mirror of
https://github.com/transmission/transmission
synced 2024-12-26 17:47:37 +00:00
97 lines
2 KiB
C
97 lines
2 KiB
C
/*
|
|
* Copyright (c) 2004-2005 Sergey Lyubka <valenok@gmail.com>
|
|
* All rights reserved
|
|
*
|
|
* "THE BEER-WARE LICENSE" (Revision 42):
|
|
* Sergey Lyubka wrote this file. As long as you retain this notice you
|
|
* can do whatever you want with this stuff. If we meet some day, and you think
|
|
* this stuff is worth it, you can buy me a beer in return.
|
|
*/
|
|
|
|
#ifndef IO_HEADER_INCLUDED
|
|
#define IO_HEADER_INCLUDED
|
|
|
|
#include <assert.h>
|
|
#include <stddef.h>
|
|
|
|
/*
|
|
* I/O buffer descriptor
|
|
*/
|
|
struct io {
|
|
char *buf; /* IO Buffer */
|
|
size_t size; /* IO buffer size */
|
|
size_t head; /* Bytes read */
|
|
size_t tail; /* Bytes written */
|
|
size_t total; /* Total bytes read */
|
|
};
|
|
|
|
static __inline void
|
|
io_clear(struct io *io)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
io->total = io->tail = io->head = 0;
|
|
}
|
|
|
|
static __inline char *
|
|
io_space(struct io *io)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
assert(io->head <= io->size);
|
|
return (io->buf + io->head);
|
|
}
|
|
|
|
static __inline char *
|
|
io_data(struct io *io)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
assert(io->tail <= io->size);
|
|
return (io->buf + io->tail);
|
|
}
|
|
|
|
static __inline size_t
|
|
io_space_len(const struct io *io)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
assert(io->head <= io->size);
|
|
return (io->size - io->head);
|
|
}
|
|
|
|
static __inline size_t
|
|
io_data_len(const struct io *io)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
assert(io->head <= io->size);
|
|
assert(io->tail <= io->head);
|
|
return (io->head - io->tail);
|
|
}
|
|
|
|
static __inline void
|
|
io_inc_tail(struct io *io, size_t n)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
assert(io->tail <= io->head);
|
|
assert(io->head <= io->size);
|
|
io->tail += n;
|
|
assert(io->tail <= io->head);
|
|
if (io->tail == io->head)
|
|
io->head = io->tail = 0;
|
|
}
|
|
|
|
static __inline void
|
|
io_inc_head(struct io *io, size_t n)
|
|
{
|
|
assert(io->buf != NULL);
|
|
assert(io->size > 0);
|
|
assert(io->tail <= io->head);
|
|
io->head += n;
|
|
io->total += n;
|
|
assert(io->head <= io->size);
|
|
}
|
|
|
|
#endif /* IO_HEADER_INCLUDED */
|