| 1 | #include <sys/types.h> |
| 2 | #include <stdio.h> |
| 3 | #include <string.h> |
| 4 | #include <ctype.h> |
| 5 | #include <limits.h> |
| 6 | #include <stdlib.h> |
| 7 | #include "regex.h" |
| 8 | |
| 9 | #include "utils.h" |
| 10 | #include "regex2.h" |
| 11 | |
| 12 | #include "cclass.h" |
| 13 | #include "cname.h" |
| 14 | |
| 15 | /* |
| 16 | * parse structure, passed up and down to avoid global variables and |
| 17 | * other clumsinesses |
| 18 | */ |
| 19 | struct parse { |
| 20 | char *next; /* next character in RE */ |
| 21 | char *end; /* end of string (-> NUL normally) */ |
| 22 | int error; /* has an error been seen? */ |
| 23 | sop *strip; /* malloced strip */ |
| 24 | sopno ssize; /* malloced strip size (allocated) */ |
| 25 | sopno slen; /* malloced strip length (used) */ |
| 26 | int ncsalloc; /* number of csets allocated */ |
| 27 | struct re_guts *g; |
| 28 | # define NPAREN 10 /* we need to remember () 1-9 for back refs */ |
| 29 | sopno pbegin[NPAREN]; /* -> ( ([0] unused) */ |
| 30 | sopno pend[NPAREN]; /* -> ) ([0] unused) */ |
| 31 | }; |
| 32 | |
| 33 | #include "regcomp.ih" |
| 34 | |
| 35 | static char nuls[10]; /* place to point scanner in event of error */ |
| 36 | |
| 37 | /* |
| 38 | * macros for use with parse structure |
| 39 | * BEWARE: these know that the parse structure is named `p' !!! |
| 40 | */ |
| 41 | #define PEEK() (*p->next) |
| 42 | #define PEEK2() (*(p->next+1)) |
| 43 | #define MORE() (p->next < p->end) |
| 44 | #define MORE2() (p->next+1 < p->end) |
| 45 | #define SEE(c) (MORE() && PEEK() == (c)) |
| 46 | #define SEETWO(a, b) (MORE() && MORE2() && PEEK() == (a) && PEEK2() == (b)) |
| 47 | #define EAT(c) ((SEE(c)) ? (NEXT(), 1) : 0) |
| 48 | #define EATTWO(a, b) ((SEETWO(a, b)) ? (NEXT2(), 1) : 0) |
| 49 | #define NEXT() (p->next++) |
| 50 | #define NEXT2() (p->next += 2) |
| 51 | #define NEXTn(n) (p->next += (n)) |
| 52 | #define GETNEXT() (*p->next++) |
| 53 | #define SETERROR(e) seterr(p, (e)) |
| 54 | #define REQUIRE(co, e) ((void)((co) || SETERROR(e))) |
| 55 | #define MUSTSEE(c, e) (REQUIRE(MORE() && PEEK() == (c), e)) |
| 56 | #define MUSTEAT(c, e) (REQUIRE(MORE() && GETNEXT() == (c), e)) |
| 57 | #define MUSTNOTSEE(c, e) (REQUIRE(!MORE() || PEEK() != (c), e)) |
| 58 | #define EMIT(op, sopnd) doemit(p, (sop)(op), (size_t)(sopnd)) |
| 59 | #define INSERT(op, pos) doinsert(p, (sop)(op), HERE()-(pos)+1, pos) |
| 60 | #define AHEAD(pos) dofwd(p, pos, HERE()-(pos)) |
| 61 | #define ASTERN(sop, pos) EMIT(sop, HERE()-pos) |
| 62 | #define HERE() (p->slen) |
| 63 | #define THERE() (p->slen - 1) |
| 64 | #define THERETHERE() (p->slen - 2) |
| 65 | #define DROP(n) (p->slen -= (n)) |
| 66 | |
| 67 | #ifndef NDEBUG |
| 68 | static int never = 0; /* for use in asserts; shuts lint up */ |
| 69 | #else |
| 70 | #define never 0 /* some <assert.h>s have bugs too */ |
| 71 | #endif |
| 72 | |
| 73 | /* |
| 74 | - regcomp - interface for parser and compilation |
| 75 | = extern int regcomp(regex_t *, const char *, int); |
| 76 | = #define REG_BASIC 0000 |
| 77 | = #define REG_EXTENDED 0001 |
| 78 | = #define REG_ICASE 0002 |
| 79 | = #define REG_NOSUB 0004 |
| 80 | = #define REG_NEWLINE 0010 |
| 81 | = #define REG_NOSPEC 0020 |
| 82 | = #define REG_PEND 0040 |
| 83 | = #define REG_DUMP 0200 |
| 84 | */ |
| 85 | int /* 0 success, otherwise REG_something */ |
| 86 | regcomp(preg, pattern, cflags) |
| 87 | regex_t *preg; |
| 88 | const char *pattern; |
| 89 | int cflags; |
| 90 | { |
| 91 | struct parse pa; |
| 92 | register struct re_guts *g; |
| 93 | register struct parse *p = &pa; |
| 94 | register int i; |
| 95 | register size_t len; |
| 96 | #ifdef REDEBUG |
| 97 | # define GOODFLAGS(f) (f) |
| 98 | #else |
| 99 | # define GOODFLAGS(f) ((f)&~REG_DUMP) |
| 100 | #endif |
| 101 | |
| 102 | cflags = GOODFLAGS(cflags); |
| 103 | if ((cflags®_EXTENDED) && (cflags®_NOSPEC)) |
| 104 | return(REG_INVARG); |
| 105 | |
| 106 | if (cflags®_PEND) { |
| 107 | if (preg->re_endp < pattern) |
| 108 | return(REG_INVARG); |
| 109 | len = preg->re_endp - pattern; |
| 110 | } else |
| 111 | len = strlen((char *)pattern); |
| 112 | |
| 113 | /* do the mallocs early so failure handling is easy */ |
| 114 | g = (struct re_guts *)malloc(sizeof(struct re_guts) + |
| 115 | (NC-1)*sizeof(cat_t)); |
| 116 | if (g == NULL) |
| 117 | return(REG_ESPACE); |
| 118 | p->ssize = len/(size_t)2*(size_t)3 + (size_t)1; /* ugh */ |
| 119 | p->strip = (sop *)malloc(p->ssize * sizeof(sop)); |
| 120 | p->slen = 0; |
| 121 | if (p->strip == NULL) { |
| 122 | free((char *)g); |
| 123 | return(REG_ESPACE); |
| 124 | } |
| 125 | |
| 126 | /* set things up */ |
| 127 | p->g = g; |
| 128 | p->next = (char *)pattern; /* convenience; we do not modify it */ |
| 129 | p->end = p->next + len; |
| 130 | p->error = 0; |
| 131 | p->ncsalloc = 0; |
| 132 | for (i = 0; i < NPAREN; i++) { |
| 133 | p->pbegin[i] = 0; |
| 134 | p->pend[i] = 0; |
| 135 | } |
| 136 | g->csetsize = NC; |
| 137 | g->sets = NULL; |
| 138 | g->setbits = NULL; |
| 139 | g->ncsets = 0; |
| 140 | g->cflags = cflags; |
| 141 | g->iflags = 0; |
| 142 | g->nbol = 0; |
| 143 | g->neol = 0; |
| 144 | g->must = NULL; |
| 145 | g->mlen = 0; |
| 146 | g->nsub = 0; |
| 147 | g->ncategories = 1; /* category 0 is "everything else" */ |
| 148 | g->categories = &g->catspace[-(CHAR_MIN)]; |
| 149 | (void) memset((char *)g->catspace, 0, NC*sizeof(cat_t)); |
| 150 | g->backrefs = 0; |
| 151 | |
| 152 | /* do it */ |
| 153 | EMIT(OEND, 0); |
| 154 | g->firststate = THERE(); |
| 155 | if (cflags®_EXTENDED) |
| 156 | p_ere(p, OUT); |
| 157 | else if (cflags®_NOSPEC) |
| 158 | p_str(p); |
| 159 | else |
| 160 | p_bre(p, OUT, OUT); |
| 161 | EMIT(OEND, 0); |
| 162 | g->laststate = THERE(); |
| 163 | |
| 164 | /* tidy up loose ends and fill things in */ |
| 165 | categorize(p, g); |
| 166 | stripsnug(p, g); |
| 167 | findmust(p, g); |
| 168 | g->nplus = pluscount(p, g); |
| 169 | g->magic = MAGIC2; |
| 170 | preg->re_nsub = g->nsub; |
| 171 | preg->re_g = g; |
| 172 | preg->re_magic = MAGIC1; |
| 173 | #ifndef REDEBUG |
| 174 | /* not debugging, so can't rely on the assert() in regexec() */ |
| 175 | if (g->iflags&BAD) |
| 176 | SETERROR(REG_ASSERT); |
| 177 | #endif |
| 178 | |
| 179 | /* win or lose, we're done */ |
| 180 | if (p->error != 0) /* lose */ |
| 181 | regfree(preg); |
| 182 | return(p->error); |
| 183 | } |
| 184 | |
| 185 | /* |
| 186 | - p_ere - ERE parser top level, concatenation and alternation |
| 187 | == static void p_ere(register struct parse *p, int stop); |
| 188 | */ |
| 189 | static void |
| 190 | p_ere(p, stop) |
| 191 | register struct parse *p; |
| 192 | int stop; /* character this ERE should end at */ |
| 193 | { |
| 194 | register char c; |
| 195 | register sopno prevback; |
| 196 | register sopno prevfwd; |
| 197 | register sopno conc; |
| 198 | register int first = 1; /* is this the first alternative? */ |
| 199 | |
| 200 | for (;;) { |
| 201 | /* do a bunch of concatenated expressions */ |
| 202 | conc = HERE(); |
| 203 | while (MORE() && (c = PEEK()) != '|' && c != stop) |
| 204 | p_ere_exp(p); |
| 205 | REQUIRE(HERE() != conc, REG_EMPTY); /* require nonempty */ |
| 206 | |
| 207 | if (!EAT('|')) |
| 208 | break; /* NOTE BREAK OUT */ |
| 209 | |
| 210 | if (first) { |
| 211 | INSERT(OCH_, conc); /* offset is wrong */ |
| 212 | prevfwd = conc; |
| 213 | prevback = conc; |
| 214 | first = 0; |
| 215 | } |
| 216 | ASTERN(OOR1, prevback); |
| 217 | prevback = THERE(); |
| 218 | AHEAD(prevfwd); /* fix previous offset */ |
| 219 | prevfwd = HERE(); |
| 220 | EMIT(OOR2, 0); /* offset is very wrong */ |
| 221 | } |
| 222 | |
| 223 | if (!first) { /* tail-end fixups */ |
| 224 | AHEAD(prevfwd); |
| 225 | ASTERN(O_CH, prevback); |
| 226 | } |
| 227 | |
| 228 | assert(!MORE() || SEE(stop)); |
| 229 | } |
| 230 | |
| 231 | /* |
| 232 | - p_ere_exp - parse one subERE, an atom possibly followed by a repetition op |
| 233 | == static void p_ere_exp(register struct parse *p); |
| 234 | */ |
| 235 | static void |
| 236 | p_ere_exp(p) |
| 237 | register struct parse *p; |
| 238 | { |
| 239 | register char c; |
| 240 | register sopno pos; |
| 241 | register int count; |
| 242 | register int count2; |
| 243 | register sopno subno; |
| 244 | int wascaret = 0; |
| 245 | |
| 246 | assert(MORE()); /* caller should have ensured this */ |
| 247 | c = GETNEXT(); |
| 248 | |
| 249 | pos = HERE(); |
| 250 | switch (c) { |
| 251 | case '(': |
| 252 | REQUIRE(MORE(), REG_EPAREN); |
| 253 | p->g->nsub++; |
| 254 | subno = p->g->nsub; |
| 255 | if (subno < NPAREN) |
| 256 | p->pbegin[subno] = HERE(); |
| 257 | EMIT(OLPAREN, subno); |
| 258 | if (!SEE(')')) |
| 259 | p_ere(p, ')'); |
| 260 | if (subno < NPAREN) { |
| 261 | p->pend[subno] = HERE(); |
| 262 | assert(p->pend[subno] != 0); |
| 263 | } |
| 264 | EMIT(ORPAREN, subno); |
| 265 | MUSTEAT(')', REG_EPAREN); |
| 266 | break; |
| 267 | #ifndef POSIX_MISTAKE |
| 268 | case ')': /* happens only if no current unmatched ( */ |
| 269 | /* |
| 270 | * You may ask, why the ifndef? Because I didn't notice |
| 271 | * this until slightly too late for 1003.2, and none of the |
| 272 | * other 1003.2 regular-expression reviewers noticed it at |
| 273 | * all. So an unmatched ) is legal POSIX, at least until |
| 274 | * we can get it fixed. |
| 275 | */ |
| 276 | SETERROR(REG_EPAREN); |
| 277 | break; |
| 278 | #endif |
| 279 | case '^': |
| 280 | EMIT(OBOL, 0); |
| 281 | p->g->iflags |= USEBOL; |
| 282 | p->g->nbol++; |
| 283 | wascaret = 1; |
| 284 | break; |
| 285 | case '$': |
| 286 | EMIT(OEOL, 0); |
| 287 | p->g->iflags |= USEEOL; |
| 288 | p->g->neol++; |
| 289 | break; |
| 290 | case '|': |
| 291 | SETERROR(REG_EMPTY); |
| 292 | break; |
| 293 | case '*': |
| 294 | case '+': |
| 295 | case '?': |
| 296 | SETERROR(REG_BADRPT); |
| 297 | break; |
| 298 | case '.': |
| 299 | if (p->g->cflags®_NEWLINE) |
| 300 | nonnewline(p); |
| 301 | else |
| 302 | EMIT(OANY, 0); |
| 303 | break; |
| 304 | case '[': |
| 305 | p_bracket(p); |
| 306 | break; |
| 307 | case '\\': |
| 308 | REQUIRE(MORE(), REG_EESCAPE); |
| 309 | c = GETNEXT(); |
| 310 | ordinary(p, c); |
| 311 | break; |
| 312 | case '{': /* okay as ordinary except if digit follows */ |
| 313 | REQUIRE(!MORE() || !isdigit(PEEK()), REG_BADRPT); |
| 314 | /* FALLTHROUGH */ |
| 315 | default: |
| 316 | ordinary(p, c); |
| 317 | break; |
| 318 | } |
| 319 | |
| 320 | if (!MORE()) |
| 321 | return; |
| 322 | c = PEEK(); |
| 323 | /* we call { a repetition if followed by a digit */ |
| 324 | if (!( c == '*' || c == '+' || c == '?' || |
| 325 | (c == '{' && MORE2() && isdigit(PEEK2())) )) |
| 326 | return; /* no repetition, we're done */ |
| 327 | NEXT(); |
| 328 | |
| 329 | REQUIRE(!wascaret, REG_BADRPT); |
| 330 | switch (c) { |
| 331 | case '*': /* implemented as +? */ |
| 332 | /* this case does not require the (y|) trick, noKLUDGE */ |
| 333 | INSERT(OPLUS_, pos); |
| 334 | ASTERN(O_PLUS, pos); |
| 335 | INSERT(OQUEST_, pos); |
| 336 | ASTERN(O_QUEST, pos); |
| 337 | break; |
| 338 | case '+': |
| 339 | INSERT(OPLUS_, pos); |
| 340 | ASTERN(O_PLUS, pos); |
| 341 | break; |
| 342 | case '?': |
| 343 | /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ |
| 344 | INSERT(OCH_, pos); /* offset slightly wrong */ |
| 345 | ASTERN(OOR1, pos); /* this one's right */ |
| 346 | AHEAD(pos); /* fix the OCH_ */ |
| 347 | EMIT(OOR2, 0); /* offset very wrong... */ |
| 348 | AHEAD(THERE()); /* ...so fix it */ |
| 349 | ASTERN(O_CH, THERETHERE()); |
| 350 | break; |
| 351 | case '{': |
| 352 | count = p_count(p); |
| 353 | if (EAT(',')) { |
| 354 | if (isdigit(PEEK())) { |
| 355 | count2 = p_count(p); |
| 356 | REQUIRE(count <= count2, REG_BADBR); |
| 357 | } else /* single number with comma */ |
| 358 | count2 = INFINITY; |
| 359 | } else /* just a single number */ |
| 360 | count2 = count; |
| 361 | repeat(p, pos, count, count2); |
| 362 | if (!EAT('}')) { /* error heuristics */ |
| 363 | while (MORE() && PEEK() != '}') |
| 364 | NEXT(); |
| 365 | REQUIRE(MORE(), REG_EBRACE); |
| 366 | SETERROR(REG_BADBR); |
| 367 | } |
| 368 | break; |
| 369 | } |
| 370 | |
| 371 | if (!MORE()) |
| 372 | return; |
| 373 | c = PEEK(); |
| 374 | if (!( c == '*' || c == '+' || c == '?' || |
| 375 | (c == '{' && MORE2() && isdigit(PEEK2())) ) ) |
| 376 | return; |
| 377 | SETERROR(REG_BADRPT); |
| 378 | } |
| 379 | |
| 380 | /* |
| 381 | - p_str - string (no metacharacters) "parser" |
| 382 | == static void p_str(register struct parse *p); |
| 383 | */ |
| 384 | static void |
| 385 | p_str(p) |
| 386 | register struct parse *p; |
| 387 | { |
| 388 | REQUIRE(MORE(), REG_EMPTY); |
| 389 | while (MORE()) |
| 390 | ordinary(p, GETNEXT()); |
| 391 | } |
| 392 | |
| 393 | /* |
| 394 | - p_bre - BRE parser top level, anchoring and concatenation |
| 395 | == static void p_bre(register struct parse *p, register int end1, \ |
| 396 | == register int end2); |
| 397 | * Giving end1 as OUT essentially eliminates the end1/end2 check. |
| 398 | * |
| 399 | * This implementation is a bit of a kludge, in that a trailing $ is first |
| 400 | * taken as an ordinary character and then revised to be an anchor. The |
| 401 | * only undesirable side effect is that '$' gets included as a character |
| 402 | * category in such cases. This is fairly harmless; not worth fixing. |
| 403 | * The amount of lookahead needed to avoid this kludge is excessive. |
| 404 | */ |
| 405 | static void |
| 406 | p_bre(p, end1, end2) |
| 407 | register struct parse *p; |
| 408 | register int end1; /* first terminating character */ |
| 409 | register int end2; /* second terminating character */ |
| 410 | { |
| 411 | register sopno start = HERE(); |
| 412 | register int first = 1; /* first subexpression? */ |
| 413 | register int wasdollar = 0; |
| 414 | |
| 415 | if (EAT('^')) { |
| 416 | EMIT(OBOL, 0); |
| 417 | p->g->iflags |= USEBOL; |
| 418 | p->g->nbol++; |
| 419 | } |
| 420 | while (MORE() && !SEETWO(end1, end2)) { |
| 421 | wasdollar = p_simp_re(p, first); |
| 422 | first = 0; |
| 423 | } |
| 424 | if (wasdollar) { /* oops, that was a trailing anchor */ |
| 425 | DROP(1); |
| 426 | EMIT(OEOL, 0); |
| 427 | p->g->iflags |= USEEOL; |
| 428 | p->g->neol++; |
| 429 | } |
| 430 | |
| 431 | REQUIRE(HERE() != start, REG_EMPTY); /* require nonempty */ |
| 432 | } |
| 433 | |
| 434 | /* |
| 435 | - p_simp_re - parse a simple RE, an atom possibly followed by a repetition |
| 436 | == static int p_simp_re(register struct parse *p, int starordinary); |
| 437 | */ |
| 438 | static int /* was the simple RE an unbackslashed $? */ |
| 439 | p_simp_re(p, starordinary) |
| 440 | register struct parse *p; |
| 441 | int starordinary; /* is a leading * an ordinary character? */ |
| 442 | { |
| 443 | register int c; |
| 444 | register int count; |
| 445 | register int count2; |
| 446 | register sopno pos; |
| 447 | register int i; |
| 448 | register sopno subno; |
| 449 | # define BACKSL (1<<CHAR_BIT) |
| 450 | |
| 451 | pos = HERE(); /* repetion op, if any, covers from here */ |
| 452 | |
| 453 | assert(MORE()); /* caller should have ensured this */ |
| 454 | c = GETNEXT(); |
| 455 | if (c == '\\') { |
| 456 | REQUIRE(MORE(), REG_EESCAPE); |
| 457 | c = BACKSL | (unsigned char)GETNEXT(); |
| 458 | } |
| 459 | switch (c) { |
| 460 | case '.': |
| 461 | if (p->g->cflags®_NEWLINE) |
| 462 | nonnewline(p); |
| 463 | else |
| 464 | EMIT(OANY, 0); |
| 465 | break; |
| 466 | case '[': |
| 467 | p_bracket(p); |
| 468 | break; |
| 469 | case BACKSL|'{': |
| 470 | SETERROR(REG_BADRPT); |
| 471 | break; |
| 472 | case BACKSL|'(': |
| 473 | p->g->nsub++; |
| 474 | subno = p->g->nsub; |
| 475 | if (subno < NPAREN) |
| 476 | p->pbegin[subno] = HERE(); |
| 477 | EMIT(OLPAREN, subno); |
| 478 | /* the MORE here is an error heuristic */ |
| 479 | if (MORE() && !SEETWO('\\', ')')) |
| 480 | p_bre(p, '\\', ')'); |
| 481 | if (subno < NPAREN) { |
| 482 | p->pend[subno] = HERE(); |
| 483 | assert(p->pend[subno] != 0); |
| 484 | } |
| 485 | EMIT(ORPAREN, subno); |
| 486 | REQUIRE(EATTWO('\\', ')'), REG_EPAREN); |
| 487 | break; |
| 488 | case BACKSL|')': /* should not get here -- must be user */ |
| 489 | case BACKSL|'}': |
| 490 | SETERROR(REG_EPAREN); |
| 491 | break; |
| 492 | case BACKSL|'1': |
| 493 | case BACKSL|'2': |
| 494 | case BACKSL|'3': |
| 495 | case BACKSL|'4': |
| 496 | case BACKSL|'5': |
| 497 | case BACKSL|'6': |
| 498 | case BACKSL|'7': |
| 499 | case BACKSL|'8': |
| 500 | case BACKSL|'9': |
| 501 | i = (c&~BACKSL) - '0'; |
| 502 | assert(i < NPAREN); |
| 503 | if (p->pend[i] != 0) { |
| 504 | assert(i <= p->g->nsub); |
| 505 | EMIT(OBACK_, i); |
| 506 | assert(p->pbegin[i] != 0); |
| 507 | assert(OP(p->strip[p->pbegin[i]]) == OLPAREN); |
| 508 | assert(OP(p->strip[p->pend[i]]) == ORPAREN); |
| 509 | (void) dupl(p, p->pbegin[i]+1, p->pend[i]); |
| 510 | EMIT(O_BACK, i); |
| 511 | } else |
| 512 | SETERROR(REG_ESUBREG); |
| 513 | p->g->backrefs = 1; |
| 514 | break; |
| 515 | case '*': |
| 516 | REQUIRE(starordinary, REG_BADRPT); |
| 517 | /* FALLTHROUGH */ |
| 518 | default: |
| 519 | ordinary(p, (char)c); /* takes off BACKSL, if any */ |
| 520 | break; |
| 521 | } |
| 522 | |
| 523 | if (EAT('*')) { /* implemented as +? */ |
| 524 | /* this case does not require the (y|) trick, noKLUDGE */ |
| 525 | INSERT(OPLUS_, pos); |
| 526 | ASTERN(O_PLUS, pos); |
| 527 | INSERT(OQUEST_, pos); |
| 528 | ASTERN(O_QUEST, pos); |
| 529 | } else if (EATTWO('\\', '{')) { |
| 530 | count = p_count(p); |
| 531 | if (EAT(',')) { |
| 532 | if (MORE() && isdigit(PEEK())) { |
| 533 | count2 = p_count(p); |
| 534 | REQUIRE(count <= count2, REG_BADBR); |
| 535 | } else /* single number with comma */ |
| 536 | count2 = INFINITY; |
| 537 | } else /* just a single number */ |
| 538 | count2 = count; |
| 539 | repeat(p, pos, count, count2); |
| 540 | if (!EATTWO('\\', '}')) { /* error heuristics */ |
| 541 | while (MORE() && !SEETWO('\\', '}')) |
| 542 | NEXT(); |
| 543 | REQUIRE(MORE(), REG_EBRACE); |
| 544 | SETERROR(REG_BADBR); |
| 545 | } |
| 546 | } else if (c == (unsigned char)'$') /* $ (but not \$) ends it */ |
| 547 | return(1); |
| 548 | |
| 549 | return(0); |
| 550 | } |
| 551 | |
| 552 | /* |
| 553 | - p_count - parse a repetition count |
| 554 | == static int p_count(register struct parse *p); |
| 555 | */ |
| 556 | static int /* the value */ |
| 557 | p_count(p) |
| 558 | register struct parse *p; |
| 559 | { |
| 560 | register int count = 0; |
| 561 | register int ndigits = 0; |
| 562 | |
| 563 | while (MORE() && isdigit(PEEK()) && count <= DUPMAX) { |
| 564 | count = count*10 + (GETNEXT() - '0'); |
| 565 | ndigits++; |
| 566 | } |
| 567 | |
| 568 | REQUIRE(ndigits > 0 && count <= DUPMAX, REG_BADBR); |
| 569 | return(count); |
| 570 | } |
| 571 | |
| 572 | /* |
| 573 | - p_bracket - parse a bracketed character list |
| 574 | == static void p_bracket(register struct parse *p); |
| 575 | * |
| 576 | * Note a significant property of this code: if the allocset() did SETERROR, |
| 577 | * no set operations are done. |
| 578 | */ |
| 579 | static void |
| 580 | p_bracket(p) |
| 581 | register struct parse *p; |
| 582 | { |
| 583 | register cset *cs = allocset(p); |
| 584 | register int invert = 0; |
| 585 | |
| 586 | /* Dept of Truly Sickening Special-Case Kludges */ |
| 587 | if (p->next + 5 < p->end && strncmp(p->next, "[:<:]]", 6) == 0) { |
| 588 | EMIT(OBOW, 0); |
| 589 | NEXTn(6); |
| 590 | return; |
| 591 | } |
| 592 | if (p->next + 5 < p->end && strncmp(p->next, "[:>:]]", 6) == 0) { |
| 593 | EMIT(OEOW, 0); |
| 594 | NEXTn(6); |
| 595 | return; |
| 596 | } |
| 597 | |
| 598 | if (EAT('^')) |
| 599 | invert++; /* make note to invert set at end */ |
| 600 | if (EAT(']')) |
| 601 | CHadd(cs, ']'); |
| 602 | else if (EAT('-')) |
| 603 | CHadd(cs, '-'); |
| 604 | while (MORE() && PEEK() != ']' && !SEETWO('-', ']')) |
| 605 | p_b_term(p, cs); |
| 606 | if (EAT('-')) |
| 607 | CHadd(cs, '-'); |
| 608 | MUSTEAT(']', REG_EBRACK); |
| 609 | |
| 610 | if (p->error != 0) /* don't mess things up further */ |
| 611 | return; |
| 612 | |
| 613 | if (p->g->cflags®_ICASE) { |
| 614 | register int i; |
| 615 | register int ci; |
| 616 | |
| 617 | for (i = p->g->csetsize - 1; i >= 0; i--) |
| 618 | if (CHIN(cs, i) && isalpha(i)) { |
| 619 | ci = othercase(i); |
| 620 | if (ci != i) |
| 621 | CHadd(cs, ci); |
| 622 | } |
| 623 | if (cs->multis != NULL) |
| 624 | mccase(p, cs); |
| 625 | } |
| 626 | if (invert) { |
| 627 | register int i; |
| 628 | |
| 629 | for (i = p->g->csetsize - 1; i >= 0; i--) |
| 630 | if (CHIN(cs, i)) |
| 631 | CHsub(cs, i); |
| 632 | else |
| 633 | CHadd(cs, i); |
| 634 | if (p->g->cflags®_NEWLINE) |
| 635 | CHsub(cs, '\n'); |
| 636 | if (cs->multis != NULL) |
| 637 | mcinvert(p, cs); |
| 638 | } |
| 639 | |
| 640 | assert(cs->multis == NULL); /* xxx */ |
| 641 | |
| 642 | if (nch(p, cs) == 1) { /* optimize singleton sets */ |
| 643 | ordinary(p, firstch(p, cs)); |
| 644 | freeset(p, cs); |
| 645 | } else |
| 646 | EMIT(OANYOF, freezeset(p, cs)); |
| 647 | } |
| 648 | |
| 649 | /* |
| 650 | - p_b_term - parse one term of a bracketed character list |
| 651 | == static void p_b_term(register struct parse *p, register cset *cs); |
| 652 | */ |
| 653 | static void |
| 654 | p_b_term(p, cs) |
| 655 | register struct parse *p; |
| 656 | register cset *cs; |
| 657 | { |
| 658 | register char c; |
| 659 | register char start, finish; |
| 660 | register int i; |
| 661 | |
| 662 | /* classify what we've got */ |
| 663 | switch ((MORE()) ? PEEK() : '\0') { |
| 664 | case '[': |
| 665 | c = (MORE2()) ? PEEK2() : '\0'; |
| 666 | break; |
| 667 | case '-': |
| 668 | SETERROR(REG_ERANGE); |
| 669 | return; /* NOTE RETURN */ |
| 670 | break; |
| 671 | default: |
| 672 | c = '\0'; |
| 673 | break; |
| 674 | } |
| 675 | |
| 676 | switch (c) { |
| 677 | case ':': /* character class */ |
| 678 | NEXT2(); |
| 679 | REQUIRE(MORE(), REG_EBRACK); |
| 680 | c = PEEK(); |
| 681 | REQUIRE(c != '-' && c != ']', REG_ECTYPE); |
| 682 | p_b_cclass(p, cs); |
| 683 | REQUIRE(MORE(), REG_EBRACK); |
| 684 | REQUIRE(EATTWO(':', ']'), REG_ECTYPE); |
| 685 | break; |
| 686 | case '=': /* equivalence class */ |
| 687 | NEXT2(); |
| 688 | REQUIRE(MORE(), REG_EBRACK); |
| 689 | c = PEEK(); |
| 690 | REQUIRE(c != '-' && c != ']', REG_ECOLLATE); |
| 691 | p_b_eclass(p, cs); |
| 692 | REQUIRE(MORE(), REG_EBRACK); |
| 693 | REQUIRE(EATTWO('=', ']'), REG_ECOLLATE); |
| 694 | break; |
| 695 | default: /* symbol, ordinary character, or range */ |
| 696 | /* xxx revision needed for multichar stuff */ |
| 697 | start = p_b_symbol(p); |
| 698 | if (SEE('-') && MORE2() && PEEK2() != ']') { |
| 699 | /* range */ |
| 700 | NEXT(); |
| 701 | if (EAT('-')) |
| 702 | finish = '-'; |
| 703 | else |
| 704 | finish = p_b_symbol(p); |
| 705 | } else |
| 706 | finish = start; |
| 707 | /* xxx what about signed chars here... */ |
| 708 | REQUIRE(start <= finish, REG_ERANGE); |
| 709 | for (i = start; i <= finish; i++) |
| 710 | CHadd(cs, i); |
| 711 | break; |
| 712 | } |
| 713 | } |
| 714 | |
| 715 | /* |
| 716 | - p_b_cclass - parse a character-class name and deal with it |
| 717 | == static void p_b_cclass(register struct parse *p, register cset *cs); |
| 718 | */ |
| 719 | static void |
| 720 | p_b_cclass(p, cs) |
| 721 | register struct parse *p; |
| 722 | register cset *cs; |
| 723 | { |
| 724 | register char *sp = p->next; |
| 725 | register struct cclass *cp; |
| 726 | register size_t len; |
| 727 | register char *u; |
| 728 | register char c; |
| 729 | |
| 730 | while (MORE() && isalpha(PEEK())) |
| 731 | NEXT(); |
| 732 | len = p->next - sp; |
| 733 | for (cp = cclasses; cp->name != NULL; cp++) |
| 734 | if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0') |
| 735 | break; |
| 736 | if (cp->name == NULL) { |
| 737 | /* oops, didn't find it */ |
| 738 | SETERROR(REG_ECTYPE); |
| 739 | return; |
| 740 | } |
| 741 | |
| 742 | u = cp->chars; |
| 743 | while ((c = *u++) != '\0') |
| 744 | CHadd(cs, c); |
| 745 | for (u = cp->multis; *u != '\0'; u += strlen(u) + 1) |
| 746 | MCadd(p, cs, u); |
| 747 | } |
| 748 | |
| 749 | /* |
| 750 | - p_b_eclass - parse an equivalence-class name and deal with it |
| 751 | == static void p_b_eclass(register struct parse *p, register cset *cs); |
| 752 | * |
| 753 | * This implementation is incomplete. xxx |
| 754 | */ |
| 755 | static void |
| 756 | p_b_eclass(p, cs) |
| 757 | register struct parse *p; |
| 758 | register cset *cs; |
| 759 | { |
| 760 | register char c; |
| 761 | |
| 762 | c = p_b_coll_elem(p, '='); |
| 763 | CHadd(cs, c); |
| 764 | } |
| 765 | |
| 766 | /* |
| 767 | - p_b_symbol - parse a character or [..]ed multicharacter collating symbol |
| 768 | == static char p_b_symbol(register struct parse *p); |
| 769 | */ |
| 770 | static char /* value of symbol */ |
| 771 | p_b_symbol(p) |
| 772 | register struct parse *p; |
| 773 | { |
| 774 | register char value; |
| 775 | |
| 776 | REQUIRE(MORE(), REG_EBRACK); |
| 777 | if (!EATTWO('[', '.')) |
| 778 | return(GETNEXT()); |
| 779 | |
| 780 | /* collating symbol */ |
| 781 | value = p_b_coll_elem(p, '.'); |
| 782 | REQUIRE(EATTWO('.', ']'), REG_ECOLLATE); |
| 783 | return(value); |
| 784 | } |
| 785 | |
| 786 | /* |
| 787 | - p_b_coll_elem - parse a collating-element name and look it up |
| 788 | == static char p_b_coll_elem(register struct parse *p, int endc); |
| 789 | */ |
| 790 | static char /* value of collating element */ |
| 791 | p_b_coll_elem(p, endc) |
| 792 | register struct parse *p; |
| 793 | int endc; /* name ended by endc,']' */ |
| 794 | { |
| 795 | register char *sp = p->next; |
| 796 | register struct cname *cp; |
| 797 | register int len; |
| 798 | |
| 799 | while (MORE() && !SEETWO(endc, ']')) |
| 800 | NEXT(); |
| 801 | if (!MORE()) { |
| 802 | SETERROR(REG_EBRACK); |
| 803 | return(0); |
| 804 | } |
| 805 | len = p->next - sp; |
| 806 | for (cp = cnames; cp->name != NULL; cp++) |
| 807 | if (strncmp(cp->name, sp, len) == 0 && cp->name[len] == '\0') |
| 808 | return(cp->code); /* known name */ |
| 809 | if (len == 1) |
| 810 | return(*sp); /* single character */ |
| 811 | SETERROR(REG_ECOLLATE); /* neither */ |
| 812 | return(0); |
| 813 | } |
| 814 | |
| 815 | /* |
| 816 | - othercase - return the case counterpart of an alphabetic |
| 817 | == static char othercase(int ch); |
| 818 | */ |
| 819 | static char /* if no counterpart, return ch */ |
| 820 | othercase(ch) |
| 821 | int ch; |
| 822 | { |
| 823 | assert(isalpha(ch)); |
| 824 | if (isupper(ch)) |
| 825 | return(tolower(ch)); |
| 826 | else if (islower(ch)) |
| 827 | return(toupper(ch)); |
| 828 | else /* peculiar, but could happen */ |
| 829 | return(ch); |
| 830 | } |
| 831 | |
| 832 | /* |
| 833 | - bothcases - emit a dualcase version of a two-case character |
| 834 | == static void bothcases(register struct parse *p, int ch); |
| 835 | * |
| 836 | * Boy, is this implementation ever a kludge... |
| 837 | */ |
| 838 | static void |
| 839 | bothcases(p, ch) |
| 840 | register struct parse *p; |
| 841 | int ch; |
| 842 | { |
| 843 | register char *oldnext = p->next; |
| 844 | register char *oldend = p->end; |
| 845 | char bracket[3]; |
| 846 | |
| 847 | assert(othercase(ch) != ch); /* p_bracket() would recurse */ |
| 848 | p->next = bracket; |
| 849 | p->end = bracket+2; |
| 850 | bracket[0] = ch; |
| 851 | bracket[1] = ']'; |
| 852 | bracket[2] = '\0'; |
| 853 | p_bracket(p); |
| 854 | assert(p->next == bracket+2); |
| 855 | p->next = oldnext; |
| 856 | p->end = oldend; |
| 857 | } |
| 858 | |
| 859 | /* |
| 860 | - ordinary - emit an ordinary character |
| 861 | == static void ordinary(register struct parse *p, register int ch); |
| 862 | */ |
| 863 | static void |
| 864 | ordinary(p, ch) |
| 865 | register struct parse *p; |
| 866 | register int ch; |
| 867 | { |
| 868 | register cat_t *cap = p->g->categories; |
| 869 | |
| 870 | if ((p->g->cflags®_ICASE) && isalpha(ch) && othercase(ch) != ch) |
| 871 | bothcases(p, ch); |
| 872 | else { |
| 873 | EMIT(OCHAR, (unsigned char)ch); |
| 874 | if (cap[ch] == 0) |
| 875 | cap[ch] = p->g->ncategories++; |
| 876 | } |
| 877 | } |
| 878 | |
| 879 | /* |
| 880 | - nonnewline - emit REG_NEWLINE version of OANY |
| 881 | == static void nonnewline(register struct parse *p); |
| 882 | * |
| 883 | * Boy, is this implementation ever a kludge... |
| 884 | */ |
| 885 | static void |
| 886 | nonnewline(p) |
| 887 | register struct parse *p; |
| 888 | { |
| 889 | register char *oldnext = p->next; |
| 890 | register char *oldend = p->end; |
| 891 | char bracket[4]; |
| 892 | |
| 893 | p->next = bracket; |
| 894 | p->end = bracket+3; |
| 895 | bracket[0] = '^'; |
| 896 | bracket[1] = '\n'; |
| 897 | bracket[2] = ']'; |
| 898 | bracket[3] = '\0'; |
| 899 | p_bracket(p); |
| 900 | assert(p->next == bracket+3); |
| 901 | p->next = oldnext; |
| 902 | p->end = oldend; |
| 903 | } |
| 904 | |
| 905 | /* |
| 906 | - repeat - generate code for a bounded repetition, recursively if needed |
| 907 | == static void repeat(register struct parse *p, sopno start, int from, int to); |
| 908 | */ |
| 909 | static void |
| 910 | repeat(p, start, from, to) |
| 911 | register struct parse *p; |
| 912 | sopno start; /* operand from here to end of strip */ |
| 913 | int from; /* repeated from this number */ |
| 914 | int to; /* to this number of times (maybe INFINITY) */ |
| 915 | { |
| 916 | register sopno finish = HERE(); |
| 917 | # define N 2 |
| 918 | # define INF 3 |
| 919 | # define REP(f, t) ((f)*8 + (t)) |
| 920 | # define MAP(n) (((n) <= 1) ? (n) : ((n) == INFINITY) ? INF : N) |
| 921 | register sopno copy; |
| 922 | |
| 923 | if (p->error != 0) /* head off possible runaway recursion */ |
| 924 | return; |
| 925 | |
| 926 | assert(from <= to); |
| 927 | |
| 928 | switch (REP(MAP(from), MAP(to))) { |
| 929 | case REP(0, 0): /* must be user doing this */ |
| 930 | DROP(finish-start); /* drop the operand */ |
| 931 | break; |
| 932 | case REP(0, 1): /* as x{1,1}? */ |
| 933 | case REP(0, N): /* as x{1,n}? */ |
| 934 | case REP(0, INF): /* as x{1,}? */ |
| 935 | /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ |
| 936 | INSERT(OCH_, start); /* offset is wrong... */ |
| 937 | repeat(p, start+1, 1, to); |
| 938 | ASTERN(OOR1, start); |
| 939 | AHEAD(start); /* ... fix it */ |
| 940 | EMIT(OOR2, 0); |
| 941 | AHEAD(THERE()); |
| 942 | ASTERN(O_CH, THERETHERE()); |
| 943 | break; |
| 944 | case REP(1, 1): /* trivial case */ |
| 945 | /* done */ |
| 946 | break; |
| 947 | case REP(1, N): /* as x?x{1,n-1} */ |
| 948 | /* KLUDGE: emit y? as (y|) until subtle bug gets fixed */ |
| 949 | INSERT(OCH_, start); |
| 950 | ASTERN(OOR1, start); |
| 951 | AHEAD(start); |
| 952 | EMIT(OOR2, 0); /* offset very wrong... */ |
| 953 | AHEAD(THERE()); /* ...so fix it */ |
| 954 | ASTERN(O_CH, THERETHERE()); |
| 955 | copy = dupl(p, start+1, finish+1); |
| 956 | assert(copy == finish+4); |
| 957 | repeat(p, copy, 1, to-1); |
| 958 | break; |
| 959 | case REP(1, INF): /* as x+ */ |
| 960 | INSERT(OPLUS_, start); |
| 961 | ASTERN(O_PLUS, start); |
| 962 | break; |
| 963 | case REP(N, N): /* as xx{m-1,n-1} */ |
| 964 | copy = dupl(p, start, finish); |
| 965 | repeat(p, copy, from-1, to-1); |
| 966 | break; |
| 967 | case REP(N, INF): /* as xx{n-1,INF} */ |
| 968 | copy = dupl(p, start, finish); |
| 969 | repeat(p, copy, from-1, to); |
| 970 | break; |
| 971 | default: /* "can't happen" */ |
| 972 | SETERROR(REG_ASSERT); /* just in case */ |
| 973 | break; |
| 974 | } |
| 975 | } |
| 976 | |
| 977 | /* |
| 978 | - seterr - set an error condition |
| 979 | == static int seterr(register struct parse *p, int e); |
| 980 | */ |
| 981 | static int /* useless but makes type checking happy */ |
| 982 | seterr(p, e) |
| 983 | register struct parse *p; |
| 984 | int e; |
| 985 | { |
| 986 | if (p->error == 0) /* keep earliest error condition */ |
| 987 | p->error = e; |
| 988 | p->next = nuls; /* try to bring things to a halt */ |
| 989 | p->end = nuls; |
| 990 | return(0); /* make the return value well-defined */ |
| 991 | } |
| 992 | |
| 993 | /* |
| 994 | - allocset - allocate a set of characters for [] |
| 995 | == static cset *allocset(register struct parse *p); |
| 996 | */ |
| 997 | static cset * |
| 998 | allocset(p) |
| 999 | register struct parse *p; |
| 1000 | { |
| 1001 | register int no = p->g->ncsets++; |
| 1002 | register size_t nc; |
| 1003 | register size_t nbytes; |
| 1004 | register cset *cs; |
| 1005 | register size_t css = (size_t)p->g->csetsize; |
| 1006 | register int i; |
| 1007 | |
| 1008 | if (no >= p->ncsalloc) { /* need another column of space */ |
| 1009 | p->ncsalloc += CHAR_BIT; |
| 1010 | nc = p->ncsalloc; |
| 1011 | assert(nc % CHAR_BIT == 0); |
| 1012 | nbytes = nc / CHAR_BIT * css; |
| 1013 | if (p->g->sets == NULL) |
| 1014 | p->g->sets = (cset *)malloc(nc * sizeof(cset)); |
| 1015 | else |
| 1016 | p->g->sets = (cset *)realloc((char *)p->g->sets, |
| 1017 | nc * sizeof(cset)); |
| 1018 | if (p->g->setbits == NULL) |
| 1019 | p->g->setbits = (uch *)malloc(nbytes); |
| 1020 | else { |
| 1021 | p->g->setbits = (uch *)realloc((char *)p->g->setbits, |
| 1022 | nbytes); |
| 1023 | /* xxx this isn't right if setbits is now NULL */ |
| 1024 | for (i = 0; i < no; i++) |
| 1025 | p->g->sets[i].ptr = p->g->setbits + css*(i/CHAR_BIT); |
| 1026 | } |
| 1027 | if (p->g->sets != NULL && p->g->setbits != NULL) |
| 1028 | (void) memset((char *)p->g->setbits + (nbytes - css), |
| 1029 | 0, css); |
| 1030 | else { |
| 1031 | no = 0; |
| 1032 | SETERROR(REG_ESPACE); |
| 1033 | /* caller's responsibility not to do set ops */ |
| 1034 | } |
| 1035 | } |
| 1036 | |
| 1037 | assert(p->g->sets != NULL); /* xxx */ |
| 1038 | cs = &p->g->sets[no]; |
| 1039 | cs->ptr = p->g->setbits + css*((no)/CHAR_BIT); |
| 1040 | cs->mask = 1 << ((no) % CHAR_BIT); |
| 1041 | cs->hash = 0; |
| 1042 | cs->smultis = 0; |
| 1043 | cs->multis = NULL; |
| 1044 | |
| 1045 | return(cs); |
| 1046 | } |
| 1047 | |
| 1048 | /* |
| 1049 | - freeset - free a now-unused set |
| 1050 | == static void freeset(register struct parse *p, register cset *cs); |
| 1051 | */ |
| 1052 | static void |
| 1053 | freeset(p, cs) |
| 1054 | register struct parse *p; |
| 1055 | register cset *cs; |
| 1056 | { |
| 1057 | register size_t i; |
| 1058 | register cset *top = &p->g->sets[p->g->ncsets]; |
| 1059 | register size_t css = (size_t)p->g->csetsize; |
| 1060 | |
| 1061 | for (i = 0; i < css; i++) |
| 1062 | CHsub(cs, i); |
| 1063 | if (cs == top-1) /* recover only the easy case */ |
| 1064 | p->g->ncsets--; |
| 1065 | } |
| 1066 | |
| 1067 | /* |
| 1068 | - freezeset - final processing on a set of characters |
| 1069 | == static int freezeset(register struct parse *p, register cset *cs); |
| 1070 | * |
| 1071 | * The main task here is merging identical sets. This is usually a waste |
| 1072 | * of time (although the hash code minimizes the overhead), but can win |
| 1073 | * big if REG_ICASE is being used. REG_ICASE, by the way, is why the hash |
| 1074 | * is done using addition rather than xor -- all ASCII [aA] sets xor to |
| 1075 | * the same value! |
| 1076 | */ |
| 1077 | static int /* set number */ |
| 1078 | freezeset(p, cs) |
| 1079 | register struct parse *p; |
| 1080 | register cset *cs; |
| 1081 | { |
| 1082 | register uch h = cs->hash; |
| 1083 | register size_t i; |
| 1084 | register cset *top = &p->g->sets[p->g->ncsets]; |
| 1085 | register cset *cs2; |
| 1086 | register size_t css = (size_t)p->g->csetsize; |
| 1087 | |
| 1088 | /* look for an earlier one which is the same */ |
| 1089 | for (cs2 = &p->g->sets[0]; cs2 < top; cs2++) |
| 1090 | if (cs2->hash == h && cs2 != cs) { |
| 1091 | /* maybe */ |
| 1092 | for (i = 0; i < css; i++) |
| 1093 | if (!!CHIN(cs2, i) != !!CHIN(cs, i)) |
| 1094 | break; /* no */ |
| 1095 | if (i == css) |
| 1096 | break; /* yes */ |
| 1097 | } |
| 1098 | |
| 1099 | if (cs2 < top) { /* found one */ |
| 1100 | freeset(p, cs); |
| 1101 | cs = cs2; |
| 1102 | } |
| 1103 | |
| 1104 | return((int)(cs - p->g->sets)); |
| 1105 | } |
| 1106 | |
| 1107 | /* |
| 1108 | - firstch - return first character in a set (which must have at least one) |
| 1109 | == static int firstch(register struct parse *p, register cset *cs); |
| 1110 | */ |
| 1111 | static int /* character; there is no "none" value */ |
| 1112 | firstch(p, cs) |
| 1113 | register struct parse *p; |
| 1114 | register cset *cs; |
| 1115 | { |
| 1116 | register size_t i; |
| 1117 | register size_t css = (size_t)p->g->csetsize; |
| 1118 | |
| 1119 | for (i = 0; i < css; i++) |
| 1120 | if (CHIN(cs, i)) |
| 1121 | return((char)i); |
| 1122 | assert(never); |
| 1123 | return(0); /* arbitrary */ |
| 1124 | } |
| 1125 | |
| 1126 | /* |
| 1127 | - nch - number of characters in a set |
| 1128 | == static int nch(register struct parse *p, register cset *cs); |
| 1129 | */ |
| 1130 | static int |
| 1131 | nch(p, cs) |
| 1132 | register struct parse *p; |
| 1133 | register cset *cs; |
| 1134 | { |
| 1135 | register size_t i; |
| 1136 | register size_t css = (size_t)p->g->csetsize; |
| 1137 | register int n = 0; |
| 1138 | |
| 1139 | for (i = 0; i < css; i++) |
| 1140 | if (CHIN(cs, i)) |
| 1141 | n++; |
| 1142 | return(n); |
| 1143 | } |
| 1144 | |
| 1145 | /* |
| 1146 | - mcadd - add a collating element to a cset |
| 1147 | == static void mcadd(register struct parse *p, register cset *cs, \ |
| 1148 | == register char *cp); |
| 1149 | */ |
| 1150 | static void |
| 1151 | mcadd(p, cs, cp) |
| 1152 | register struct parse *p; |
| 1153 | register cset *cs; |
| 1154 | register char *cp; |
| 1155 | { |
| 1156 | register size_t oldend = cs->smultis; |
| 1157 | |
| 1158 | cs->smultis += strlen(cp) + 1; |
| 1159 | if (cs->multis == NULL) |
| 1160 | cs->multis = malloc(cs->smultis); |
| 1161 | else |
| 1162 | cs->multis = realloc(cs->multis, cs->smultis); |
| 1163 | if (cs->multis == NULL) { |
| 1164 | SETERROR(REG_ESPACE); |
| 1165 | return; |
| 1166 | } |
| 1167 | |
| 1168 | (void) strcpy(cs->multis + oldend - 1, cp); |
| 1169 | cs->multis[cs->smultis - 1] = '\0'; |
| 1170 | } |
| 1171 | |
| 1172 | /* these functions don't seem to be used (yet?), suppress warnings */ |
| 1173 | #if 0 |
| 1174 | /* |
| 1175 | - mcsub - subtract a collating element from a cset |
| 1176 | == static void mcsub(register cset *cs, register char *cp); |
| 1177 | */ |
| 1178 | static void |
| 1179 | mcsub(cs, cp) |
| 1180 | register cset *cs; |
| 1181 | register char *cp; |
| 1182 | { |
| 1183 | register char *fp = mcfind(cs, cp); |
| 1184 | register size_t len = strlen(fp); |
| 1185 | |
| 1186 | assert(fp != NULL); |
| 1187 | (void) memmove(fp, fp + len + 1, |
| 1188 | cs->smultis - (fp + len + 1 - cs->multis)); |
| 1189 | cs->smultis -= len; |
| 1190 | |
| 1191 | if (cs->smultis == 0) { |
| 1192 | free(cs->multis); |
| 1193 | cs->multis = NULL; |
| 1194 | return; |
| 1195 | } |
| 1196 | |
| 1197 | cs->multis = realloc(cs->multis, cs->smultis); |
| 1198 | assert(cs->multis != NULL); |
| 1199 | } |
| 1200 | |
| 1201 | /* |
| 1202 | - mcin - is a collating element in a cset? |
| 1203 | == static int mcin(register cset *cs, register char *cp); |
| 1204 | */ |
| 1205 | static int |
| 1206 | mcin(cs, cp) |
| 1207 | register cset *cs; |
| 1208 | register char *cp; |
| 1209 | { |
| 1210 | return(mcfind(cs, cp) != NULL); |
| 1211 | } |
| 1212 | |
| 1213 | /* |
| 1214 | - mcfind - find a collating element in a cset |
| 1215 | == static char *mcfind(register cset *cs, register char *cp); |
| 1216 | */ |
| 1217 | static char * |
| 1218 | mcfind(cs, cp) |
| 1219 | register cset *cs; |
| 1220 | register char *cp; |
| 1221 | { |
| 1222 | register char *p; |
| 1223 | |
| 1224 | if (cs->multis == NULL) |
| 1225 | return(NULL); |
| 1226 | for (p = cs->multis; *p != '\0'; p += strlen(p) + 1) |
| 1227 | if (strcmp(cp, p) == 0) |
| 1228 | return(p); |
| 1229 | return(NULL); |
| 1230 | } |
| 1231 | #endif /* 0 */ |
| 1232 | |
| 1233 | /* |
| 1234 | - mcinvert - invert the list of collating elements in a cset |
| 1235 | == static void mcinvert(register struct parse *p, register cset *cs); |
| 1236 | * |
| 1237 | * This would have to know the set of possibilities. Implementation |
| 1238 | * is deferred. |
| 1239 | */ |
| 1240 | static void |
| 1241 | mcinvert(p, cs) |
| 1242 | register struct parse *p; |
| 1243 | register cset *cs; |
| 1244 | { |
| 1245 | assert(cs->multis == NULL); /* xxx */ |
| 1246 | } |
| 1247 | |
| 1248 | /* |
| 1249 | - mccase - add case counterparts of the list of collating elements in a cset |
| 1250 | == static void mccase(register struct parse *p, register cset *cs); |
| 1251 | * |
| 1252 | * This would have to know the set of possibilities. Implementation |
| 1253 | * is deferred. |
| 1254 | */ |
| 1255 | static void |
| 1256 | mccase(p, cs) |
| 1257 | register struct parse *p; |
| 1258 | register cset *cs; |
| 1259 | { |
| 1260 | assert(cs->multis == NULL); /* xxx */ |
| 1261 | } |
| 1262 | |
| 1263 | /* |
| 1264 | - isinsets - is this character in any sets? |
| 1265 | == static int isinsets(register struct re_guts *g, int c); |
| 1266 | */ |
| 1267 | static int /* predicate */ |
| 1268 | isinsets(g, c) |
| 1269 | register struct re_guts *g; |
| 1270 | int c; |
| 1271 | { |
| 1272 | register uch *col; |
| 1273 | register int i; |
| 1274 | register int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT; |
| 1275 | register unsigned uc = (unsigned char)c; |
| 1276 | |
| 1277 | for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) |
| 1278 | if (col[uc] != 0) |
| 1279 | return(1); |
| 1280 | return(0); |
| 1281 | } |
| 1282 | |
| 1283 | /* |
| 1284 | - samesets - are these two characters in exactly the same sets? |
| 1285 | == static int samesets(register struct re_guts *g, int c1, int c2); |
| 1286 | */ |
| 1287 | static int /* predicate */ |
| 1288 | samesets(g, c1, c2) |
| 1289 | register struct re_guts *g; |
| 1290 | int c1; |
| 1291 | int c2; |
| 1292 | { |
| 1293 | register uch *col; |
| 1294 | register int i; |
| 1295 | register int ncols = (g->ncsets+(CHAR_BIT-1)) / CHAR_BIT; |
| 1296 | register unsigned uc1 = (unsigned char)c1; |
| 1297 | register unsigned uc2 = (unsigned char)c2; |
| 1298 | |
| 1299 | for (i = 0, col = g->setbits; i < ncols; i++, col += g->csetsize) |
| 1300 | if (col[uc1] != col[uc2]) |
| 1301 | return(0); |
| 1302 | return(1); |
| 1303 | } |
| 1304 | |
| 1305 | /* |
| 1306 | - categorize - sort out character categories |
| 1307 | == static void categorize(struct parse *p, register struct re_guts *g); |
| 1308 | */ |
| 1309 | static void |
| 1310 | categorize(p, g) |
| 1311 | struct parse *p; |
| 1312 | register struct re_guts *g; |
| 1313 | { |
| 1314 | register cat_t *cats = g->categories; |
| 1315 | register int c; |
| 1316 | register int c2; |
| 1317 | register cat_t cat; |
| 1318 | |
| 1319 | /* avoid making error situations worse */ |
| 1320 | if (p->error != 0) |
| 1321 | return; |
| 1322 | |
| 1323 | for (c = CHAR_MIN; c <= CHAR_MAX; c++) |
| 1324 | if (cats[c] == 0 && isinsets(g, c)) { |
| 1325 | cat = g->ncategories++; |
| 1326 | cats[c] = cat; |
| 1327 | for (c2 = c+1; c2 <= CHAR_MAX; c2++) |
| 1328 | if (cats[c2] == 0 && samesets(g, c, c2)) |
| 1329 | cats[c2] = cat; |
| 1330 | } |
| 1331 | } |
| 1332 | |
| 1333 | /* |
| 1334 | - dupl - emit a duplicate of a bunch of sops |
| 1335 | == static sopno dupl(register struct parse *p, sopno start, sopno finish); |
| 1336 | */ |
| 1337 | static sopno /* start of duplicate */ |
| 1338 | dupl(p, start, finish) |
| 1339 | register struct parse *p; |
| 1340 | sopno start; /* from here */ |
| 1341 | sopno finish; /* to this less one */ |
| 1342 | { |
| 1343 | register sopno ret = HERE(); |
| 1344 | register sopno len = finish - start; |
| 1345 | |
| 1346 | assert(finish >= start); |
| 1347 | if (len == 0) |
| 1348 | return(ret); |
| 1349 | enlarge(p, p->ssize + len); /* this many unexpected additions */ |
| 1350 | assert(p->ssize >= p->slen + len); |
| 1351 | (void) memcpy((char *)(p->strip + p->slen), |
| 1352 | (char *)(p->strip + start), (size_t)len*sizeof(sop)); |
| 1353 | p->slen += len; |
| 1354 | return(ret); |
| 1355 | } |
| 1356 | |
| 1357 | /* |
| 1358 | - doemit - emit a strip operator |
| 1359 | == static void doemit(register struct parse *p, sop op, size_t opnd); |
| 1360 | * |
| 1361 | * It might seem better to implement this as a macro with a function as |
| 1362 | * hard-case backup, but it's just too big and messy unless there are |
| 1363 | * some changes to the data structures. Maybe later. |
| 1364 | */ |
| 1365 | static void |
| 1366 | doemit(p, op, opnd) |
| 1367 | register struct parse *p; |
| 1368 | sop op; |
| 1369 | size_t opnd; |
| 1370 | { |
| 1371 | /* avoid making error situations worse */ |
| 1372 | if (p->error != 0) |
| 1373 | return; |
| 1374 | |
| 1375 | /* deal with oversize operands ("can't happen", more or less) */ |
| 1376 | assert(opnd < 1<<OPSHIFT); |
| 1377 | |
| 1378 | /* deal with undersized strip */ |
| 1379 | if (p->slen >= p->ssize) |
| 1380 | enlarge(p, (p->ssize+1) / 2 * 3); /* +50% */ |
| 1381 | assert(p->slen < p->ssize); |
| 1382 | |
| 1383 | /* finally, it's all reduced to the easy case */ |
| 1384 | p->strip[p->slen++] = SOP(op, opnd); |
| 1385 | } |
| 1386 | |
| 1387 | /* |
| 1388 | - doinsert - insert a sop into the strip |
| 1389 | == static void doinsert(register struct parse *p, sop op, size_t opnd, sopno pos); |
| 1390 | */ |
| 1391 | static void |
| 1392 | doinsert(p, op, opnd, pos) |
| 1393 | register struct parse *p; |
| 1394 | sop op; |
| 1395 | size_t opnd; |
| 1396 | sopno pos; |
| 1397 | { |
| 1398 | register sopno sn; |
| 1399 | register sop s; |
| 1400 | register int i; |
| 1401 | |
| 1402 | /* avoid making error situations worse */ |
| 1403 | if (p->error != 0) |
| 1404 | return; |
| 1405 | |
| 1406 | sn = HERE(); |
| 1407 | EMIT(op, opnd); /* do checks, ensure space */ |
| 1408 | assert(HERE() == sn+1); |
| 1409 | s = p->strip[sn]; |
| 1410 | |
| 1411 | /* adjust paren pointers */ |
| 1412 | assert(pos > 0); |
| 1413 | for (i = 1; i < NPAREN; i++) { |
| 1414 | if (p->pbegin[i] >= pos) { |
| 1415 | p->pbegin[i]++; |
| 1416 | } |
| 1417 | if (p->pend[i] >= pos) { |
| 1418 | p->pend[i]++; |
| 1419 | } |
| 1420 | } |
| 1421 | |
| 1422 | memmove((char *)&p->strip[pos+1], (char *)&p->strip[pos], |
| 1423 | (HERE()-pos-1)*sizeof(sop)); |
| 1424 | p->strip[pos] = s; |
| 1425 | } |
| 1426 | |
| 1427 | /* |
| 1428 | - dofwd - complete a forward reference |
| 1429 | == static void dofwd(register struct parse *p, sopno pos, sop value); |
| 1430 | */ |
| 1431 | static void |
| 1432 | dofwd(p, pos, value) |
| 1433 | register struct parse *p; |
| 1434 | register sopno pos; |
| 1435 | sop value; |
| 1436 | { |
| 1437 | /* avoid making error situations worse */ |
| 1438 | if (p->error != 0) |
| 1439 | return; |
| 1440 | |
| 1441 | assert(value < 1<<OPSHIFT); |
| 1442 | p->strip[pos] = OP(p->strip[pos]) | value; |
| 1443 | } |
| 1444 | |
| 1445 | /* |
| 1446 | - enlarge - enlarge the strip |
| 1447 | == static void enlarge(register struct parse *p, sopno size); |
| 1448 | */ |
| 1449 | static void |
| 1450 | enlarge(p, size) |
| 1451 | register struct parse *p; |
| 1452 | register sopno size; |
| 1453 | { |
| 1454 | register sop *sp; |
| 1455 | |
| 1456 | if (p->ssize >= size) |
| 1457 | return; |
| 1458 | |
| 1459 | sp = (sop *)realloc(p->strip, size*sizeof(sop)); |
| 1460 | if (sp == NULL) { |
| 1461 | SETERROR(REG_ESPACE); |
| 1462 | return; |
| 1463 | } |
| 1464 | p->strip = sp; |
| 1465 | p->ssize = size; |
| 1466 | } |
| 1467 | |
| 1468 | /* |
| 1469 | - stripsnug - compact the strip |
| 1470 | == static void stripsnug(register struct parse *p, register struct re_guts *g); |
| 1471 | */ |
| 1472 | static void |
| 1473 | stripsnug(p, g) |
| 1474 | register struct parse *p; |
| 1475 | register struct re_guts *g; |
| 1476 | { |
| 1477 | g->nstates = p->slen; |
| 1478 | g->strip = (sop *)realloc((char *)p->strip, p->slen * sizeof(sop)); |
| 1479 | if (g->strip == NULL) { |
| 1480 | SETERROR(REG_ESPACE); |
| 1481 | g->strip = p->strip; |
| 1482 | } |
| 1483 | } |
| 1484 | |
| 1485 | /* |
| 1486 | - findmust - fill in must and mlen with longest mandatory literal string |
| 1487 | == static void findmust(register struct parse *p, register struct re_guts *g); |
| 1488 | * |
| 1489 | * This algorithm could do fancy things like analyzing the operands of | |
| 1490 | * for common subsequences. Someday. This code is simple and finds most |
| 1491 | * of the interesting cases. |
| 1492 | * |
| 1493 | * Note that must and mlen got initialized during setup. |
| 1494 | */ |
| 1495 | static void |
| 1496 | findmust(p, g) |
| 1497 | struct parse *p; |
| 1498 | register struct re_guts *g; |
| 1499 | { |
| 1500 | register sop *scan; |
| 1501 | sop *start; |
| 1502 | register sop *newstart; |
| 1503 | register sopno newlen; |
| 1504 | register sop s; |
| 1505 | register char *cp; |
| 1506 | register sopno i; |
| 1507 | |
| 1508 | /* avoid making error situations worse */ |
| 1509 | if (p->error != 0) |
| 1510 | return; |
| 1511 | |
| 1512 | /* find the longest OCHAR sequence in strip */ |
| 1513 | newlen = 0; |
| 1514 | scan = g->strip + 1; |
| 1515 | do { |
| 1516 | s = *scan++; |
| 1517 | switch (OP(s)) { |
| 1518 | case OCHAR: /* sequence member */ |
| 1519 | if (newlen == 0) /* new sequence */ |
| 1520 | newstart = scan - 1; |
| 1521 | newlen++; |
| 1522 | break; |
| 1523 | case OPLUS_: /* things that don't break one */ |
| 1524 | case OLPAREN: |
| 1525 | case ORPAREN: |
| 1526 | break; |
| 1527 | case OQUEST_: /* things that must be skipped */ |
| 1528 | case OCH_: |
| 1529 | scan--; |
| 1530 | do { |
| 1531 | scan += OPND(s); |
| 1532 | s = *scan; |
| 1533 | /* assert() interferes w debug printouts */ |
| 1534 | if (OP(s) != O_QUEST && OP(s) != O_CH && |
| 1535 | OP(s) != OOR2) { |
| 1536 | g->iflags |= BAD; |
| 1537 | return; |
| 1538 | } |
| 1539 | } while (OP(s) != O_QUEST && OP(s) != O_CH); |
| 1540 | /* fallthrough */ |
| 1541 | default: /* things that break a sequence */ |
| 1542 | if (newlen > g->mlen) { /* ends one */ |
| 1543 | start = newstart; |
| 1544 | g->mlen = newlen; |
| 1545 | } |
| 1546 | newlen = 0; |
| 1547 | break; |
| 1548 | } |
| 1549 | } while (OP(s) != OEND); |
| 1550 | |
| 1551 | if (g->mlen == 0) /* there isn't one */ |
| 1552 | return; |
| 1553 | |
| 1554 | /* turn it into a character string */ |
| 1555 | g->must = malloc((size_t)g->mlen + 1); |
| 1556 | if (g->must == NULL) { /* argh; just forget it */ |
| 1557 | g->mlen = 0; |
| 1558 | return; |
| 1559 | } |
| 1560 | cp = g->must; |
| 1561 | scan = start; |
| 1562 | for (i = g->mlen; i > 0; i--) { |
| 1563 | while (OP(s = *scan++) != OCHAR) |
| 1564 | continue; |
| 1565 | assert(cp < g->must + g->mlen); |
| 1566 | *cp++ = (char)OPND(s); |
| 1567 | } |
| 1568 | assert(cp == g->must + g->mlen); |
| 1569 | *cp++ = '\0'; /* just on general principles */ |
| 1570 | } |
| 1571 | |
| 1572 | /* |
| 1573 | - pluscount - count + nesting |
| 1574 | == static sopno pluscount(register struct parse *p, register struct re_guts *g); |
| 1575 | */ |
| 1576 | static sopno /* nesting depth */ |
| 1577 | pluscount(p, g) |
| 1578 | struct parse *p; |
| 1579 | register struct re_guts *g; |
| 1580 | { |
| 1581 | register sop *scan; |
| 1582 | register sop s; |
| 1583 | register sopno plusnest = 0; |
| 1584 | register sopno maxnest = 0; |
| 1585 | |
| 1586 | if (p->error != 0) |
| 1587 | return(0); /* there may not be an OEND */ |
| 1588 | |
| 1589 | scan = g->strip + 1; |
| 1590 | do { |
| 1591 | s = *scan++; |
| 1592 | switch (OP(s)) { |
| 1593 | case OPLUS_: |
| 1594 | plusnest++; |
| 1595 | break; |
| 1596 | case O_PLUS: |
| 1597 | if (plusnest > maxnest) |
| 1598 | maxnest = plusnest; |
| 1599 | plusnest--; |
| 1600 | break; |
| 1601 | } |
| 1602 | } while (OP(s) != OEND); |
| 1603 | if (plusnest != 0) |
| 1604 | g->iflags |= BAD; |
| 1605 | return(maxnest); |
| 1606 | } |