| /* |
| FUSE: Filesystem in Userspace |
| Copyright (C) 2001-2004 Miklos Szeredi <miklos@szeredi.hu> |
| |
| This program can be distributed under the terms of the GNU LGPL. |
| See the file COPYING.LIB. |
| */ |
| |
| #ifndef _FUSE_H_ |
| #define _FUSE_H_ |
| |
| /* This file defines the library interface of FUSE */ |
| |
| /** Major version of FUSE library interface */ |
| #define FUSE_MAJOR_VERSION 2 |
| |
| /** Minor version of FUSE library interface */ |
| #define FUSE_MINOR_VERSION 0 |
| |
| /* 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 |
| |
| #include <sys/types.h> |
| #include <sys/stat.h> |
| #include <sys/statfs.h> |
| #include <utime.h> |
| |
| /* ----------------------------------------------------------- * |
| * Basic FUSE API * |
| * ----------------------------------------------------------- */ |
| |
| /** Handle for a FUSE filesystem */ |
| struct fuse; |
| |
| /** Handle for a getdir() operation */ |
| typedef struct fuse_dirhandle *fuse_dirh_t; |
| |
| /** Function to add an entry in a getdir() operation |
| * |
| * @param h the handle passed to the getdir() operation |
| * @param name the file name of the directory entry |
| * @param type the file type (0 if unknown) see <dirent.h> |
| * @return 0 on success, -errno on error |
| */ |
| typedef int (*fuse_dirfil_t) (fuse_dirh_t h, const char *name, int type); |
| |
| /** |
| * The file system operations: |
| * |
| * Most of these should work very similarly to the well known UNIX |
| * file system operations. Exceptions are: |
| * |
| * - All operations should return the negated error value (-errno) on |
| * error. |
| * |
| * - Getattr() doesn't need to fill in the following fields: |
| * st_ino |
| * st_dev |
| * st_blksize |
| * |
| * - readlink() should fill the buffer with a null terminated string. The |
| * buffer size argument includes the space for the terminating null |
| * character. If the linkname is too long to fit in the buffer, it should |
| * be truncated. The return value should be 0 for success. |
| * |
| * - getdir() is the opendir(), readdir(), ..., closedir() sequence |
| * in one call. For each directory entry the filldir parameter should |
| * be called. |
| * |
| * - There is no create() operation, mknod() will be called for |
| * creation of all non directory, non symlink nodes. |
| * |
| * - open() should not return a filehandle, but 0 on success. No |
| * creation, or trunctation flags (O_CREAT, O_EXCL, O_TRUNC) will be |
| * passed to open(). Open should only check if the operation is |
| * permitted for the given flags. |
| * |
| * - read(), write() are not passed a filehandle, but rather a |
| * pathname. The offset of the read and write is passed as the last |
| * argument, like the pread() and pwrite() system calls. (NOTE: |
| * read() should always return the number of bytes requested, except |
| * at end of file) |
| * |
| * - release() is called when an open file has: |
| * 1) all file descriptors closed |
| * 2) all memory mappings unmapped |
| * For every open() call there will be exactly one release() call |
| * with the same flags. It is possible to have a file opened more |
| * than once, in which case only the last release will mean, that no |
| * more reads/writes will happen on the file. The return value of |
| * release is ignored. Implementing this method is optional. |
| * |
| * - flush() is called when close() has been called on an open file. |
| * NOTE: this does not mean that the file is released (e.g. after |
| * fork() an open file will have two references which both must be |
| * closed before the file is released). The flush() method may be |
| * called more than once for each open(). The return value of |
| * flush() is passed on to the close() system call. Implementing |
| * this method is optional. |
| * |
| * - fsync() has a boolean 'datasync' parameter which if TRUE then do |
| * an fdatasync() operation. Implementing this method is optional. |
| */ |
| struct fuse_operations { |
| int (*getattr) (const char *, struct stat *); |
| int (*readlink) (const char *, char *, size_t); |
| int (*getdir) (const char *, fuse_dirh_t, fuse_dirfil_t); |
| int (*mknod) (const char *, mode_t, dev_t); |
| int (*mkdir) (const char *, mode_t); |
| int (*unlink) (const char *); |
| int (*rmdir) (const char *); |
| int (*symlink) (const char *, const char *); |
| int (*rename) (const char *, const char *); |
| int (*link) (const char *, const char *); |
| int (*chmod) (const char *, mode_t); |
| int (*chown) (const char *, uid_t, gid_t); |
| int (*truncate) (const char *, off_t); |
| int (*utime) (const char *, struct utimbuf *); |
| int (*open) (const char *, int); |
| int (*read) (const char *, char *, size_t, off_t); |
| int (*write) (const char *, const char *, size_t, off_t); |
| int (*statfs) (const char *, struct statfs *); |
| int (*flush) (const char *); |
| int (*release) (const char *, int); |
| int (*fsync) (const char *, int); |
| int (*setxattr) (const char *, const char *, const char *, size_t, int); |
| int (*getxattr) (const char *, const char *, char *, size_t); |
| int (*listxattr) (const char *, char *, size_t); |
| int (*removexattr) (const char *, const char *); |
| }; |
| |
| /** Extra context that may be needed by some filesystems */ |
| struct fuse_context { |
| uid_t uid; |
| gid_t gid; |
| }; |
| |
| #ifdef __cplusplus |
| extern "C" { |
| #endif |
| |
| /* |
| * Main function of FUSE. |
| * |
| * This is for the lazy. This is all that has to be called from the |
| * main() function. |
| * |
| * This function does the following: |
| * - parses command line options (-d -s and -h) |
| * - passes relevant mount options to the fuse_mount() |
| * - installs signal handlers for INT, HUP, TERM and PIPE |
| * - registers an exit handler to unmount the filesystem on program exit |
| * - creates a fuse handle |
| * - registers the operations |
| * - calls either the single-threaded or the multi-threaded event loop |
| * |
| * @param argc the argument counter passed to the main() function |
| * @param argv the argument vector passed to the main() function |
| * @param op the file system operation |
| */ |
| void fuse_main(int argc, char *argv[], const struct fuse_operations *op); |
| |
| /* |
| * Returns the fuse object created by fuse_main() |
| * |
| * This is useful when fuse_get_context() is used. |
| * |
| * @return the fuse object |
| */ |
| struct fuse *fuse_get(void); |
| |
| /** |
| * Invalidate cached data of a file. |
| * |
| * Useful if the 'kernel_cache' mount option is given, since in that |
| * case the cache is not invalidated on file open. |
| * |
| * @return 0 on success or -errno on failure |
| */ |
| int fuse_invalidate(struct fuse *f, const char *path); |
| |
| /* ----------------------------------------------------------- * |
| * More detailed API * |
| * ----------------------------------------------------------- */ |
| |
| /* |
| * Create a FUSE mountpoint |
| * |
| * Returns a control file descriptor suitable for passing to |
| * fuse_new() |
| * |
| * @param mountpoint the mount point path |
| * @param opts a comma separated list of mount options. Can be NULL. |
| * @return the control file descriptor on success, -1 on failure |
| */ |
| int fuse_mount(const char *mountpoint, const char *opts); |
| |
| /* |
| * Umount a FUSE mountpoint |
| * |
| * @param mountpoint the mount point path |
| */ |
| void fuse_unmount(const char *mountpoint); |
| |
| /** |
| * Create a new FUSE filesystem. |
| * |
| * @param fd the control file descriptor |
| * @param opts mount options to be used by the library |
| * @param op the operations |
| * @return the created FUSE handle |
| */ |
| struct fuse *fuse_new(int fd, const char *opts, |
| const struct fuse_operations *op); |
| |
| /** |
| * Destroy the FUSE handle. |
| * |
| * The filesystem is not unmounted. |
| * |
| * @param f the FUSE handle |
| */ |
| void fuse_destroy(struct fuse *f); |
| |
| /** |
| * FUSE event loop. |
| * |
| * Requests from the kernel are processed, and the apropriate |
| * operations are called. |
| * |
| * @param f the FUSE handle |
| */ |
| void fuse_loop(struct fuse *f); |
| |
| /** |
| * Exit from event loop |
| * |
| * @param f the FUSE handle |
| */ |
| void fuse_exit(struct fuse *f); |
| |
| /** |
| * FUSE event loop with multiple threads |
| * |
| * Requests from the kernel are processed, and the apropriate |
| * operations are called. Request are processed in parallel by |
| * distributing them between multiple threads. |
| * |
| * Calling this function requires the pthreads library to be linked to |
| * the application. |
| * |
| * @param f the FUSE handle |
| */ |
| void fuse_loop_mt(struct fuse *f); |
| |
| /** |
| * Get the current context |
| * |
| * The context is only valid for the duration of a filesystem |
| * operation, and thus must not be stored and used later. |
| * |
| * @param f the FUSE handle |
| * @return the context |
| */ |
| struct fuse_context *fuse_get_context(struct fuse *f); |
| |
| /** |
| * Check whether a mount option should be passed to the kernel or the |
| * library |
| * |
| * @param opt the option to check |
| * @return 1 if it is a library option, 0 otherwise |
| */ |
| int fuse_is_lib_option(const char *opt); |
| |
| |
| /* ----------------------------------------------------------- * |
| * Advanced API for event handling, don't worry about this... * |
| * ----------------------------------------------------------- */ |
| |
| struct fuse_cmd; |
| typedef void (*fuse_processor_t)(struct fuse *, struct fuse_cmd *, void *); |
| struct fuse_cmd *__fuse_read_cmd(struct fuse *f); |
| void __fuse_process_cmd(struct fuse *f, struct fuse_cmd *cmd); |
| void __fuse_loop_mt(struct fuse *f, fuse_processor_t proc, void *data); |
| int __fuse_exited(struct fuse* f); |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* _FUSE_H_ */ |