Files
UltraGrid/src/utils/ring_buffer.h
2019-02-21 16:57:07 +01:00

96 lines
3.4 KiB
C

/*
* FILE: utils/ring_buffer.h
* AUTHORS: Martin Benes <martinbenesh@gmail.com>
* Lukas Hejtmanek <xhejtman@ics.muni.cz>
* Petr Holub <hopet@ics.muni.cz>
* Milos Liska <xliska@fi.muni.cz>
* Jiri Matela <matela@ics.muni.cz>
* Dalibor Matura <255899@mail.muni.cz>
* Ian Wesley-Smith <iwsmith@cct.lsu.edu>
*
* Copyright (c) 2005-2010 CESNET z.s.p.o.
*
* Redistribution and use in source and binary forms, with or without
* modification, is permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
*
* This product includes software developed by CESNET z.s.p.o.
*
* 4. Neither the name of the CESNET nor the names of its contributors may be
* used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
* AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/*
* Provides abstraction for ring buffers.
* Note that it doesn't offer advanced synchronization primitives and
* therefore is mainly intended for one producer and one consumer.
*/
#ifndef __RING_BUFFER_H
#define __RING_BUFFER_H
#include "audio_buffer.h" // audio_buffer_api
#ifdef __cplusplus
extern "C" {
#endif
/**
* @warining ring_buffer is generally not thread safe. The exception is when
* one thread reads and the other writes to the ring buffer (producer-consumer).
*/
struct ring_buffer;
typedef struct ring_buffer ring_buffer_t;
struct ring_buffer *ring_buffer_init(int size);
void ring_buffer_destroy(struct ring_buffer * ring);
/*
* @param ring ring buffer structure
* @param out allocated buffer to read to
* @param max_len maximal amount of data
* @return actual data length read (ranges between 0 and max_len)
*/
int ring_buffer_read(struct ring_buffer * ring, char *out, int max_len);
void ring_buffer_write(struct ring_buffer * ring, const char *in, int len);
int ring_get_size(struct ring_buffer * ring);
/**
* Flushes all data from ring buffer
*/
void ring_buffer_flush(struct ring_buffer *ring);
/**
* Returns actual buffer usage
*/
int ring_get_current_size(struct ring_buffer * ring);
extern struct audio_buffer_api ring_buffer_fns;
#ifdef __cplusplus
}
#endif
#endif /* __RING_BUFFER_H */