1/* $NetBSD: regsub.c,v 1.11 2023/02/20 02:11:07 mrg Exp $ */ 2 3/*- 4 * Copyright (c) 2015 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32extern "C" { 33 34#include <sys/param.h> 35#include <ctype.h> 36#include <stdlib.h> 37#include <string.h> 38#include <regex.h> 39 40struct str { 41 char *s_ptr; 42 size_t s_max; 43 size_t s_len; 44 int s_fixed; 45}; 46 47#define REINCR 64 48 49static int 50addspace(struct str *s, size_t len) 51{ 52 void *v; 53 54 if (s->s_max - s->s_len > len) 55 return 0; 56 57 if (s->s_fixed) 58 return -1; 59 60 s->s_max += len + REINCR; 61 62 v = realloc(s->s_ptr, s->s_max); 63 if (v == NULL) 64 return -1; 65 s->s_ptr = (char *)v; 66 67 return 0; 68} 69 70static void 71addchar(struct str *s, int c) 72{ 73 if (addspace(s, 1) == -1) 74 s->s_len++; 75 else 76 s->s_ptr[s->s_len++] = c; 77 if (c == 0) { 78 --s->s_len; 79 s->s_ptr[s->s_max - 1] = c; 80 } 81} 82 83static void 84addnstr(struct str *s, const char *buf, size_t len) 85{ 86 if (addspace(s, len) != -1) 87 memcpy(s->s_ptr + s->s_len, buf, len); 88 s->s_len += len; 89} 90 91static int 92initstr(struct str *s, char *buf, size_t len) 93{ 94 s->s_max = len; 95 s->s_ptr = (char *)(buf == NULL ? malloc(len) : buf); 96 s->s_fixed = buf != NULL; 97 s->s_len = 0; 98 return s->s_ptr == NULL ? -1 : 0; 99} 100 101static ssize_t 102regsub1(char **buf, size_t len, const char *sub, 103 const regmatch_t *rm, const char *str) 104{ 105 ssize_t i; 106 char c; 107 struct str s; 108 109 if (initstr(&s, *buf, len) == -1) 110 return -1; 111 112 while ((c = *sub++) != '\0') { 113 114 switch (c) { 115 case '&': 116 i = 0; 117 break; 118 case '\\': 119 if (isdigit((unsigned char)*sub)) 120 i = *sub++ - '0'; 121 else 122 i = -1; 123 break; 124 default: 125 i = -1; 126 break; 127 } 128 129 if (i == -1) { 130 if (c == '\\' && (*sub == '\\' || *sub == '&')) 131 c = *sub++; 132 addchar(&s, c); 133 } else if (rm[i].rm_so != -1 && rm[i].rm_eo != -1) { 134 size_t l = (size_t)(rm[i].rm_eo - rm[i].rm_so); 135 addnstr(&s, str + rm[i].rm_so, l); 136 } 137 } 138 139 addchar(&s, '\0'); 140 if (!s.s_fixed) { 141 if (s.s_len >= s.s_max) { 142 free(s.s_ptr); 143 return -1; 144 } 145 *buf = s.s_ptr; 146 } 147 return s.s_len; 148} 149 150ssize_t 151regnsub(char *buf, size_t len, const char *sub, const regmatch_t *rm, 152 const char *str) 153{ 154 return regsub1(&buf, len, sub, rm, str); 155} 156 157ssize_t 158regasub(char **buf, const char *sub, const regmatch_t *rm, const char *str) 159{ 160 *buf = NULL; 161 return regsub1(buf, REINCR, sub, rm, str); 162} 163 164} 165