btrfs-progs: move btrfslabel.[c|h] stuff to utils.[c|h]

Clean btrfslabel.[c|h] out of the source tree and move those related
functions to utils.[c|h].

CC: Gene Czarcinski <gene@czarc.net>
Signed-off-by: Jie Liu <jeff.liu@oracle.com>
Signed-off-by: David Sterba <dsterba@suse.cz>

1 files changed, 130 insertions, 0 deletions

diff --git a/utils.c b/utils.c
index 50e54532..ac3c053e 100644
--- a/utils.c
+++ b/utils.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2007 Oracle.  All rights reserved.
+ * Copyright (C) 2008 Morey Roof.  All rights reserved.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public
@@ -19,6 +20,7 @@
 #define _XOPEN_SOURCE 700
 #define __USE_XOPEN2K8
 #define __XOPEN2K8 /* due to an error in dirent.h, to get dirfd() */
+#define _GNU_SOURCE	/* O_NOATIME */
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -1164,6 +1166,134 @@ static int check_label(const char *input)
        return 0;
 }
 
+static int set_label_unmounted(const char *dev, const char *label)
+{
+	struct btrfs_trans_handle *trans;
+	struct btrfs_root *root;
+	int ret;
+
+	ret = check_mounted(dev);
+	if (ret < 0) {
+	       fprintf(stderr, "FATAL: error checking %s mount status\n", dev);
+	       return -1;
+	}
+	if (ret > 0) {
+		fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
+			dev);
+		return -1;
+	}
+
+	/* Open the super_block at the default location
+	 * and as read-write.
+	 */
+	root = open_ctree(dev, 0, 1);
+	if (!root) /* errors are printed by open_ctree() */
+		return -1;
+
+	trans = btrfs_start_transaction(root, 1);
+	snprintf(root->fs_info->super_copy.label, BTRFS_LABEL_SIZE, "%s",
+		 label);
+	btrfs_commit_transaction(trans, root);
+
+	/* Now we close it since we are done. */
+	close_ctree(root);
+	return 0;
+}
+
+static int set_label_mounted(const char *mount_path, const char *label)
+{
+	int fd;
+
+	fd = open(mount_path, O_RDONLY | O_NOATIME);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: unable access to '%s'\n", mount_path);
+		return -1;
+	}
+
+	if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) {
+		fprintf(stderr, "ERROR: unable to set label %s\n",
+			strerror(errno));
+		close(fd);
+		return -1;
+	}
+
+	return 0;
+}
+
+static int get_label_unmounted(const char *dev)
+{
+	struct btrfs_root *root;
+	int ret;
+
+	ret = check_mounted(dev);
+	if (ret < 0) {
+	       fprintf(stderr, "FATAL: error checking %s mount status\n", dev);
+	       return -1;
+	}
+	if (ret > 0) {
+		fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n",
+			dev);
+		return -1;
+	}
+
+	/* Open the super_block at the default location
+	 * and as read-only.
+	 */
+	root = open_ctree(dev, 0, 0);
+	if(!root)
+		return -1;
+
+	fprintf(stdout, "%s\n", root->fs_info->super_copy.label);
+
+	/* Now we close it since we are done. */
+	close_ctree(root);
+	return 0;
+}
+
+/*
+ * If a partition is mounted, try to get the filesystem label via its
+ * mounted path rather than device.  Return the corresponding error
+ * the user specified the device path.
+ */
+static int get_label_mounted(const char *mount_path)
+{
+	char label[BTRFS_LABEL_SIZE];
+	int fd;
+
+	fd = open(mount_path, O_RDONLY | O_NOATIME);
+	if (fd < 0) {
+		fprintf(stderr, "ERROR: unable access to '%s'\n", mount_path);
+		return -1;
+	}
+
+	memset(label, '\0', sizeof(label));
+	if (ioctl(fd, BTRFS_IOC_GET_FSLABEL, label) < 0) {
+		fprintf(stderr, "ERROR: unable get label %s\n", strerror(errno));
+		close(fd);
+		return -1;
+	}
+
+	fprintf(stdout, "%s\n", label);
+	return 0;
+}
+
+int get_label(const char *btrfs_dev)
+{
+	return is_existing_blk_or_reg_file(btrfs_dev) ?
+		get_label_unmounted(btrfs_dev) :
+		get_label_mounted(btrfs_dev);
+}
+
+int set_label(const char *btrfs_dev, const char *label)
+{
+	if (check_label(label))
+		return -1;
+
+	return is_existing_blk_or_reg_file(btrfs_dev) ?
+		set_label_unmounted(btrfs_dev, label) :
+		set_label_mounted(btrfs_dev, label);
+}
+
 int btrfs_scan_block_devices(int run_ioctl)
 {