1 /* $NetBSD: queue.c,v 1.5 2011/08/31 16:24:57 plunky Exp $ */ 2 /* $FreeBSD$ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 6 * 7 * Copyright (c) 1999 James Howard and Dag-Erling Coïdan Smørgrav 8 * All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /* 33 * A really poor man's queue. It does only what it has to and gets out of 34 * Dodge. It is used in place of <sys/queue.h> to get a better performance. 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <sys/param.h> 41 #include <sys/queue.h> 42 43 #include <stdlib.h> 44 #include <string.h> 45 46 #include "grep.h" 47 48 struct qentry { 49 STAILQ_ENTRY(qentry) list; 50 struct str data; 51 }; 52 53 static STAILQ_HEAD(, qentry) queue = STAILQ_HEAD_INITIALIZER(queue); 54 static long long count; 55 56 static struct qentry *dequeue(void); 57 58 /* 59 * Enqueue another line; return true if we've dequeued a line as a result 60 */ 61 bool 62 enqueue(struct str *x) 63 { 64 struct qentry *item; 65 66 item = grep_malloc(sizeof(struct qentry)); 67 item->data.dat = grep_malloc(sizeof(char) * x->len); 68 item->data.len = x->len; 69 item->data.line_no = x->line_no; 70 item->data.boff = x->boff; 71 item->data.off = x->off; 72 memcpy(item->data.dat, x->dat, x->len); 73 item->data.file = x->file; 74 75 STAILQ_INSERT_TAIL(&queue, item, list); 76 77 if (++count > Bflag) { 78 item = dequeue(); 79 free(item->data.dat); 80 free(item); 81 return (true); 82 } 83 return (false); 84 } 85 86 static struct qentry * 87 dequeue(void) 88 { 89 struct qentry *item; 90 91 item = STAILQ_FIRST(&queue); 92 if (item == NULL) 93 return (NULL); 94 95 STAILQ_REMOVE_HEAD(&queue, list); 96 --count; 97 return (item); 98 } 99 100 void 101 printqueue(void) 102 { 103 struct qentry *item; 104 105 while ((item = dequeue()) != NULL) { 106 grep_printline(&item->data, '-'); 107 free(item->data.dat); 108 free(item); 109 } 110 } 111 112 void 113 clearqueue(void) 114 { 115 struct qentry *item; 116 117 while ((item = dequeue()) != NULL) { 118 free(item->data.dat); 119 free(item); 120 } 121 } 122