static int
_pop_queue(ttyQueue *queue)
{
if (_is_empty_queue(queue)) return -1;
int ret = queue->tq_buf[queue->tq_tail];
if (++queue->tq_tail == QUEUE_LEN)
queue->tq_tail = 0;
return ret;
}
static int
_backspace_queue(ttyQueue *queue)
{
if (_is_empty_queue(queue)) return -1;
int prehead = queue->tq_head - 1;
if (prehead == -1)
prehead = QUEUE_LEN - 1;
char lc = queue->tq_buf[prehead];
if (lc == '\r') return -1;
queue->tq_head = prehead;
return 0;
}
int
tty_read(char *buf, int cnt)
{
int i = 0;
if (_is_empty_queue(&console_tty.td_read_q)) {
console_tty.td_read_q.tq_wait_task = current_task();
sleep(console_tty.td_read_q.tq_wait_task);
}
while(i < cnt) {
if (_is_empty_queue(&console_tty.td_read_q)) {
console_tty.td_read_q.tq_wait_task = current_task();
sleep(console_tty.td_read_q.tq_wait_task);
}
buf[i] = (char)_pop_queue(&console_tty.td_read_q);
if (buf[i] == '\r')
break;
++i;
}
return i + 1;
}
HuffMan * creat_huffman_tree(Queue * head){
HuffMan * right;
HuffMan * left;
HuffMan * current;
while ( !_is_empty_queue(head) ) {
left = delete_Queue(head);
right = delete_Queue(head);
current = (HuffMan *)malloc(sizeof(HuffMan));
current -> weight = left -> weight + right -> weight;
current -> left_child = left;
current -> right_child = right;
order_Enter_Queue(head, current);
}
return head -> front -> next -> data;
}
