/* $NetBSD: buf.h,v 1.1 2022/01/22 07:54:57 pho Exp $ */
/*
* Copyright (c) 2021 The NetBSD Foundation, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#if !defined(_FUSE_BUF_H_)
#define _FUSE_BUF_H_
#include <sys/types.h>
/* Data buffer API, appeared on FUSE 2.9. */
#if !defined(FUSE_H_)
# error Do not include this header directly. Include <fuse.h> instead.
#endif
#ifdef __cplusplus
extern "C" {
#endif
enum fuse_buf_flags {
/* The buffer is actually an fd: .mem is invalid but .fd and
* .pos have valid values. */
FUSE_BUF_IS_FD = (1 << 1),
/* The fd is seekable. */
FUSE_BUF_FD_SEEK = (1 << 2),
/* Keep reading from/writing to the fd until reaching EOF. */
FUSE_BUF_FD_RETRY = (1 << 3),
};
enum fuse_buf_copy_flags {
/* These flags are always ignored because splice(2) is a
* Linux-specific syscall and there are no alternatives on
* NetBSD atm. */
FUSE_BUF_NO_SPLICE = (1 << 1),
FUSE_BUF_FORCE_SPLICE = (1 << 2),
FUSE_BUF_SPLICE_MOVE = (1 << 3),
FUSE_BUF_SPLICE_NONBLOCK = (1 << 4),
};
struct fuse_buf {
size_t size;
enum fuse_buf_flags flags;
void *mem;
int fd;
off_t pos;
};
struct fuse_bufvec {
/* The number of buffers in the vector. */
size_t count;
/* The index of the current buffer in the vector. */
size_t idx;
/* The current offset in the current buffer. */
size_t off;
/* The vector of buffers. */
struct fuse_buf buf[1];
};
#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 the total size of data in a buffer vector. */
size_t fuse_buf_size(const struct fuse_bufvec *bufv);
/* Copy data from one buffer vector to another, and return the number
* of octets that have been copied. */
ssize_t fuse_buf_copy(struct fuse_bufvec *dstv, struct fuse_bufvec *srcv,
enum fuse_buf_copy_flags flags);
#ifdef __cplusplus
}
#endif
#endif