str.c revision 3983
1/*- 2 * Copyright (c) 1991, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#ifndef lint 35static char sccsid[] = "@(#)str.c 8.1 (Berkeley) 6/6/93"; 36#endif /* not lint */ 37 38#include <sys/cdefs.h> 39#include <sys/types.h> 40 41#include <errno.h> 42#include <stddef.h> 43#include <stdio.h> 44#include <stdlib.h> 45#include <string.h> 46 47#include "extern.h" 48 49static int backslash __P((STR *)); 50static int bracket __P((STR *)); 51static int c_class __P((const void *, const void *)); 52static void genclass __P((STR *)); 53static void genequiv __P((STR *)); 54static int genrange __P((STR *)); 55static void genseq __P((STR *)); 56 57int 58next(s) 59 register STR *s; 60{ 61 register int ch; 62 63 switch (s->state) { 64 case EOS: 65 return (0); 66 case INFINITE: 67 return (1); 68 case NORMAL: 69 switch (ch = *s->str) { 70 case '\0': 71 s->state = EOS; 72 return (0); 73 case '\\': 74 s->lastch = backslash(s); 75 break; 76 case '[': 77 if (bracket(s)) 78 return (next(s)); 79 /* FALLTHROUGH */ 80 default: 81 ++s->str; 82 s->lastch = ch; 83 break; 84 } 85 86 /* We can start a range at any time. */ 87 if (s->str[0] == '-' && genrange(s)) 88 return (next(s)); 89 return (1); 90 case RANGE: 91 if (s->cnt-- == 0) { 92 s->state = NORMAL; 93 return (next(s)); 94 } 95 ++s->lastch; 96 return (1); 97 case SEQUENCE: 98 if (s->cnt-- == 0) { 99 s->state = NORMAL; 100 return (next(s)); 101 } 102 return (1); 103 case SET: 104 if ((s->lastch = s->set[s->cnt++]) == OOBCH) { 105 s->state = NORMAL; 106 return (next(s)); 107 } 108 return (1); 109 } 110 /* NOTREACHED */ 111} 112 113static int 114bracket(s) 115 register STR *s; 116{ 117 register char *p; 118 119 switch (s->str[1]) { 120 case ':': /* "[:class:]" */ 121 if ((p = strstr(s->str + 2, ":]")) == NULL) 122 return (0); 123 *p = '\0'; 124 s->str += 2; 125 genclass(s); 126 s->str = p + 2; 127 return (1); 128 case '=': /* "[=equiv=]" */ 129 if ((p = strstr(s->str + 2, "=]")) == NULL) 130 return (0); 131 s->str += 2; 132 genequiv(s); 133 return (1); 134 default: /* "[\###*n]" or "[#*n]" */ 135 if ((p = strpbrk(s->str + 2, "*]")) == NULL) 136 return (0); 137 if (p[0] != '*' || index(p, ']') == NULL) 138 return (0); 139 s->str += 1; 140 genseq(s); 141 return (1); 142 } 143 /* NOTREACHED */ 144} 145 146int isalnum __P((int)), 147 isalpha __P((int)), 148 isblank __P((int)), 149 isspace __P((int)), 150 iscntrl __P((int)), 151 isdigit __P((int)), 152 isgraph __P((int)), 153 islower __P((int)), 154 isprint __P((int)), 155 ispunct __P((int)), 156 isupper __P((int)), 157 isxdigit __P((int)); 158 159typedef struct { 160 char *name; 161 int (*func) __P((int)); 162 int *set; 163} CLASS; 164 165static CLASS classes[] = { 166 { "alnum", isalnum, }, 167 { "alpha", isalpha, }, 168 { "blank", isblank, }, 169 { "cntrl", iscntrl, }, 170 { "digit", isdigit, }, 171 { "graph", isgraph, }, 172 { "lower", islower, }, 173 { "print", isprint, }, 174 { "punct", ispunct, }, 175 { "space", isspace, }, 176 { "upper", isupper, }, 177 { "xdigit", isxdigit, }, 178}; 179 180static void 181genclass(s) 182 STR *s; 183{ 184 register int cnt, (*func) __P((int)); 185 CLASS *cp, tmp; 186 int *p; 187 188 tmp.name = s->str; 189 if ((cp = (CLASS *)bsearch(&tmp, classes, sizeof(classes) / 190 sizeof(CLASS), sizeof(CLASS), c_class)) == NULL) 191 err("unknown class %s", s->str); 192 193 if ((cp->set = p = malloc((NCHARS + 1) * sizeof(int))) == NULL) 194 err("%s", strerror(errno)); 195 bzero(p, (NCHARS + 1) * sizeof(int)); 196 for (cnt = 0, func = cp->func; cnt < NCHARS; ++cnt) 197 if ((func)(cnt)) 198 *p++ = cnt; 199 *p = OOBCH; 200 201 s->cnt = 0; 202 s->state = SET; 203 s->set = cp->set; 204} 205 206static int 207c_class(a, b) 208 const void *a, *b; 209{ 210 return (strcmp(((CLASS *)a)->name, ((CLASS *)b)->name)); 211} 212 213/* 214 * English doesn't have any equivalence classes, so for now 215 * we just syntax check and grab the character. 216 */ 217static void 218genequiv(s) 219 STR *s; 220{ 221 if (*s->str == '\\') { 222 s->equiv[0] = backslash(s); 223 if (*s->str != '=') 224 err("misplaced equivalence equals sign"); 225 } else { 226 s->equiv[0] = s->str[0]; 227 if (s->str[1] != '=') 228 err("misplaced equivalence equals sign"); 229 } 230 s->str += 2; 231 s->cnt = 0; 232 s->state = SET; 233 s->set = s->equiv; 234} 235 236static int 237genrange(s) 238 STR *s; 239{ 240 int stopval; 241 char *savestart; 242 243 savestart = s->str; 244 stopval = *++s->str == '\\' ? backslash(s) : *s->str; 245 if (stopval < s->lastch) { 246 s->str = savestart; 247 return (0); 248 } 249 s->cnt = stopval - s->lastch + 1; 250 s->state = RANGE; 251 --s->lastch; 252 return (1); 253} 254 255static void 256genseq(s) 257 STR *s; 258{ 259 char *ep; 260 261 if (s->which == STRING1) 262 err("sequences only valid in string2"); 263 264 if (*s->str == '\\') 265 s->lastch = backslash(s); 266 else 267 s->lastch = *s->str++; 268 if (*s->str != '*') 269 err("misplaced sequence asterisk"); 270 271 switch (*++s->str) { 272 case '\\': 273 s->cnt = backslash(s); 274 break; 275 case ']': 276 s->cnt = 0; 277 ++s->str; 278 break; 279 default: 280 if (isdigit(*s->str)) { 281 s->cnt = strtol(s->str, &ep, 0); 282 if (*ep == ']') { 283 s->str = ep + 1; 284 break; 285 } 286 } 287 err("illegal sequence count"); 288 /* NOTREACHED */ 289 } 290 291 s->state = s->cnt ? SEQUENCE : INFINITE; 292} 293 294/* Use the #defines isXXX() here, DON'T use them above. */ 295#include <ctype.h> 296 297/* 298 * Translate \??? into a character. Up to 3 octal digits, if no digits either 299 * an escape code or a literal character. 300 */ 301static int 302backslash(s) 303 register STR *s; 304{ 305 register int ch, cnt, val; 306 307 for (cnt = val = 0;;) { 308 ch = *++s->str; 309 if (!isascii(ch) || !isdigit(ch)) 310 break; 311 val = val * 8 + ch - '0'; 312 if (++cnt == 3) { 313 ++s->str; 314 break; 315 } 316 } 317 if (cnt) 318 return (val); 319 if (ch != '\0') 320 ++s->str; 321 switch (ch) { 322 case 'a': /* escape characters */ 323 return ('\7'); 324 case 'b': 325 return ('\b'); 326 case 'f': 327 return ('\f'); 328 case 'n': 329 return ('\n'); 330 case 'r': 331 return ('\r'); 332 case 't': 333 return ('\t'); 334 case 'v': 335 return ('\13'); 336 case '\0': /* \" -> \ */ 337 s->state = EOS; 338 return ('\\'); 339 default: /* \x" -> x */ 340 return (ch); 341 } 342} 343