/*
FUSE: Filesystem in Userspace
Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
This program can be distributed under the terms of the GNU LGPLv2.
See the file COPYING.LIB.
*/
/** @file */
#if !defined(_FUSE_H_) && !defined(_FUSE_LOWLEVEL_H_)
#error "Never include <fuse_common.h> directly; use <fuse.h> or <fuse_lowlevel.h> instead."
#endif
#ifndef _FUSE_COMMON_H_
#define _FUSE_COMMON_H_
#include "fuse_opt.h"
#include <stdint.h>
#include <sys/types.h>
/** Major version of FUSE library interface */
#define FUSE_MAJOR_VERSION 2
/** Minor version of FUSE library interface */
#define FUSE_MINOR_VERSION 9
#define FUSE_MAKE_VERSION(maj, min) ((maj) * 10 + (min))
#define FUSE_VERSION FUSE_MAKE_VERSION(FUSE_MAJOR_VERSION, FUSE_MINOR_VERSION)
/* This interface uses 64 bit off_t */
#if _FILE_OFFSET_BITS != 64
#error Please add -D_FILE_OFFSET_BITS=64 to your compile flags!
#endif
#ifdef __cplusplus
extern "C" {
#endif
/**
* Information about open files
*
* Changed in version 2.5
*/
struct fuse_file_info {
/** Open flags. Available in open() and release() */
int flags;
/** Old file handle, don't use */
unsigned long fh_old;
/** In case of a write operation indicates if this was caused by a
writepage */
int writepage;
/** Can be filled in by open, to use direct I/O on this file.
Introduced in version 2.4 */
unsigned int direct_io : 1;
/** Can be filled in by open, to indicate, that cached file data
need not be invalidated. Introduced in version 2.4 */
unsigned int keep_cache : 1;
/** Indicates a flush operation. Set in flush operation, also
maybe set in highlevel lock operation and lowlevel release
operation. Introduced in version 2.6 */
unsigned int flush : 1;
/** Can be filled in by open, to indicate that the file is not
seekable. Introduced in version 2.8 */
unsigned int nonseekable : 1;
/* Indicates that flock locks for this file should be
released. If set, lock_owner shall contain a valid value.
May only be set in ->release(). Introduced in version
2.9 */
unsigned int flock_release : 1;
/** Padding. Do not use*/
unsigned int padding : 27;
/** File handle. May be filled in by filesystem in open().
Available in all other file operations */
uint64_t fh;
/** Lock owner id. Available in locking operations and flush */
uint64_t lock_owner;
};
/**
* Capability bits for 'fuse_conn_info.capable' and 'fuse_conn_info.want'
*
* FUSE_CAP_ASYNC_READ: filesystem supports asynchronous read requests
* FUSE_CAP_POSIX_LOCKS: filesystem supports "remote" locking
* FUSE_CAP_ATOMIC_O_TRUNC: filesystem handles the O_TRUNC open flag
* FUSE_CAP_EXPORT_SUPPORT: filesystem handles lookups of "." and ".."
* FUSE_CAP_BIG_WRITES: filesystem can handle write size larger than 4kB
* FUSE_CAP_DONT_MASK: don't apply umask to file mode on create operations
* FUSE_CAP_SPLICE_WRITE: ability to use splice() to write to the fuse device
* FUSE_CAP_SPLICE_MOVE: ability to move data to the fuse device with splice()
* FUSE_CAP_SPLICE_READ: ability to use splice() to read from the fuse device
* FUSE_CAP_IOCTL_DIR: ioctl support on directories
*/
#define FUSE_CAP_ASYNC_READ (1 << 0)
#define FUSE_CAP_POSIX_LOCKS (1 << 1)
#define FUSE_CAP_ATOMIC_O_TRUNC (1 << 3)
#define FUSE_CAP_EXPORT_SUPPORT (1 << 4)
#define FUSE_CAP_BIG_WRITES (1 << 5)
#define FUSE_CAP_DONT_MASK (1 << 6)
#define FUSE_CAP_SPLICE_WRITE (1 << 7)
#define FUSE_CAP_SPLICE_MOVE (1 << 8)
#define FUSE_CAP_SPLICE_READ (1 << 9)
#define FUSE_CAP_FLOCK_LOCKS (1 << 10)
#define FUSE_CAP_IOCTL_DIR (1 << 11)
/**
* Ioctl flags
*
* FUSE_IOCTL_COMPAT: 32bit compat ioctl on 64bit machine
* FUSE_IOCTL_UNRESTRICTED: not restricted to well-formed ioctls, retry allowed
* FUSE_IOCTL_RETRY: retry with new iovecs
* FUSE_IOCTL_DIR: is a directory
*
* FUSE_IOCTL_MAX_IOV: maximum of in_iovecs + out_iovecs
*/
#define FUSE_IOCTL_COMPAT (1 << 0)
#define FUSE_IOCTL_UNRESTRICTED (1 << 1)
#define FUSE_IOCTL_RETRY (1 << 2)
#define FUSE_IOCTL_DIR (1 << 4)
#define FUSE_IOCTL_MAX_IOV 256
/**
* Connection information, passed to the ->init() method
*
* Some of the elements are read-write, these can be changed to
* indicate the value requested by the filesystem. The requested
* value must usually be smaller than the indicated value.
*/
struct fuse_conn_info {
/**
* Major version of the protocol (read-only)
*/
unsigned proto_major;
/**
* Minor version of the protocol (read-only)
*/
unsigned proto_minor;
/**
* Is asynchronous read supported (read-write)
*/
unsigned async_read;
/**
* Maximum size of the write buffer
*/
unsigned max_write;
/**
* Maximum readahead
*/
unsigned max_readahead;
/**
* Capability flags, that the kernel supports
*/
unsigned capable;
/**
* Capability flags, that the filesystem wants to enable
*/
unsigned want;
/**
* Maximum number of backgrounded requests
*/
unsigned max_background;
/**
* Kernel congestion threshold parameter
*/
unsigned congestion_threshold;
/**
* For future use.
*/
unsigned reserved[23];
};
struct fuse_session;
struct fuse_chan;
struct fuse_pollhandle;
/**
* Create a FUSE mountpoint
*
* Returns a control file descriptor suitable for passing to
* fuse_new()
*
* @param mountpoint the mount point path
* @param args argument vector
* @return the communication channel on success, NULL on failure
*/
struct fuse_chan *fuse_mount(const char *mountpoint, struct fuse_args *args);
/**
* Umount a FUSE mountpoint
*
* @param mountpoint the mount point path
* @param ch the communication channel
*/
void fuse_unmount(const char *mountpoint, struct fuse_chan *ch);
/**
* Parse common options
*
* The following options are parsed:
*
* '-f' foreground
* '-d' '-odebug' foreground, but keep the debug option
* '-s' single threaded
* '-h' '--help' help
* '-ho' help without header
* '-ofsname=..' file system name, if not present, then set to the program
* name
*
* All parameters may be NULL
*
* @param args argument vector
* @param mountpoint the returned mountpoint, should be freed after use
* @param multithreaded set to 1 unless the '-s' option is present
* @param foreground set to 1 if one of the relevant options is present
* @return 0 on success, -1 on failure
*/
int fuse_parse_cmdline(struct fuse_args *args, char **mountpoint,
int *multithreaded, int *foreground);
/**
* Go into the background
*
* @param foreground if true, stay in the foreground
* @return 0 on success, -1 on failure
*/
int fuse_daemonize(int foreground);
/**
* Get the version of the library
*
* @return the version
*/
int fuse_version(void);
/**
* Destroy poll handle
*
* @param ph the poll handle
*/
void fuse_pollhandle_destroy(struct fuse_pollhandle *ph);
/* ----------------------------------------------------------- *
* Data buffer *
* ----------------------------------------------------------- */
/**
* Buffer flags
*/
enum fuse_buf_flags {
/**
* Buffer contains a file descriptor
*
* If this flag is set, the .fd field is valid, otherwise the
* .mem fields is valid.
*/
FUSE_BUF_IS_FD = (1 << 1),
/**
* Seek on the file descriptor
*
* If this flag is set then the .pos field is valid and is
* used to seek to the given offset before performing
* operation on file descriptor.
*/
FUSE_BUF_FD_SEEK = (1 << 2),
/**
* Retry operation on file descriptor
*
* If this flag is set then retry operation on file descriptor
* until .size bytes have been copied or an error or EOF is
* detected.
*/
FUSE_BUF_FD_RETRY = (1 << 3),
};
/**
* Buffer copy flags
*/
enum fuse_buf_copy_flags {
/**
* Don't use splice(2)
*
* Always fall back to using read and write instead of
* splice(2) to copy data from one file descriptor to another.
*
* If this flag is not set, then only fall back if splice is
* unavailable.
*/
FUSE_BUF_NO_SPLICE = (1 << 1),
/**
* Force splice
*
* Always use splice(2) to copy data from one file descriptor
* to another. If splice is not available, return -EINVAL.
*/
FUSE_BUF_FORCE_SPLICE = (1 << 2),
/**
* Try to move data with splice.
*
* If splice is used, try to move pages from the source to the
* destination instead of copying. See documentation of
* SPLICE_F_MOVE in splice(2) man page.
*/
FUSE_BUF_SPLICE_MOVE = (1 << 3),
/**
* Don't block on the pipe when copying data with splice
*
* Makes the operations on the pipe non-blocking (if the pipe
* is full or empty). See SPLICE_F_NONBLOCK in the splice(2)
* man page.
*/
FUSE_BUF_SPLICE_NONBLOCK= (1 << 4),
};
/**
* Single data buffer
*
* Generic data buffer for I/O, extended attributes, etc... Data may
* be supplied as a memory pointer or as a file descriptor
*/
struct fuse_buf {
/**
* Size of data in bytes
*/
size_t size;
/**
* Buffer flags
*/
enum fuse_buf_flags flags;
/**
* Memory pointer
*
* Used unless FUSE_BUF_IS_FD flag is set.
*/
void *mem;
/**
* File descriptor
*
* Used if FUSE_BUF_IS_FD flag is set.
*/
int fd;
/**
* File position
*
* Used if FUSE_BUF_FD_SEEK flag is set.
*/
loff_t pos;
};
/**
* Data buffer vector
*
* An array of data buffers, each containing a memory pointer or a
* file descriptor.
*
* Allocate dynamically to add more than one buffer.
*/
struct fuse_bufvec {
/**
* Number of buffers in the array
*/
size_t count;
/**
* Index of current buffer within the array
*/
size_t idx;
/**
* Current offset within the current buffer
*/
size_t off;
/**
* Array of buffers
*/
struct fuse_buf buf[1];
};
/* Initialize bufvec with a single buffer of given size */
#define FUSE_BUFVEC_INIT(size__) \
((struct fuse_bufvec) { \
/* .count= */ 1, \
/* .idx = */ 0, \
/* .off = */ 0, \
/* .buf = */ { /* [0] = */ { \
/* .size = */ (size__), \
/* .flags = */ (enum fuse_buf_flags) 0, \
/* .mem = */ NULL, \
/* .fd = */ -1, \
/* .pos = */ 0, \
} } \
} )
/**
* Get total size of data in a fuse buffer vector
*
* @param bufv buffer vector
* @return size of data
*/
size_t fuse_buf_size(const struct fuse_bufvec *bufv);
/**
* Copy data from one buffer vector to another
*
* @param dst destination buffer vector
* @param src source buffer vector
* @param flags flags controlling the copy
* @return actual number of bytes copied or -errno on error
*/
ssize_t fuse_buf_copy(struct fuse_bufvec *dst, struct fuse_bufvec *src,
enum fuse_buf_copy_flags flags);
/* ----------------------------------------------------------- *
* Signal handling *
* ----------------------------------------------------------- */
/**
* Exit session on HUP, TERM and INT signals and ignore PIPE signal
*
* Stores session in a global variable. May only be called once per
* process until fuse_remove_signal_handlers() is called.
*
* @param se the session to exit
* @return 0 on success, -1 on failure
*/
int fuse_set_signal_handlers(struct fuse_session *se);
/**
* Restore default signal handlers
*
* Resets global session. After this fuse_set_signal_handlers() may
* be called again.
*
* @param se the same session as given in fuse_set_signal_handlers()
*/
void fuse_remove_signal_handlers(struct fuse_session *se);
/* ----------------------------------------------------------- *
* Compatibility stuff *
* ----------------------------------------------------------- */
#if FUSE_USE_VERSION < 26
# ifdef __FreeBSD__
# if FUSE_USE_VERSION < 25
# error On FreeBSD API version 25 or greater must be used
# endif
# endif
# include "fuse_common_compat.h"
# undef FUSE_MINOR_VERSION
# undef fuse_main
# define fuse_unmount fuse_unmount_compat22
# if FUSE_USE_VERSION == 25
# define FUSE_MINOR_VERSION 5
# define fuse_mount fuse_mount_compat25
# elif FUSE_USE_VERSION == 24 || FUSE_USE_VERSION == 22
# define FUSE_MINOR_VERSION 4
# define fuse_mount fuse_mount_compat22
# elif FUSE_USE_VERSION == 21
# define FUSE_MINOR_VERSION 1
# define fuse_mount fuse_mount_compat22
# elif FUSE_USE_VERSION == 11
# warning Compatibility with API version 11 is deprecated
# undef FUSE_MAJOR_VERSION
# define FUSE_MAJOR_VERSION 1
# define FUSE_MINOR_VERSION 1
# define fuse_mount fuse_mount_compat1
# else
# error Compatibility with API version other than 21, 22, 24, 25 and 11 not supported
# endif
#endif
#ifdef __cplusplus
}
#endif
#endif /* _FUSE_COMMON_H_ */
