freebsd-skq/usr.bin/grep/queue.c
2010-08-19 09:28:59 +00:00

105 lines
2.7 KiB
C

/*-
* 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. It is used in place of <sys/queue.h> to get a better performance.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/queue.h>
#include <stdlib.h>
#include <string.h>
#include "grep.h"
struct qentry {
STAILQ_ENTRY(qentry) list;
struct str data;
};
static STAILQ_HEAD(, qentry) queue = STAILQ_HEAD_INITIALIZER(queue);
static unsigned long long count;
static struct qentry *dequeue(void);
void
enqueue(struct str *x)
{
struct qentry *item;
item = grep_malloc(sizeof(struct qentry));
item->data.dat = grep_malloc(sizeof(char) * x->len);
item->data.len = x->len;
item->data.line_no = x->line_no;
item->data.off = x->off;
memcpy(item->data.dat, x->dat, x->len);
item->data.file = x->file;
STAILQ_INSERT_TAIL(&queue, item, list);
if (++count > Bflag)
free(dequeue());
}
static struct qentry *
dequeue(void)
{
struct qentry *item;
item = STAILQ_FIRST(&queue);
if (item == NULL)
return (NULL);
STAILQ_REMOVE_HEAD(&queue, list);
--count;
return (item);
}
void
printqueue(void)
{
struct qentry *item;
while ((item = dequeue()) != NULL) {
printline(&item->data, '-', (regmatch_t *)NULL, 0);
free(item);
}
}
void
clearqueue(void)
{
struct qentry *item;
while ((item = dequeue()) != NULL)
free(item);
}