1 /* $NetBSD: fparseln.c,v 1.10 2009/10/21 01:07:45 snj Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Christos Zoulas. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 #if defined(LIBC_SCCS) && !defined(lint) 29 __RCSID("$NetBSD: fparseln.c,v 1.10 2009/10/21 01:07:45 snj Exp $"); 30 #endif /* LIBC_SCCS and not lint */ 31 32 #include "namespace.h" 33 34 #include <assert.h> 35 #include <errno.h> 36 #include <stdio.h> 37 #include <string.h> 38 #include <stdlib.h> 39 40 #ifdef __weak_alias 41 __weak_alias(fparseln,_fparseln) 42 #endif 43 44 #if ! HAVE_FPARSELN || BROKEN_FPARSELN 45 46 #ifndef HAVE_NBTOOL_CONFIG_H 47 #include "reentrant.h" 48 #include "local.h" 49 #else 50 #define FLOCKFILE(fp) 51 #define FUNLOCKFILE(fp) 52 #endif 53 54 #if defined(_REENTRANT) && !HAVE_NBTOOL_CONFIG_H 55 #define __fgetln(f, l) __fgetstr(f, l, '\n') 56 #else 57 #define __fgetln(f, l) fgetln(f, l) 58 #endif 59 60 static int isescaped(const char *, const char *, int); 61 62 /* isescaped(): 63 * Return true if the character in *p that belongs to a string 64 * that starts in *sp, is escaped by the escape character esc. 65 */ 66 static int 67 isescaped(const char *sp, const char *p, int esc) 68 { 69 const char *cp; 70 size_t ne; 71 72 _DIAGASSERT(sp != NULL); 73 _DIAGASSERT(p != NULL); 74 75 /* No escape character */ 76 if (esc == '\0') 77 return 0; 78 79 /* Count the number of escape characters that precede ours */ 80 for (ne = 0, cp = p; --cp >= sp && *cp == esc; ne++) 81 continue; 82 83 /* Return true if odd number of escape characters */ 84 return (ne & 1) != 0; 85 } 86 87 88 /* fparseln(): 89 * Read a line from a file parsing continuations ending in \ 90 * and eliminating trailing newlines, or comments starting with 91 * the comment char. 92 */ 93 char * 94 fparseln(FILE *fp, size_t *size, size_t *lineno, const char str[3], int flags) 95 { 96 static const char dstr[3] = { '\\', '\\', '#' }; 97 98 size_t s, len; 99 char *buf; 100 char *ptr, *cp; 101 int cnt; 102 char esc, con, nl, com; 103 104 _DIAGASSERT(fp != NULL); 105 106 len = 0; 107 buf = NULL; 108 cnt = 1; 109 110 if (str == NULL) 111 str = dstr; 112 113 esc = str[0]; 114 con = str[1]; 115 com = str[2]; 116 /* 117 * XXX: it would be cool to be able to specify the newline character, 118 * but unfortunately, fgetln does not let us 119 */ 120 nl = '\n'; 121 122 FLOCKFILE(fp); 123 124 while (cnt) { 125 cnt = 0; 126 127 if (lineno) 128 (*lineno)++; 129 130 if ((ptr = __fgetln(fp, &s)) == NULL) 131 break; 132 133 if (s && com) { /* Check and eliminate comments */ 134 for (cp = ptr; cp < ptr + s; cp++) 135 if (*cp == com && !isescaped(ptr, cp, esc)) { 136 s = cp - ptr; 137 cnt = s == 0 && buf == NULL; 138 break; 139 } 140 } 141 142 if (s && nl) { /* Check and eliminate newlines */ 143 cp = &ptr[s - 1]; 144 145 if (*cp == nl) 146 s--; /* forget newline */ 147 } 148 149 if (s && con) { /* Check and eliminate continuations */ 150 cp = &ptr[s - 1]; 151 152 if (*cp == con && !isescaped(ptr, cp, esc)) { 153 s--; /* forget continuation char */ 154 cnt = 1; 155 } 156 } 157 158 if (s == 0) { 159 /* 160 * nothing to add, skip realloc except in case 161 * we need a minimal buf to return an empty line 162 */ 163 if (cnt || buf != NULL) 164 continue; 165 } 166 167 if ((cp = realloc(buf, len + s + 1)) == NULL) { 168 FUNLOCKFILE(fp); 169 free(buf); 170 return NULL; 171 } 172 buf = cp; 173 174 (void) memcpy(buf + len, ptr, s); 175 len += s; 176 buf[len] = '\0'; 177 } 178 179 FUNLOCKFILE(fp); 180 181 if ((flags & FPARSELN_UNESCALL) != 0 && esc && buf != NULL && 182 strchr(buf, esc) != NULL) { 183 ptr = cp = buf; 184 while (cp[0] != '\0') { 185 int skipesc; 186 187 while (cp[0] != '\0' && cp[0] != esc) 188 *ptr++ = *cp++; 189 if (cp[0] == '\0' || cp[1] == '\0') 190 break; 191 192 skipesc = 0; 193 if (cp[1] == com) 194 skipesc += (flags & FPARSELN_UNESCCOMM); 195 if (cp[1] == con) 196 skipesc += (flags & FPARSELN_UNESCCONT); 197 if (cp[1] == esc) 198 skipesc += (flags & FPARSELN_UNESCESC); 199 if (cp[1] != com && cp[1] != con && cp[1] != esc) 200 skipesc = (flags & FPARSELN_UNESCREST); 201 202 if (skipesc) 203 cp++; 204 else 205 *ptr++ = *cp++; 206 *ptr++ = *cp++; 207 } 208 *ptr = '\0'; 209 len = strlen(buf); 210 } 211 212 if (size) 213 *size = len; 214 return buf; 215 } 216 217 #ifdef TEST 218 219 int main(int, char **); 220 221 int 222 main(int argc, char **argv) 223 { 224 char *ptr; 225 size_t size, line; 226 227 line = 0; 228 while ((ptr = fparseln(stdin, &size, &line, NULL, 229 FPARSELN_UNESCALL)) != NULL) 230 printf("line %d (%d) |%s|\n", line, size, ptr); 231 return 0; 232 } 233 234 /* 235 236 # This is a test 237 line 1 238 line 2 \ 239 line 3 # Comment 240 line 4 \# Not comment \\\\ 241 242 # And a comment \ 243 line 5 \\\ 244 line 6 245 246 */ 247 248 #endif /* TEST */ 249 #endif /* ! HAVE_FPARSELN || BROKEN_FPARSELN */ 250
Indexes created Tue Sep 30 07:10:03 GMT 2025