ringbuffer.h

Go to the documentation of this file.

/*
 * SPDX-FileCopyrightText: 2013 Freie Universität Berlin
 * SPDX-FileCopyrightText: 2013 INRIA
 * SPDX-License-Identifier: LGPL-2.1-only
 */
 
#pragma once

 
#include "compiler_hints.h"
 
#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
    char *buf;          
    unsigned int size;  
    unsigned int start; 
    unsigned int avail; 
} ringbuffer_t;

#define RINGBUFFER_INIT(BUF) { (BUF), sizeof(BUF), 0, 0 }

ACCESS(write_only, 2, 3)
static inline void ringbuffer_init(ringbuffer_t *__restrict rb, char *buffer,
                                   unsigned bufsize)
{
    rb->buf = buffer;
    rb->size = bufsize;
    rb->start = 0;
    rb->avail = 0;
}

int ringbuffer_add_one(ringbuffer_t *__restrict rb, char c);

ACCESS(read_only, 2, 3)
unsigned ringbuffer_add(ringbuffer_t *__restrict rb, const char *buf,
                        unsigned n);

int ringbuffer_get_one(ringbuffer_t *__restrict rb);

ACCESS(write_only, 2, 3)
unsigned ringbuffer_get(ringbuffer_t *__restrict rb, char *buf, unsigned n);

unsigned ringbuffer_remove(ringbuffer_t *__restrict rb, unsigned n);

static inline int ringbuffer_empty(const ringbuffer_t *__restrict rb)
{
    return rb->avail == 0;
}

static inline int ringbuffer_full(const ringbuffer_t *__restrict rb)
{
    return rb->avail == rb->size;
}

static inline unsigned int ringbuffer_get_free(
    const ringbuffer_t *__restrict rb)
{
    return rb->size - rb->avail;
}

int ringbuffer_peek_one(const ringbuffer_t *__restrict rb);

ACCESS(write_only, 2, 3)
unsigned ringbuffer_peek(const ringbuffer_t *__restrict rb, char *buf,
                         unsigned n);
 
#ifdef __cplusplus
}
#endif