vi: fix [end] key handling

[oweals/busybox.git] / util-linux / losetup.c

diff --git a/util-linux/losetup.c b/util-linux/losetup.c
index 62a1a7363fbb8cdfffb39b56b76abd9207edc21c..21108d0bfb372fced9e0925ebd1a0037b12c21d4 100644 (file)
--- a/util-linux/losetup.c
+++ b/util-linux/losetup.c
@@ -4,50 +4,73 @@
  *
  * Copyright (C) 2002  Matt Kraai.
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
+//usage:#define losetup_trivial_usage
+//usage:       "[-r] [-o OFS] LOOPDEV FILE - associate loop devices\n"
+//usage:       "       losetup -d LOOPDEV - disassociate\n"
+//usage:       "       losetup [-f] - show"
+//usage:#define losetup_full_usage "\n\n"
+//usage:       "       -o OFS  Start OFS bytes into FILE"
+//usage:     "\n       -r      Read-only"
+//usage:     "\n       -f      Show first free loop device"
+//usage:
+//usage:#define losetup_notes_usage
+//usage:       "No arguments will display all current associations.\n"
+//usage:       "One argument (losetup /dev/loop1) will display the current association\n"
+//usage:       "(if any), or disassociate it (with -d). The display shows the offset\n"
+//usage:       "and filename of the file the loop device is currently bound to.\n\n"
+//usage:       "Two arguments (losetup /dev/loop1 file.img) create a new association,\n"
+//usage:       "with an optional offset (-o 12345). Encryption is not yet supported.\n"
+//usage:       "losetup -f will show the first loop free loop device\n\n"
+
 #include "libbb.h"
 
 int losetup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int losetup_main(int argc, char **argv)
+int losetup_main(int argc UNUSED_PARAM, char **argv)
 {
-       char dev[] = LOOP_NAME"0";
        unsigned opt;
+       int n;
        char *opt_o;
-       char *s;
        unsigned long long offset = 0;
+       enum {
+               OPT_d = (1 << 0),
+               OPT_o = (1 << 1),
+               OPT_f = (1 << 2),
+               OPT_r = (1 << 3), /* must be last */
+       };
 
-       /* max 2 args, all opts are mutially exclusive */
-       opt_complementary = "?2:d--of:o--df:f-do";
-       opt = getopt32(argv, "do:f", &opt_o);
-       argc -= optind;
+       /* max 2 args, -d,-o,-f opts are mutually exclusive */
+       opt_complementary = "?2:d--of:o--df:f--do";
+       opt = getopt32(argv, "do:fr", &opt_o);
        argv += optind;
 
-       if (opt == 0x2) // -o
+       if (opt == OPT_o)
                offset = xatoull(opt_o);
 
-       if (opt == 0x4 && argc) // -f does not take any argument
-               bb_show_usage();
-
-       if (opt == 0x1) { // -d
-               /* detach takes exactly one argument */
-               if (argc != 1)
+       if (opt == OPT_d) {
+               /* -d BLOCKDEV */
+               if (!argv[0] || argv[1])
                        bb_show_usage();
                if (del_loop(argv[0]))
                        bb_simple_perror_msg_and_die(argv[0]);
                return EXIT_SUCCESS;
        }
 
-       if (argc == 2) {
-               /* -o or no option */
-               if (set_loop(&argv[0], argv[1], offset) < 0)
-                       bb_simple_perror_msg_and_die(argv[0]);
-               return EXIT_SUCCESS;
-       }
+       if (argv[0]) {
+               char *s;
 
-       if (argc == 1) {
-               /* -o or no option */
+               if (opt == OPT_f) /* -f should not have arguments */
+                       bb_show_usage();
+
+               if (argv[1]) {
+                       /* [-r] [-o OFS] BLOCKDEV FILE */
+                       if (set_loop(&argv[0], argv[1], offset, (opt / OPT_r)) < 0)
+                               bb_simple_perror_msg_and_die(argv[0]);
+                       return EXIT_SUCCESS;
+               }
+               /* [-r] [-o OFS] BLOCKDEV */
                s = query_loop(argv[0]);
                if (!s)
                        bb_simple_perror_msg_and_die(argv[0]);
@@ -57,23 +80,28 @@ int losetup_main(int argc, char **argv)
                return EXIT_SUCCESS;
        }
 
-       /* -o, -f or no option */
+       /* [-r] [-o OFS|-f] with no params */
+       n = 0;
        while (1) {
+               char *s;
+               char dev[LOOP_NAMESIZE];
+
+               sprintf(dev, LOOP_FORMAT, n);
                s = query_loop(dev);
+               n++;
                if (!s) {
-                       if (opt == 0x4) {
+                       if (n > 9 && errno && errno != ENXIO)
+                               return EXIT_SUCCESS;
+                       if (opt == OPT_f) {
                                puts(dev);
                                return EXIT_SUCCESS;
                        }
                } else {
-                       if (opt != 0x4)
+                       if (opt != OPT_f)
                                printf("%s: %s\n", dev, s);
                        if (ENABLE_FEATURE_CLEAN_UP)
                                free(s);
                }
-
-               if (++dev[sizeof(dev) - 2] > '9')
-                       break;
        }
        return EXIT_SUCCESS;
 }