Doxygen documentation for all functions, patch by Dujardin Bernard,
[libav.git] / libavutil / fifo.h
1 /*
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 /**
20 * @file fifo.h
21 * A very simple circular buffer FIFO implementation.
22 */
23
24 #ifndef FIFO_H
25 #define FIFO_H
26
27 typedef struct AVFifoBuffer {
28 uint8_t *buffer;
29 uint8_t *rptr, *wptr, *end;
30 } AVFifoBuffer;
31
32 /**
33 * Initializes a FIFO *.
34 * @param *f FIFO buffer
35 * @param size of FIFO
36 * @return <0 for failure >=0 otherwise
37 */
38 int av_fifo_init(AVFifoBuffer *f, int size);
39
40 /**
41 * Frees a FIFO *.
42 * @param *f FIFO buffer
43 */
44 void av_fifo_free(AVFifoBuffer *f);
45
46 /**
47 * Returns the size of a FIFO *.
48 * @param *f FIFO buffer
49 * @return size
50 */
51 int av_fifo_size(AVFifoBuffer *f);
52
53 /**
54 * Reads the data from the FIFO *.
55 * @param *f FIFO buffer
56 * @param *buf data destination
57 * @param buf_size data size
58 * @return -1 if not enough data
59 */
60 int av_fifo_read(AVFifoBuffer *f, uint8_t *buf, int buf_size);
61
62 /**
63 * Reads the data from the FIFO *.
64 * @param *f FIFO buffer
65 * @param buf_size data size
66 * @param *func generic read function
67 * @param *dest data destination
68 * @return -1 if not enough data
69 */
70 int av_fifo_generic_read(AVFifoBuffer *f, int buf_size, void (*func)(void*, void*, int), void* dest);
71
72 /**
73 * Writes the data in the FIFO *.
74 * @param *f FIFO buffer
75 * @param *buf data source
76 * @param size data size
77 */
78 void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size);
79
80 /**
81 * Resizes the FIFO *.
82 * @param *f FIFO buffer
83 * @param size data size
84 */
85 void av_fifo_realloc(AVFifoBuffer *f, unsigned int size);
86
87 /**
88 * Discards the data from the FIFO *.
89 * @param *f FIFO buffer
90 * @param size data size
91 */
92 void av_fifo_drain(AVFifoBuffer *f, int size);
93
94 /**
95 * Returns a pointer with circular offset from FIFO's read pointer.
96 * @param *f FIFO buffer
97 * @param offs offset
98 * @return ptr=rptr+offs if rptr+offs<end else rptr+offs -(end-begin)
99 */
100 static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
101 {
102 uint8_t *ptr = f->rptr + offs;
103 if (ptr >= f->end)
104 ptr -= f->end - f->buffer;
105 return *ptr;
106 }
107 #endif /* FIFO_H */