libbtrfsutil: add btrfs_util_[gs]et_read_only()

[platform/upstream/btrfs-progs.git] / utils.c

diff --git a/utils.c b/utils.c
index 4a16413..f867e5a 100644 (file)
--- a/utils.c
+++ b/utils.c
@@ -298,7 +298,7 @@ static int btrfs_wipe_existing_sb(int fd)
        memset(buf, 0, len);
        ret = pwrite(fd, buf, len, offset);
        if (ret < 0) {
-               error("cannot wipe existing superblock: %s", strerror(errno));
+               error("cannot wipe existing superblock: %m");
                ret = -1;
        } else if (ret != len) {
                error("cannot wipe existing superblock: wrote %d of %zd", ret, len);
@@ -320,7 +320,7 @@ int btrfs_prepare_device(int fd, const char *file, u64 *block_count_ret,
 
        ret = fstat(fd, &st);
        if (ret < 0) {
-               error("unable to stat %s: %s", file, strerror(errno));
+               error("unable to stat %s: %m", file);
                return 1;
        }
 
@@ -534,7 +534,7 @@ int get_btrfs_mount(const char *dev, char *mp, size_t mp_size)
        fd = open(dev, O_RDONLY);
        if (fd < 0) {
                ret = -errno;
-               error("cannot open %s: %s", dev, strerror(errno));
+               error("cannot open %s: %m", dev);
                goto out;
        }
 
@@ -572,8 +572,8 @@ int open_path_or_dev_mnt(const char *path, DIR **dirstream, int verbose)
                        return -1;
                }
                ret = open_file_or_dir(mp, dirstream);
-               error_on(verbose && ret < 0, "can't access '%s': %s",
-                        path, strerror(errno));
+               error_on(verbose && ret < 0, "can't access '%s': %m",
+                        path);
        } else {
                ret = btrfs_open_dir(path, dirstream, 1);
        }
@@ -593,8 +593,7 @@ int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
        int ret;
 
        if (statfs(path, &stfs) != 0) {
-               error_on(verbose, "cannot access '%s': %s", path,
-                               strerror(errno));
+               error_on(verbose, "cannot access '%s': %m", path);
                return -1;
        }
 
@@ -604,8 +603,7 @@ int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
        }
 
        if (stat(path, &st) != 0) {
-               error_on(verbose, "cannot access '%s': %s", path,
-                               strerror(errno));
+               error_on(verbose, "cannot access '%s': %m", path);
                return -1;
        }
 
@@ -616,8 +614,7 @@ int btrfs_open(const char *path, DIR **dirstream, int verbose, int dir_only)
 
        ret = open_file_or_dir(path, dirstream);
        if (ret < 0) {
-               error_on(verbose, "cannot access '%s': %s", path,
-                               strerror(errno));
+               error_on(verbose, "cannot access '%s': %m", path);
        }
 
        return ret;
@@ -898,8 +895,7 @@ int check_mounted(const char* file)
 
        fd = open(file, O_RDONLY);
        if (fd < 0) {
-               error("mount check: cannot open %s: %s", file,
-                               strerror(errno));
+               error("mount check: cannot open %s: %m", file);
                return -errno;
        }
 
@@ -988,16 +984,14 @@ int btrfs_register_one_device(const char *fname)
        fd = open("/dev/btrfs-control", O_RDWR);
        if (fd < 0) {
                warning(
-       "failed to open /dev/btrfs-control, skipping device registration: %s",
-                       strerror(errno));
+       "failed to open /dev/btrfs-control, skipping device registration: %m");
                return -errno;
        }
        memset(&args, 0, sizeof(args));
        strncpy_null(args.name, fname);
        ret = ioctl(fd, BTRFS_IOC_SCAN_DEV, &args);
        if (ret < 0) {
-               error("device scan failed on '%s': %s", fname,
-                               strerror(errno));
+               error("device scan failed on '%s': %m", fname);
                ret = -errno;
        }
        close(fd);
@@ -1267,15 +1261,14 @@ static int set_label_mounted(const char *mount_path, const char *labelp)
 
        fd = open(mount_path, O_RDONLY | O_NOATIME);
        if (fd < 0) {
-               error("unable to access %s: %s", mount_path, strerror(errno));
+               error("unable to access %s: %m", mount_path);
                return -1;
        }
 
        memset(label, 0, sizeof(label));
        __strncpy_null(label, labelp, BTRFS_LABEL_SIZE - 1);
        if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
-               error("unable to set label of %s: %s", mount_path,
-                               strerror(errno));
+               error("unable to set label of %s: %m", mount_path);
                close(fd);
                return -1;
        }
@@ -1323,7 +1316,7 @@ int get_label_mounted(const char *mount_path, char *labelp)
 
        fd = open(mount_path, O_RDONLY | O_NOATIME);
        if (fd < 0) {
-               error("unable to access %s: %s", mount_path, strerror(errno));
+               error("unable to access %s: %m", mount_path);
                return -1;
        }
 
@@ -1331,8 +1324,7 @@ int get_label_mounted(const char *mount_path, char *labelp)
        ret = ioctl(fd, BTRFS_IOC_GET_FSLABEL, label);
        if (ret < 0) {
                if (errno != ENOTTY)
-                       error("unable to get label of %s: %s", mount_path,
-                                       strerror(errno));
+                       error("unable to get label of %s: %m", mount_path);
                ret = -errno;
                close(fd);
                return ret;
@@ -1549,10 +1541,16 @@ int open_file_or_dir(const char *fname, DIR **dirstream)
 
 void close_file_or_dir(int fd, DIR *dirstream)
 {
-       if (dirstream)
+       int old_errno;
+
+       old_errno = errno;
+       if (dirstream) {
                closedir(dirstream);
-       else if (fd >= 0)
+       } else if (fd >= 0) {
                close(fd);
+       }
+
+       errno = old_errno;
 }
 
 int get_device_info(int fd, u64 devid,
@@ -1670,7 +1668,7 @@ int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
                fd = open(path, O_RDONLY);
                if (fd < 0) {
                        ret = -errno;
-                       error("cannot open %s: %s", path, strerror(errno));
+                       error("cannot open %s: %m", path);
                        goto out;
                }
                ret = check_mounted_where(fd, path, mp, sizeof(mp),
@@ -1990,7 +1988,7 @@ int btrfs_scan_devices(void)
 
                fd = open(path, O_RDONLY);
                if (fd < 0) {
-                       error("cannot open %s: %s", path, strerror(errno));
+                       error("cannot open %s: %m", path);
                        continue;
                }
                ret = btrfs_scan_one_device(fd, path, &tmp_devices,
@@ -2486,6 +2484,11 @@ const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
        if (!len)
                return full_path;
 
+       if ((strncmp(mnt, full_path, len) != 0) || (full_path[len] != '/')) {
+               error("not on mount point: %s", mnt);
+               exit(1);
+       }
+
        if (mnt[len - 1] != '/')
                len += 1;