diff options
Diffstat (limited to 'utils.c')
| -rw-r--r-- | utils.c | 133 |
1 files changed, 117 insertions, 16 deletions
@@ -16,10 +16,12 @@ * Boston, MA 021110-1307, USA. */ -#define _XOPEN_SOURCE 600 -#define __USE_XOPEN2K +#define _XOPEN_SOURCE 700 +#define __USE_XOPEN2K8 +#define __XOPEN2K8 /* due to an error in dirent.h, to get dirfd() */ #include <stdio.h> #include <stdlib.h> +#include <string.h> #ifndef __CHECKER__ #include <sys/ioctl.h> #include <sys/mount.h> @@ -652,21 +654,22 @@ int is_loop_device (const char* device) { * the associated file (e.g. /images/my_btrfs.img) */ int resolve_loop_device(const char* loop_dev, char* loop_file, int max_len) { - int loop_fd; - int ret_ioctl; - struct loop_info loopinfo; + int ret; + FILE *f; + char fmt[20]; + char p[PATH_MAX]; + char real_loop_dev[PATH_MAX]; - if ((loop_fd = open(loop_dev, O_RDONLY)) < 0) + if (!realpath(loop_dev, real_loop_dev)) + return -errno; + snprintf(p, PATH_MAX, "/sys/block/%s/loop/backing_file", strrchr(real_loop_dev, '/')); + if (!(f = fopen(p, "r"))) return -errno; - ret_ioctl = ioctl(loop_fd, LOOP_GET_STATUS, &loopinfo); - close(loop_fd); - - if (ret_ioctl == 0) { - strncpy(loop_file, loopinfo.lo_name, max_len); - if (max_len > 0) - loop_file[max_len-1] = 0; - } else + snprintf(fmt, 20, "%%%i[^\n]", max_len-1); + ret = fscanf(f, fmt, loop_file); + fclose(f); + if (ret == EOF) return -errno; return 0; @@ -1016,8 +1019,14 @@ again: } fd = open(fullpath, O_RDONLY); if (fd < 0) { - fprintf(stderr, "failed to read %s: %s\n", fullpath, - strerror(errno)); + /* ignore the following errors: + ENXIO (device don't exists) + ENOMEDIUM (No medium found -> + like a cd tray empty) + */ + if(errno != ENXIO && errno != ENOMEDIUM) + fprintf(stderr, "failed to read %s: %s\n", + fullpath, strerror(errno)); continue; } ret = btrfs_scan_one_device(fd, fullpath, &tmp_devices, @@ -1268,3 +1277,95 @@ u64 parse_size(char *s) return strtoull(s, NULL, 10) * mult; } +int open_file_or_dir(const char *fname) +{ + int ret; + struct stat st; + DIR *dirstream; + int fd; + + ret = stat(fname, &st); + if (ret < 0) { + return -1; + } + if (S_ISDIR(st.st_mode)) { + dirstream = opendir(fname); + if (!dirstream) { + return -2; + } + fd = dirfd(dirstream); + } else { + fd = open(fname, O_RDWR); + } + if (fd < 0) { + return -3; + } + return fd; +} + +int get_device_info(int fd, u64 devid, + struct btrfs_ioctl_dev_info_args *di_args) +{ + int ret; + + di_args->devid = devid; + memset(&di_args->uuid, '\0', sizeof(di_args->uuid)); + + ret = ioctl(fd, BTRFS_IOC_DEV_INFO, di_args); + return ret ? -errno : 0; +} + +int get_fs_info(int fd, char *path, struct btrfs_ioctl_fs_info_args *fi_args, + struct btrfs_ioctl_dev_info_args **di_ret) +{ + int ret = 0; + int ndevs = 0; + int i = 1; + struct btrfs_fs_devices *fs_devices_mnt = NULL; + struct btrfs_ioctl_dev_info_args *di_args; + char mp[BTRFS_PATH_NAME_MAX + 1]; + + memset(fi_args, 0, sizeof(*fi_args)); + + ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args); + if (ret && (errno == EINVAL || errno == ENOTTY)) { + /* path is not a mounted btrfs. Try if it's a device */ + ret = check_mounted_where(fd, path, mp, sizeof(mp), + &fs_devices_mnt); + if (!ret) + return -EINVAL; + if (ret < 0) + return ret; + fi_args->num_devices = 1; + fi_args->max_id = fs_devices_mnt->latest_devid; + i = fs_devices_mnt->latest_devid; + memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE); + close(fd); + fd = open_file_or_dir(mp); + if (fd < 0) + return -errno; + } else if (ret) { + return -errno; + } + + if (!fi_args->num_devices) + return 0; + + di_args = *di_ret = malloc(fi_args->num_devices * sizeof(*di_args)); + if (!di_args) + return -errno; + + for (; i <= fi_args->max_id; ++i) { + BUG_ON(ndevs >= fi_args->num_devices); + ret = get_device_info(fd, i, &di_args[ndevs]); + if (ret == -ENODEV) + continue; + if (ret) + return ret; + ndevs++; + } + + BUG_ON(ndevs == 0); + + return 0; +} |