btrfs-progs/libbtrfsutil/btrfsutil.h

233 lines
7.5 KiB
C

/*
* Copyright (C) 2018 Facebook
*
* This file is part of libbtrfsutil.
*
* libbtrfsutil is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* libbtrfsutil is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with libbtrfsutil. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef BTRFS_UTIL_H
#define BTRFS_UTIL_H
#include <stddef.h>
#include <stdint.h>
#define BTRFS_UTIL_VERSION_MAJOR 1
#define BTRFS_UTIL_VERSION_MINOR 0
#define BTRFS_UTIL_VERSION_PATCH 0
#ifdef __cplusplus
extern "C" {
#endif
/**
* enum btrfs_util_error - libbtrfsutil error codes.
*
* All functions in libbtrfsutil that can return an error return this type and
* set errno.
*/
enum btrfs_util_error {
BTRFS_UTIL_OK,
BTRFS_UTIL_ERROR_STOP_ITERATION,
BTRFS_UTIL_ERROR_NO_MEMORY,
BTRFS_UTIL_ERROR_INVALID_ARGUMENT,
BTRFS_UTIL_ERROR_NOT_BTRFS,
BTRFS_UTIL_ERROR_NOT_SUBVOLUME,
BTRFS_UTIL_ERROR_SUBVOLUME_NOT_FOUND,
BTRFS_UTIL_ERROR_OPEN_FAILED,
BTRFS_UTIL_ERROR_RMDIR_FAILED,
BTRFS_UTIL_ERROR_UNLINK_FAILED,
BTRFS_UTIL_ERROR_STAT_FAILED,
BTRFS_UTIL_ERROR_STATFS_FAILED,
BTRFS_UTIL_ERROR_SEARCH_FAILED,
BTRFS_UTIL_ERROR_INO_LOOKUP_FAILED,
BTRFS_UTIL_ERROR_SUBVOL_GETFLAGS_FAILED,
BTRFS_UTIL_ERROR_SUBVOL_SETFLAGS_FAILED,
BTRFS_UTIL_ERROR_SUBVOL_CREATE_FAILED,
BTRFS_UTIL_ERROR_SNAP_CREATE_FAILED,
BTRFS_UTIL_ERROR_SNAP_DESTROY_FAILED,
BTRFS_UTIL_ERROR_DEFAULT_SUBVOL_FAILED,
BTRFS_UTIL_ERROR_SYNC_FAILED,
BTRFS_UTIL_ERROR_START_SYNC_FAILED,
BTRFS_UTIL_ERROR_WAIT_SYNC_FAILED,
};
/**
* btrfs_util_strerror() - Convert a libtrfsutil error code to a string
* description.
* @err: The error to convert.
*
* Return: Error description.
*/
const char *btrfs_util_strerror(enum btrfs_util_error err);
/**
* btrfs_util_sync() - Force a sync on a specific Btrfs filesystem.
* @path: Path on a Btrfs filesystem.
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_sync(const char *path);
/**
* btrfs_util_sync_fd() - See btrfs_util_sync().
*/
enum btrfs_util_error btrfs_util_sync_fd(int fd);
/**
* btrfs_util_start_sync() - Start a sync on a specific Btrfs filesystem but
* don't wait for it.
* @path: Path on a Btrfs filesystem.
* @transid: Returned transaction ID which can be waited on with
* btrfs_util_wait_sync(). This can be %NULL.
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_start_sync(const char *path,
uint64_t *transid);
/**
* btrfs_util_start_sync_fd() - See btrfs_util_start_sync().
*/
enum btrfs_util_error btrfs_util_start_sync_fd(int fd, uint64_t *transid);
/**
* btrfs_util_wait_sync() - Wait for a transaction with a given ID to sync.
* @path: Path on a Btrfs filesystem.
* @transid: Transaction ID to wait for, or zero for the current transaction.
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_wait_sync(const char *path, uint64_t transid);
/**
* btrfs_util_wait_sync_fd() - See btrfs_util_wait_sync().
*/
enum btrfs_util_error btrfs_util_wait_sync_fd(int fd, uint64_t transid);
/**
* btrfs_util_is_subvolume() - Return whether a given path is a Btrfs subvolume.
* @path: Path to check.
*
* Return: %BTRFS_UTIL_OK if @path is a Btrfs subvolume,
* %BTRFS_UTIL_ERROR_NOT_BTRFS if @path is not on a Btrfs filesystem,
* %BTRFS_UTIL_ERROR_NOT_SUBVOLUME if @path is not a subvolume, non-zero error
* code on any other failure.
*/
enum btrfs_util_error btrfs_util_is_subvolume(const char *path);
/**
* btrfs_util_is_subvolume_fd() - See btrfs_util_is_subvolume().
*/
enum btrfs_util_error btrfs_util_is_subvolume_fd(int fd);
/**
* btrfs_util_subvolume_id() - Get the ID of the subvolume containing a path.
* @path: Path on a Btrfs filesystem.
* @id_ret: Returned subvolume ID.
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_subvolume_id(const char *path,
uint64_t *id_ret);
/**
* btrfs_util_subvolume_id_fd() - See btrfs_util_subvolume_id().
*/
enum btrfs_util_error btrfs_util_subvolume_id_fd(int fd, uint64_t *id_ret);
struct btrfs_util_qgroup_inherit;
/**
* btrfs_util_create_subvolume() - Create a new subvolume.
* @path: Where to create the subvolume.
* @flags: Must be zero.
* @async_transid: If not NULL, create the subvolume asynchronously (i.e.,
* without waiting for it to commit it to disk) and return the transaction ID
* that it was created in. This transaction ID can be waited on with
* btrfs_util_wait_sync().
* @qgroup_inherit: Qgroups to inherit from, or NULL.
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_create_subvolume(const char *path, int flags,
uint64_t *async_transid,
struct btrfs_util_qgroup_inherit *qgroup_inherit);
/**
* btrfs_util_create_subvolume_fd() - Create a new subvolume given its parent
* and name.
* @parent_fd: File descriptor of the parent directory where the subvolume
* should be created.
* @name: Name of the subvolume to create.
* @flags: See btrfs_util_create_subvolume().
* @async_transid: See btrfs_util_create_subvolume().
* @qgroup_inherit: See btrfs_util_create_subvolume().
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_create_subvolume_fd(int parent_fd,
const char *name,
int flags,
uint64_t *async_transid,
struct btrfs_util_qgroup_inherit *qgroup_inherit);
/**
* btrfs_util_create_qgroup_inherit() - Create a qgroup inheritance specifier
* for btrfs_util_create_subvolume() or btrfs_util_create_snapshot().
* @flags: Must be zero.
* @ret: Returned qgroup inheritance specifier.
*
* The returned structure must be freed with
* btrfs_util_destroy_qgroup_inherit().
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_create_qgroup_inherit(int flags,
struct btrfs_util_qgroup_inherit **ret);
/**
* btrfs_util_destroy_qgroup_inherit() - Destroy a qgroup inheritance specifier
* previously created with btrfs_util_create_qgroup_inherit().
* @inherit: Specifier to destroy.
*/
void btrfs_util_destroy_qgroup_inherit(struct btrfs_util_qgroup_inherit *inherit);
/**
* btrfs_util_qgroup_inherit_add_group() - Add inheritance from a qgroup to a
* qgroup inheritance specifier.
* @inherit: Specifier to modify. May be reallocated.
* @qgroupid: ID of qgroup to inherit from.
*
* Return: %BTRFS_UTIL_OK on success, non-zero error code on failure.
*/
enum btrfs_util_error btrfs_util_qgroup_inherit_add_group(struct btrfs_util_qgroup_inherit **inherit,
uint64_t qgroupid);
/**
* btrfs_util_qgroup_inherit_get_groups() - Get the qgroups a qgroup inheritance
* specifier contains.
* @inherit: Qgroup inheritance specifier.
* @groups: Returned array of qgroup IDs.
* @n: Returned number of entries in the @groups array.
*/
void btrfs_util_qgroup_inherit_get_groups(const struct btrfs_util_qgroup_inherit *inherit,
const uint64_t **groups, size_t *n);
#ifdef __cplusplus
}
#endif
#endif /* BTRFS_UTIL_H */