ring.h

/*
 * Copyright (c) 2015-2021 by Willem Dijkstra <wpd@xs4all.nl>.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * 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.
 *    * Neither the name of the auhor 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 COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS 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 AUTHOR 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.
 */

#ifndef _RING_H
#define _RING_H

#include <stdint.h>

typedef int32_t ring_size_t;

typedef struct ring {
    uint8_t *data;
    ring_size_t size;
    uint32_t begin;
    uint32_t end;
} ring_t;

#define RING_SIZE(RING)  ((RING)->size - 1)
#define RING_DATA(RING)  (RING)->data
#define RING_EMPTY(RING) ((RING)->begin == (RING)->end)

void ring_init(ring_t *ring, uint8_t *buf, ring_size_t size);
int32_t ring_write_ch(ring_t *ring, uint8_t ch);
int32_t ring_write(ring_t *ring, uint8_t *data, ring_size_t size);
int32_t ring_read_ch(ring_t *ring, uint8_t *ch);
int32_t ring_read(ring_t *ring, uint8_t *data, ring_size_t size);
int32_t ring_read_contineous(ring_t *ring, uint8_t **data, ring_size_t maxlen);
uint32_t ring_mark(ring_t *ring);
uint32_t ring_marklen(ring_t *ring, uint32_t mark);
void ring_skip_line(struct ring *ring);

#endif /* _RING_H */