fdisk: extend -c and -u options to support old DOS stuff

The DOS mode and cylinders as display units are disabled by default
now. For users who need old DOS behavior is it necessary to extend
-c (compatibility) and -u (units) command line options. The change is
backwardly compatible (so people who already uses -u and -c are not
affected with this change). New form:

 -c[=<mode>]   where <mode> is 'dos' or 'nondos' (default)
 -u[=<units>]  where <units> is 'cylinders' or 'sectors' (default)

For example old deprecated DOS behavior could be enabled by:

  fdisk -u=cylinders -c=dos /dev/sda

Signed-off-by: Karel Zak <kzak@redhat.com>

1 files changed, 20 insertions, 8 deletions

diff --git a/fdisk/fdisk.c b/fdisk/fdisk.c
index f1392e7b..99b50aac 100644
--- a/fdisk/fdisk.c
+++ b/fdisk/fdisk.c
@@ -260,9 +260,9 @@ void fatal(enum failure why) {
 " fdisk -s <partition>      give partition size(s) in blocks\n"
 "\nOptions:\n"
 " -b <size>             sector size (512, 1024, 2048 or 4096)\n"
-" -c                    switch off DOS-compatible mode (default)\n"
+" -c[=<mode>]           compatible mode: 'dos' or 'nondos' (default)\n"
 " -h                    print this help text\n"
-" -u                    show sizes in sectors instead of cylinders (default)\n"
+" -u[=<unit>]           dysplay units: 'cylinders' or 'sectors' (default)\n"
 " -v                    print program version\n"
 " -C <number>           specify the number of cylinders\n"
 " -H <number>           specify the number of heads\n"
@@ -1609,8 +1609,11 @@ void change_units(void)
 {
 	display_in_cyl_units = !display_in_cyl_units;
 	update_units();
-	printf(_("Changing display/entry units to %s\n"),
-		str_units(PLURAL));
+
+	if (display_in_cyl_units)
+		printf(_("Changing display/entry units to cylinders (DEPRECATED!)\n"));
+	else
+		printf(_("Changing display/entry units to sectors\n"));
 }
 
 static void
@@ -1630,7 +1633,7 @@ static void
 toggle_dos_compatibility_flag(void) {
 	dos_compatible_flag = ~dos_compatible_flag;
 	if (dos_compatible_flag)
-		printf(_("DOS Compatibility flag is set\n"));
+		printf(_("DOS Compatibility flag is set (DEPRECATED!)\n"));
 	else
 		printf(_("DOS Compatibility flag is not set\n"));
 
@@ -2919,7 +2922,7 @@ main(int argc, char **argv) {
 	bindtextdomain(PACKAGE, LOCALEDIR);
 	textdomain(PACKAGE);
 
-	while ((c = getopt(argc, argv, "b:cC:hH:lsS:uvV")) != -1) {
+	while ((c = getopt(argc, argv, "b:c::C:hH:lsS:u::vV")) != -1) {
 		switch (c) {
 		case 'b':
 			/* Ugly: this sector size is really per device,
@@ -2937,7 +2940,12 @@ main(int argc, char **argv) {
 			user_cylinders = atoi(optarg);
 			break;
 		case 'c':
-			dos_compatible_flag = 0;
+			dos_compatible_flag = 0;	/* default */
+
+			if (optarg && !strcmp(optarg, "=dos"))
+				dos_compatible_flag = ~0;
+			else if (optarg && strcmp(optarg, "=nondos"))
+				fatal(usage);
 			break;
 		case 'h':
 			fatal(help);
@@ -2959,7 +2967,11 @@ main(int argc, char **argv) {
 			opts = 1;
 			break;
 		case 'u':
-			display_in_cyl_units = 0;
+			display_in_cyl_units = 0;		/* default */
+			if (optarg && strcmp(optarg, "=cylinders") == 0)
+				display_in_cyl_units = !display_in_cyl_units;
+			else if (optarg && strcmp(optarg, "=sectors"))
+				fatal(usage);
 			break;
 		case 'V':
 		case 'v':