/* FUSE: Filesystem in Userspace Copyright (C) 2001-2007 Miklos Szeredi 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 directly; use or instead." #endif #ifndef _FUSE_COMMON_H_ #define _FUSE_COMMON_H_ #include "fuse_opt.h" #include #include /** 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 #define FUSE_DEFAULT_MAX_PAGES_PER_REQ 32 #define FUSE_MAX_MAX_PAGES 256 #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; /** In case of a write operation indicates if this was caused by a writepage */ uint32_t writepage : 1; /** Can be filled in by open, to use direct I/O on this file. Introduced in version 2.4 */ uint32_t direct_io : 1; /** Can be filled in by open, to indicate, that cached file data need not be invalidated. Introduced in version 2.4 */ uint32_t 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 */ uint32_t flush : 1; /** Can be filled in by open, to indicate that the file is not seekable. Introduced in version 2.8 */ uint32_t 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 */ uint32_t flock_release : 1; /* Requests the kernel to cache entries returned by readdir */ uint32_t cache_readdir : 1; uint32_t auto_cache : 1; /** Padding. Do not use*/ uint32_t padding : 24; /** 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 * FUSE_CAP_CACHE_SYMLINKS: cache READLINK responses */ #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) #define FUSE_CAP_READDIR_PLUS (1 << 13) #define FUSE_CAP_READDIR_PLUS_AUTO (1 << 14) #define FUSE_CAP_ASYNC_DIO (1 << 15) #define FUSE_CAP_WRITEBACK_CACHE (1 << 16) #define FUSE_CAP_PARALLEL_DIROPS (1 << 18) #define FUSE_CAP_POSIX_ACL (1 << 19) #define FUSE_CAP_CACHE_SYMLINKS (1 << 20) #define FUSE_CAP_MAX_PAGES (1 << 21) /** * 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; /** * 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; /** * Max pages */ uint16_t max_pages; /** * For future use. */ unsigned reserved[22]; }; 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. */ off_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_ */