losetup: assorted fixes. Closes 6314

"losetup -d" was not complaining that LOOPDEV is missing.
"losetup -a" was listing only up to /dev/loop9.
"losetup -f" looped forever if llop0 was taken, and never tried
anything after /dev/loop9.
"-o" with other options (say, -r) had no effect.

function                                             old     new   delta
losetup_main                                         376     419     +43

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2013-06-27 03:45:16 +02:00
parent 879f008a8f
commit 4928e9f7d0
2 changed files with 23 additions and 18 deletions

View File

@ -1803,7 +1803,7 @@ extern const char bb_default_login_shell[] ALIGN1;
# define VC_4 "/dev/vc/4" # define VC_4 "/dev/vc/4"
# define VC_5 "/dev/vc/5" # define VC_5 "/dev/vc/5"
# define VC_FORMAT "/dev/vc/%d" # define VC_FORMAT "/dev/vc/%d"
# define LOOP_FORMAT "/dev/loop/%d" # define LOOP_FORMAT "/dev/loop/%u"
# define LOOP_NAMESIZE (sizeof("/dev/loop/") + sizeof(int)*3 + 1) # define LOOP_NAMESIZE (sizeof("/dev/loop/") + sizeof(int)*3 + 1)
# define LOOP_NAME "/dev/loop/" # define LOOP_NAME "/dev/loop/"
# define FB_0 "/dev/fb/0" # define FB_0 "/dev/fb/0"
@ -1816,7 +1816,7 @@ extern const char bb_default_login_shell[] ALIGN1;
# define VC_4 "/dev/tty4" # define VC_4 "/dev/tty4"
# define VC_5 "/dev/tty5" # define VC_5 "/dev/tty5"
# define VC_FORMAT "/dev/tty%d" # define VC_FORMAT "/dev/tty%d"
# define LOOP_FORMAT "/dev/loop%d" # define LOOP_FORMAT "/dev/loop%u"
# define LOOP_NAMESIZE (sizeof("/dev/loop") + sizeof(int)*3 + 1) # define LOOP_NAMESIZE (sizeof("/dev/loop") + sizeof(int)*3 + 1)
# define LOOP_NAME "/dev/loop" # define LOOP_NAME "/dev/loop"
# define FB_0 "/dev/fb0" # define FB_0 "/dev/fb0"

View File

@ -10,12 +10,12 @@
//usage:#define losetup_trivial_usage //usage:#define losetup_trivial_usage
//usage: "[-r] [-o OFS] {-f|LOOPDEV} FILE - associate loop devices\n" //usage: "[-r] [-o OFS] {-f|LOOPDEV} FILE - associate loop devices\n"
//usage: " losetup -d LOOPDEV - disassociate\n" //usage: " losetup -d LOOPDEV - disassociate\n"
//usage: " losetup -a - show status of all\n" //usage: " losetup -a - show status\n"
//usage: " losetup -f - show next available" //usage: " losetup -f - show next free loop device"
//usage:#define losetup_full_usage "\n\n" //usage:#define losetup_full_usage "\n\n"
//usage: " -o OFS Start OFS bytes into FILE" //usage: " -o OFS Start OFS bytes into FILE"
//usage: "\n -r Read-only" //usage: "\n -r Read-only"
//usage: "\n -f Show/find first free loop device" //usage: "\n -f Show/use next free loop device"
//usage: //usage:
//usage:#define losetup_notes_usage //usage:#define losetup_notes_usage
//usage: "One argument (losetup /dev/loop1) will display the current association\n" //usage: "One argument (losetup /dev/loop1) will display the current association\n"
@ -27,6 +27,10 @@
#include "libbb.h" #include "libbb.h"
/* 1048575 is a max possible minor number in Linux circa 2010 */
/* for now use something less extreme */
#define MAX_LOOP_NUM 1023
int losetup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int losetup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int losetup_main(int argc UNUSED_PARAM, char **argv) int losetup_main(int argc UNUSED_PARAM, char **argv)
{ {
@ -59,7 +63,7 @@ int losetup_main(int argc UNUSED_PARAM, char **argv)
} }
/* -d LOOPDEV */ /* -d LOOPDEV */
if (opt == OPT_d) { if (opt == OPT_d && argv[0]) {
if (del_loop(argv[0])) if (del_loop(argv[0]))
bb_simple_perror_msg_and_die(argv[0]); bb_simple_perror_msg_and_die(argv[0]);
return EXIT_SUCCESS; return EXIT_SUCCESS;
@ -68,15 +72,14 @@ int losetup_main(int argc UNUSED_PARAM, char **argv)
/* -a */ /* -a */
if (opt == OPT_a) { if (opt == OPT_a) {
int n; int n;
for (n = 0; n < 10; n++) { for (n = 0; n < MAX_LOOP_NUM; n++) {
char *s; char *s;
sprintf(dev, LOOP_FORMAT, n); sprintf(dev, LOOP_FORMAT, n);
s = query_loop(dev); s = query_loop(dev);
if (s) { if (s) {
printf("%s: %s\n", dev, s); printf("%s: %s\n", dev, s);
if (ENABLE_FEATURE_CLEAN_UP) free(s);
free(s);
} }
} }
return EXIT_SUCCESS; return EXIT_SUCCESS;
@ -88,11 +91,13 @@ int losetup_main(int argc UNUSED_PARAM, char **argv)
int n = 0; int n = 0;
do { do {
sprintf(dev, LOOP_FORMAT, n); if (n > MAX_LOOP_NUM)
bb_error_msg_and_die("no free loop devices");
sprintf(dev, LOOP_FORMAT, n++);
s = query_loop(dev); s = query_loop(dev);
if (s && ENABLE_FEATURE_CLEAN_UP) free(s);
free(s);
} while (s); } while (s);
/* now: dev is next free "/dev/loopN" */
if ((opt == OPT_f) && !argv[0]) { if ((opt == OPT_f) && !argv[0]) {
puts(dev); puts(dev);
return EXIT_SUCCESS; return EXIT_SUCCESS;
@ -104,18 +109,18 @@ int losetup_main(int argc UNUSED_PARAM, char **argv)
unsigned long long offset = 0; unsigned long long offset = 0;
char *d = dev; char *d = dev;
if (opt == OPT_o) if (opt & OPT_o)
offset = xatoull(opt_o); offset = xatoull(opt_o);
if (opt != OPT_f) if (!(opt & OPT_f))
d = *(argv++); d = *argv++;
if (argv[0]) { if (argv[0]) {
if (set_loop(&d, argv[0], offset, (opt / OPT_r)) < 0) if (set_loop(&d, argv[0], offset, (opt & OPT_r)) < 0)
bb_simple_perror_msg_and_die(argv[0]); bb_simple_perror_msg_and_die(argv[0]);
return EXIT_SUCCESS; return EXIT_SUCCESS;
} }
} }
bb_show_usage(); bb_show_usage(); /* does not return */
return EXIT_FAILURE; /*return EXIT_FAILURE;*/
} }