[PATCH] btrfs-progs: Fix btrfs fi show by uuid and label

[PATCH] btrfs-progs: Fix btrfs fi show by uuid and label

[Justin Maggard]

Commit 8be2fff (btrfs-progs: apply realpath for btrfs fi
show when mount point is given) changed the behavior of
btrfs fi show to return an error if the call to realpath()
failed.  This broke the ability to specify a filesystem by
uuid or label.

So let's not consider a failed call to realpath() as an
error.  If the user really specified a bad device, just
return nothing like we did before.
---
 cmds-filesystem.c |    9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/cmds-filesystem.c b/cmds-filesystem.c
index 8f037dd..a654e6f 100644
--- a/cmds-filesystem.c
+++ b/cmds-filesystem.c
@@ -901,13 +901,8 @@ static int cmd_show(int argc, char **argv)
 		 *     realpath do  /mnt/btrfs/  => /mnt/btrfs
 		 *     which shall be recognized by btrfs_scan_kernel()
 		 */
-		if (!realpath(search, path)) {
-			fprintf(stderr, "ERROR: Could not show %s: %s\n",
-					search, strerror(errno));
-			return 1;
-		}
-
-		search = path;
+		if (realpath(search, path))
+			search = path;
 
 		/*
 		 * Needs special handling if input arg is block dev And if
-- 
1.7.10.4

Re: [PATCH] btrfs-progs: Fix btrfs fi show by uuid and label

[Gui Hecheng]

On Tue, 2014-12-23 at 11:34 -0800, Justin Maggard wrote:
> Commit 8be2fff (btrfs-progs: apply realpath for btrfs fi
> show when mount point is given) changed the behavior of
> btrfs fi show to return an error if the call to realpath()
> failed.  This broke the ability to specify a filesystem by
> uuid or label.

Oh, that's my fault, thanks for correcting this.

> So let's not consider a failed call to realpath() as an
> error.  If the user really specified a bad device, just
> return nothing like we did before.
> ---
>  cmds-filesystem.c |    9 ++-------
>  1 file changed, 2 insertions(+), 7 deletions(-)
> 
> diff --git a/cmds-filesystem.c b/cmds-filesystem.c
> index 8f037dd..a654e6f 100644
> --- a/cmds-filesystem.c
> +++ b/cmds-filesystem.c
> @@ -901,13 +901,8 @@ static int cmd_show(int argc, char **argv)
>  		 *     realpath do  /mnt/btrfs/  => /mnt/btrfs
>  		 *     which shall be recognized by btrfs_scan_kernel()
>  		 */
> -		if (!realpath(search, path)) {
> -			fprintf(stderr, "ERROR: Could not show %s: %s\n",
> -					search, strerror(errno));
> -			return 1;
> -		}
> -
> -		search = path;
> +		if (realpath(search, path))
> +			search = path;

This looks nice and stay consistent with the behavior before my faulty
commit.

Reviewed-by: Gui Hecheng <guihc.fnst@cn.fujitsu.com>

Thanks,
Gui

>  		/*
>  		 * Needs special handling if input arg is block dev And if