| 1 | /* |
| 2 | * Internal interface definitions, etc., for the reg package |
| 3 | * |
| 4 | * Copyright (c) 1998, 1999 Henry Spencer. All rights reserved. |
| 5 | * |
| 6 | * Development of this software was funded, in part, by Cray Research Inc., |
| 7 | * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics |
| 8 | * Corporation, none of whom are responsible for the results. The author |
| 9 | * thanks all of them. |
| 10 | * |
| 11 | * Redistribution and use in source and binary forms -- with or without |
| 12 | * modification -- are permitted for any purpose, provided that |
| 13 | * redistributions in source form retain this entire copyright notice and |
| 14 | * indicate the origin and nature of any modifications. |
| 15 | * |
| 16 | * I'd appreciate being given credit for this package in the documentation |
| 17 | * of software which uses it, but that is not a requirement. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, |
| 20 | * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY |
| 21 | * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL |
| 22 | * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| 23 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| 24 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; |
| 25 | * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 26 | * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR |
| 27 | * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF |
| 28 | * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 29 | * |
| 30 | * $Id$ |
| 31 | */ |
| 32 | |
| 33 | |
| 34 | |
| 35 | /* |
| 36 | * Environmental customization. It should not (I hope) be necessary to |
| 37 | * alter the file you are now reading -- regcustom.h should handle it all, |
| 38 | * given care here and elsewhere. |
| 39 | */ |
| 40 | #include "regcustom.h" |
| 41 | |
| 42 | |
| 43 | |
| 44 | /* |
| 45 | * Things that regcustom.h might override. |
| 46 | */ |
| 47 | |
| 48 | /* assertions */ |
| 49 | #ifndef assert |
| 50 | #ifndef REG_DEBUG |
| 51 | # ifndef NDEBUG |
| 52 | # define NDEBUG /* no assertions */ |
| 53 | # endif |
| 54 | #endif |
| 55 | #include <assert.h> |
| 56 | #endif |
| 57 | |
| 58 | /* voids */ |
| 59 | #ifndef DISCARD |
| 60 | #define DISCARD void /* for throwing values away */ |
| 61 | #endif |
| 62 | #ifndef VS |
| 63 | #define VS(x) ((void *)(x)) /* cast something to generic ptr */ |
| 64 | #endif |
| 65 | |
| 66 | /* function-pointer declarator */ |
| 67 | #ifndef FUNCPTR |
| 68 | #define FUNCPTR(name, args) (*name) args |
| 69 | #endif |
| 70 | |
| 71 | /* memory allocation */ |
| 72 | #ifndef MALLOC |
| 73 | #define MALLOC(n) malloc(n) |
| 74 | #endif |
| 75 | #ifndef REALLOC |
| 76 | #define REALLOC(p, n) realloc(VS(p), n) |
| 77 | #endif |
| 78 | #ifndef FREE |
| 79 | #define FREE(p) free(VS(p)) |
| 80 | #endif |
| 81 | |
| 82 | /* want size of a char in bits, and max value in bounded quantifiers */ |
| 83 | #ifndef CHAR_BIT |
| 84 | #include <limits.h> |
| 85 | #endif |
| 86 | #ifndef _POSIX2_RE_DUP_MAX |
| 87 | #define _POSIX2_RE_DUP_MAX 255 /* normally from <limits.h> */ |
| 88 | #endif |
| 89 | |
| 90 | |
| 91 | |
| 92 | /* |
| 93 | * misc |
| 94 | */ |
| 95 | |
| 96 | #define NOTREACHED 0 |
| 97 | #define xxx 1 |
| 98 | |
| 99 | #define DUPMAX _POSIX2_RE_DUP_MAX |
| 100 | #define INFINITY (DUPMAX+1) |
| 101 | |
| 102 | #define REMAGIC 0xfed7 /* magic number for main struct */ |
| 103 | |
| 104 | |
| 105 | |
| 106 | /* |
| 107 | * debugging facilities |
| 108 | */ |
| 109 | #ifdef REG_DEBUG |
| 110 | /* FDEBUG does finite-state tracing */ |
| 111 | #define FDEBUG(arglist) { if (v->eflags®_FTRACE) printf arglist; } |
| 112 | /* MDEBUG does higher-level tracing */ |
| 113 | #define MDEBUG(arglist) { if (v->eflags®_MTRACE) printf arglist; } |
| 114 | #else |
| 115 | #define FDEBUG(arglist) {} |
| 116 | #define MDEBUG(arglist) {} |
| 117 | #endif |
| 118 | |
| 119 | |
| 120 | |
| 121 | /* |
| 122 | * bitmap manipulation |
| 123 | */ |
| 124 | #define UBITS (CHAR_BIT * sizeof(unsigned)) |
| 125 | #define BSET(uv, sn) ((uv)[(sn)/UBITS] |= (unsigned)1 << ((sn)%UBITS)) |
| 126 | #define ISBSET(uv, sn) ((uv)[(sn)/UBITS] & ((unsigned)1 << ((sn)%UBITS))) |
| 127 | |
| 128 | |
| 129 | |
| 130 | /* |
| 131 | * We dissect a chr into byts for colormap table indexing. Here we define |
| 132 | * a byt, which will be the same as a byte on most machines... The exact |
| 133 | * size of a byt is not critical, but about 8 bits is good, and extraction |
| 134 | * of 8-bit chunks is sometimes especially fast. |
| 135 | */ |
| 136 | #ifndef BYTBITS |
| 137 | #define BYTBITS 8 /* bits in a byt */ |
| 138 | #endif |
| 139 | #define BYTTAB (1<<BYTBITS) /* size of table with one entry per byt |
| 140 | * value */ |
| 141 | #define BYTMASK (BYTTAB-1) /* bit mask for byt */ |
| 142 | #define NBYTS ((CHRBITS+BYTBITS-1)/BYTBITS) |
| 143 | /* the definition of GETCOLOR(), below, assumes NBYTS <= 4 */ |
| 144 | |
| 145 | |
| 146 | |
| 147 | /* |
| 148 | * As soon as possible, we map chrs into equivalence classes -- "colors" -- |
| 149 | * which are of much more manageable number. |
| 150 | */ |
| 151 | typedef short color; /* colors of characters */ |
| 152 | typedef int pcolor; /* what color promotes to */ |
| 153 | |
| 154 | #define COLORLESS (-1) /* impossible color */ |
| 155 | #define WHITE 0 /* default color, parent of all others */ |
| 156 | |
| 157 | |
| 158 | |
| 159 | /* |
| 160 | * A colormap is a tree -- more precisely, a DAG -- indexed at each level |
| 161 | * by a byt of the chr, to map the chr to a color efficiently. Because |
| 162 | * lower sections of the tree can be shared, it can exploit the usual |
| 163 | * sparseness of such a mapping table. The tree is always NBYTS levels |
| 164 | * deep (in the past it was shallower during construction but was "filled" |
| 165 | * to full depth at the end of that); areas that are unaltered as yet point |
| 166 | * to "fill blocks" which are entirely WHITE in color. |
| 167 | */ |
| 168 | |
| 169 | /* the tree itself */ |
| 170 | struct colors |
| 171 | { |
| 172 | color ccolor[BYTTAB]; |
| 173 | }; |
| 174 | struct ptrs |
| 175 | { |
| 176 | union tree *pptr[BYTTAB]; |
| 177 | }; |
| 178 | union tree |
| 179 | { |
| 180 | struct colors colors; |
| 181 | struct ptrs ptrs; |
| 182 | }; |
| 183 | |
| 184 | #define tcolor colors.ccolor |
| 185 | #define tptr ptrs.pptr |
| 186 | |
| 187 | /* internal per-color structure for the color machinery */ |
| 188 | struct colordesc |
| 189 | { |
| 190 | uchr nchrs; /* number of chars of this color */ |
| 191 | color sub; /* open subcolor (if any); free chain ptr */ |
| 192 | #define NOSUB COLORLESS |
| 193 | struct arc *arcs; /* color chain */ |
| 194 | int flags; |
| 195 | #define FREECOL 01 /* currently free */ |
| 196 | #define PSEUDO 02 /* pseudocolor, no real chars */ |
| 197 | #define UNUSEDCOLOR(cd) ((cd)->flags&FREECOL) |
| 198 | union tree *block; /* block of solid color, if any */ |
| 199 | }; |
| 200 | |
| 201 | /* the color map itself */ |
| 202 | struct colormap |
| 203 | { |
| 204 | int magic; |
| 205 | #define CMMAGIC 0x876 |
| 206 | struct vars *v; /* for compile error reporting */ |
| 207 | size_t ncds; /* number of colordescs */ |
| 208 | size_t max; /* highest in use */ |
| 209 | color free; /* beginning of free chain (if non-0) */ |
| 210 | struct colordesc *cd; |
| 211 | #define CDEND(cm) (&(cm)->cd[(cm)->max + 1]) |
| 212 | #define NINLINECDS ((size_t)10) |
| 213 | struct colordesc cdspace[NINLINECDS]; |
| 214 | union tree tree[NBYTS]; /* tree top, plus fill blocks */ |
| 215 | }; |
| 216 | |
| 217 | /* optimization magic to do fast chr->color mapping */ |
| 218 | #define B0(c) ((c) & BYTMASK) |
| 219 | #define B1(c) (((c)>>BYTBITS) & BYTMASK) |
| 220 | #define B2(c) (((c)>>(2*BYTBITS)) & BYTMASK) |
| 221 | #define B3(c) (((c)>>(3*BYTBITS)) & BYTMASK) |
| 222 | #if NBYTS == 1 |
| 223 | #define GETCOLOR(cm, c) ((cm)->tree->tcolor[B0(c)]) |
| 224 | #endif |
| 225 | /* beware, for NBYTS>1, GETCOLOR() is unsafe -- 2nd arg used repeatedly */ |
| 226 | #if NBYTS == 2 |
| 227 | #define GETCOLOR(cm, c) ((cm)->tree->tptr[B1(c)]->tcolor[B0(c)]) |
| 228 | #endif |
| 229 | #if NBYTS == 4 |
| 230 | #define GETCOLOR(cm, c) ((cm)->tree->tptr[B3(c)]->tptr[B2(c)]->tptr[B1(c)]->tcolor[B0(c)]) |
| 231 | #endif |
| 232 | |
| 233 | |
| 234 | |
| 235 | /* |
| 236 | * Interface definitions for locale-interface functions in locale.c. |
| 237 | * Multi-character collating elements (MCCEs) cause most of the trouble. |
| 238 | */ |
| 239 | struct cvec |
| 240 | { |
| 241 | int nchrs; /* number of chrs */ |
| 242 | int chrspace; /* number of chrs possible */ |
| 243 | chr *chrs; /* pointer to vector of chrs */ |
| 244 | int nranges; /* number of ranges (chr pairs) */ |
| 245 | int rangespace; /* number of chrs possible */ |
| 246 | chr *ranges; /* pointer to vector of chr pairs */ |
| 247 | int nmcces; /* number of MCCEs */ |
| 248 | int mccespace; /* number of MCCEs possible */ |
| 249 | int nmccechrs; /* number of chrs used for MCCEs */ |
| 250 | chr *mcces[1]; /* pointers to 0-terminated MCCEs */ |
| 251 | /* and both batches of chrs are on the end */ |
| 252 | }; |
| 253 | |
| 254 | /* caution: this value cannot be changed easily */ |
| 255 | #define MAXMCCE 2 /* length of longest MCCE */ |
| 256 | |
| 257 | |
| 258 | |
| 259 | /* |
| 260 | * definitions for NFA internal representation |
| 261 | * |
| 262 | * Having a "from" pointer within each arc may seem redundant, but it |
| 263 | * saves a lot of hassle. |
| 264 | */ |
| 265 | struct state; |
| 266 | |
| 267 | struct arc |
| 268 | { |
| 269 | int type; |
| 270 | #define ARCFREE '\0' |
| 271 | color co; |
| 272 | struct state *from; /* where it's from (and contained within) */ |
| 273 | struct state *to; /* where it's to */ |
| 274 | struct arc *outchain; /* *from's outs chain or free chain */ |
| 275 | #define freechain outchain |
| 276 | struct arc *inchain; /* *to's ins chain */ |
| 277 | struct arc *colorchain; /* color's arc chain */ |
| 278 | }; |
| 279 | |
| 280 | struct arcbatch |
| 281 | { /* for bulk allocation of arcs */ |
| 282 | struct arcbatch *next; |
| 283 | #define ABSIZE 10 |
| 284 | struct arc a[ABSIZE]; |
| 285 | }; |
| 286 | |
| 287 | struct state |
| 288 | { |
| 289 | int no; |
| 290 | #define FREESTATE (-1) |
| 291 | char flag; /* marks special states */ |
| 292 | int nins; /* number of inarcs */ |
| 293 | struct arc *ins; /* chain of inarcs */ |
| 294 | int nouts; /* number of outarcs */ |
| 295 | struct arc *outs; /* chain of outarcs */ |
| 296 | struct arc *free; /* chain of free arcs */ |
| 297 | struct state *tmp; /* temporary for traversal algorithms */ |
| 298 | struct state *next; /* chain for traversing all */ |
| 299 | struct state *prev; /* back chain */ |
| 300 | struct arcbatch oas; /* first arcbatch, avoid malloc in easy |
| 301 | * case */ |
| 302 | int noas; /* number of arcs used in first arcbatch */ |
| 303 | }; |
| 304 | |
| 305 | struct nfa |
| 306 | { |
| 307 | struct state *pre; /* pre-initial state */ |
| 308 | struct state *init; /* initial state */ |
| 309 | struct state *final; /* final state */ |
| 310 | struct state *post; /* post-final state */ |
| 311 | int nstates; /* for numbering states */ |
| 312 | struct state *states; /* state-chain header */ |
| 313 | struct state *slast; /* tail of the chain */ |
| 314 | struct state *free; /* free list */ |
| 315 | struct colormap *cm; /* the color map */ |
| 316 | color bos[2]; /* colors, if any, assigned to BOS and BOL */ |
| 317 | color eos[2]; /* colors, if any, assigned to EOS and EOL */ |
| 318 | struct vars *v; /* simplifies compile error reporting */ |
| 319 | struct nfa *parent; /* parent NFA, if any */ |
| 320 | }; |
| 321 | |
| 322 | |
| 323 | |
| 324 | /* |
| 325 | * definitions for compacted NFA |
| 326 | */ |
| 327 | struct carc |
| 328 | { |
| 329 | color co; /* COLORLESS is list terminator */ |
| 330 | int to; /* state number */ |
| 331 | }; |
| 332 | |
| 333 | struct cnfa |
| 334 | { |
| 335 | int nstates; /* number of states */ |
| 336 | int ncolors; /* number of colors */ |
| 337 | int flags; |
| 338 | #define HASLACONS 01 /* uses lookahead constraints */ |
| 339 | int pre; /* setup state number */ |
| 340 | int post; /* teardown state number */ |
| 341 | color bos[2]; /* colors, if any, assigned to BOS and BOL */ |
| 342 | color eos[2]; /* colors, if any, assigned to EOS and EOL */ |
| 343 | struct carc **states; /* vector of pointers to outarc lists */ |
| 344 | struct carc *arcs; /* the area for the lists */ |
| 345 | }; |
| 346 | |
| 347 | #define ZAPCNFA(cnfa) ((cnfa).nstates = 0) |
| 348 | #define NULLCNFA(cnfa) ((cnfa).nstates == 0) |
| 349 | |
| 350 | |
| 351 | |
| 352 | /* |
| 353 | * subexpression tree |
| 354 | */ |
| 355 | struct subre |
| 356 | { |
| 357 | char op; /* '|', '.' (concat), 'b' (backref), '(', |
| 358 | * '=' */ |
| 359 | char flags; |
| 360 | #define LONGER 01 /* prefers longer match */ |
| 361 | #define SHORTER 02 /* prefers shorter match */ |
| 362 | #define MIXED 04 /* mixed preference below */ |
| 363 | #define CAP 010 /* capturing parens below */ |
| 364 | #define BACKR 020 /* back reference below */ |
| 365 | #define INUSE 0100 /* in use in final tree */ |
| 366 | #define LOCAL 03 /* bits which may not propagate up */ |
| 367 | #define LMIX(f) ((f)<<2) /* LONGER -> MIXED */ |
| 368 | #define SMIX(f) ((f)<<1) /* SHORTER -> MIXED */ |
| 369 | #define UP(f) (((f)&~LOCAL) | (LMIX(f) & SMIX(f) & MIXED)) |
| 370 | #define MESSY(f) ((f)&(MIXED|CAP|BACKR)) |
| 371 | #define PREF(f) ((f)&LOCAL) |
| 372 | #define PREF2(f1, f2) ((PREF(f1) != 0) ? PREF(f1) : PREF(f2)) |
| 373 | #define COMBINE(f1, f2) (UP((f1)|(f2)) | PREF2(f1, f2)) |
| 374 | short retry; /* index into retry memory */ |
| 375 | int subno; /* subexpression number (for 'b' and '(') */ |
| 376 | short min; /* min repetitions, for backref only */ |
| 377 | short max; /* max repetitions, for backref only */ |
| 378 | struct subre *left; /* left child, if any (also freelist |
| 379 | * chain) */ |
| 380 | struct subre *right; /* right child, if any */ |
| 381 | struct state *begin; /* outarcs from here... */ |
| 382 | struct state *end; /* ...ending in inarcs here */ |
| 383 | struct cnfa cnfa; /* compacted NFA, if any */ |
| 384 | struct subre *chain; /* for bookkeeping and error cleanup */ |
| 385 | }; |
| 386 | |
| 387 | |
| 388 | |
| 389 | /* |
| 390 | * table of function pointers for generic manipulation functions |
| 391 | * A regex_t's re_fns points to one of these. |
| 392 | */ |
| 393 | struct fns |
| 394 | { |
| 395 | void FUNCPTR(free, (regex_t *)); |
| 396 | }; |
| 397 | |
| 398 | |
| 399 | |
| 400 | /* |
| 401 | * the insides of a regex_t, hidden behind a void * |
| 402 | */ |
| 403 | struct guts |
| 404 | { |
| 405 | int magic; |
| 406 | #define GUTSMAGIC 0xfed9 |
| 407 | int cflags; /* copy of compile flags */ |
| 408 | long info; /* copy of re_info */ |
| 409 | size_t nsub; /* copy of re_nsub */ |
| 410 | struct subre *tree; |
| 411 | struct cnfa search; /* for fast preliminary search */ |
| 412 | int ntree; |
| 413 | struct colormap cmap; |
| 414 | int FUNCPTR(compare, (const chr *, const chr *, size_t)); |
| 415 | struct subre *lacons; /* lookahead-constraint vector */ |
| 416 | int nlacons; /* size of lacons */ |
| 417 | }; |