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. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)str.c 8.2 (Berkeley) 4/28/95 30 * $FreeBSD: src/usr.bin/tr/str.c,v 1.10.2.2 2002/07/29 12:59:33 tjr Exp $ 31 */ 32 33 #include <sys/types.h> 34 35 #include <ctype.h> 36 #include <err.h> 37 #include <stddef.h> 38 #include <stdio.h> 39 #include <stdlib.h> 40 #include <string.h> 41 42 #include "extern.h" 43 44 static int backslash(STR *); 45 static int bracket(STR *); 46 static int c_class(const void *, const void *); 47 static void genclass(STR *); 48 static void genequiv(STR *); 49 static int genrange(STR *); 50 static void genseq(STR *); 51 52 int 53 next(STR *s) 54 { 55 int ch; 56 57 switch (s->state) { 58 case EOS: 59 return (0); 60 case INFINITE: 61 return (1); 62 case NORMAL: 63 switch (ch = (u_char)*s->str) { 64 case '\0': 65 s->state = EOS; 66 return (0); 67 case '\\': 68 s->lastch = backslash(s); 69 break; 70 case '[': 71 if (bracket(s)) 72 return (next(s)); 73 /* FALLTHROUGH */ 74 default: 75 ++s->str; 76 s->lastch = ch; 77 break; 78 } 79 80 /* We can start a range at any time. */ 81 if (s->str[0] == '-' && genrange(s)) 82 return (next(s)); 83 return (1); 84 case RANGE: 85 if (s->cnt-- == 0) { 86 s->state = NORMAL; 87 return (next(s)); 88 } 89 ++s->lastch; 90 return (1); 91 case SEQUENCE: 92 if (s->cnt-- == 0) { 93 s->state = NORMAL; 94 return (next(s)); 95 } 96 return (1); 97 case SET: 98 if ((s->lastch = s->set[s->cnt++]) == OOBCH) { 99 s->state = NORMAL; 100 return (next(s)); 101 } 102 return (1); 103 default: 104 return (0); 105 } 106 /* NOTREACHED */ 107 } 108 109 static int 110 bracket(STR *s) 111 { 112 char *p; 113 114 switch (s->str[1]) { 115 case ':': /* "[:class:]" */ 116 if ((p = strchr(s->str + 2, ']')) == NULL) 117 return (0); 118 if (*(p - 1) != ':' || p - s->str < 4) 119 goto repeat; 120 *(p - 1) = '\0'; 121 s->str += 2; 122 genclass(s); 123 s->str = p + 1; 124 return (1); 125 case '=': /* "[=equiv=]" */ 126 if ((p = strchr(s->str + 2, ']')) == NULL) 127 return (0); 128 if (*(p - 1) != '=' || p - s->str < 4) 129 goto repeat; 130 s->str += 2; 131 genequiv(s); 132 return (1); 133 default: /* "[\###*n]" or "[#*n]" */ 134 repeat: 135 if ((p = strpbrk(s->str + 2, "*]")) == NULL) 136 return (0); 137 if (p[0] != '*' || strchr(p, ']') == NULL) 138 return (0); 139 s->str += 1; 140 genseq(s); 141 return (1); 142 } 143 /* NOTREACHED */ 144 } 145 146 typedef struct { 147 const char *name; 148 int (*func)(int); 149 int *set; 150 } CLASS; 151 152 static CLASS classes[] = { 153 #undef isalnum 154 { "alnum", isalnum, NULL }, 155 #undef isalpha 156 { "alpha", isalpha, NULL }, 157 #undef isblank 158 { "blank", isblank, NULL }, 159 #undef iscntrl 160 { "cntrl", iscntrl, NULL }, 161 #undef isdigit 162 { "digit", isdigit, NULL }, 163 #undef isgraph 164 { "graph", isgraph, NULL }, 165 #undef islower 166 { "lower", islower, NULL }, 167 #undef isprint 168 { "print", isprint, NULL }, 169 #undef ispunct 170 { "punct", ispunct, NULL }, 171 #undef isspace 172 { "space", isspace, NULL }, 173 #undef isupper 174 { "upper", isupper, NULL }, 175 #undef isxdigit 176 { "xdigit", isxdigit, NULL }, 177 }; 178 179 static void 180 genclass(STR *s) 181 { 182 int cnt, (*func)(int); 183 CLASS *cp, tmp; 184 int *p; 185 186 tmp.name = s->str; 187 if ((cp = (CLASS *)bsearch(&tmp, classes, sizeof(classes) / 188 sizeof(CLASS), sizeof(CLASS), c_class)) == NULL) 189 errx(1, "unknown class %s", s->str); 190 191 if ((cp->set = p = malloc((NCHARS + 1) * sizeof(int))) == NULL) 192 err(1, "malloc"); 193 bzero(p, (NCHARS + 1) * sizeof(int)); 194 for (cnt = 0, func = cp->func; cnt < NCHARS; ++cnt) 195 if ((func)(cnt)) 196 *p++ = cnt; 197 *p = OOBCH; 198 199 s->cnt = 0; 200 s->state = SET; 201 s->set = cp->set; 202 } 203 204 static int 205 c_class(const void *a, const void *b) 206 { 207 return (strcmp(((const CLASS *)a)->name, ((const CLASS *)b)->name)); 208 } 209 210 static void 211 genequiv(STR *s) 212 { 213 int i, p, pri; 214 char src[2], dst[3]; 215 216 if (*s->str == '\\') { 217 s->equiv[0] = backslash(s); 218 if (*s->str != '=') 219 errx(1, "misplaced equivalence equals sign"); 220 s->str += 2; 221 } else { 222 s->equiv[0] = s->str[0]; 223 if (s->str[1] != '=') 224 errx(1, "misplaced equivalence equals sign"); 225 s->str += 3; 226 } 227 228 /* 229 * Calculate the set of all characters in the same equivalence class 230 * as the specified character (they will have the same primary 231 * collation weights). 232 * XXX Knows too much about how strxfrm() is implemented. Assumes 233 * it fills the string with primary collation weight bytes. Only one- 234 * to-one mappings are supported. 235 */ 236 src[0] = s->equiv[0]; 237 src[1] = '\0'; 238 if (strxfrm(dst, src, sizeof(dst)) == 1) { 239 pri = (unsigned char)*dst; 240 for (p = 1, i = 1; i < NCHARS; i++) { 241 *src = i; 242 if (strxfrm(dst, src, sizeof(dst)) == 1 && pri && 243 pri == (unsigned char)*dst) 244 s->equiv[p++] = i; 245 } 246 s->equiv[p] = OOBCH; 247 } 248 249 s->cnt = 0; 250 s->state = SET; 251 s->set = s->equiv; 252 } 253 254 static int 255 genrange(STR *s) 256 { 257 int stopval; 258 char *savestart; 259 260 savestart = s->str; 261 stopval = *++s->str == '\\' ? backslash(s) : (u_char)*s->str++; 262 if (stopval < (u_char)s->lastch) { 263 s->str = savestart; 264 return (0); 265 } 266 s->cnt = stopval - s->lastch + 1; 267 s->state = RANGE; 268 --s->lastch; 269 return (1); 270 } 271 272 static void 273 genseq(STR *s) 274 { 275 char *ep; 276 277 if (s->which == STRING1) 278 errx(1, "sequences only valid in string2"); 279 280 if (*s->str == '\\') 281 s->lastch = backslash(s); 282 else 283 s->lastch = *s->str++; 284 if (*s->str != '*') 285 errx(1, "misplaced sequence asterisk"); 286 287 switch (*++s->str) { 288 case '\\': 289 s->cnt = backslash(s); 290 break; 291 case ']': 292 s->cnt = 0; 293 ++s->str; 294 break; 295 default: 296 if (isdigit((u_char)*s->str)) { 297 s->cnt = strtol(s->str, &ep, 0); 298 if (*ep == ']') { 299 s->str = ep + 1; 300 break; 301 } 302 } 303 errx(1, "illegal sequence count"); 304 /* NOTREACHED */ 305 } 306 307 s->state = s->cnt ? SEQUENCE : INFINITE; 308 } 309 310 /* 311 * Translate \??? into a character. Up to 3 octal digits, if no digits either 312 * an escape code or a literal character. 313 */ 314 static int 315 backslash(STR *s) 316 { 317 int ch, cnt, val; 318 319 for (cnt = val = 0;;) { 320 ch = (u_char)*++s->str; 321 if (!isascii(ch) || !isdigit(ch)) 322 break; 323 val = val * 8 + ch - '0'; 324 if (++cnt == 3) { 325 ++s->str; 326 break; 327 } 328 } 329 if (cnt) 330 return (val); 331 if (ch != '\0') 332 ++s->str; 333 switch (ch) { 334 case 'a': /* escape characters */ 335 return ('\7'); 336 case 'b': 337 return ('\b'); 338 case 'f': 339 return ('\f'); 340 case 'n': 341 return ('\n'); 342 case 'r': 343 return ('\r'); 344 case 't': 345 return ('\t'); 346 case 'v': 347 return ('\13'); 348 case '\0': /* \" -> \ */ 349 s->state = EOS; 350 return ('\\'); 351 default: /* \x" -> x */ 352 return (ch); 353 } 354 } 355