hush/libbb/loop.c

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/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
* Copyright (C) 2005 by Rob Landley <rob@landley.net>
*
* Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
*/
#include "libbb.h"
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
/* For 2.6, use the cleaned up header to get the 64 bit API. */
#include <linux/version.h>
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0)
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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#include <linux/loop.h>
typedef struct loop_info64 bb_loop_info;
#define BB_LOOP_SET_STATUS LOOP_SET_STATUS64
#define BB_LOOP_GET_STATUS LOOP_GET_STATUS64
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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/* For 2.4 and earlier, use the 32 bit API (and don't trust the headers) */
#else
/* Stuff stolen from linux/loop.h for 2.4 and earlier kernels*/
#include <linux/posix_types.h>
#define LO_NAME_SIZE 64
#define LO_KEY_SIZE 32
#define LOOP_SET_FD 0x4C00
#define LOOP_CLR_FD 0x4C01
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
#define BB_LOOP_SET_STATUS 0x4C02
#define BB_LOOP_GET_STATUS 0x4C03
typedef struct {
int lo_number;
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
__kernel_dev_t lo_device;
unsigned long lo_inode;
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
__kernel_dev_t lo_rdevice;
int lo_offset;
int lo_encrypt_type;
int lo_encrypt_key_size;
int lo_flags;
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
char lo_file_name[LO_NAME_SIZE];
unsigned char lo_encrypt_key[LO_KEY_SIZE];
unsigned long lo_init[2];
char reserved[4];
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
} bb_loop_info;
#endif
char *query_loop(const char *device)
{
int fd;
bb_loop_info loopinfo;
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char *dev = 0;
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fd = open(device, O_RDONLY);
if (fd < 0) return 0;
if (!ioctl(fd, BB_LOOP_GET_STATUS, &loopinfo))
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dev = xasprintf("%ld %s", (long) loopinfo.lo_offset,
(char *)loopinfo.lo_file_name);
close(fd);
return dev;
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}
int del_loop(const char *device)
{
int fd, rc;
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fd = open(device, O_RDONLY);
if (fd < 0) return 1;
rc = ioctl(fd, LOOP_CLR_FD, 0);
close(fd);
2006-01-25 00:08:53 +00:00
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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return rc;
}
/* Returns 0 if mounted RW, 1 if mounted read-only, <0 for error.
*device is loop device to use, or if *device==NULL finds a loop device to
mount it on and sets *device to a strdup of that loop device name. This
search will re-use an existing loop device already bound to that
file/offset if it finds one.
*/
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int set_loop(char **device, const char *file, unsigned long long offset)
{
char dev[20], *try;
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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bb_loop_info loopinfo;
struct stat statbuf;
int i, dfd, ffd, mode, rc = -1;
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/* Open the file. Barf if this doesn't work. */
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mode = O_RDWR;
ffd = open(file, mode);
if (ffd < 0) {
mode = O_RDONLY;
ffd = open(file, mode);
if (ffd < 0)
return -errno;
}
/* Find a loop device. */
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try = *device ? : dev;
for (i = 0; rc; i++) {
sprintf(dev, LOOP_FORMAT, i);
/* Ran out of block devices, return failure. */
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if (stat(try, &statbuf) || !S_ISBLK(statbuf.st_mode)) {
rc = -ENOENT;
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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break;
}
/* Open the sucker and check its loopiness. */
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dfd = open(try, mode);
if (dfd < 0 && errno == EROFS) {
mode = O_RDONLY;
dfd = open(try, mode);
}
if (dfd < 0)
goto try_again;
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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rc = ioctl(dfd, BB_LOOP_GET_STATUS, &loopinfo);
/* If device is free, claim it. */
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if (rc && errno == ENXIO) {
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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memset(&loopinfo, 0, sizeof(loopinfo));
safe_strncpy((char *)loopinfo.lo_file_name, file, LO_NAME_SIZE);
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
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loopinfo.lo_offset = offset;
/* Associate free loop device with file. */
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if (!ioctl(dfd, LOOP_SET_FD, ffd)) {
if (!ioctl(dfd, BB_LOOP_SET_STATUS, &loopinfo))
rc = 0;
else
ioctl(dfd, LOOP_CLR_FD, 0);
}
/* If this block device already set up right, re-use it.
(Yes this is racy, but associating two loop devices with the same
file isn't pretty either. In general, mounting the same file twice
without using losetup manually is problematic.)
*/
} else if (strcmp(file, (char *)loopinfo.lo_file_name) != 0
|| offset != loopinfo.lo_offset) {
rc = -1;
}
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
close(dfd);
try_again:
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if (*device) break;
}
Major rewrite of mount, umount, losetup. Untangled lots of code, shrunk things down a bit, fixed a number of funky corner cases, added support for several new features (things like mount --move, mount --bind, lazy unounts, automatic detection of loop mounts, and so on). Probably broke several other things, but it's fixable. (Bang on it, tell me what doesn't work for you...) Note: you no longer need to say "-o loop". It does that for you when necessary. Still need to add "user mount" support, which involves making mount suid. Not too hard to do under the new infrastructure, just haven't done it yet... The previous code had the following notes, that belong in the version control comments: - * 3/21/1999 Charles P. Wright <cpwright@cpwright.com> - * searches through fstab when -a is passed - * will try mounting stuff with all fses when passed -t auto - * - * 1999-04-17 Dave Cinege...Rewrote -t auto. Fixed ro mtab. - * - * 1999-10-07 Erik Andersen <andersen@codepoet.org>. - * Rewrite of a lot of code. Removed mtab usage (I plan on - * putting it back as a compile-time option some time), - * major adjustments to option parsing, and some serious - * dieting all around. - * - * 1999-11-06 mtab support is back - andersee - * - * 2000-01-12 Ben Collins <bcollins@debian.org>, Borrowed utils-linux's - * mount to add loop support. - * - * 2000-04-30 Dave Cinege <dcinege@psychosis.com> - * Rewrote fstab while loop and lower mount section. Can now do - * single mounts from fstab. Can override fstab options for single - * mount. Common mount_one call for single mounts and 'all'. Fixed - * mtab updating and stale entries. Removed 'remount' default. - *
2005-08-10 20:35:54 +00:00
close(ffd);
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if (!rc) {
if (!*device)
*device = xstrdup(dev);
return (mode == O_RDONLY) ? 1 : 0;
2006-10-08 12:49:22 +00:00
}
return rc;
}