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- Committer: James Westby
- Date: 2008-05-16 12:57:40 UTC
- Revision ID: jw+debian@jameswestby.net-20080516125740-fn2iqsxtfd3olmib
Tags: upstream-debian-2.2.1
Import upstream from fuse_2.2.1.orig.tar.gz
- files added:
- doc
- example
- include
- include/old
- kernel
- kernel/compat
- lib
- util
added
removed
include/fuse.h
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/*
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FUSE: Filesystem in Userspace
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Copyright (C) 2001-2005 Miklos Szeredi <miklos@szeredi.hu>
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This program can be distributed under the terms of the GNU LGPL.
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See the file COPYING.LIB.
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*/
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#ifndef _FUSE_H_
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#define _FUSE_H_
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/* This file defines the library interface of FUSE */
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/* IMPORTANT: you should define FUSE_USE_VERSION before including this
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header. To use the new API define it to 22 (recommended for any
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new application), to use the old API define it to 21 (this is the
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default), to use the even older 1.X API define it to 11. */
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#ifndef FUSE_USE_VERSION
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#define FUSE_USE_VERSION 21
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#endif
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/** Major version of FUSE library interface */
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#define FUSE_MAJOR_VERSION 2
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/** Minor version of FUSE library interface */
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#define FUSE_MINOR_VERSION 2
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/* This interface uses 64 bit off_t */
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#if _FILE_OFFSET_BITS != 64
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#error Please add -D_FILE_OFFSET_BITS=64 to your compile flags!
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#endif
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <sys/statfs.h>
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#include <utime.h>
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#ifdef __cplusplus
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extern "C" {
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#endif
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/* ----------------------------------------------------------- *
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* Basic FUSE API *
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* ----------------------------------------------------------- */
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/** Handle for a FUSE filesystem */
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struct fuse;
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/** Handle for a getdir() operation */
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typedef struct fuse_dirhandle *fuse_dirh_t;
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/** Function to add an entry in a getdir() operation
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*
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* @param h the handle passed to the getdir() operation
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* @param name the file name of the directory entry
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* @param type the file type (0 if unknown) see <dirent.h>
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* @param ino the inode number, ignored if "use_ino" mount option is
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* not specified
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* @return 0 on success, -errno on error
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*/
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typedef int (*fuse_dirfil_t) (fuse_dirh_t h, const char *name, int type,
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ino_t ino);
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/** Information about open files */
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struct fuse_file_info {
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/** Open flags. Available in open() and release() */
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int flags;
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/** File handle. May be filled in by filesystem in open().
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Available in all other file operations */
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unsigned long fh;
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/** In case of a write operation indicates if this was caused by a
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writepage */
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int writepage;
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};
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/**
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* The file system operations:
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*
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* Most of these should work very similarly to the well known UNIX
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* file system operations. A major exception is that instead of
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* returning an error in 'errno', the operation should return the
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* negated error value (-errno) directly.
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*
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* All methods are optional, but some are essential for a useful
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* filesystem (e.g. getattr). Flush, release and fsync are special
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* purpose methods, without which a full featured filesystem can still
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* be implemented.
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*/
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struct fuse_operations {
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/** Get file attributes.
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*
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* Similar to stat(). The 'st_dev' and 'st_blksize' fields are
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* ignored. The 'st_ino' field is ignored except if the 'use_ino'
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* mount option is given.
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*/
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int (*getattr) (const char *, struct stat *);
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/** Read the target of a symbolic link
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*
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* The buffer should be filled with a null terminated string. The
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* buffer size argument includes the space for the terminating
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* null character. If the linkname is too long to fit in the
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* buffer, it should be truncated. The return value should be 0
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* for success.
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*/
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int (*readlink) (const char *, char *, size_t);
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/** Read the contents of a directory
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*
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* This operation is the opendir(), readdir(), ..., closedir()
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* sequence in one call. For each directory entry the filldir
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* function should be called.
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*/
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int (*getdir) (const char *, fuse_dirh_t, fuse_dirfil_t);
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/** Create a file node
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*
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* There is no create() operation, mknod() will be called for
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* creation of all non-directory, non-symlink nodes.
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*/
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int (*mknod) (const char *, mode_t, dev_t);
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/** Create a directory */
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int (*mkdir) (const char *, mode_t);
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/** Remove a file */
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int (*unlink) (const char *);
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/** Remove a directory */
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int (*rmdir) (const char *);
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/** Create a symbolic link */
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int (*symlink) (const char *, const char *);
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/** Rename a file */
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int (*rename) (const char *, const char *);
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/** Create a hard link to a file */
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int (*link) (const char *, const char *);
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/** Change the permission bits of a file */
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int (*chmod) (const char *, mode_t);
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/** Change the owner and group of a file */
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int (*chown) (const char *, uid_t, gid_t);
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/** Change the size of a file */
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int (*truncate) (const char *, off_t);
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/** Change the access and/or modification times of a file */
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int (*utime) (const char *, struct utimbuf *);
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/** File open operation
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*
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* No creation, or trunctation flags (O_CREAT, O_EXCL, O_TRUNC)
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* will be passed to open(). Open should check if the operation
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* is permitted for the given flags. Optionally open may also
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* return an arbitary filehandle in the fuse_file_info structure,
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* which will be passed to all file operations.
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*/
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int (*open) (const char *, struct fuse_file_info *);
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/** Read data from an open file
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*
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* Read should return exactly the number of bytes requested except
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* on EOF or error, otherwise the rest of the data will be
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* substituted with zeroes. An exception to this is when the
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* 'direct_io' mount option is specified, in which case the return
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* value of the read system call will reflect the return value of
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* this operation.
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*/
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int (*read) (const char *, char *, size_t, off_t, struct fuse_file_info *);
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/** Write data to an open file
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*
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* Write should return exactly the number of bytes requested
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* except on error. An exception to this is when the 'direct_io'
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* mount option is specified (see read operation).
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*/
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int (*write) (const char *, const char *, size_t, off_t,
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struct fuse_file_info *);
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/** Get file system statistics
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*
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* The 'f_type' and 'f_fsid' fields are ignored
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*/
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int (*statfs) (const char *, struct statfs *);
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/** Possibly flush cached data
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*
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* BIG NOTE: This is not equivalent to fsync(). It's not a
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* request to sync dirty data.
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*
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* Flush is called on each close() of a file descriptor. So if a
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* filesystem wants to return write errors in close() and the file
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* has cached dirty data, this is a good place to write back data
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* and return any errors. Since many applications ignore close()
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* errors this is not always useful.
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*
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* NOTE: The flush() method may be called more than once for each
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* open(). This happens if more than one file descriptor refers
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* to an opened file due to dup(), dup2() or fork() calls. It is
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* not possible to determine if a flush is final, so each flush
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* should be treated equally. Multiple write-flush sequences are
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* relatively rare, so this shouldn't be a problem.
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*/
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int (*flush) (const char *, struct fuse_file_info *);
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/** Release an open file
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*
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* Release is called when there are no more references to an open
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* file: all file descriptors are closed and all memory mappings
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* are unmapped.
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*
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* For every open() call there will be exactly one release() call
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* with the same flags and file descriptor. It is possible to
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* have a file opened more than once, in which case only the last
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* release will mean, that no more reads/writes will happen on the
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* file. The return value of release is ignored.
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*/
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int (*release) (const char *, struct fuse_file_info *);
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/** Synchronize file contents
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*
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* If the datasync parameter is non-zero, then only the user data
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* should be flushed, not the meta data.
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*/
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int (*fsync) (const char *, int, struct fuse_file_info *);
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/** Set extended attributes */
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int (*setxattr) (const char *, const char *, const char *, size_t, int);
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/** Get extended attributes */
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int (*getxattr) (const char *, const char *, char *, size_t);
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/** List extended attributes */
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int (*listxattr) (const char *, char *, size_t);
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/** Remove extended attributes */
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int (*removexattr) (const char *, const char *);
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};
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/** Extra context that may be needed by some filesystems
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*
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* The uid, gid and pid fields are not filled in case of a writepage
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* operation.
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*/
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struct fuse_context {
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/** Pointer to the fuse object */
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struct fuse *fuse;
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/** User ID of the calling process */
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uid_t uid;
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/** Group ID of the calling process */
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gid_t gid;
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/** Thread ID of the calling process */
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pid_t pid;
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/** Currently unused */
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void *private_data;
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};
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/*
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* Main function of FUSE.
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*
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* This is for the lazy. This is all that has to be called from the
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* main() function.
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*
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* This function does the following:
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* - parses command line options (-d -s and -h)
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* - passes relevant mount options to the fuse_mount()
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* - installs signal handlers for INT, HUP, TERM and PIPE
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* - registers an exit handler to unmount the filesystem on program exit
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* - creates a fuse handle
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* - registers the operations
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* - calls either the single-threaded or the multi-threaded event loop
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*
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* Note: this is currently implemented as a macro.
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*
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* @param argc the argument counter passed to the main() function
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* @param argv the argument vector passed to the main() function
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* @param op the file system operation
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* @return 0 on success, nonzero on failure
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*/
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/*
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int fuse_main(int argc, char *argv[], const struct fuse_operations *op);
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*/
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#define fuse_main(argc, argv, op) \
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fuse_main_real(argc, argv, op, sizeof(*(op)))
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/* ----------------------------------------------------------- *
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* More detailed API *
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* ----------------------------------------------------------- */
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/*
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* Create a FUSE mountpoint
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*
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* Returns a control file descriptor suitable for passing to
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* fuse_new()
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*
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* @param mountpoint the mount point path
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* @param opts a comma separated list of mount options. Can be NULL.
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* @return the control file descriptor on success, -1 on failure
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*/
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int fuse_mount(const char *mountpoint, const char *opts);
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/*
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* Umount a FUSE mountpoint
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*
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* @param mountpoint the mount point path
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*/
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void fuse_unmount(const char *mountpoint);
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/**
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* Create a new FUSE filesystem.
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*
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* @param fd the control file descriptor
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* @param opts mount options to be used by the library
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* @param op the operations
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* @param op_size the size of the fuse_operations structure
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* @return the created FUSE handle
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*/
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struct fuse *fuse_new(int fd, const char *opts,
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const struct fuse_operations *op, size_t op_size);
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/**
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* Destroy the FUSE handle.
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*
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* The filesystem is not unmounted.
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*
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* @param f the FUSE handle
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*/
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void fuse_destroy(struct fuse *f);
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/**
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* FUSE event loop.
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*
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* Requests from the kernel are processed, and the apropriate
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* operations are called.
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*
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* @param f the FUSE handle
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* @return 0 if no error occured, -1 otherwise
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*/
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int fuse_loop(struct fuse *f);
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/**
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* Exit from event loop
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*
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* @param f the FUSE handle
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*/
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void fuse_exit(struct fuse *f);
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/**
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* FUSE event loop with multiple threads
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*
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* Requests from the kernel are processed, and the apropriate
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* operations are called. Request are processed in parallel by
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* distributing them between multiple threads.
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*
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* Calling this function requires the pthreads library to be linked to
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* the application.
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*
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* @param f the FUSE handle
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* @return 0 if no error occured, -1 otherwise
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*/
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int fuse_loop_mt(struct fuse *f);
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/**
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* Get the current context
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*
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* The context is only valid for the duration of a filesystem
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* operation, and thus must not be stored and used later.
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*
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* @param f the FUSE handle
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* @return the context
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*/
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struct fuse_context *fuse_get_context(void);
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/**
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* Invalidate cached data of a file.
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*
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* Useful if the 'kernel_cache' mount option is given, since in that
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* case the cache is not invalidated on file open.
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*
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* @return 0 on success or -errno on failure
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*/
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int fuse_invalidate(struct fuse *f, const char *path);
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/**
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* Check whether a mount option should be passed to the kernel or the
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* library
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*
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* @param opt the option to check
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* @return 1 if it is a library option, 0 otherwise
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*/
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int fuse_is_lib_option(const char *opt);
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/**
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* The real main function
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*
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* Do not call this directly, use fuse_main()
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*/
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int fuse_main_real(int argc, char *argv[], const struct fuse_operations *op,
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size_t op_size);
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/* ----------------------------------------------------------- *
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* Advanced API for event handling, don't worry about this... *
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* ----------------------------------------------------------- */
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/** Structure containing a raw command */
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struct fuse_cmd;
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/** Function type used to process commands */
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typedef void (*fuse_processor_t)(struct fuse *, struct fuse_cmd *, void *);
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/** This is the part of fuse_main() before the event loop */
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struct fuse *fuse_setup(int argc, char *argv[],
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const struct fuse_operations *op, size_t op_size,
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char **mountpoint, int *multithreaded, int *fd);
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/** This is the part of fuse_main() after the event loop */
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void fuse_teardown(struct fuse *fuse, int fd, char *mountpoint);
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/** Read a single command. If none are read, return NULL */
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struct fuse_cmd *fuse_read_cmd(struct fuse *f);
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/** Process a single command */
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void fuse_process_cmd(struct fuse *f, struct fuse_cmd *cmd);
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/** Multi threaded event loop, which calls the custom command
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processor function */
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int fuse_loop_mt_proc(struct fuse *f, fuse_processor_t proc, void *data);
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/** Return the exited flag, which indicates if fuse_exit() has been
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called */
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int fuse_exited(struct fuse* f);
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/** Set function which can be used to get the current context */
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void fuse_set_getcontext_func(struct fuse_context *(*func)(void));
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/* ----------------------------------------------------------- *
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* Compatibility stuff *
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* ----------------------------------------------------------- */
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#if FUSE_USE_VERSION == 21 || FUSE_USE_VERSION == 11
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# include "fuse_compat.h"
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# define fuse_dirfil_t fuse_dirfil_t_compat
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# define __fuse_read_cmd fuse_read_cmd
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# define __fuse_process_cmd fuse_process_cmd
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# define __fuse_loop_mt fuse_loop_mt_proc
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# undef fuse_main
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# undef FUSE_MINOR_VERSION
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# undef FUSE_MAJOR_VERSION
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# if FUSE_USE_VERSION == 21
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# define FUSE_MAJOR_VERSION 2
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# define FUSE_MINOR_VERSION 1
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# define fuse_operations fuse_operations_compat2
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# define fuse_main fuse_main_compat2
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# define fuse_new fuse_new_compat2
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# define __fuse_setup fuse_setup_compat2
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# define __fuse_teardown fuse_teardown
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# define __fuse_exited fuse_exited
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# define __fuse_set_getcontext_func fuse_set_getcontext_func
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# else
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# define FUSE_MAJOR_VERSION 1
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# define FUSE_MINOR_VERSION 1
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# define fuse_statfs fuse_statfs_compat1
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# define fuse_operations fuse_operations_compat1
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# define fuse_main fuse_main_compat1
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# define fuse_new fuse_new_compat1
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# define fuse_mount fuse_mount_compat1
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# define FUSE_DEBUG FUSE_DEBUG_COMPAT1
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# endif
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#elif FUSE_USE_VERSION < 22
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# error Compatibility with API version other than 21 and 11 not supported
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#endif
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#ifdef __cplusplus
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}
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#endif
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#endif /* _FUSE_H_ */
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