1 /* $NetBSD: conf.c,v 1.9 2001/01/10 03:33:16 lukem Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This code is derived from software donated to Berkeley by 8 * Jan-Simon Pendry. 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * from: Id: conf.c,v 1.2 1992/05/27 07:09:27 jsp Exp 39 * @(#)conf.c 8.2 (Berkeley) 3/27/94 40 */ 41 42 #include <sys/cdefs.h> 43 #ifndef lint 44 __RCSID("$NetBSD: conf.c,v 1.9 2001/01/10 03:33:16 lukem Exp $"); 45 #endif /* not lint */ 46 47 #include <sys/types.h> 48 #include <sys/param.h> 49 #include <sys/syslog.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <unistd.h> 53 #include <string.h> 54 #include <errno.h> 55 #include <limits.h> 56 #include <regex.h> 57 58 #include "portald.h" 59 60 #define ALLOC(ty) (xmalloc(sizeof(ty))) 61 62 typedef struct path path; 63 struct path { 64 qelem p_q; /* 2-way linked list */ 65 int p_lno; /* Line number of this record */ 66 char *p_args; /* copy of arg string (malloc) */ 67 char *p_key; /* Pathname to match (also p_argv[0]) */ 68 regex_t p_re; /* RE to match against pathname (malloc) */ 69 int p_use_re; /* true if entry is RE */ 70 int p_argc; /* number of elements in arg string */ 71 char **p_argv; /* argv[] pointers into arg string (malloc) */ 72 }; 73 74 static void ins_que __P((qelem *, qelem *)); 75 static path *palloc __P((char *, int, const char *)); 76 static void pfree __P((path *)); 77 static int pinsert __P((path *, qelem *)); 78 static void preplace __P((qelem *, qelem *)); 79 static void readfp __P((qelem *, FILE *, const char *)); 80 static void rem_que __P((qelem *)); 81 static void *xmalloc __P((size_t)); 82 83 /* 84 * Add an element to a 2-way list, 85 * just after (pred) 86 */ 87 static void 88 ins_que(elem, pred) 89 qelem *elem, *pred; 90 { 91 qelem *p = pred->q_forw; 92 elem->q_back = pred; 93 elem->q_forw = p; 94 pred->q_forw = elem; 95 p->q_back = elem; 96 } 97 98 /* 99 * Remove an element from a 2-way list 100 */ 101 static void 102 rem_que(elem) 103 qelem *elem; 104 { 105 qelem *p = elem->q_forw; 106 qelem *p2 = elem->q_back; 107 p2->q_forw = p; 108 p->q_back = p2; 109 } 110 111 /* 112 * Error checking malloc 113 */ 114 static void * 115 xmalloc(siz) 116 size_t siz; 117 { 118 void *p = malloc(siz); 119 if (p) 120 return (p); 121 syslog(LOG_ERR, "malloc: failed to get %lu bytes", (u_long)siz); 122 exit(1); 123 } 124 125 /* 126 * Insert the path in the list. 127 * If there is already an element with the same key then 128 * the *second* one is ignored (return 0). If the key is 129 * not found then the path is added to the end of the list 130 * and 1 is returned. 131 */ 132 static int 133 pinsert(p0, q0) 134 path *p0; 135 qelem *q0; 136 { 137 qelem *q; 138 139 if (p0->p_argc == 0) 140 return (0); 141 142 for (q = q0->q_forw; q != q0; q = q->q_forw) { 143 path *p = (path *) q; 144 if (strcmp(p->p_key, p0->p_key) == 0) 145 return (0); 146 } 147 ins_que(&p0->p_q, q0->q_back); 148 return (1); 149 150 } 151 152 static path * 153 palloc(cline, lno, conf_file) 154 char *cline; 155 int lno; 156 const char *conf_file; 157 { 158 int c, errcode; 159 char *s; 160 char *key; 161 path *p; 162 char **ap; 163 164 /* 165 * Implement comment chars 166 */ 167 s = strchr(cline, '#'); 168 if (s) 169 *s = 0; 170 171 /* 172 * Do a pass through the string to count the number 173 * of arguments 174 */ 175 c = 0; 176 key = strdup(cline); 177 for (s = key; s != NULL; ) { 178 char *val; 179 while ((val = strsep(&s, " \t\n")) != NULL && *val == '\0') 180 ; 181 if (val) 182 c++; 183 } 184 c++; 185 free(key); 186 187 if (c <= 1) 188 return (0); 189 190 /* 191 * Now do another pass and generate a new path structure 192 */ 193 p = ALLOC(path); 194 p->p_argc = 0; 195 p->p_argv = xmalloc(c * sizeof(char *)); 196 p->p_args = strdup(cline); 197 ap = p->p_argv; 198 for (s = p->p_args; s != NULL; ) { 199 char *val; 200 while ((val = strsep(&s, " \t\n")) != NULL && *val == '\0') 201 ; 202 if (val) { 203 *ap++ = val; 204 p->p_argc++; 205 } 206 } 207 *ap = 0; 208 209 #ifdef DEBUG 210 for (c = 0; c < p->p_argc; c++) 211 printf("%sv[%d] = %s\n", c?"\t":"", c, p->p_argv[c]); 212 #endif 213 214 p->p_key = p->p_argv[0]; 215 p->p_use_re = 0; 216 if (strpbrk(p->p_key, RE_CHARS)) { 217 errcode = regcomp(&p->p_re, p->p_key, REG_EXTENDED|REG_NOSUB); 218 if (errcode == 0) 219 p->p_use_re = 1; 220 else { 221 char buf[200]; 222 regerror(errcode, &p->p_re, buf, sizeof(buf)); 223 224 syslog(LOG_WARNING, "%s, line %d: regcomp \"%s\": %s", 225 conf_file, p->p_lno, p->p_key, buf); 226 } 227 } 228 p->p_lno = lno; 229 230 return (p); 231 } 232 233 /* 234 * Free a path structure 235 */ 236 static void 237 pfree(p) 238 path *p; 239 { 240 free(p->p_args); 241 free((char *) p->p_argv); 242 if (p->p_use_re) 243 regfree(&p->p_re); 244 free((char *) p); 245 } 246 247 /* 248 * Discard all currently held path structures on q0. 249 * and add all the ones on xq. 250 */ 251 static void 252 preplace(q0, xq) 253 qelem *q0; 254 qelem *xq; 255 { 256 /* 257 * While the list is not empty, 258 * take the first element off the list 259 * and free it. 260 */ 261 while (q0->q_forw != q0) { 262 qelem *q = q0->q_forw; 263 rem_que(q); 264 pfree((path *) q); 265 } 266 while (xq->q_forw != xq) { 267 qelem *q = xq->q_forw; 268 rem_que(q); 269 ins_que(q, q0); 270 } 271 } 272 273 /* 274 * Read the lines from the configuration file and 275 * add them to the list of paths. 276 */ 277 static void 278 readfp(q0, fp, conf_file) 279 qelem *q0; 280 FILE *fp; 281 const char *conf_file; 282 { 283 char cline[LINE_MAX]; 284 int nread = 0; 285 qelem q; 286 287 /* 288 * Make a new empty list. 289 */ 290 q.q_forw = q.q_back = &q; 291 292 /* 293 * Read the lines from the configuration file. 294 */ 295 while (fgets(cline, sizeof(cline), fp)) { 296 path *p = palloc(cline, nread+1, conf_file); 297 if (p && !pinsert(p, &q)) 298 pfree(p); 299 nread++; 300 } 301 302 /* 303 * If some records were read, then throw 304 * away the old list and replace with the 305 * new one. 306 */ 307 if (nread) 308 preplace(q0, &q); 309 } 310 311 /* 312 * Read the configuration file (conf) and replace 313 * the existing path list with the new version. 314 * If the file is not readable, then no changes take place 315 */ 316 void 317 conf_read(q, conf) 318 qelem *q; 319 char *conf; 320 { 321 FILE *fp = fopen(conf, "r"); 322 if (fp) { 323 readfp(q, fp, conf); 324 (void) fclose(fp); 325 } else 326 syslog(LOG_WARNING, "open config file \"%s\": %m", conf); 327 } 328 329 330 char ** 331 conf_match(q0, key) 332 qelem *q0; 333 char *key; 334 { 335 qelem *q; 336 337 for (q = q0->q_forw; q != q0; q = q->q_forw) { 338 path *p = (path *) q; 339 if (p->p_use_re) { 340 if (regexec(&p->p_re, key, 0, NULL, 0) == 0) 341 return (p->p_argv+1); 342 } else { 343 if (strncmp(p->p_key, key, strlen(p->p_key)) == 0) 344 return (p->p_argv+1); 345 } 346 } 347 348 return (0); 349 } 350