| /* vi: set sw=4 ts=4: */ |
| /* |
| * Utility routines. |
| * |
| * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| |
| #include <asm/posix_types.h> |
| #include <stdio.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <sys/ioctl.h> |
| #include "libbb.h" |
| |
| /* Grumble... The 2.6.x kernel breaks asm/posix_types.h |
| * so we get to try and cope as best we can... */ |
| #include <linux/version.h> |
| |
| #if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,0) |
| #define __bb_kernel_dev_t __kernel_old_dev_t |
| #elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0) |
| #define __bb_kernel_dev_t __kernel_dev_t |
| #else |
| #define __bb_kernel_dev_t unsigned short |
| #endif |
| |
| /* Stuff stolen from linux/loop.h */ |
| #define LO_NAME_SIZE 64 |
| #define LO_KEY_SIZE 32 |
| #define LOOP_SET_FD 0x4C00 |
| #define LOOP_CLR_FD 0x4C01 |
| #define LOOP_SET_STATUS 0x4C02 |
| #define LOOP_GET_STATUS 0x4C03 |
| struct loop_info { |
| int lo_number; |
| __bb_kernel_dev_t lo_device; |
| unsigned long lo_inode; |
| __bb_kernel_dev_t lo_rdevice; |
| int lo_offset; |
| int lo_encrypt_type; |
| int lo_encrypt_key_size; |
| int lo_flags; |
| char lo_name[LO_NAME_SIZE]; |
| unsigned char lo_encrypt_key[LO_KEY_SIZE]; |
| unsigned long lo_init[2]; |
| char reserved[4]; |
| }; |
| |
| extern int del_loop(const char *device) |
| { |
| int fd; |
| |
| if ((fd = open(device, O_RDONLY)) < 0) { |
| bb_perror_msg("%s", device); |
| return (FALSE); |
| } |
| if (ioctl(fd, LOOP_CLR_FD, 0) < 0) { |
| close(fd); |
| bb_perror_msg("ioctl: LOOP_CLR_FD"); |
| return (FALSE); |
| } |
| close(fd); |
| return (TRUE); |
| } |
| |
| extern 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)) { |
| bb_perror_msg("%s", file); |
| return 1; |
| } |
| if ((fd = open(device, mode)) < 0) { |
| close(ffd); |
| bb_perror_msg("%s", device); |
| return 1; |
| } |
| *loopro = (mode == O_RDONLY); |
| |
| memset(&loopinfo, 0, sizeof(loopinfo)); |
| safe_strncpy(loopinfo.lo_name, file, LO_NAME_SIZE); |
| |
| loopinfo.lo_offset = offset; |
| |
| loopinfo.lo_encrypt_key_size = 0; |
| if (ioctl(fd, LOOP_SET_FD, ffd) < 0) { |
| bb_perror_msg("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); |
| bb_perror_msg("ioctl: LOOP_SET_STATUS"); |
| close(fd); |
| close(ffd); |
| return 1; |
| } |
| close(fd); |
| close(ffd); |
| return 0; |
| } |
| |
| extern 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, LOOP_FORMAT, 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) != 0) { |
| if (errno == ENXIO) { /* probably free */ |
| close(fd); |
| return strdup(dev); |
| } |
| } |
| close(fd); |
| } |
| } |
| } |
| return NULL; |
| } |
| |
| |
| /* END CODE */ |
| /* |
| Local Variables: |
| c-file-style: "linux" |
| c-basic-offset: 4 |
| tab-width: 4 |
| End: |
| */ |