- add -r option to losetup to create a read-only loop

--- util-linux-2.13-pre6/mount/lomount.c.ronly	2006-11-01 14:14:14.000000000 +0100
+++ util-linux-2.13-pre6/mount/lomount.c	2006-11-01 15:01:52.000000000 +0100
@@ -444,7 +444,8 @@
   "  %1$s -d loop_device                                    # delete\n"
   "  %1$s -f                                                # find unused\n"
   "  %1$s -a                                                # list all used\n"
-  "  %1$s [-e encryption] [-o offset] {-f|loop_device} file # setup\n"),
+  "  %1$s -r                                                # read-only loop\n"
+  "  %1$s [-e encryption] [-o offset] [-r] {-f|loop_device} file # setup\n"),
 		progname);
 	exit(1);
 }
@@ -497,11 +498,14 @@
 	if ((p = strrchr(progname, '/')) != NULL)
 		progname = p+1;
 
-	while ((c = getopt(argc, argv, "ade:E:fo:p:v")) != -1) {
+	while ((c = getopt(argc, argv, "ade:E:fo:p:vr")) != -1) {
 		switch (c) {
 		case 'a':
 			all = 1;
 			break;
+		case 'r':
+			ro = 1;
+			break;
 		case 'd':
 			delete = 1;
 			break;
--- util-linux-2.13-pre6/mount/losetup.8.ronly	2006-11-01 14:49:14.000000000 +0100
+++ util-linux-2.13-pre6/mount/losetup.8	2006-11-01 15:06:21.000000000 +0100
@@ -35,6 +35,7 @@
 .IR offset ]
 .RB [ \-p
 .IR pfd ]
+.RB [ \-r ]
 .in +8
 .RB { \-f | \fIloop_device\fP }
 .I file
@@ -87,6 +88,8 @@
 Read the passphrase from file descriptor with number
 .I num
 instead of from the terminal.
+.IP \fB\-r\fP
+Setup read-only loop device.
 .SH RETURN VALUE
 .B losetup
 returns 0 on success, nonzero on failure. When