Allow libufs(3) functions to operate on a regular file. This makes it possible to

use almost anything that uses libufs(3) against a file as an unprivileged user, e.g.
tunefs(8) and dumpfs(8) against a makefs(8)-created image.

Prodded by:	kensmith

2 files changed, 5 insertions, 2 deletions

diff --git a/lib/libufs/type.c b/lib/libufs/type.c
index 9b7470a..8a553be 100644
--- a/lib/libufs/type.c
+++ b/lib/libufs/type.c
@@ -108,7 +108,10 @@ again:	if ((ret = stat(name, &st)) < 0) {
 		 */
 		name = oname;
 	}
-	if (ret >= 0 && S_ISCHR(st.st_mode)) {
+	if (ret >= 0 && S_ISREG(st.st_mode)) {
+		/* Possibly a disk image, give it a try.  */
+		;
+	} else if (ret >= 0 && S_ISCHR(st.st_mode)) {
 		/* This is what we need, do nothing. */
 		;
 	} else if ((fs = getfsfile(name)) != NULL) {
diff --git a/lib/libufs/ufs_disk_close.3 b/lib/libufs/ufs_disk_close.3
index a659116..25a059e 100644
--- a/lib/libufs/ufs_disk_close.3
+++ b/lib/libufs/ufs_disk_close.3
@@ -53,7 +53,7 @@ and populate the structure pointed to by
 The disk is opened read-only.
 The specified
 .Fa name
-may be either a mountpoint, or a device name.
+may be either a mountpoint, a device name or a filesystem image.
 The
 .Fn ufs_disk_fillout
 function assumes there is a valid superblock and will fail if not,