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841 lines
26 KiB
841 lines
26 KiB
/* FUSE: Filesystem in Userspace
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Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
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This program can be distributed under the terms of the GNU LGPLv2.
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See the file COPYING.LIB.
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*/
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/** @file */
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#if !defined(FUSE_H_) && !defined(FUSE_LOWLEVEL_H_)
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#error "Never include <fuse_common.h> directly; use <fuse.h> or <fuse_lowlevel.h> instead."
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#endif
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#ifndef FUSE_COMMON_H_
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#define FUSE_COMMON_H_
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#include "fuse_opt.h"
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#include "fuse_log.h"
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#include <stdint.h>
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#include <sys/types.h>
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/** Major version of FUSE library interface */
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#define FUSE_MAJOR_VERSION 3
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/** Minor version of FUSE library interface */
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#define FUSE_MINOR_VERSION 2
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#define FUSE_MAKE_VERSION(maj, min) ((maj) * 10 + (min))
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#define FUSE_VERSION FUSE_MAKE_VERSION(FUSE_MAJOR_VERSION, FUSE_MINOR_VERSION)
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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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* Information about an open file.
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*
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* File Handles are created by the open, opendir, and create methods and closed
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* by the release and releasedir methods. Multiple file handles may be
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* concurrently open for the same file. Generally, a client will create one
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* file handle per file descriptor, though in some cases multiple file
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* descriptors can share a single file handle.
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*/
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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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/** In case of a write operation indicates if this was caused
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by a delayed write from the page cache. If so, then the
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context's pid, uid, and gid fields will not be valid, and
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the *fh* value may not match the *fh* value that would
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have been sent with the corresponding individual write
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requests if write caching had been disabled. */
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unsigned int writepage : 1;
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/** Can be filled in by open, to use direct I/O on this file. */
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unsigned int direct_io : 1;
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/** Can be filled in by open. It signals the kernel that any
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currently cached file data (ie., data that the filesystem
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provided the last time the file was open) need not be
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invalidated. Has no effect when set in other contexts (in
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particular it does nothing when set by opendir()). */
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unsigned int keep_cache : 1;
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/** Indicates a flush operation. Set in flush operation, also
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maybe set in highlevel lock operation and lowlevel release
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operation. */
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unsigned int flush : 1;
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/** Can be filled in by open, to indicate that the file is not
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seekable. */
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unsigned int nonseekable : 1;
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/* Indicates that flock locks for this file should be
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released. If set, lock_owner shall contain a valid value.
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May only be set in ->release(). */
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unsigned int flock_release : 1;
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/** Can be filled in by opendir. It signals the kernel to
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enable caching of entries returned by readdir(). Has no
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effect when set in other contexts (in particular it does
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nothing when set by open()). */
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unsigned int cache_readdir : 1;
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/** Padding. Reserved for future use*/
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unsigned int padding : 25;
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unsigned int padding2 : 32;
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/** File handle id. May be filled in by filesystem in create,
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* open, and opendir(). Available in most other file operations on the
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* same file handle. */
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uint64_t fh;
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/** Passthrough file handle id. May be filled in by filesystem in
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* create and open. It is used to create a passthrough connection
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* between FUSE file and lower file system file. */
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uint32_t passthrough_fh;
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/** Lock owner id. Available in locking operations and flush */
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uint64_t lock_owner;
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/** Requested poll events. Available in ->poll. Only set on kernels
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which support it. If unsupported, this field is set to zero. */
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uint32_t poll_events;
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};
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/**
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* Configuration parameters passed to fuse_session_loop_mt() and
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* fuse_loop_mt().
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*/
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struct fuse_loop_config {
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/**
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* whether to use separate device fds for each thread
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* (may increase performance)
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*/
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int clone_fd;
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/**
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* The maximum number of available worker threads before they
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* start to get deleted when they become idle. If not
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* specified, the default is 10.
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*
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* Adjusting this has performance implications; a very small number
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* of threads in the pool will cause a lot of thread creation and
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* deletion overhead and performance may suffer. When set to 0, a new
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* thread will be created to service every operation.
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*/
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unsigned int max_idle_threads;
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};
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/**************************************************************************
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* Capability bits for 'fuse_conn_info.capable' and 'fuse_conn_info.want' *
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**************************************************************************/
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/**
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* Indicates that the filesystem supports asynchronous read requests.
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*
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* If this capability is not requested/available, the kernel will
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* ensure that there is at most one pending read request per
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* file-handle at any time, and will attempt to order read requests by
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* increasing offset.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_ASYNC_READ (1 << 0)
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/**
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* Indicates that the filesystem supports "remote" locking.
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*
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* This feature is enabled by default when supported by the kernel,
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* and if getlk() and setlk() handlers are implemented.
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*/
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#define FUSE_CAP_POSIX_LOCKS (1 << 1)
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/**
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* Indicates that the filesystem supports the O_TRUNC open flag. If
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* disabled, and an application specifies O_TRUNC, fuse first calls
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* truncate() and then open() with O_TRUNC filtered out.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_ATOMIC_O_TRUNC (1 << 3)
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/**
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* Indicates that the filesystem supports lookups of "." and "..".
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_EXPORT_SUPPORT (1 << 4)
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/**
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* Indicates that the kernel should not apply the umask to the
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* file mode on create operations.
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_DONT_MASK (1 << 6)
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/**
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* Indicates that libfuse should try to use splice() when writing to
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* the fuse device. This may improve performance.
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_SPLICE_WRITE (1 << 7)
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/**
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* Indicates that libfuse should try to move pages instead of copying when
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* writing to / reading from the fuse device. This may improve performance.
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_SPLICE_MOVE (1 << 8)
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/**
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* Indicates that libfuse should try to use splice() when reading from
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* the fuse device. This may improve performance.
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*
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* This feature is enabled by default when supported by the kernel and
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* if the filesystem implements a write_buf() handler.
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*/
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#define FUSE_CAP_SPLICE_READ (1 << 9)
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/**
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* If set, the calls to flock(2) will be emulated using POSIX locks and must
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* then be handled by the filesystem's setlock() handler.
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*
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* If not set, flock(2) calls will be handled by the FUSE kernel module
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* internally (so any access that does not go through the kernel cannot be taken
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* into account).
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*
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* This feature is enabled by default when supported by the kernel and
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* if the filesystem implements a flock() handler.
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*/
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#define FUSE_CAP_FLOCK_LOCKS (1 << 10)
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/**
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* Indicates that the filesystem supports ioctl's on directories.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_IOCTL_DIR (1 << 11)
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/**
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* Traditionally, while a file is open the FUSE kernel module only
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* asks the filesystem for an update of the file's attributes when a
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* client attempts to read beyond EOF. This is unsuitable for
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* e.g. network filesystems, where the file contents may change
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* without the kernel knowing about it.
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*
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* If this flag is set, FUSE will check the validity of the attributes
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* on every read. If the attributes are no longer valid (i.e., if the
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* *attr_timeout* passed to fuse_reply_attr() or set in `struct
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* fuse_entry_param` has passed), it will first issue a `getattr`
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* request. If the new mtime differs from the previous value, any
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* cached file *contents* will be invalidated as well.
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*
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* This flag should always be set when available. If all file changes
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* go through the kernel, *attr_timeout* should be set to a very large
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* number to avoid unnecessary getattr() calls.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_AUTO_INVAL_DATA (1 << 12)
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/**
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* Indicates that the filesystem supports readdirplus.
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*
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* This feature is enabled by default when supported by the kernel and if the
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* filesystem implements a readdirplus() handler.
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*/
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#define FUSE_CAP_READDIRPLUS (1 << 13)
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/**
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* Indicates that the filesystem supports adaptive readdirplus.
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*
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* If FUSE_CAP_READDIRPLUS is not set, this flag has no effect.
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*
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* If FUSE_CAP_READDIRPLUS is set and this flag is not set, the kernel
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* will always issue readdirplus() requests to retrieve directory
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* contents.
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*
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* If FUSE_CAP_READDIRPLUS is set and this flag is set, the kernel
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* will issue both readdir() and readdirplus() requests, depending on
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* how much information is expected to be required.
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*
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* As of Linux 4.20, the algorithm is as follows: when userspace
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* starts to read directory entries, issue a READDIRPLUS request to
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* the filesystem. If any entry attributes have been looked up by the
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* time userspace requests the next batch of entries continue with
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* READDIRPLUS, otherwise switch to plain READDIR. This will reasult
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* in eg plain "ls" triggering READDIRPLUS first then READDIR after
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* that because it doesn't do lookups. "ls -l" should result in all
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* READDIRPLUS, except if dentries are already cached.
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*
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* This feature is enabled by default when supported by the kernel and
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* if the filesystem implements both a readdirplus() and a readdir()
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* handler.
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*/
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#define FUSE_CAP_READDIRPLUS_AUTO (1 << 14)
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/**
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* Indicates that the filesystem supports asynchronous direct I/O submission.
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*
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* If this capability is not requested/available, the kernel will ensure that
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* there is at most one pending read and one pending write request per direct
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* I/O file-handle at any time.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_ASYNC_DIO (1 << 15)
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/**
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* Indicates that writeback caching should be enabled. This means that
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* individual write request may be buffered and merged in the kernel
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* before they are send to the filesystem.
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_WRITEBACK_CACHE (1 << 16)
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/**
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* Indicates support for zero-message opens. If this flag is set in
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* the `capable` field of the `fuse_conn_info` structure, then the
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* filesystem may return `ENOSYS` from the open() handler to indicate
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* success. Further attempts to open files will be handled in the
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* kernel. (If this flag is not set, returning ENOSYS will be treated
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* as an error and signaled to the caller).
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*
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* Setting (or unsetting) this flag in the `want` field has *no
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* effect*.
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*/
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#define FUSE_CAP_NO_OPEN_SUPPORT (1 << 17)
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/**
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* Indicates support for parallel directory operations. If this flag
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* is unset, the FUSE kernel module will ensure that lookup() and
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* readdir() requests are never issued concurrently for the same
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* directory.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_PARALLEL_DIROPS (1 << 18)
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/**
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* Indicates support for POSIX ACLs.
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*
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* If this feature is enabled, the kernel will cache and have
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* responsibility for enforcing ACLs. ACL will be stored as xattrs and
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* passed to userspace, which is responsible for updating the ACLs in
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* the filesystem, keeping the file mode in sync with the ACL, and
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* ensuring inheritance of default ACLs when new filesystem nodes are
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* created. Note that this requires that the file system is able to
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* parse and interpret the xattr representation of ACLs.
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*
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* Enabling this feature implicitly turns on the
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* ``default_permissions`` mount option (even if it was not passed to
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* mount(2)).
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_POSIX_ACL (1 << 19)
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/**
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* Indicates that the filesystem is responsible for unsetting
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* setuid and setgid bits when a file is written, truncated, or
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* its owner is changed.
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*
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* This feature is enabled by default when supported by the kernel.
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*/
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#define FUSE_CAP_HANDLE_KILLPRIV (1 << 20)
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/**
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* Indicates support for zero-message opendirs. If this flag is set in
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* the `capable` field of the `fuse_conn_info` structure, then the filesystem
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* may return `ENOSYS` from the opendir() handler to indicate success. Further
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* opendir and releasedir messages will be handled in the kernel. (If this
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* flag is not set, returning ENOSYS will be treated as an error and signalled
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* to the caller.)
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*
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* Setting (or unsetting) this flag in the `want` field has *no effect*.
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*/
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#define FUSE_CAP_NO_OPENDIR_SUPPORT (1 << 24)
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/**
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* Indicates support for passthrough mode access for read/write operations.
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*
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* If this flag is set in the `capable` field of the `fuse_conn_info`
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* structure, then the FUSE kernel module supports redirecting read/write
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* operations to the lower file system instead of letting them to be handled
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* by the FUSE daemon.
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*
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* This feature is disabled by default.
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*/
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#define FUSE_CAP_PASSTHROUGH (1 << 31)
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/**
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* Ioctl flags
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*
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* FUSE_IOCTL_COMPAT: 32bit compat ioctl on 64bit machine
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* FUSE_IOCTL_UNRESTRICTED: not restricted to well-formed ioctls, retry allowed
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* FUSE_IOCTL_RETRY: retry with new iovecs
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* FUSE_IOCTL_DIR: is a directory
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*
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* FUSE_IOCTL_MAX_IOV: maximum of in_iovecs + out_iovecs
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*/
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#define FUSE_IOCTL_COMPAT (1 << 0)
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#define FUSE_IOCTL_UNRESTRICTED (1 << 1)
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#define FUSE_IOCTL_RETRY (1 << 2)
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#define FUSE_IOCTL_DIR (1 << 4)
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#define FUSE_IOCTL_MAX_IOV 256
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/**
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* Connection information, passed to the ->init() method
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*
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* Some of the elements are read-write, these can be changed to
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* indicate the value requested by the filesystem. The requested
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* value must usually be smaller than the indicated value.
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*/
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struct fuse_conn_info {
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/**
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* Major version of the protocol (read-only)
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*/
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unsigned proto_major;
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/**
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* Minor version of the protocol (read-only)
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*/
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unsigned proto_minor;
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/**
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* Maximum size of the write buffer
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*/
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unsigned max_write;
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/**
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* Maximum size of read requests. A value of zero indicates no
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* limit. However, even if the filesystem does not specify a
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* limit, the maximum size of read requests will still be
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* limited by the kernel.
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*
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* NOTE: For the time being, the maximum size of read requests
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* must be set both here *and* passed to fuse_session_new()
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* using the ``-o max_read=<n>`` mount option. At some point
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* in the future, specifying the mount option will no longer
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* be necessary.
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*/
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unsigned max_read;
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/**
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* Maximum readahead
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*/
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unsigned max_readahead;
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/**
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* Capability flags that the kernel supports (read-only)
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*/
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unsigned capable;
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/**
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* Capability flags that the filesystem wants to enable.
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*
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* libfuse attempts to initialize this field with
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* reasonable default values before calling the init() handler.
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*/
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unsigned want;
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/**
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* Maximum number of pending "background" requests. A
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* background request is any type of request for which the
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* total number is not limited by other means. As of kernel
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* 4.8, only two types of requests fall into this category:
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*
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* 1. Read-ahead requests
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* 2. Asynchronous direct I/O requests
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*
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* Read-ahead requests are generated (if max_readahead is
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* non-zero) by the kernel to preemptively fill its caches
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* when it anticipates that userspace will soon read more
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* data.
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*
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* Asynchronous direct I/O requests are generated if
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* FUSE_CAP_ASYNC_DIO is enabled and userspace submits a large
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* direct I/O request. In this case the kernel will internally
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* split it up into multiple smaller requests and submit them
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* to the filesystem concurrently.
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*
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* Note that the following requests are *not* background
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* requests: writeback requests (limited by the kernel's
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* flusher algorithm), regular (i.e., synchronous and
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* buffered) userspace read/write requests (limited to one per
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* thread), asynchronous read requests (Linux's io_submit(2)
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* call actually blocks, so these are also limited to one per
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* thread).
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*/
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unsigned max_background;
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/**
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* Kernel congestion threshold parameter. If the number of pending
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* background requests exceeds this number, the FUSE kernel module will
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* mark the filesystem as "congested". This instructs the kernel to
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* expect that queued requests will take some time to complete, and to
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* adjust its algorithms accordingly (e.g. by putting a waiting thread
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* to sleep instead of using a busy-loop).
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*/
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unsigned congestion_threshold;
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/**
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* When FUSE_CAP_WRITEBACK_CACHE is enabled, the kernel is responsible
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* for updating mtime and ctime when write requests are received. The
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* updated values are passed to the filesystem with setattr() requests.
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* However, if the filesystem does not support the full resolution of
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* the kernel timestamps (nanoseconds), the mtime and ctime values used
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* by kernel and filesystem will differ (and result in an apparent
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* change of times after a cache flush).
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*
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* To prevent this problem, this variable can be used to inform the
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* kernel about the timestamp granularity supported by the file-system.
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* The value should be power of 10. The default is 1, i.e. full
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* nano-second resolution. Filesystems supporting only second resolution
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* should set this to 1000000000.
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*/
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unsigned time_gran;
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|
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/**
|
|
* For future use.
|
|
*/
|
|
unsigned reserved[22];
|
|
};
|
|
|
|
struct fuse_session;
|
|
struct fuse_pollhandle;
|
|
struct fuse_conn_info_opts;
|
|
|
|
/**
|
|
* This function parses several command-line options that can be used
|
|
* to override elements of struct fuse_conn_info. The pointer returned
|
|
* by this function should be passed to the
|
|
* fuse_apply_conn_info_opts() method by the file system's init()
|
|
* handler.
|
|
*
|
|
* Before using this function, think twice if you really want these
|
|
* parameters to be adjustable from the command line. In most cases,
|
|
* they should be determined by the file system internally.
|
|
*
|
|
* The following options are recognized:
|
|
*
|
|
* -o max_write=N sets conn->max_write
|
|
* -o max_readahead=N sets conn->max_readahead
|
|
* -o max_background=N sets conn->max_background
|
|
* -o congestion_threshold=N sets conn->congestion_threshold
|
|
* -o async_read sets FUSE_CAP_ASYNC_READ in conn->want
|
|
* -o sync_read unsets FUSE_CAP_ASYNC_READ in conn->want
|
|
* -o atomic_o_trunc sets FUSE_CAP_ATOMIC_O_TRUNC in conn->want
|
|
* -o no_remote_lock Equivalent to -o no_remote_flock,no_remote_posix_lock
|
|
* -o no_remote_flock Unsets FUSE_CAP_FLOCK_LOCKS in conn->want
|
|
* -o no_remote_posix_lock Unsets FUSE_CAP_POSIX_LOCKS in conn->want
|
|
* -o [no_]splice_write (un-)sets FUSE_CAP_SPLICE_WRITE in conn->want
|
|
* -o [no_]splice_move (un-)sets FUSE_CAP_SPLICE_MOVE in conn->want
|
|
* -o [no_]splice_read (un-)sets FUSE_CAP_SPLICE_READ in conn->want
|
|
* -o [no_]auto_inval_data (un-)sets FUSE_CAP_AUTO_INVAL_DATA in conn->want
|
|
* -o readdirplus=no unsets FUSE_CAP_READDIRPLUS in conn->want
|
|
* -o readdirplus=yes sets FUSE_CAP_READDIRPLUS and unsets
|
|
* FUSE_CAP_READDIRPLUS_AUTO in conn->want
|
|
* -o readdirplus=auto sets FUSE_CAP_READDIRPLUS and
|
|
* FUSE_CAP_READDIRPLUS_AUTO in conn->want
|
|
* -o [no_]async_dio (un-)sets FUSE_CAP_ASYNC_DIO in conn->want
|
|
* -o [no_]writeback_cache (un-)sets FUSE_CAP_WRITEBACK_CACHE in conn->want
|
|
* -o time_gran=N sets conn->time_gran
|
|
*
|
|
* Known options will be removed from *args*, unknown options will be
|
|
* passed through unchanged.
|
|
*
|
|
* @param args argument vector (input+output)
|
|
* @return parsed options
|
|
**/
|
|
struct fuse_conn_info_opts* fuse_parse_conn_info_opts(struct fuse_args *args);
|
|
|
|
/**
|
|
* This function applies the (parsed) parameters in *opts* to the
|
|
* *conn* pointer. It may modify the following fields: wants,
|
|
* max_write, max_readahead, congestion_threshold, max_background,
|
|
* time_gran. A field is only set (or unset) if the corresponding
|
|
* option has been explicitly set.
|
|
*/
|
|
void fuse_apply_conn_info_opts(struct fuse_conn_info_opts *opts,
|
|
struct fuse_conn_info *conn);
|
|
|
|
/**
|
|
* 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);
|
|
|
|
/**
|
|
* Get the full package version string of the library
|
|
*
|
|
* @return the package version
|
|
*/
|
|
const char *fuse_pkgversion(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.
|
|
*
|
|
* Once either of the POSIX signals arrives, the signal handler calls
|
|
* fuse_session_exit().
|
|
*
|
|
* @param se the session to exit
|
|
* @return 0 on success, -1 on failure
|
|
*
|
|
* See also:
|
|
* fuse_remove_signal_handlers()
|
|
*/
|
|
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()
|
|
*
|
|
* See also:
|
|
* fuse_set_signal_handlers()
|
|
*/
|
|
void fuse_remove_signal_handlers(struct fuse_session *se);
|
|
|
|
/* ----------------------------------------------------------- *
|
|
* Compatibility stuff *
|
|
* ----------------------------------------------------------- */
|
|
|
|
#if !defined(FUSE_USE_VERSION) || FUSE_USE_VERSION < 30
|
|
# error only API version 30 or greater is supported
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
|
|
/*
|
|
* This interface uses 64 bit off_t.
|
|
*
|
|
* On 32bit systems please add -D_FILE_OFFSET_BITS=64 to your compile flags!
|
|
*/
|
|
|
|
#if defined(__GNUC__) && (__GNUC__ > 4 || __GNUC__ == 4 && __GNUC_MINOR__ >= 6) && !defined __cplusplus
|
|
_Static_assert(sizeof(off_t) == 8, "fuse: off_t must be 64bit");
|
|
#else
|
|
struct _fuse_off_t_must_be_64bit_dummy_struct \
|
|
{ unsigned _fuse_off_t_must_be_64bit:((sizeof(off_t) == 8) ? 1 : -1); };
|
|
#endif
|
|
|
|
#endif /* FUSE_COMMON_H_ */
|