diff --git a/include/usage.h b/include/usage.h index 09c8fa7d1..b028f5a5c 100644 --- a/include/usage.h +++ b/include/usage.h @@ -1868,19 +1868,21 @@ " -f Output data as the log grows" #define losetup_trivial_usage \ - "[-o OFFSET] [-d] LOOPDEVICE [FILE]]" + "[-o OFS] LOOPDEV FILE - associate loop devices\n" \ + " losetup -d LOOPDEV - disassociate\n" \ + " losetup [-f] - show" #define losetup_full_usage \ - "(Dis)associate LOOPDEVICE with FILE, or display current associations" \ - "\n\nOptions:\n" \ - " -d Disassociate LOOPDEVICE\n" \ - " -o OFFSET Start OFFSET bytes into FILE" + "Options:\n" \ + " -o OFS Start OFS bytes into FILE\n" \ + " -f Show first free loop device" #define losetup_notes_usage \ "No arguments will display all current associations.\n" \ "One argument (losetup /dev/loop1) will display the current association\n" \ "(if any), or disassociate it (with -d). The display shows the offset\n" \ "and filename of the file the loop device is currently bound to.\n\n" \ "Two arguments (losetup /dev/loop1 file.img) create a new association,\n" \ - "with an optional offset (-o 12345). Encryption is not yet supported.\n\n" + "with an optional offset (-o 12345). Encryption is not yet supported.\n" \ + "losetup -f will show the first loop free loop device\n\n" #define ls_trivial_usage \ "[-1Aa" USE_FEATURE_LS_TIMESTAMPS("c") "Cd" \ diff --git a/util-linux/losetup.c b/util-linux/losetup.c index 9409cdff5..57e8569dc 100644 --- a/util-linux/losetup.c +++ b/util-linux/losetup.c @@ -14,54 +14,68 @@ int losetup_main(int argc, char **argv); int losetup_main(int argc, char **argv) { + char dev[] = LOOP_NAME"0"; unsigned opt; char *opt_o; + char *s; unsigned long long offset = 0; - opt = getopt32(argv, "do:", &opt_o); + /* 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; argv += optind; - if (opt == 0x3) // -d + -o (illegal) + if (opt == 0x2) // -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) bb_show_usage(); - if (!del_loop(argv[0])) - return EXIT_SUCCESS; - bb_perror_nomsg_and_die(); + if (del_loop(argv[0])) + bb_perror_nomsg_and_die(); + return EXIT_SUCCESS; } - if (opt == 0x2) // -o - offset = xatoull(opt_o); - - /* -o or no option */ - if (argc == 2) { + /* -o or no option */ if (set_loop(&argv[0], argv[1], offset) < 0) bb_perror_nomsg_and_die(); - } else if (argc == 1) { - char *s = query_loop(argv[0]); + return EXIT_SUCCESS; + } + + if (argc == 1) { + /* -o or no option */ + s = query_loop(argv[0]); if (!s) bb_perror_nomsg_and_die(); printf("%s: %s\n", argv[0], s); if (ENABLE_FEATURE_CLEAN_UP) free(s); - } else { - char dev[sizeof(LOOP_NAME"0")] = LOOP_NAME"0"; - char c; - for (c = '0'; c <= '9'; ++c) { - char *s; - dev[sizeof(LOOP_NAME"0")-2] = c; - s = query_loop(dev); - if (s) { - printf("%s: %s\n", dev, s); - if (ENABLE_FEATURE_CLEAN_UP) - free(s); + return EXIT_SUCCESS; + } + + /* -o, -f or no option */ + while (1) { + s = query_loop(dev); + if (!s) { + if (opt == 0x4) { + printf("%s\n", dev); + return EXIT_SUCCESS; } + } else { + if (opt != 0x4) + printf("%s: %s\n", dev, s); + if (ENABLE_FEATURE_CLEAN_UP) + free(s); } + + if (++dev[sizeof(dev) - 2] > '9') + break; } return EXIT_SUCCESS; }