/*

* Program: buffer.h

* Purpose: Definition of the circular buffer (queue) structure and operations.

*/

#define BUFFSIZE 5

typedef struct cqueue {

int arr[BUFFSIZE], front, rear;

unsigned size;

} buffer;

int buf_init(buffer *buf)

{

buf->size = BUFFSIZE;

buf->front = buf->rear = -1;

return 1;

}

int buf_insert(buffer *buf, int data)

{

if(((buf->rear+1)%buf->size) == buf->front) // buffer FULL

return 0;

if(buf->front == -1) // buffer EMPTY

buf->rear = buf->front = 0;

else

buf->rear = ((buf->rear+1)%buf->size);

buf->arr[buf->rear] = data;

return 1;

}

int buf_delete(buffer *buf, int *data)

{

if(buf->front == -1) // buffer EMPTY

return 0;

*data = buf->arr[buf->front];

if(buf->front == buf->rear)

buf->front = buf->rear = -1;

else

buf->front = ((buf->front+1)%buf->size);

return 1;

}

void buf_destroy(buffer *buf)

{

buf->size = 0;

buf->front = buf->rear = -1;

}

void buf_display(buffer *buf)

{

int i;

for(i=buf->front; i != buf->rear; i=(i+1)%buf->size)

{

printf("%d\t", buf->arr[i]);

}

if(buf->front > -1)

printf("%d\n", buf->arr[i]);

}