/*
 * queue.c
 * Description:
 *
 *  Created on: 2014-11-13
 *      Author: Graydon
 *  Modify:
 */

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <string.h>
#include "drv/hmem.h"
#include "queue.h"

typedef struct{
	int wr;
	int rd;
	int len;
	int count;
	int lock;
	char data[4];
}tag_queue,*ptag_queue;




void* queue_create(int size)
{
	ptag_queue q = malloc(size+(sizeof(tag_queue)-4));
	assert(q!=0);

	q->len = size;
	q->wr=q->rd=0;
	q->count =0;
	q->lock =0;
	return q;
}


int queue_push(void* queue, const void* data, int size )
{
	ptag_queue q = queue;

	memcpy(q->data+q->wr,data,size);
	q->wr+=size;
	if(q->wr>=q->len){
		q->wr=0;
	}
	
	q->count+=size;

	return size;
}


int queue_count(void* queue)
{
	ptag_queue q = queue;
	
	return q->count;
}


int queue_pop(void* queue,void* data, int size)
{
	ptag_queue q = queue;

	memcpy(data,q->data+q->rd,size);
	q->rd+=size;
	if(q->rd>=q->len){
		q->rd = 0;
	}

	q->count-=size;
	
	return size;
}



void queue_destroy(void* queue)
{
	free(queue);
}