busybox/util-linux/losetup.c
Mandeep Singh Baines 7991d45446 losetup: fix util-linux compatibility
Added -a support. Also made sure -f works as follows:

losetup [-r] [-o offset] {-f|loopdev} file

Removed support for 'losetup -r' with no arguments.

Signed-off-by: Mandeep Singh Baines <msb@chromium.org>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2013-03-12 16:31:25 -04:00

122 lines
2.9 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini losetup implementation for busybox
*
* Copyright (C) 2002 Matt Kraai.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
//usage:#define losetup_trivial_usage
//usage: "[-r] [-o OFS] {-f|LOOPDEV} FILE - associate loop devices\n"
//usage: " losetup -d LOOPDEV - disassociate\n"
//usage: " losetup -a - show status of all\n"
//usage: " losetup -f - show next available"
//usage:#define losetup_full_usage "\n\n"
//usage: " -o OFS Start OFS bytes into FILE"
//usage: "\n -r Read-only"
//usage: "\n -f Show/find first free loop device"
//usage:
//usage:#define losetup_notes_usage
//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 UNUSED_PARAM, char **argv)
{
unsigned opt;
char *opt_o;
char dev[LOOP_NAMESIZE];
enum {
OPT_d = (1 << 0),
OPT_o = (1 << 1),
OPT_f = (1 << 2),
OPT_a = (1 << 3),
OPT_r = (1 << 4), /* must be last */
};
opt_complementary = "?2:d--ofar:a--ofr";
opt = getopt32(argv, "do:far", &opt_o);
argv += optind;
/* LOOPDEV */
if (!opt && argv[0] && !argv[1]) {
char *s;
s = query_loop(argv[0]);
if (!s)
bb_simple_perror_msg_and_die(argv[0]);
printf("%s: %s\n", argv[0], s);
if (ENABLE_FEATURE_CLEAN_UP)
free(s);
return EXIT_SUCCESS;
}
/* -d LOOPDEV */
if (opt == OPT_d) {
if (del_loop(argv[0]))
bb_simple_perror_msg_and_die(argv[0]);
return EXIT_SUCCESS;
}
/* -a */
if (opt == OPT_a) {
int n;
for (n = 0; n < 10; n++) {
char *s;
sprintf(dev, LOOP_FORMAT, n);
s = query_loop(dev);
if (s) {
printf("%s: %s\n", dev, s);
if (ENABLE_FEATURE_CLEAN_UP)
free(s);
}
}
return EXIT_SUCCESS;
}
/* contains -f */
if (opt & OPT_f) {
char *s;
int n = 0;
do {
sprintf(dev, LOOP_FORMAT, n);
s = query_loop(dev);
if (s && ENABLE_FEATURE_CLEAN_UP)
free(s);
} while (s);
if ((opt == OPT_f) && !argv[0]) {
puts(dev);
return EXIT_SUCCESS;
}
}
/* [-r] [-o OFS] {-f|LOOPDEV} FILE */
if (argv[0] && ((opt & OPT_f) || argv[1])) {
unsigned long long offset = 0;
char *d = dev;
if (opt == OPT_o)
offset = xatoull(opt_o);
if (opt != OPT_f)
d = *(argv++);
if (argv[0]) {
if (set_loop(&d, argv[0], offset, (opt / OPT_r)) < 0)
bb_simple_perror_msg_and_die(argv[0]);
return EXIT_SUCCESS;
}
}
bb_show_usage();
return EXIT_FAILURE;
}