Use full internal pathname in doxygen @file directives.
[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 libavutil/fifo.h
21 * a very simple circular buffer FIFO implementation
22 */
23
24 #ifndef AVUTIL_FIFO_H
25 #define AVUTIL_FIFO_H
26
27 #include <stdint.h>
28 #include "avutil.h"
29 #include "common.h"
30
31 typedef struct AVFifoBuffer {
32 uint8_t *buffer;
33 uint8_t *rptr, *wptr, *end;
34 } AVFifoBuffer;
35
36 /**
37 * Initializes an AVFifoBuffer.
38 * @param *f AVFifoBuffer to initialize
39 * @param size of FIFO
40 * @return <0 for failure >=0 otherwise
41 */
42 int av_fifo_init(AVFifoBuffer *f, unsigned int size);
43
44 /**
45 * Frees an AVFifoBuffer.
46 * @param *f AVFifoBuffer to free
47 */
48 void av_fifo_free(AVFifoBuffer *f);
49
50 /**
51 * Returns the amount of data in bytes in the AVFifoBuffer, that is the
52 * amount of data you can read from it.
53 * @param *f AVFifoBuffer to read from
54 * @return size
55 */
56 int av_fifo_size(AVFifoBuffer *f);
57
58 /**
59 * Reads data from an AVFifoBuffer.
60 * @param *f AVFifoBuffer to read from
61 * @param *buf data destination
62 * @param buf_size number of bytes to read
63 */
64 int av_fifo_read(AVFifoBuffer *f, uint8_t *buf, int buf_size);
65
66 /**
67 * Feeds data from an AVFifoBuffer to a user-supplied callback.
68 * @param *f AVFifoBuffer to read from
69 * @param buf_size number of bytes to read
70 * @param *func generic read function
71 * @param *dest data destination
72 */
73 int av_fifo_generic_read(AVFifoBuffer *f, int buf_size, void (*func)(void*, void*, int), void* dest);
74
75 #if LIBAVUTIL_VERSION_MAJOR < 50
76 /**
77 * Writes data into an AVFifoBuffer.
78 * @param *f AVFifoBuffer to write to
79 * @param *buf data source
80 * @param size data size
81 */
82 attribute_deprecated void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size);
83 #endif
84
85 /**
86 * Feeds data from a user-supplied callback to an AVFifoBuffer.
87 * @param *f AVFifoBuffer to write to
88 * @param *src data source
89 * @param size number of bytes to write
90 * @param *func generic write function; the first parameter is src,
91 * the second is dest_buf, the third is dest_buf_size.
92 * func must return the number of bytes written to dest_buf, or <= 0 to
93 * indicate no more data available to write.
94 * If func is NULL, src is interpreted as a simple byte array for source data.
95 * @return the number of bytes written to the FIFO
96 */
97 int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int (*func)(void*, void*, int));
98
99 #if LIBAVUTIL_VERSION_MAJOR < 50
100 /**
101 * Resizes an AVFifoBuffer.
102 * @param *f AVFifoBuffer to resize
103 * @param size new AVFifoBuffer size in bytes
104 * @see av_fifo_realloc2()
105 */
106 attribute_deprecated void av_fifo_realloc(AVFifoBuffer *f, unsigned int size);
107 #endif
108
109 /**
110 * Resizes an AVFifoBuffer.
111 * @param *f AVFifoBuffer to resize
112 * @param size new AVFifoBuffer size in bytes
113 * @return <0 for failure, >=0 otherwise
114 */
115 int av_fifo_realloc2(AVFifoBuffer *f, unsigned int size);
116
117 /**
118 * Reads and discards the specified amount of data from an AVFifoBuffer.
119 * @param *f AVFifoBuffer to read from
120 * @param size amount of data to read in bytes
121 */
122 void av_fifo_drain(AVFifoBuffer *f, int size);
123
124 static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
125 {
126 uint8_t *ptr = f->rptr + offs;
127 if (ptr >= f->end)
128 ptr -= f->end - f->buffer;
129 return *ptr;
130 }
131 #endif /* AVUTIL_FIFO_H */