circularqueue.c

这是一个进程通信和手机数据处理程序, 与以前发的手机界面一起构成一个简单手机系统,是我们做的第一个版本,供大家一起学习

#include "MySHM.h"

#define MAXVAL  100 

/* Definition of circular queue's struct */
typedef struct
{ 
	int   d[MAXVAL]; 
	int   front; 
	int	rear; 
}CirQUEUE;  
CirQUEUE cQ_InBox,cQ_OutBox; 

/* Initial the empty circular queue */
void INITQUEUE( SOURCETYPE sType ) 
{
	if( sType == INBOX )
	{
		cQ_InBox.front = cQ_InBox.rear = MAXVAL-1;
	}
	else if( sType == OUTBOX)
	{
		cQ_OutBox.front = cQ_OutBox.rear = MAXVAL-1;

	}
}

/* Data element Enter the circular queue */
int ENQUEUE ( SOURCETYPE sType, int element )
{ 
	if( sType == INBOX)
	{
		if ( cQ_InBox.front == (cQ_InBox.rear+1) % MAXVAL ) //Fail to enter for the full queue
			return 0;
		else					     //Successfully enter the queue
		{ 
			cQ_InBox.rear = (cQ_InBox.rear+1) % MAXVAL; 
			cQ_InBox.d[cQ_InBox.rear] = element;  
 			return 1 ; 
		}
	}
	else if( sType == OUTBOX)
	{
		if ( cQ_OutBox.front == (cQ_OutBox.rear+1) % MAXVAL ) //Fail to enter for the full queue
			return 0;
		else					     //Successfully enter the queue
		{ 
			cQ_OutBox.rear = (cQ_OutBox.rear+1) % MAXVAL; 
			cQ_OutBox.d[cQ_OutBox.rear] = element;  
 			return 1 ; 
		}
	
	} 
}

/* Get the Data element from circular queue */
int DEQUEUE( SOURCETYPE sType )
{ 
	if( sType == INBOX)
	{
		if( cQ_InBox.front == cQ_InBox.rear ) 		//Fail to get data for the empty queue
			return 0;
		else
		{ 
			cQ_InBox.front = ( cQ_InBox.front+1) % MAXVAL ;
			printf( "Dequeue %d\n",cQ_InBox.d[cQ_InBox.front] );
			return ( cQ_InBox.d[cQ_InBox.front] ) ;
		}
	}
	else if( sType == OUTBOX)
	{
		if( cQ_OutBox.front == cQ_OutBox.rear ) 		//Fail to get data for the empty queue
			return 0;
		else
		{ 
			cQ_OutBox.front = ( cQ_OutBox.front+1) % MAXVAL ;
			printf( "Dequeue %d\n",cQ_OutBox.d[cQ_OutBox.front] );
			return ( cQ_OutBox.d[cQ_OutBox.front] ) ;
		}

	}
	  	
}