libext2fs: display partial path if fs corrupted in ext2fs_get_pathname()

The function ext2fs_get_pathname() used to return EXT2_ET_NO_DIRECTORY
if one of the directories in an inode's pathname is not a directory.
This is not very useful in an emergency, when the file system is
corrupted.  This commit will cause ext2fs_get_pathname() to return a
partial pathname, which should help system administrators trying to
use debugfs to investigate a corrupted file system.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

1 files changed, 16 insertions, 5 deletions

diff --git a/lib/ext2fs/get_pathname.c b/lib/ext2fs/get_pathname.c
index e259eee7..33209949 100644
--- a/lib/ext2fs/get_pathname.c
+++ b/lib/ext2fs/get_pathname.c
@@ -74,7 +74,7 @@ static errcode_t ext2fs_get_pathname_int(ext2_filsys fs, ext2_ino_t dir,
 					 char *buf, char **name)
 {
 	struct get_pathname_struct gp;
-	char	*parent_name, *ret;
+	char	*parent_name = 0, *ret;
 	errcode_t	retval;
 
 	if (dir == ino) {
@@ -99,7 +99,19 @@ static errcode_t ext2fs_get_pathname_int(ext2_filsys fs, ext2_ino_t dir,
 	gp.errcode = 0;
 
 	retval = ext2fs_dir_iterate(fs, dir, 0, buf, get_pathname_proc, &gp);
-	if (retval)
+	if (retval == EXT2_ET_NO_DIRECTORY) {
+		char buf[32];
+
+		if (ino)
+			snprintf(buf, sizeof(buf), "<%u>/<%u>", dir, ino);
+		else
+			snprintf(buf, sizeof(buf), "<%u>", dir);
+		retval = ext2fs_get_mem(strlen(buf)+1, name);
+		if (retval)
+			goto cleanup;
+		strcpy(*name, buf);
+		return 0;
+	} else if (retval)
 		goto cleanup;
 	if (gp.errcode) {
 		retval = gp.errcode;
@@ -132,12 +144,11 @@ static errcode_t ext2fs_get_pathname_int(ext2_filsys fs, ext2_ino_t dir,
 	else
 		strcat(ret, "???");
 	*name = ret;
-	ext2fs_free_mem(&parent_name);
 	retval = 0;
 
 cleanup:
-	if (gp.name)
-		ext2fs_free_mem(&gp.name);
+	ext2fs_free_mem(&parent_name);
+	ext2fs_free_mem(&gp.name);
 	return retval;
 }