1 /* $NetBSD: queue.c,v 1.1.1.2 2004/01/02 15:00:34 cjep Exp $ */ 2 3 /*- 4 * Copyright (c) 1999 James Howard and Dag-Erling Co�dan Sm�rgrav 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 */ 29 30 #include <sys/cdefs.h> 31 #ifndef lint 32 __RCSID("$NetBSD: queue.c,v 1.1.1.2 2004/01/02 15:00:34 cjep Exp $"); 33 #endif /* not lint */ 34 35 /* 36 * A really poor man's queue. It does only what it has to and gets out of 37 * Dodge. 38 */ 39 40 #include <sys/param.h> 41 42 #include <stdlib.h> 43 #include <string.h> 44 45 #include "grep.h" 46 47 typedef struct queue { 48 struct queue *next; 49 str_t data; 50 } queue_t; 51 52 static queue_t *q_head, *q_tail; 53 static int count; 54 55 static queue_t *dequeue(void); 56 57 void 58 initqueue(void) 59 { 60 q_head = q_tail = NULL; 61 } 62 63 static void 64 free_item(queue_t *item) 65 { 66 free(item); 67 } 68 69 void 70 enqueue(str_t *x) 71 { 72 queue_t *item; 73 74 item = grep_malloc(sizeof *item + x->len); 75 item->data.len = x->len; 76 item->data.line_no = x->line_no; 77 item->data.off = x->off; 78 item->data.dat = (char *)item + sizeof *item; 79 memcpy(item->data.dat, x->dat, x->len); 80 item->data.file = x->file; 81 item->next = NULL; 82 83 if (!q_head) { 84 q_head = q_tail = item; 85 } else { 86 q_tail->next = item; 87 q_tail = item; 88 } 89 90 if (++count > Bflag) 91 free_item(dequeue()); 92 } 93 94 static queue_t * 95 dequeue(void) 96 { 97 queue_t *item; 98 99 if (q_head == NULL) 100 return NULL; 101 102 --count; 103 item = q_head; 104 q_head = item->next; 105 if (q_head == NULL) 106 q_tail = NULL; 107 return item; 108 } 109 110 void 111 printqueue(void) 112 { 113 queue_t *item; 114 115 while ((item = dequeue()) != NULL) { 116 printline(&item->data, fn_dashchar, (regmatch_t *)NULL, 0); 117 free_item(item); 118 } 119 } 120 121 void 122 clearqueue(void) 123 { 124 queue_t *item; 125 126 while ((item = dequeue()) != NULL) 127 free_item(item); 128 } 129