1 #ifndef FIO_FIFO_H
2 #define FIO_FIFO_H
3 /*
4 * A simple FIFO implementation.
5 *
6 * Copyright (C) 2004 Stelian Pop <stelian@popies.net>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 *
22 */
23 #include "minmax.h"
24
25 struct fifo {
26 unsigned char *buffer; /* the buffer holding the data */
27 unsigned int size; /* the size of the allocated buffer */
28 unsigned int in; /* data is added at offset (in % size) */
29 unsigned int out; /* data is extracted from off. (out % size) */
30 };
31
32 struct fifo *fifo_alloc(unsigned int);
33 unsigned int fifo_put(struct fifo *, void *, unsigned int);
34 unsigned int fifo_get(struct fifo *, void *, unsigned int);
35 void fifo_free(struct fifo *);
36
fifo_len(struct fifo * fifo)37 static inline unsigned int fifo_len(struct fifo *fifo)
38 {
39 return fifo->in - fifo->out;
40 }
41
fifo_room(struct fifo * fifo)42 static inline unsigned int fifo_room(struct fifo *fifo)
43 {
44 return fifo->size - fifo->in + fifo->out;
45 }
46
47 #endif
48