btrfs-progs: image: better error handling in update_disk_super_on_device

Return an error code instead of exitting, more verbose messages.

Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/btrfs-image.c b/btrfs-image.c
index f48d81a..18ad398 100644 (file)
--- a/btrfs-image.c
+++ b/btrfs-image.c
@@ -2588,8 +2588,8 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
        char fs_uuid[BTRFS_UUID_SIZE];
        u64 devid, type, io_align, io_width;
        u64 sector_size, total_bytes, bytes_used;
-       char *buf;
-       int fp;
+       char *buf = NULL;
+       int fp = -1;
        int ret;
 
        key.objectid = BTRFS_DEV_ITEMS_OBJECTID;
@@ -2599,8 +2599,9 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
        btrfs_init_path(&path);
        ret = btrfs_search_slot(NULL, info->chunk_root, &key, &path, 0, 0); 
        if (ret) {
-               fprintf(stderr, "search key fails\n");
-               exit(1);
+               fprintf(stderr, "ERROR: search key failed\n");
+               ret = -EIO;
+               goto out;
        }
 
        leaf = path.nodes[0];
@@ -2609,8 +2610,9 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
 
        devid = btrfs_device_id(leaf, dev_item);
        if (devid != cur_devid) {
-               printk("devid %llu mismatch with %llu\n", devid, cur_devid);
-               exit(1);
+               printk("ERROR: devid %llu mismatch with %llu\n", devid, cur_devid);
+               ret = -EIO;
+               goto out;
        }
 
        type = btrfs_device_type(leaf, dev_item);
@@ -2629,8 +2631,9 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
        /* update other devices' super block */
        fp = open(other_dev, O_CREAT | O_RDWR, 0600);
        if (fp < 0) {
-               fprintf(stderr, "could not open %s\n", other_dev);
-               exit(1);
+               fprintf(stderr, "ERROR: could not open %s\n", other_dev);
+               ret = -EIO;
+               goto out;
        }
 
        buf = malloc(BTRFS_SUPER_INFO_SIZE);
@@ -2658,6 +2661,10 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
 
        ret = pwrite64(fp, buf, BTRFS_SUPER_INFO_SIZE, BTRFS_SUPER_INFO_OFFSET);
        if (ret != BTRFS_SUPER_INFO_SIZE) {
+               if (ret < 0)
+                       fprintf(stderr, "ERROR: cannot write superblock: %s\n", strerror(ret));
+               else
+                       fprintf(stderr, "ERROR: cannot write superblock\n");
                ret = -EIO;
                goto out;
        }
@@ -2666,8 +2673,9 @@ static int update_disk_super_on_device(struct btrfs_fs_info *info,
 
 out:
        free(buf);
-       close(fp);
-       return 0;
+       if (fp != -1)
+               close(fp);
+       return ret;
 }
 
 static void print_usage(int ret)