C++ (Cpp) btrfs_list_path_for_rootの例

コード例 #1

ファイル: libbtrfs.c プロジェクト: jkarlson/solstice

static int get_rootfd(int atfd, uint64_t root) {
	assert(rtable != NULL && rtable_size);
	if (BTRFS_FS_TREE_OBJECTID == root)
		return atfd;
	assert(MIN_SUBVOL<=root);

	uint64_t index = (root-MIN_SUBVOL)%rtable_size;
	if (rtable[index].rootid == root)
		return rtable[index].fd;
	rtable_misses++;

	char *name = btrfs_list_path_for_root(atfd, root);
	assert(name);
	if (IS_ERR(name)) {
		return -PTR_ERR(name);
	}
	int path_fd=openat(atfd,name,O_RDONLY);
	if (path_fd < 0) {
		path_fd=-errno;
	}
	free(name);

	if (0 <= path_fd) {
		if (rtable[index].rootid && close(rtable[index].fd))
			abort();
		rtable[index].fd=path_fd;
		rtable[index].rootid=root;
	}

	return path_fd;
}

コード例 #2

ファイル: cmds-inspect.c プロジェクト: devimc/btrfs-progs

static int cmd_inspect_logical_resolve(int argc, char **argv)
{
	int ret;
	int fd;
	int i;
	int verbose = 0;
	int getpath = 1;
	int bytes_left;
	struct btrfs_ioctl_logical_ino_args loi;
	struct btrfs_data_container *inodes;
	u64 size = 4096;
	char full_path[4096];
	char *path_ptr;
	DIR *dirstream = NULL;

	optind = 1;
	while (1) {
		int c = getopt(argc, argv, "Pvs:");
		if (c < 0)
			break;

		switch (c) {
		case 'P':
			getpath = 0;
			break;
		case 'v':
			verbose = 1;
			break;
		case 's':
			size = arg_strtou64(optarg);
			break;
		default:
			usage(cmd_inspect_logical_resolve_usage);
		}
	}

	if (check_argc_exact(argc - optind, 2))
		usage(cmd_inspect_logical_resolve_usage);

	size = min(size, (u64)64 * 1024);
	inodes = malloc(size);
	if (!inodes)
		return 1;

	memset(inodes, 0, sizeof(*inodes));
	loi.logical = arg_strtou64(argv[optind]);
	loi.size = size;
	loi.inodes = ptr_to_u64(inodes);

	fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
	if (fd < 0) {
		ret = 12;
		goto out;
	}

	ret = ioctl(fd, BTRFS_IOC_LOGICAL_INO, &loi);
	if (ret < 0) {
		error("logical ino ioctl: %s", strerror(errno));
		goto out;
	}

	if (verbose)
		printf("ioctl ret=%d, total_size=%llu, bytes_left=%lu, "
			"bytes_missing=%lu, cnt=%d, missed=%d\n",
			ret, size,
			(unsigned long)inodes->bytes_left,
			(unsigned long)inodes->bytes_missing,
			inodes->elem_cnt, inodes->elem_missed);

	bytes_left = sizeof(full_path);
	ret = snprintf(full_path, bytes_left, "%s/", argv[optind+1]);
	path_ptr = full_path + ret;
	bytes_left -= ret + 1;
	BUG_ON(bytes_left < 0);

	for (i = 0; i < inodes->elem_cnt; i += 3) {
		u64 inum = inodes->val[i];
		u64 offset = inodes->val[i+1];
		u64 root = inodes->val[i+2];
		int path_fd;
		char *name;
		DIR *dirs = NULL;

		if (getpath) {
			name = btrfs_list_path_for_root(fd, root);
			if (IS_ERR(name)) {
				ret = PTR_ERR(name);
				goto out;
			}
			if (!name) {
				path_ptr[-1] = '\0';
				path_fd = fd;
			} else {
				path_ptr[-1] = '/';
				ret = snprintf(path_ptr, bytes_left, "%s",
						name);
				BUG_ON(ret >= bytes_left);
				free(name);
				path_fd = btrfs_open_dir(full_path, &dirs, 1);
				if (path_fd < 0) {
					ret = -ENOENT;
					goto out;
				}
			}
			__ino_to_path_fd(inum, path_fd, verbose, full_path);
			if (path_fd != fd)
				close_file_or_dir(path_fd, dirs);
		} else {
			printf("inode %llu offset %llu root %llu\n", inum,
				offset, root);
		}
	}

out:
	close_file_or_dir(fd, dirstream);
	free(inodes);
	return !!ret;
}