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Diffstat (limited to '')
| -rw-r--r-- | fuse/include/fuse_common.h | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/fuse/include/fuse_common.h b/fuse/include/fuse_common.h new file mode 100644 index 000000000..f08778bd1 --- /dev/null +++ b/fuse/include/fuse_common.h @@ -0,0 +1,505 @@ +/* + 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_ */ |