + if (umount (fs_buf, fs) != 0)
> + return NULL;
>
> if (r == -1) {
> CLEANUP_FREE char *fs_desc = mountable_to_string (fs);
> @@ -401,7 +411,7 @@ do_btrfs_subvolume_list (const mountable_t *fs)
> fprintf (stderr, "malloc: %m");
> }
> reply_with_error ("%s: %s", fs_desc ? fs_desc : "malloc", errout);
> - goto cmderror;
> + return NULL;
> }
>
> lines = split_lines (out);
> --
> 1.9.3
>
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--
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