122 lines
2.7 KiB
C
122 lines
2.7 KiB
C
/* $OpenBSD: queue.c,v 1.4 2003/06/25 05:31:11 deraadt Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
/*
|
|
* A really poor man's queue. It does only what it has to and gets out of
|
|
* Dodge.
|
|
*/
|
|
|
|
#include <sys/param.h>
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "grep.h"
|
|
|
|
typedef struct queue {
|
|
struct queue *next;
|
|
str_t data;
|
|
} queue_t;
|
|
|
|
static queue_t *q_head, *q_tail;
|
|
static int count;
|
|
|
|
static queue_t *dequeue(void);
|
|
|
|
void
|
|
initqueue(void)
|
|
{
|
|
q_head = q_tail = NULL;
|
|
}
|
|
|
|
static void
|
|
free_item(queue_t *item)
|
|
{
|
|
free(item);
|
|
}
|
|
|
|
void
|
|
enqueue(str_t *x)
|
|
{
|
|
queue_t *item;
|
|
|
|
item = grep_malloc(sizeof *item + x->len);
|
|
item->data.len = x->len;
|
|
item->data.line_no = x->line_no;
|
|
item->data.off = x->off;
|
|
item->data.dat = (char *)item + sizeof *item;
|
|
memcpy(item->data.dat, x->dat, x->len);
|
|
item->data.file = x->file;
|
|
item->next = NULL;
|
|
|
|
if (!q_head) {
|
|
q_head = q_tail = item;
|
|
} else {
|
|
q_tail->next = item;
|
|
q_tail = item;
|
|
}
|
|
|
|
if (++count > Bflag)
|
|
free_item(dequeue());
|
|
}
|
|
|
|
static queue_t *
|
|
dequeue(void)
|
|
{
|
|
queue_t *item;
|
|
|
|
if (q_head == NULL)
|
|
return NULL;
|
|
|
|
--count;
|
|
item = q_head;
|
|
q_head = item->next;
|
|
if (q_head == NULL)
|
|
q_tail = NULL;
|
|
return item;
|
|
}
|
|
|
|
void
|
|
printqueue(void)
|
|
{
|
|
queue_t *item;
|
|
|
|
while ((item = dequeue()) != NULL) {
|
|
printline(&item->data, '-');
|
|
free_item(item);
|
|
}
|
|
}
|
|
|
|
void
|
|
clearqueue(void)
|
|
{
|
|
queue_t *item;
|
|
|
|
while ((item = dequeue()) != NULL)
|
|
free_item(item);
|
|
}
|