diff options
| -rw-r--r-- | src/disk.c | 58 |
1 files changed, 38 insertions, 20 deletions
@@ -51,6 +51,7 @@ int disk_open_dev(int maj, int min, int partition, int readonly) { DIR * dir; struct dirent * dirent; int found; + int old_errno; size_t len; char blkdev[1024]; @@ -117,6 +118,19 @@ int disk_open_dev(int maj, int min, int partition, int readonly) { blkdev[len] = 0; + fd = open(blkdev, (readonly ? O_RDONLY : O_RDWR) | O_EXCL); + if ( fd < 0 ) { + if ( errno != ENOMEDIUM ) + ERROR_INFO("Cannot open block device %s", blkdev); + return -1; + } else { + if ( fstat(fd, &st) != 0 || ! S_ISBLK(st.st_mode) || makedev(maj, min) != st.st_rdev ) { + ERROR("Block device %s does not have id %d:%d\n", blkdev, maj, min); + close(fd); + return -1; + } + } + } else if ( partition > 0 ) { /* Select partition */ @@ -131,37 +145,41 @@ int disk_open_dev(int maj, int min, int partition, int readonly) { ERROR("Block device name is too long"); return -1; } - if ( stat(blkdev, &st) != 0 || ! S_ISBLK(st.st_mode) ) { + fd = open(blkdev, (readonly ? O_RDONLY : O_RDWR) | O_EXCL); + if ( fd < 0 && errno == ENOENT ) { if ( snprintf(blkdev+len, sizeof(blkdev)-len, "%d", partition) >= (int)(sizeof(blkdev)-len) ) { ERROR("Block device name is too long"); return -1; } - if ( stat(blkdev, &st) != 0 || ! S_ISBLK(st.st_mode) ) { - blkdev[len] = 0; - fd = open(blkdev, O_RDONLY); - if ( fd < 0 ) { - if ( errno != ENOMEDIUM ) { - ERROR_INFO("Cannot open block device %s", blkdev); - return -1; - } - } else { - close(fd); - ERROR("Block device does not have partitions"); - return -1; - } + fd = open(blkdev, (readonly ? O_RDONLY : O_RDWR) | O_EXCL); + } + if ( fd < 0 && errno == ENOENT ) { + blkdev[len] = 0; + fd = open(blkdev, O_RDONLY); + if ( fd < 0 ) { + if ( errno != ENOMEDIUM ) + ERROR_INFO("Cannot open block device %s", blkdev); + } else { + close(fd); + ERROR("Block device %s does not have partitions", blkdev); } + return -1; } + if ( fd < 0 ) + old_errno = errno; printf("Found block device %s for partition %d\n", blkdev, partition); - } + if ( fd < 0 ) { + errno = old_errno; + ERROR_INFO("Cannot open block device %s", blkdev); + } - fd = open(blkdev, (readonly ? O_RDONLY : O_RDWR) | O_EXCL); + } else { + + ERROR("Invalid partition %d for block device %s", partition, blkdev); + fd = -1; - if ( fd < 0 ) { - if ( errno != ENOMEDIUM ) - ERROR_INFO("Cannot open block device %s", blkdev); - return -1; } return fd; |