Statistics
| Branch: | Revision:

ffmpeg / libavutil / fifo.h @ 80a07f6e

History | View | Annotate | Download (3.49 KB)

1 f5a90186 Diego Biurrun
/*
2
 * This file is part of FFmpeg.
3
 *
4
 * FFmpeg is free software; you can redistribute it and/or
5
 * modify it under the terms of the GNU Lesser General Public
6
 * License as published by the Free Software Foundation; either
7
 * version 2.1 of the License, or (at your option) any later version.
8
 *
9
 * FFmpeg is distributed in the hope that it will be useful,
10
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12
 * Lesser General Public License for more details.
13
 *
14
 * You should have received a copy of the GNU Lesser General Public
15
 * License along with FFmpeg; if not, write to the Free Software
16
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17
 */
18
19 1faf7dc8 Dujardin Bernard
/**
20 bad5537e Diego Biurrun
 * @file libavutil/fifo.h
21 89c9ff50 Diego Biurrun
 * a very simple circular buffer FIFO implementation
22 1faf7dc8 Dujardin Bernard
 */
23
24 98790382 Stefano Sabatini
#ifndef AVUTIL_FIFO_H
25
#define AVUTIL_FIFO_H
26 f5a478f6 Roman Shaposhnik
27 99545457 Måns Rullgård
#include <stdint.h>
28 af5f434f Aurelien Jacobs
#include "avutil.h"
29 7c430093 Måns Rullgård
#include "common.h"
30 99545457 Måns Rullgård
31 f5a478f6 Roman Shaposhnik
typedef struct AVFifoBuffer {
32
    uint8_t *buffer;
33
    uint8_t *rptr, *wptr, *end;
34 0a71e78c Michael Niedermayer
    uint32_t rndx, wndx;
35 f5a478f6 Roman Shaposhnik
} AVFifoBuffer;
36
37 1faf7dc8 Dujardin Bernard
/**
38 82ffe191 Diego Biurrun
 * Initializes an AVFifoBuffer.
39 1faf7dc8 Dujardin Bernard
 * @param size of FIFO
40 41dd680d Michael Niedermayer
 * @return AVFifoBuffer or NULL if mem allocation failure
41 1faf7dc8 Dujardin Bernard
 */
42 41dd680d Michael Niedermayer
AVFifoBuffer *av_fifo_alloc(unsigned int size);
43 1faf7dc8 Dujardin Bernard
44
/**
45 82ffe191 Diego Biurrun
 * Frees an AVFifoBuffer.
46
 * @param *f AVFifoBuffer to free
47 1faf7dc8 Dujardin Bernard
 */
48 f5a478f6 Roman Shaposhnik
void av_fifo_free(AVFifoBuffer *f);
49 1faf7dc8 Dujardin Bernard
50
/**
51 32b936d0 Reimar Döffinger
 * Resets the AVFifoBuffer to the state right after av_fifo_alloc, in particular it is emptied.
52
 * @param *f AVFifoBuffer to reset
53
 */
54
void av_fifo_reset(AVFifoBuffer *f);
55
56
/**
57 82ffe191 Diego Biurrun
 * Returns the amount of data in bytes in the AVFifoBuffer, that is the
58
 * amount of data you can read from it.
59
 * @param *f AVFifoBuffer to read from
60 1faf7dc8 Dujardin Bernard
 * @return size
61
 */
62 f5a478f6 Roman Shaposhnik
int av_fifo_size(AVFifoBuffer *f);
63 1faf7dc8 Dujardin Bernard
64
/**
65 7b09db35 Olivier Guilyardi
 * Returns the amount of space in bytes in the AVFifoBuffer, that is the
66
 * amount of data you can write into it.
67
 * @param *f AVFifoBuffer to write into
68
 * @return size
69
 */
70
int av_fifo_space(AVFifoBuffer *f);
71
72
/**
73 89c9ff50 Diego Biurrun
 * Feeds data from an AVFifoBuffer to a user-supplied callback.
74 82ffe191 Diego Biurrun
 * @param *f AVFifoBuffer to read from
75
 * @param buf_size number of bytes to read
76 1faf7dc8 Dujardin Bernard
 * @param *func generic read function
77
 * @param *dest data destination
78
 */
79 3898eed8 Reimar Döffinger
int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void (*func)(void*, void*, int));
80 1faf7dc8 Dujardin Bernard
81 49cec199 Björn Axelsson
/**
82 89c9ff50 Diego Biurrun
 * Feeds data from a user-supplied callback to an AVFifoBuffer.
83 49cec199 Björn Axelsson
 * @param *f AVFifoBuffer to write to
84 95c76e11 Benoit Fouet
 * @param *src data source
85 49cec199 Björn Axelsson
 * @param size number of bytes to write
86 89c9ff50 Diego Biurrun
 * @param *func generic write function; the first parameter is src,
87
 * the second is dest_buf, the third is dest_buf_size.
88 49cec199 Björn Axelsson
 * func must return the number of bytes written to dest_buf, or <= 0 to
89
 * indicate no more data available to write.
90 95c76e11 Benoit Fouet
 * If func is NULL, src is interpreted as a simple byte array for source data.
91 89c9ff50 Diego Biurrun
 * @return the number of bytes written to the FIFO
92 49cec199 Björn Axelsson
 */
93 95c76e11 Benoit Fouet
int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int (*func)(void*, void*, int));
94 1faf7dc8 Dujardin Bernard
95
/**
96 8257b835 Stefano Sabatini
 * Resizes an AVFifoBuffer.
97
 * @param *f AVFifoBuffer to resize
98
 * @param size new AVFifoBuffer size in bytes
99 89c9ff50 Diego Biurrun
 * @return <0 for failure, >=0 otherwise
100 8257b835 Stefano Sabatini
 */
101
int av_fifo_realloc2(AVFifoBuffer *f, unsigned int size);
102
103
/**
104 82ffe191 Diego Biurrun
 * Reads and discards the specified amount of data from an AVFifoBuffer.
105
 * @param *f AVFifoBuffer to read from
106
 * @param size amount of data to read in bytes
107 1faf7dc8 Dujardin Bernard
 */
108 f5a478f6 Roman Shaposhnik
void av_fifo_drain(AVFifoBuffer *f, int size);
109
110
static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
111
{
112
    uint8_t *ptr = f->rptr + offs;
113
    if (ptr >= f->end)
114
        ptr -= f->end - f->buffer;
115
    return *ptr;
116
}
117 98790382 Stefano Sabatini
#endif /* AVUTIL_FIFO_H */