str.c revision 1.6
1 /* $NetBSD: str.c,v 1.6 1994/12/07 08:35:10 jtc Exp $ */ 2 3 /*- 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. 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 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 */ 35 36 #ifndef lint 37 #if 0 38 static char sccsid[] = "@(#)str.c 8.1 (Berkeley) 6/6/93"; 39 #endif 40 static char rcsid[] = "$NetBSD: str.c,v 1.6 1994/12/07 08:35:10 jtc Exp $"; 41 #endif /* not lint */ 42 43 #include <sys/cdefs.h> 44 #include <sys/types.h> 45 46 #include <errno.h> 47 #include <stddef.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <ctype.h> 52 53 #include "extern.h" 54 55 static int backslash __P((STR *)); 56 static int bracket __P((STR *)); 57 static int c_class __P((const void *, const void *)); 58 static void genclass __P((STR *)); 59 static void genequiv __P((STR *)); 60 static int genrange __P((STR *)); 61 static void genseq __P((STR *)); 62 63 int 64 next(s) 65 register STR *s; 66 { 67 register int ch; 68 69 switch (s->state) { 70 case EOS: 71 return (0); 72 case INFINITE: 73 return (1); 74 case NORMAL: 75 switch (ch = *s->str) { 76 case '\0': 77 s->state = EOS; 78 return (0); 79 case '\\': 80 s->lastch = backslash(s); 81 break; 82 case '[': 83 if (bracket(s)) 84 return (next(s)); 85 /* FALLTHROUGH */ 86 default: 87 ++s->str; 88 s->lastch = ch; 89 break; 90 } 91 92 /* We can start a range at any time. */ 93 if (s->str[0] == '-' && genrange(s)) 94 return (next(s)); 95 return (1); 96 case RANGE: 97 if (s->cnt-- == 0) { 98 s->state = NORMAL; 99 return (next(s)); 100 } 101 ++s->lastch; 102 return (1); 103 case SEQUENCE: 104 if (s->cnt-- == 0) { 105 s->state = NORMAL; 106 return (next(s)); 107 } 108 return (1); 109 case SET: 110 if ((s->lastch = s->set[s->cnt++]) == OOBCH) { 111 s->state = NORMAL; 112 return (next(s)); 113 } 114 return (1); 115 } 116 /* NOTREACHED */ 117 } 118 119 static int 120 bracket(s) 121 register STR *s; 122 { 123 register char *p; 124 125 switch (s->str[1]) { 126 case ':': /* "[:class:]" */ 127 if ((p = strstr(s->str + 2, ":]")) == NULL) 128 return (0); 129 *p = '\0'; 130 s->str += 2; 131 genclass(s); 132 s->str = p + 2; 133 return (1); 134 case '=': /* "[=equiv=]" */ 135 if ((p = strstr(s->str + 2, "=]")) == NULL) 136 return (0); 137 s->str += 2; 138 genequiv(s); 139 return (1); 140 default: /* "[\###*n]" or "[#*n]" */ 141 if ((p = strpbrk(s->str + 2, "*]")) == NULL) 142 return (0); 143 if (p[0] != '*' || index(p, ']') == NULL) 144 return (0); 145 s->str += 1; 146 genseq(s); 147 return (1); 148 } 149 /* NOTREACHED */ 150 } 151 152 typedef struct { 153 char *name; 154 int (*func) __P((int)); 155 int *set; 156 } CLASS; 157 158 static CLASS classes[] = { 159 { "alnum", isalnum, }, 160 { "alpha", isalpha, }, 161 { "blank", isblank, }, 162 { "cntrl", iscntrl, }, 163 { "digit", isdigit, }, 164 { "graph", isgraph, }, 165 { "lower", islower, }, 166 { "print", isupper, }, 167 { "punct", ispunct, }, 168 { "space", isspace, }, 169 { "upper", isupper, }, 170 { "xdigit", isxdigit, }, 171 }; 172 173 static void 174 genclass(s) 175 STR *s; 176 { 177 register int cnt, (*func) __P((int)); 178 CLASS *cp, tmp; 179 int *p; 180 181 tmp.name = s->str; 182 if ((cp = (CLASS *)bsearch(&tmp, classes, sizeof(classes) / 183 sizeof(CLASS), sizeof(CLASS), c_class)) == NULL) 184 err("unknown class %s", s->str); 185 186 if ((cp->set = p = malloc((NCHARS + 1) * sizeof(int))) == NULL) 187 err("%s", strerror(errno)); 188 bzero(p, (NCHARS + 1) * sizeof(int)); 189 for (cnt = 0, func = cp->func; cnt < NCHARS; ++cnt) 190 if ((func)(cnt)) 191 *p++ = cnt; 192 *p = OOBCH; 193 194 s->cnt = 0; 195 s->state = SET; 196 s->set = cp->set; 197 } 198 199 static int 200 c_class(a, b) 201 const void *a, *b; 202 { 203 return (strcmp(((CLASS *)a)->name, ((CLASS *)b)->name)); 204 } 205 206 /* 207 * English doesn't have any equivalence classes, so for now 208 * we just syntax check and grab the character. 209 */ 210 static void 211 genequiv(s) 212 STR *s; 213 { 214 if (*s->str == '\\') { 215 s->equiv[0] = backslash(s); 216 if (*s->str != '=') 217 err("misplaced equivalence equals sign"); 218 } else { 219 s->equiv[0] = s->str[0]; 220 if (s->str[1] != '=') 221 err("misplaced equivalence equals sign"); 222 } 223 s->str += 2; 224 s->cnt = 0; 225 s->state = SET; 226 s->set = s->equiv; 227 } 228 229 static int 230 genrange(s) 231 STR *s; 232 { 233 int stopval; 234 char *savestart; 235 236 savestart = s->str; 237 stopval = *++s->str == '\\' ? backslash(s) : *s->str++; 238 if (stopval < s->lastch) { 239 s->str = savestart; 240 return (0); 241 } 242 s->cnt = stopval - s->lastch + 1; 243 s->state = RANGE; 244 --s->lastch; 245 return (1); 246 } 247 248 static void 249 genseq(s) 250 STR *s; 251 { 252 char *ep; 253 254 if (s->which == STRING1) 255 err("sequences only valid in string2"); 256 257 if (*s->str == '\\') 258 s->lastch = backslash(s); 259 else 260 s->lastch = *s->str++; 261 if (*s->str != '*') 262 err("misplaced sequence asterisk"); 263 264 switch (*++s->str) { 265 case '\\': 266 s->cnt = backslash(s); 267 break; 268 case ']': 269 s->cnt = 0; 270 ++s->str; 271 break; 272 default: 273 if (isdigit(*s->str)) { 274 s->cnt = strtol(s->str, &ep, 0); 275 if (*ep == ']') { 276 s->str = ep + 1; 277 break; 278 } 279 } 280 err("illegal sequence count"); 281 /* NOTREACHED */ 282 } 283 284 s->state = s->cnt ? SEQUENCE : INFINITE; 285 } 286 287 /* 288 * Translate \??? into a character. Up to 3 octal digits, if no digits either 289 * an escape code or a literal character. 290 */ 291 static int 292 backslash(s) 293 register STR *s; 294 { 295 register int ch, cnt, val; 296 297 for (cnt = val = 0;;) { 298 ch = *++s->str; 299 if (!isascii(ch) || !isdigit(ch)) 300 break; 301 val = val * 8 + ch - '0'; 302 if (++cnt == 3) { 303 ++s->str; 304 break; 305 } 306 } 307 if (cnt) 308 return (val); 309 if (ch != '\0') 310 ++s->str; 311 switch (ch) { 312 case 'a': /* escape characters */ 313 return ('\7'); 314 case 'b': 315 return ('\b'); 316 case 'f': 317 return ('\f'); 318 case 'n': 319 return ('\n'); 320 case 'r': 321 return ('\r'); 322 case 't': 323 return ('\t'); 324 case 'v': 325 return ('\13'); 326 case '\0': /* \" -> \ */ 327 s->state = EOS; 328 return ('\\'); 329 default: /* \x" -> x */ 330 return (ch); 331 } 332 } 333
Indexes created Mon Sep 22 13:09:51 GMT 2025