ring_buffer.h

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 /*
  * 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
 
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);
void ring_buffer_flush(struct ring_buffer *ring);
int ring_get_current_size(struct ring_buffer * ring);
 
int ring_get_available_write_size(struct ring_buffer * ring);
 
 
int ring_get_read_regions(struct ring_buffer *ring, int max_len,
                void **ptr1, int *size1,
                void **ptr2, int *size2);
 
void ring_advance_read_idx(struct ring_buffer *ring, int amount);
 
int ring_get_write_regions(struct ring_buffer *ring, int requested_len,
                void **ptr1, int *size1,
                void **ptr2, int *size2);
 
bool ring_advance_write_idx(struct ring_buffer *ring, int amount);
 
void ring_fill(struct ring_buffer *ring, int c, int size);
 
extern struct audio_buffer_api ring_buffer_fns;
 
#ifdef __cplusplus
}
 
#include <memory>
 
struct ring_buf_deleter{ void operator()(ring_buffer_t* ring) { ring_buffer_destroy(ring); } };
using ring_buffer_uniq = std::unique_ptr<ring_buffer, ring_buf_deleter>;
 
#endif //__cplusplus
 
#endif /* __RING_BUFFER_H */