#ifndef _MESA_SHM_RING_QUEUE_H_
#define _MESA_SHM_RING_QUEUE_H_

#include <pthread.h>
#define MESA_SHM_RING_QUEUE_NUM     128
#define MESA_SHM_RING_QUEUE_BLOCK_NUM     8192
#define MESA_SHM_RING_QUEUE_BLOCK_BUFLEN  4096
#define MESA_SHM_RING_QUEUE_BLOCK_SIZE    (MESA_SHM_RING_QUEUE_BLOCK_BUFLEN + sizeof(int) + 1)  /*user buf + (int)len flag + '\n'*/
#define MESA_SHM_KEY_OVERVIEW         35720
#define MESA_SHM_KEY_MIN              (MESA_SHM_KEY_OVERVIEW + 1)   
#define MESA_SHM_KEY_MAX              (MESA_SHM_KEY_MIN + MESA_SHM_RING_QUEUE_NUM -1)

#define MESA_SHM_RING_QUEUE_INITIAL      0
#define MESA_SHM_RING_QUEUE_IDLE         1
#define MESA_SHM_RING_QUEUE_HALF_IDLE    2
#define MESA_SHM_RING_QUEUE_USED         3

struct MESA_shm_overview *MESA_shm_alloc_overview();
struct MESA_shm_queue_head *MESA_shm_get_ring_queue();
void MESA_shm_init_mutex();
void MESA_shm_init_overview();
void MESA_shm_recycle_ring_queue(struct MESA_shm_queue_head *ring_queue_head);
int MESA_shm_copy_buf_to_ring_queue(char *buf, int buflen, struct MESA_shm_queue_head *head);
void MESA_shm_write_ring_queue_to_file(int fd, struct MESA_shm_queue_head *head);



struct MESA_shm_overview{
	int shmkey;
	int shmid;
	int idx;
	pthread_mutex_t mutex;
};

struct MESA_shm_queue_head{
	unsigned int blksize;
	unsigned int blknum;
	volatile unsigned int rd_idx;
	volatile unsigned int wr_idx;
	int ovw_idx;
};

#endif