mount and umount could leak loop device allocations causing the system to
quickly run out. Also disable init's SIGHUP handler during shutdown.
-Erik
diff --git a/Changelog b/Changelog
index 4dbb46e..46b2a1f 100644
--- a/Changelog
+++ b/Changelog
@@ -32,6 +32,11 @@
tail -f work only with a single file. This reduced tail
from 6k to 2.4k. The bigger/more featured tail can still be
had by disabling BB_FEATURE_SIMPLE_TAIL in dusybox.defs.h
+ * Ping now falls back to doing the right thing if /etc/protocols
+ turns up missing.
+ * Fixed mount and umount. Previously they could leak loop device
+ allocations, causing the system to quickly run out. Fix for umount
+ by Ben Collins <bcollins@debian.org>, and mount was fixed by me.
-Erik Andersen
diff --git a/init.c b/init.c
index 5b80cc5..09540ff 100644
--- a/init.c
+++ b/init.c
@@ -359,6 +359,7 @@
signal(SIGUSR2, SIG_DFL);
signal(SIGINT, SIG_DFL);
signal(SIGTERM, SIG_DFL);
+ signal(SIGHUP, SIG_DFL);
if ((fd = device_open(terminal, O_RDWR)) < 0) {
message(LOG|CONSOLE, "Bummer, can't open %s\r\n", terminal);
@@ -458,6 +459,9 @@
#ifndef DEBUG_INIT
static void shutdown_system(void)
{
+ /* first disable our SIGHUP signal */
+ signal(SIGHUP, SIG_DFL);
+
/* Allow Ctrl-Alt-Del to reboot system. */
reboot(RB_ENABLE_CAD);
message(CONSOLE, "\r\nThe system is going down NOW !!\r\n");
diff --git a/init/init.c b/init/init.c
index 5b80cc5..09540ff 100644
--- a/init/init.c
+++ b/init/init.c
@@ -359,6 +359,7 @@
signal(SIGUSR2, SIG_DFL);
signal(SIGINT, SIG_DFL);
signal(SIGTERM, SIG_DFL);
+ signal(SIGHUP, SIG_DFL);
if ((fd = device_open(terminal, O_RDWR)) < 0) {
message(LOG|CONSOLE, "Bummer, can't open %s\r\n", terminal);
@@ -458,6 +459,9 @@
#ifndef DEBUG_INIT
static void shutdown_system(void)
{
+ /* first disable our SIGHUP signal */
+ signal(SIGHUP, SIG_DFL);
+
/* Allow Ctrl-Alt-Del to reboot system. */
reboot(RB_ENABLE_CAD);
message(CONSOLE, "\r\nThe system is going down NOW !!\r\n");
diff --git a/internal.h b/internal.h
index 500a63e..9611c19 100644
--- a/internal.h
+++ b/internal.h
@@ -175,6 +175,10 @@
extern long getNum (const char *cp);
extern pid_t findInitPid();
+#if defined BB_FEATURE_MOUNT_LOOP
+extern int del_loop(const char *device);
+#endif
+
#if defined BB_GUNZIP || defined BB_GZIP || defined BB_PRINTF || defined BB_TAIL
extern void *xmalloc (size_t size);
extern void error(char *msg);
diff --git a/mount.c b/mount.c
index 709c7fc..3c1568a 100644
--- a/mount.c
+++ b/mount.c
@@ -127,11 +127,11 @@
specialfile = find_unused_loop_device();
if (specialfile == NULL) {
fprintf(stderr, "Could not find a spare loop device\n");
- exit(1);
+ return( FALSE);
}
if (set_loop (specialfile, lofile, 0, &loro)) {
fprintf(stderr, "Could not setup loop device\n");
- exit(1);
+ return( FALSE);
}
if (!(flags & MS_RDONLY) && loro) { /* loop is ro, but wanted rw */
fprintf(stderr, "WARNING: loop device is read-only\n");
@@ -141,15 +141,26 @@
#endif
status=mount(specialfile, dir, filesystemtype, flags, string_flags);
}
-#if defined BB_MTAB
+
+
+ /* If the mount was sucessful, do anything needed, then return TRUE */
if (status == 0) {
- if (useMtab==TRUE)
+
+#if defined BB_MTAB
+ if (useMtab==TRUE) {
write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
- return 0;
- }
- else
+ }
#endif
- return(status);
+ return( TRUE);
+ }
+
+ /* Bummer. mount failed. Clean up */
+#if defined BB_FEATURE_MOUNT_LOOP
+ if (specialfile != NULL) {
+ del_loop(specialfile);
+ }
+#endif
+ return( FALSE);
}
@@ -166,6 +177,75 @@
#endif
+#if defined BB_FEATURE_MOUNT_LOOP
+static int set_loop(const char *device, const char *file, int offset, int *loopro)
+{
+ struct loop_info loopinfo;
+ int fd, ffd, mode;
+
+ mode = *loopro ? O_RDONLY : O_RDWR;
+ if ((ffd = open (file, mode)) < 0 && !*loopro
+ && (errno != EROFS || (ffd = open (file, mode = O_RDONLY)) < 0)) {
+ perror (file);
+ return 1;
+ }
+ if ((fd = open (device, mode)) < 0) {
+ close(ffd);
+ perror (device);
+ return 1;
+ }
+ *loopro = (mode == O_RDONLY);
+
+ memset(&loopinfo, 0, sizeof(loopinfo));
+ strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
+ loopinfo.lo_name[LO_NAME_SIZE-1] = 0;
+
+ loopinfo.lo_offset = offset;
+
+ loopinfo.lo_encrypt_key_size = 0;
+ if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
+ perror("ioctl: LOOP_SET_FD");
+ close(fd);
+ close(ffd);
+ return 1;
+ }
+ if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
+ (void) ioctl(fd, LOOP_CLR_FD, 0);
+ perror("ioctl: LOOP_SET_STATUS");
+ close(fd);
+ close(ffd);
+ return 1;
+ }
+ close(fd);
+ close(ffd);
+ return 0;
+}
+
+char *find_unused_loop_device (void)
+{
+ char dev[20];
+ int i, fd;
+ struct stat statbuf;
+ struct loop_info loopinfo;
+
+ for(i = 0; i <= 7; i++) {
+ sprintf(dev, "/dev/loop%d", i);
+ if (stat (dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
+ if ((fd = open (dev, O_RDONLY)) >= 0) {
+ if(ioctl (fd, LOOP_GET_STATUS, &loopinfo) == -1) {
+ if (errno == ENXIO) { /* probably free */
+ close (fd);
+ return strdup(dev);
+ }
+ }
+ close (fd);
+ }
+ }
+ }
+ return NULL;
+}
+#endif /* BB_FEATURE_MOUNT_LOOP */
+
/* Seperate standard mount options from the nonstandard string options */
static void
parse_mount_options ( char *options, unsigned long *flags, char *strflags)
@@ -240,7 +320,7 @@
status = do_mount (blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags, useMtab,
fakeIt, mtab_opts);
- if (status == 0)
+ if (status == TRUE)
break;
}
}
@@ -253,7 +333,7 @@
fakeIt, mtab_opts);
}
- if (status) {
+ if (status==FALSE) {
fprintf (stderr, "Mounting %s on %s failed: %s\n",
blockDevice, directory, strerror(errno));
return (FALSE);
@@ -400,70 +480,3 @@
usage( mount_usage);
}
-#if defined BB_FEATURE_MOUNT_LOOP
-static int set_loop(const char *device, const char *file, int offset, int *loopro)
-{
- struct loop_info loopinfo;
- int fd, ffd, mode;
-
- mode = *loopro ? O_RDONLY : O_RDWR;
- if ((ffd = open (file, mode)) < 0 && !*loopro
- && (errno != EROFS || (ffd = open (file, mode = O_RDONLY)) < 0)) {
- perror (file);
- return 1;
- }
- if ((fd = open (device, mode)) < 0) {
- close(ffd);
- perror (device);
- return 1;
- }
- *loopro = (mode == O_RDONLY);
-
- memset(&loopinfo, 0, sizeof(loopinfo));
- strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
- loopinfo.lo_name[LO_NAME_SIZE-1] = 0;
-
- loopinfo.lo_offset = offset;
-
- loopinfo.lo_encrypt_key_size = 0;
- if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
- perror("ioctl: LOOP_SET_FD");
- close(fd);
- close(ffd);
- return 1;
- }
- if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
- (void) ioctl(fd, LOOP_CLR_FD, 0);
- perror("ioctl: LOOP_SET_STATUS");
- close(fd);
- close(ffd);
- return 1;
- }
- close(fd);
- close(ffd);
- return 0;
-}
-
-char *find_unused_loop_device (void)
-{
- char dev[20];
- int i, fd;
- struct stat statbuf;
- struct loop_info loopinfo;
-
- for(i = 0; i <= 7; i++) {
- sprintf(dev, "/dev/loop%d", i);
- if (stat (dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
- if ((fd = open (dev, O_RDONLY)) >= 0) {
- if(ioctl (fd, LOOP_GET_STATUS, &loopinfo) == -1 &&
- errno == ENXIO) { /* probably free */
- close (fd);
- return strdup(dev);
- }
- close (fd);
- }
- }
- }
- return NULL;
-}
-#endif /* BB_FEATURE_MOUNT_LOOP */
diff --git a/networking/ping.c b/networking/ping.c
index 92b62de..2b6e7f5 100644
--- a/networking/ping.c
+++ b/networking/ping.c
@@ -1,5 +1,5 @@
/*
- * $Id: ping.c,v 1.6 1999/12/11 08:41:28 andersen Exp $
+ * $Id: ping.c,v 1.7 2000/01/26 20:06:48 erik Exp $
* Mini ping implementation for busybox
*
* Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
@@ -319,10 +319,11 @@
int sockopt;
if (!(proto = getprotobyname("icmp"))) {
- fprintf(stderr, "ping: unknown protocol icmp\n");
- exit(1);
+ /* getprotobyname failed, so just silently force
+ * proto->p_proto to have the correct value for "icmp" */
+ proto->p_proto = 1;
}
- if ((pingsock = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0) {
+ if ((pingsock = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0) { /* 1 == ICMP */
if (errno == EPERM) {
fprintf(stderr, "ping: permission denied. (are you root?)\n");
} else {
diff --git a/ping.c b/ping.c
index 92b62de..2b6e7f5 100644
--- a/ping.c
+++ b/ping.c
@@ -1,5 +1,5 @@
/*
- * $Id: ping.c,v 1.6 1999/12/11 08:41:28 andersen Exp $
+ * $Id: ping.c,v 1.7 2000/01/26 20:06:48 erik Exp $
* Mini ping implementation for busybox
*
* Copyright (C) 1999 by Randolph Chung <tausq@debian.org>
@@ -319,10 +319,11 @@
int sockopt;
if (!(proto = getprotobyname("icmp"))) {
- fprintf(stderr, "ping: unknown protocol icmp\n");
- exit(1);
+ /* getprotobyname failed, so just silently force
+ * proto->p_proto to have the correct value for "icmp" */
+ proto->p_proto = 1;
}
- if ((pingsock = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0) {
+ if ((pingsock = socket(AF_INET, SOCK_RAW, proto->p_proto)) < 0) { /* 1 == ICMP */
if (errno == EPERM) {
fprintf(stderr, "ping: permission denied. (are you root?)\n");
} else {
diff --git a/umount.c b/umount.c
index 9ad6f26..68b27e3 100644
--- a/umount.c
+++ b/umount.c
@@ -28,14 +28,6 @@
#include <fstab.h>
#include <errno.h>
-#if defined BB_FEATURE_MOUNT_LOOP
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <linux/loop.h>
-
-static int del_loop(const char *device);
-#endif
-
static const char umount_usage[] =
"umount [flags] filesystem|directory\n\n"
"Flags:\n"
@@ -52,43 +44,34 @@
static int umountAll = FALSE;
extern const char mtab_file[]; /* Defined in utility.c */
+#define MIN(x,y) (x > y ? x : y)
+
static int
do_umount(const char* name, int useMtab)
{
int status;
+ struct mntent *m;
+ FILE *mountTable;
+ const char *blockDevice = NULL;
-#if defined BB_FEATURE_MOUNT_LOOP
- /* check to see if this is a loop device */
- struct stat fst;
- char dev[20];
- const char *oldname = NULL;
- int i;
-
- if (stat(name, &fst)) {
- fprintf(stderr, "umount: %s: %s\n", name, strerror(errno));
- exit(1);
- }
- for (i = 0 ; i <= 7 ; i++) {
- struct stat lst;
- sprintf(dev, "/dev/loop%d", i);
- if (stat(dev, &lst))
- continue;
- if (lst.st_dev == fst.st_dev) {
- oldname = name;
- name = dev;
- break;
+ if ((mountTable = setmntent (mtab_file, "r"))) {
+ while ((m = getmntent (mountTable)) != 0) {
+ if (strncmp(m->mnt_dir, name,
+ MIN(strlen(m->mnt_dir),strlen(name))) == 0)
+ blockDevice = m->mnt_fsname;
+ else if (strcmp(m->mnt_fsname, name) == 0) {
+ blockDevice = name;
+ name = m->mnt_dir;
+ }
}
}
-#endif
status = umount(name);
#if defined BB_FEATURE_MOUNT_LOOP
- if (!strncmp("/dev/loop", name, 9)) { /* this was a loop device, delete it */
- del_loop(name);
- if (oldname != NULL)
- name = oldname;
- }
+ if (blockDevice != NULL && !strncmp("/dev/loop", blockDevice, 9))
+ /* this was a loop device, delete it */
+ del_loop(blockDevice);
#endif
#if defined BB_MTAB
if ( status == 0 ) {
@@ -178,20 +161,3 @@
}
}
-#if defined BB_FEATURE_MOUNT_LOOP
-static int del_loop(const char *device)
-{
- int fd;
-
- if ((fd = open(device, O_RDONLY)) < 0) {
- perror(device);
- exit(1);
- }
- if (ioctl(fd, LOOP_CLR_FD, 0) < 0) {
- perror("ioctl: LOOP_CLR_FD");
- exit(1);
- }
- close(fd);
- return(0);
-}
-#endif
diff --git a/util-linux/mount.c b/util-linux/mount.c
index 709c7fc..3c1568a 100644
--- a/util-linux/mount.c
+++ b/util-linux/mount.c
@@ -127,11 +127,11 @@
specialfile = find_unused_loop_device();
if (specialfile == NULL) {
fprintf(stderr, "Could not find a spare loop device\n");
- exit(1);
+ return( FALSE);
}
if (set_loop (specialfile, lofile, 0, &loro)) {
fprintf(stderr, "Could not setup loop device\n");
- exit(1);
+ return( FALSE);
}
if (!(flags & MS_RDONLY) && loro) { /* loop is ro, but wanted rw */
fprintf(stderr, "WARNING: loop device is read-only\n");
@@ -141,15 +141,26 @@
#endif
status=mount(specialfile, dir, filesystemtype, flags, string_flags);
}
-#if defined BB_MTAB
+
+
+ /* If the mount was sucessful, do anything needed, then return TRUE */
if (status == 0) {
- if (useMtab==TRUE)
+
+#if defined BB_MTAB
+ if (useMtab==TRUE) {
write_mtab(specialfile, dir, filesystemtype, flags, mtab_opts);
- return 0;
- }
- else
+ }
#endif
- return(status);
+ return( TRUE);
+ }
+
+ /* Bummer. mount failed. Clean up */
+#if defined BB_FEATURE_MOUNT_LOOP
+ if (specialfile != NULL) {
+ del_loop(specialfile);
+ }
+#endif
+ return( FALSE);
}
@@ -166,6 +177,75 @@
#endif
+#if defined BB_FEATURE_MOUNT_LOOP
+static int set_loop(const char *device, const char *file, int offset, int *loopro)
+{
+ struct loop_info loopinfo;
+ int fd, ffd, mode;
+
+ mode = *loopro ? O_RDONLY : O_RDWR;
+ if ((ffd = open (file, mode)) < 0 && !*loopro
+ && (errno != EROFS || (ffd = open (file, mode = O_RDONLY)) < 0)) {
+ perror (file);
+ return 1;
+ }
+ if ((fd = open (device, mode)) < 0) {
+ close(ffd);
+ perror (device);
+ return 1;
+ }
+ *loopro = (mode == O_RDONLY);
+
+ memset(&loopinfo, 0, sizeof(loopinfo));
+ strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
+ loopinfo.lo_name[LO_NAME_SIZE-1] = 0;
+
+ loopinfo.lo_offset = offset;
+
+ loopinfo.lo_encrypt_key_size = 0;
+ if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
+ perror("ioctl: LOOP_SET_FD");
+ close(fd);
+ close(ffd);
+ return 1;
+ }
+ if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
+ (void) ioctl(fd, LOOP_CLR_FD, 0);
+ perror("ioctl: LOOP_SET_STATUS");
+ close(fd);
+ close(ffd);
+ return 1;
+ }
+ close(fd);
+ close(ffd);
+ return 0;
+}
+
+char *find_unused_loop_device (void)
+{
+ char dev[20];
+ int i, fd;
+ struct stat statbuf;
+ struct loop_info loopinfo;
+
+ for(i = 0; i <= 7; i++) {
+ sprintf(dev, "/dev/loop%d", i);
+ if (stat (dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
+ if ((fd = open (dev, O_RDONLY)) >= 0) {
+ if(ioctl (fd, LOOP_GET_STATUS, &loopinfo) == -1) {
+ if (errno == ENXIO) { /* probably free */
+ close (fd);
+ return strdup(dev);
+ }
+ }
+ close (fd);
+ }
+ }
+ }
+ return NULL;
+}
+#endif /* BB_FEATURE_MOUNT_LOOP */
+
/* Seperate standard mount options from the nonstandard string options */
static void
parse_mount_options ( char *options, unsigned long *flags, char *strflags)
@@ -240,7 +320,7 @@
status = do_mount (blockDevice, directory, filesystemType,
flags | MS_MGC_VAL, string_flags, useMtab,
fakeIt, mtab_opts);
- if (status == 0)
+ if (status == TRUE)
break;
}
}
@@ -253,7 +333,7 @@
fakeIt, mtab_opts);
}
- if (status) {
+ if (status==FALSE) {
fprintf (stderr, "Mounting %s on %s failed: %s\n",
blockDevice, directory, strerror(errno));
return (FALSE);
@@ -400,70 +480,3 @@
usage( mount_usage);
}
-#if defined BB_FEATURE_MOUNT_LOOP
-static int set_loop(const char *device, const char *file, int offset, int *loopro)
-{
- struct loop_info loopinfo;
- int fd, ffd, mode;
-
- mode = *loopro ? O_RDONLY : O_RDWR;
- if ((ffd = open (file, mode)) < 0 && !*loopro
- && (errno != EROFS || (ffd = open (file, mode = O_RDONLY)) < 0)) {
- perror (file);
- return 1;
- }
- if ((fd = open (device, mode)) < 0) {
- close(ffd);
- perror (device);
- return 1;
- }
- *loopro = (mode == O_RDONLY);
-
- memset(&loopinfo, 0, sizeof(loopinfo));
- strncpy(loopinfo.lo_name, file, LO_NAME_SIZE);
- loopinfo.lo_name[LO_NAME_SIZE-1] = 0;
-
- loopinfo.lo_offset = offset;
-
- loopinfo.lo_encrypt_key_size = 0;
- if (ioctl(fd, LOOP_SET_FD, ffd) < 0) {
- perror("ioctl: LOOP_SET_FD");
- close(fd);
- close(ffd);
- return 1;
- }
- if (ioctl(fd, LOOP_SET_STATUS, &loopinfo) < 0) {
- (void) ioctl(fd, LOOP_CLR_FD, 0);
- perror("ioctl: LOOP_SET_STATUS");
- close(fd);
- close(ffd);
- return 1;
- }
- close(fd);
- close(ffd);
- return 0;
-}
-
-char *find_unused_loop_device (void)
-{
- char dev[20];
- int i, fd;
- struct stat statbuf;
- struct loop_info loopinfo;
-
- for(i = 0; i <= 7; i++) {
- sprintf(dev, "/dev/loop%d", i);
- if (stat (dev, &statbuf) == 0 && S_ISBLK(statbuf.st_mode)) {
- if ((fd = open (dev, O_RDONLY)) >= 0) {
- if(ioctl (fd, LOOP_GET_STATUS, &loopinfo) == -1 &&
- errno == ENXIO) { /* probably free */
- close (fd);
- return strdup(dev);
- }
- close (fd);
- }
- }
- }
- return NULL;
-}
-#endif /* BB_FEATURE_MOUNT_LOOP */
diff --git a/util-linux/umount.c b/util-linux/umount.c
index 9ad6f26..68b27e3 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -28,14 +28,6 @@
#include <fstab.h>
#include <errno.h>
-#if defined BB_FEATURE_MOUNT_LOOP
-#include <fcntl.h>
-#include <sys/ioctl.h>
-#include <linux/loop.h>
-
-static int del_loop(const char *device);
-#endif
-
static const char umount_usage[] =
"umount [flags] filesystem|directory\n\n"
"Flags:\n"
@@ -52,43 +44,34 @@
static int umountAll = FALSE;
extern const char mtab_file[]; /* Defined in utility.c */
+#define MIN(x,y) (x > y ? x : y)
+
static int
do_umount(const char* name, int useMtab)
{
int status;
+ struct mntent *m;
+ FILE *mountTable;
+ const char *blockDevice = NULL;
-#if defined BB_FEATURE_MOUNT_LOOP
- /* check to see if this is a loop device */
- struct stat fst;
- char dev[20];
- const char *oldname = NULL;
- int i;
-
- if (stat(name, &fst)) {
- fprintf(stderr, "umount: %s: %s\n", name, strerror(errno));
- exit(1);
- }
- for (i = 0 ; i <= 7 ; i++) {
- struct stat lst;
- sprintf(dev, "/dev/loop%d", i);
- if (stat(dev, &lst))
- continue;
- if (lst.st_dev == fst.st_dev) {
- oldname = name;
- name = dev;
- break;
+ if ((mountTable = setmntent (mtab_file, "r"))) {
+ while ((m = getmntent (mountTable)) != 0) {
+ if (strncmp(m->mnt_dir, name,
+ MIN(strlen(m->mnt_dir),strlen(name))) == 0)
+ blockDevice = m->mnt_fsname;
+ else if (strcmp(m->mnt_fsname, name) == 0) {
+ blockDevice = name;
+ name = m->mnt_dir;
+ }
}
}
-#endif
status = umount(name);
#if defined BB_FEATURE_MOUNT_LOOP
- if (!strncmp("/dev/loop", name, 9)) { /* this was a loop device, delete it */
- del_loop(name);
- if (oldname != NULL)
- name = oldname;
- }
+ if (blockDevice != NULL && !strncmp("/dev/loop", blockDevice, 9))
+ /* this was a loop device, delete it */
+ del_loop(blockDevice);
#endif
#if defined BB_MTAB
if ( status == 0 ) {
@@ -178,20 +161,3 @@
}
}
-#if defined BB_FEATURE_MOUNT_LOOP
-static int del_loop(const char *device)
-{
- int fd;
-
- if ((fd = open(device, O_RDONLY)) < 0) {
- perror(device);
- exit(1);
- }
- if (ioctl(fd, LOOP_CLR_FD, 0) < 0) {
- perror("ioctl: LOOP_CLR_FD");
- exit(1);
- }
- close(fd);
- return(0);
-}
-#endif
diff --git a/utility.c b/utility.c
index 8139f38..643c3b5 100644
--- a/utility.c
+++ b/utility.c
@@ -36,6 +36,13 @@
#include <unistd.h>
#include <ctype.h>
+#if defined BB_FEATURE_MOUNT_LOOP
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/loop.h>
+#endif
+
+
#if defined BB_MOUNT || defined BB_UMOUNT || defined BB_DF
# if defined BB_FEATURE_USE_PROCFS
const char mtab_file[] = "/proc/mounts";
@@ -1146,4 +1153,22 @@
}
#endif
+#if defined BB_FEATURE_MOUNT_LOOP
+extern int del_loop(const char *device)
+{
+ int fd;
+
+ if ((fd = open(device, O_RDONLY)) < 0) {
+ perror(device);
+ return( FALSE);
+ }
+ if (ioctl(fd, LOOP_CLR_FD, 0) < 0) {
+ perror("ioctl: LOOP_CLR_FD");
+ return( FALSE);
+ }
+ close(fd);
+ return( TRUE);
+}
+#endif
+
/* END CODE */