74 lines
1.5 KiB
C
74 lines
1.5 KiB
C
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#include <sys/mount.h>
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#include <sys/stat.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <string.h>
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#include <unistd.h>
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#include <linux/loop.h>
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// FIXME - only one loop mount is supported at a time
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#define LOOP_DEVICE "/dev/block/loop0"
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static int is_loop_mount(const char* path)
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{
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FILE* f;
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int count;
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char device[256];
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char mount_path[256];
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char rest[256];
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int result = 0;
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int path_length = strlen(path);
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f = fopen("/proc/mounts", "r");
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if (!f) {
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fprintf(stdout, "could not open /proc/mounts\n");
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return -1;
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}
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do {
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count = fscanf(f, "%255s %255s %255s\n", device, mount_path, rest);
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if (count == 3) {
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if (strcmp(LOOP_DEVICE, device) == 0 && strcmp(path, mount_path) == 0) {
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result = 1;
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break;
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}
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}
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} while (count == 3);
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fclose(f);
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return result;
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}
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int umount_main(int argc, char *argv[])
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{
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int loop, loop_fd;
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if(argc != 2) {
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fprintf(stderr,"umount <path>\n");
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return 1;
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}
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loop = is_loop_mount(argv[1]);
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if(umount(argv[1])){
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fprintf(stderr,"failed.\n");
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return 1;
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}
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if (loop) {
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// free the loop device
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loop_fd = open(LOOP_DEVICE, O_RDONLY);
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if (loop_fd < -1) {
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perror("open loop device failed");
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return 1;
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}
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if (ioctl(loop_fd, LOOP_CLR_FD, 0) < 0) {
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perror("ioctl LOOP_CLR_FD failed");
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return 1;
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}
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close(loop_fd);
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}
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return 0;
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}
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