From d5ea873fcbf00b841f0511a26fb341364a5c6425 Mon Sep 17 00:00:00 2001
From: Eric Sandeen <sandeen@sandeen.net>
Date: Tue, 8 Jun 2010 20:03:39 +0000
Subject: [PATCH] xfstests: resolve symlinked devices to real paths

If you try running xfstests on lvm volumes which are symlinks,
it'll fail to run several tests because our _require_scratch
framework ultimately uses lstat not stat, and does not think
the lvm device (which is usually a symlink to a dm-X device)
is a block device.  Sigh.

Last try at this - just resolve any symlinked devicenames
into their realpath(3) in common.config.

This actually seems to work.

Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Reviewed-by: Rich Johnston <rjohnston@sgi.com>
Signed-off-by: Rich Johnston <rjohnston@sgi.com>
---
 common.config  |  9 +++++++++
 src/realpath.c | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 src/realpath.c

diff --git a/common.config b/common.config
index 57f505de..585b1505 100644
--- a/common.config
+++ b/common.config
@@ -220,6 +220,15 @@ else
     known_hosts
 fi
 
+# Scripts just don't deal well with symlinked devices
+if [ -L $TEST_DEV ]; then
+        TEST_DEV=`src/realpath $TEST_DEV`
+fi
+
+if [ -L $SCRATCH_DEV ]; then
+        SCRATCH_DEV=`src/realpath $SCRATCH_DEV`
+fi
+
 echo $TEST_DEV | grep -q ":" > /dev/null 2>&1
 if [ ! -b "$TEST_DEV" -a "$?" != "0" ]; then
     echo "common.config: Error: \$TEST_DEV ($TEST_DEV) is not a block device or a NFS filesystem"
diff --git a/src/realpath.c b/src/realpath.c
new file mode 100644
index 00000000..997b1aa9
--- /dev/null
+++ b/src/realpath.c
@@ -0,0 +1,32 @@
+#include <limits.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+/*
+ * Simple wrapper around realpath(3) to get absolute path
+ * to a device name; many xfstests scripts don't cope well
+ * with symlinked devices due to differences in /proc/mounts,
+ * /etc/mtab, mount output, etc.
+ */
+
+int main(int argc, char *argv[])
+{
+	char path[PATH_MAX];
+	char resolved_path[PATH_MAX];
+
+	if (argc != 2) {
+		printf("Usage: %s <filename>\n", argv[0]);
+		return 1;
+	}
+
+	strncpy(path, argv[1], PATH_MAX-1);
+
+	if (!realpath(path, resolved_path)) {
+		perror("Failed to resolve path for %s");
+		return 1;
+	}
+
+	printf("%s\n", resolved_path);
+	return 0;
+}
-- 
2.30.2