/*
 * Copyright (c) 2023 Institute of Parallel And Distributed Systems (IPADS), Shanghai Jiao Tong University (SJTU)
 * Licensed under the Mulan PSL v2.
 * You can use this software according to the terms and conditions of the Mulan PSL v2.
 * You may obtain a copy of Mulan PSL v2 at:
 *     http://license.coscl.org.cn/MulanPSL2
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT, MERCHANTABILITY OR FIT FOR A PARTICULAR
 * PURPOSE.
 * See the Mulan PSL v2 for more details.
 */
#ifndef LIB_RING_BUFFER_H
#define LIB_RING_BUFFER_H

#include <common/types.h>

#define RING_BUFFER_FULL     1
#define RING_BUFFER_NOT_FULL 0
#define MSG_OP_SUCCESS       1
#define MSG_OP_FAILURE       0

/*
 * Ring buffer struct layout
 * buffer_size: size_t, size of whole struct including the meta data
 * consumer_offset: int
 * producer_offset: int
 * msg_size: size_t, size of the msg that will be stored in the buffer
 * There is also a data buffer to actually store data, closely after the meta data above.
 */

struct ring_buffer {
    size_t buffer_size;
    off_t consumer_offset;
    off_t producer_offset;
    size_t msg_size;
};

int get_one_msg(struct ring_buffer *ring_buf, void *msg);
int set_one_msg(struct ring_buffer *ring_buf, void *msg);
int if_buffer_full(struct ring_buffer *ring_buf);

#endif /* LIB_RING_BUFFER_H */