[Cluster-devel] [PATCH] mkfs.gfs2: Follow symlinks before checking device contents

[Andrew Price <anprice@redhat.com>]

When using symlinks with mkfs.gfs2 it reports what the symlink points
to instead of the contents of the device, like so:

 # ./mkfs.gfs2 -p lock_nolock /dev/vg/test
 This will destroy any data on /dev/vg/test.
 It appears to contain: symbolic link to `../dm-3'

This patch resolves symlinks before checking the device contents to make
the output more informative:

 # ./mkfs.gfs2 -p lock_nolock /dev/vg/test
 This will destroy any data on /dev/vg/test.
 It appears to contain: GFS2 Filesystem (blocksize 4096, lockproto lock_nolock)

Signed-off-by: Andrew Price <anprice@redhat.com>
---
 gfs2/mkfs/main_mkfs.c |    9 ++++++++-
 1 files changed, 8 insertions(+), 1 deletions(-)

diff --git a/gfs2/mkfs/main_mkfs.c b/gfs2/mkfs/main_mkfs.c
index e6b00a0..f8e4741 100644
--- a/gfs2/mkfs/main_mkfs.c
+++ b/gfs2/mkfs/main_mkfs.c
@@ -531,6 +531,7 @@ void main_mkfs(int argc, char *argv[])
 	int error;
 	int rgsize_specified = 0;
 	unsigned char uuid[16];
+	char *absname;
 
 	memset(sdp, 0, sizeof(struct gfs2_sbd));
 	sdp->bsize = -1;
@@ -560,11 +561,17 @@ void main_mkfs(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
+	absname = canonicalize_file_name(sdp->device_name);
+	if (absname == NULL) {
+		perror(_("Could not find the absolute path of the device"));
+		exit(EXIT_FAILURE);
+	}
 	if (!sdp->override) {
 		printf( _("This will destroy any data on %s.\n"), sdp->device_name);
-		check_dev_content(sdp->device_name);
+		check_dev_content(absname);
 		are_you_sure();
 	}
+	free(absname);
 
 	if (sdp->bsize == -1) {
 		if (S_ISREG(sdp->dinfo.stat.st_mode))
-- 
1.7.7.6