| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: anag.c,v 1.5 2002/08/11 12:58:09 mdw Exp $ |
| 4 | * |
| 5 | * Main driver for anag |
| 6 | * |
| 7 | * (c) 2001 Mark Wooding |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Anag: a simple wordgame helper. |
| 13 | * |
| 14 | * Anag is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License as published by |
| 16 | * the Free Software Foundation; either version 2 of the License, or |
| 17 | * (at your option) any later version. |
| 18 | * |
| 19 | * Anag is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU General Public License |
| 25 | * along with Anag; if not, write to the Free Software Foundation, |
| 26 | * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. |
| 27 | */ |
| 28 | |
| 29 | /*----- Revision history --------------------------------------------------* |
| 30 | * |
| 31 | * $Log: anag.c,v $ |
| 32 | * Revision 1.5 2002/08/11 12:58:09 mdw |
| 33 | * Added support for regular expression matching, if supported by the C |
| 34 | * library. |
| 35 | * |
| 36 | * Revision 1.4 2001/02/19 19:18:50 mdw |
| 37 | * Minor big fixes to parser. |
| 38 | * |
| 39 | * Revision 1.3 2001/02/16 21:45:19 mdw |
| 40 | * Be more helpful. Improve full help message. Special-case error for |
| 41 | * empty command strings. |
| 42 | * |
| 43 | * Revision 1.2 2001/02/07 09:09:11 mdw |
| 44 | * Fix spurious error when `-file' is used. |
| 45 | * |
| 46 | * Revision 1.1 2001/02/04 17:14:42 mdw |
| 47 | * Initial checkin |
| 48 | * |
| 49 | */ |
| 50 | |
| 51 | /*----- Header files ------------------------------------------------------*/ |
| 52 | |
| 53 | #include "anag.h" |
| 54 | |
| 55 | /*----- Static variables --------------------------------------------------*/ |
| 56 | |
| 57 | static const char *file = DICTIONARY; |
| 58 | |
| 59 | /*----- Help text functions -----------------------------------------------*/ |
| 60 | |
| 61 | static void usage(FILE *fp) |
| 62 | { |
| 63 | pquis(fp, "Usage: $ [-f file] expression\n"); |
| 64 | } |
| 65 | |
| 66 | static void version(FILE *fp) |
| 67 | { |
| 68 | pquis(fp, "$, version " VERSION "\n"); |
| 69 | } |
| 70 | |
| 71 | static void help(FILE *fp) |
| 72 | { |
| 73 | version(fp); |
| 74 | fputc('\n', fp); |
| 75 | usage(fp); |
| 76 | fputs("\n\ |
| 77 | Searches a wordlist, printing all of the words which match an expression.\n\ |
| 78 | \n\ |
| 79 | Options supported are:\n\ |
| 80 | \n\ |
| 81 | -h, --help display this help text\n\ |
| 82 | -v, --version display the program's version number\n\ |
| 83 | -u, --usage display a very brief usage message\n\ |
| 84 | -f, --file FILE read wordlist from FILE, not `" DICTIONARY "'\n\ |
| 85 | \n\ |
| 86 | The basic tests in the expression are:\n\ |
| 87 | \n\ |
| 88 | -anagram WORD matches a full-length anagram\n\ |
| 89 | -subgram WORD matches words which only use letters in WORD\n\ |
| 90 | -wildcard PATTERN matches with wildcards `*' and `?'\n\ |
| 91 | -trackword WORD matches words which can be found in a trackword\n\ |
| 92 | " |
| 93 | #ifdef HAVE_REGCOMP |
| 94 | "\ |
| 95 | -regexp REGEXP matches with an (extended) regular expression\n\ |
| 96 | " |
| 97 | #endif |
| 98 | "\ |
| 99 | \n\ |
| 100 | These simple tests can be combined using the operators `-a', `-o' and `-n'\n\ |
| 101 | (for `and', `or' and `not'; they may also be written `&', `|' and `!' if\n\ |
| 102 | you like), and grouped using parentheses `(' and `)'.\n\ |
| 103 | ", fp); |
| 104 | } |
| 105 | |
| 106 | /*----- The options parser ------------------------------------------------*/ |
| 107 | |
| 108 | /* --- Options table structure --- */ |
| 109 | |
| 110 | struct opt { |
| 111 | const char *name; |
| 112 | unsigned nargs; |
| 113 | unsigned f; |
| 114 | unsigned tag; |
| 115 | }; |
| 116 | |
| 117 | enum { |
| 118 | O_HELP, O_VERSION, O_USAGE, |
| 119 | O_FILE, |
| 120 | O_AND, O_OR, O_NOT, O_LPAREN, O_RPAREN, |
| 121 | O_ANAG, O_SUBG, O_WILD, O_TRACK, O_REGEXP, |
| 122 | O_EOF |
| 123 | }; |
| 124 | |
| 125 | #define OF_SHORT 1u |
| 126 | |
| 127 | static const struct opt opttab[] = { |
| 128 | |
| 129 | /* --- Options -- don't form part of the language --- */ |
| 130 | |
| 131 | { "help", 0, OF_SHORT, O_HELP }, |
| 132 | { "version", 0, OF_SHORT, O_VERSION }, |
| 133 | { "usage", 0, OF_SHORT, O_USAGE }, |
| 134 | { "file", 1, OF_SHORT, O_FILE }, |
| 135 | |
| 136 | /* --- Operators -- provide the basic structure of the language --- * |
| 137 | * |
| 138 | * These are also given magical names by the parser. |
| 139 | */ |
| 140 | |
| 141 | { "and", 0, OF_SHORT, O_AND }, |
| 142 | { "or", 0, OF_SHORT, O_OR }, |
| 143 | { "not", 0, OF_SHORT, O_NOT }, |
| 144 | |
| 145 | /* --- Actual matching oeprations -- do something useful --- */ |
| 146 | |
| 147 | { "anagram", 1, 0, O_ANAG }, |
| 148 | { "subgram", 1, 0, O_SUBG }, |
| 149 | { "wildcard", 1, 0, O_WILD }, |
| 150 | { "trackword", 1, 0, O_TRACK }, |
| 151 | #ifdef HAVE_REGCOMP |
| 152 | { "regexp", 1, 0, O_REGEXP }, |
| 153 | #endif |
| 154 | |
| 155 | /* --- End marker --- */ |
| 156 | |
| 157 | { 0, 0, 0, 0 } |
| 158 | }; |
| 159 | |
| 160 | static int ac; |
| 161 | static const char *const *av; |
| 162 | static int ai; |
| 163 | |
| 164 | /* --- @nextopt@ --- * |
| 165 | * |
| 166 | * Arguments: @const char ***arg@ = where to store the arg pointer |
| 167 | * |
| 168 | * Returns: The tag of the next option. |
| 169 | * |
| 170 | * Use: Scans the next option off the command line. If the option |
| 171 | * doesn't form part of the language, it's processed internally, |
| 172 | * and you'll never see it from here. On exit, the @arg@ |
| 173 | * pointer is set to contain the address of the option scanned, |
| 174 | * followed by its arguments if any. You're expected to know |
| 175 | * how many arguments there are for your option. |
| 176 | */ |
| 177 | |
| 178 | static unsigned nextopt(const char *const **arg) |
| 179 | { |
| 180 | for (;;) { |
| 181 | const struct opt *o, *oo; |
| 182 | size_t sz; |
| 183 | const char *p; |
| 184 | |
| 185 | /* --- Pick the next option off the front --- */ |
| 186 | |
| 187 | *arg = av + ai; |
| 188 | if (ai >= ac) |
| 189 | return (O_EOF); |
| 190 | p = av[ai++]; |
| 191 | |
| 192 | /* --- Cope with various forms of magic --- */ |
| 193 | |
| 194 | if (p[0] != '-') { |
| 195 | if (!p[1]) switch (*p) { |
| 196 | case '&': return (O_AND); |
| 197 | case '|': return (O_OR); |
| 198 | case '!': return (O_NOT); |
| 199 | case '(': return (O_LPAREN); |
| 200 | case ')': return (O_RPAREN); |
| 201 | } |
| 202 | goto bad; |
| 203 | } |
| 204 | |
| 205 | /* --- Now cope with other sorts of weirdies --- * |
| 206 | * |
| 207 | * By the end of this, a leading `-' or `--' will have been stripped. |
| 208 | */ |
| 209 | |
| 210 | p++; |
| 211 | if (!*p) |
| 212 | goto bad; |
| 213 | if (*p == '-') |
| 214 | p++; |
| 215 | if (!*p) { |
| 216 | if (ai < ac) |
| 217 | die("syntax error near `--': rubbish at end of line"); |
| 218 | return (O_EOF); |
| 219 | } |
| 220 | |
| 221 | /* --- Now look the word up in my table --- */ |
| 222 | |
| 223 | sz = strlen(p); |
| 224 | oo = 0; |
| 225 | for (o = opttab; o->name; o++) { |
| 226 | if (strncmp(p, o->name, sz) == 0) { |
| 227 | if (strlen(o->name) == sz || ((o->f & OF_SHORT) && sz == 1)) { |
| 228 | oo = o; |
| 229 | break; |
| 230 | } |
| 231 | if (oo) { |
| 232 | die("ambiguous option name `-%s' (could match `-%s' or `-%s')", |
| 233 | p, oo->name, o->name); |
| 234 | } |
| 235 | oo = o; |
| 236 | } |
| 237 | } |
| 238 | if (!oo) |
| 239 | die("unrecognized option name `-%s'", p); |
| 240 | |
| 241 | /* --- Sort out the arguments --- */ |
| 242 | |
| 243 | if (ai + oo->nargs > ac) |
| 244 | die("too few arguments for `-%s' (need %u)", oo->name, oo->nargs); |
| 245 | ai += oo->nargs; |
| 246 | |
| 247 | /* --- Now process the option --- */ |
| 248 | |
| 249 | switch (oo->tag) { |
| 250 | case O_HELP: |
| 251 | help(stdout); |
| 252 | exit(0); |
| 253 | case O_VERSION: |
| 254 | version(stdout); |
| 255 | exit(0); |
| 256 | case O_USAGE: |
| 257 | usage(stdout); |
| 258 | exit(0); |
| 259 | case O_FILE: |
| 260 | file = (*arg)[1]; |
| 261 | break; |
| 262 | default: |
| 263 | return (oo->tag); |
| 264 | } |
| 265 | continue; |
| 266 | bad: |
| 267 | die("syntax error near `%s': unknown token type", av[ai - 1]); |
| 268 | } |
| 269 | } |
| 270 | |
| 271 | /*----- Node types for operators ------------------------------------------*/ |
| 272 | |
| 273 | /* --- Node structures --- */ |
| 274 | |
| 275 | typedef struct node_bin { |
| 276 | node n; |
| 277 | node *left; |
| 278 | node *right; |
| 279 | } node_bin; |
| 280 | |
| 281 | typedef struct node_un { |
| 282 | node n; |
| 283 | node *arg; |
| 284 | } node_un; |
| 285 | |
| 286 | /* --- Node functions --- */ |
| 287 | |
| 288 | static int n_or(node *nn, const char *p, size_t sz) |
| 289 | { |
| 290 | node_bin *n = (node_bin *)nn; |
| 291 | return (n->left->func(n->left, p, sz) || n->right->func(n->right, p, sz)); |
| 292 | } |
| 293 | |
| 294 | static int n_and(node *nn, const char *p, size_t sz) |
| 295 | { |
| 296 | node_bin *n = (node_bin *)nn; |
| 297 | return (n->left->func(n->left, p, sz) && n->right->func(n->right, p, sz)); |
| 298 | } |
| 299 | |
| 300 | static int n_not(node *nn, const char *p, size_t sz) |
| 301 | { |
| 302 | node_un *n = (node_un *)nn; |
| 303 | return (!n->arg->func(n->arg, p, sz)); |
| 304 | } |
| 305 | |
| 306 | /*----- Parser for the expression syntax ----------------------------------*/ |
| 307 | |
| 308 | /* --- A parser context --- */ |
| 309 | |
| 310 | typedef struct p_ctx { |
| 311 | unsigned t; |
| 312 | const char *const *a; |
| 313 | } p_ctx; |
| 314 | |
| 315 | /* --- Parser structure --- * |
| 316 | * |
| 317 | * This is a simple recursive descent parser. The context retains |
| 318 | * information about the current token. Each function is passed the address |
| 319 | * of a node pointer to fill in. This simplifies the binary operator code |
| 320 | * somewhat, relative to returning pointers to node trees. |
| 321 | */ |
| 322 | |
| 323 | static void p_expr(p_ctx *p, node **/*nn*/); |
| 324 | |
| 325 | static void p_next(p_ctx *p) |
| 326 | { |
| 327 | static const char *const eof[] = { "<end>", 0 }; |
| 328 | p->t = nextopt(&p->a); |
| 329 | if (p->t == O_EOF) |
| 330 | p->a = eof; |
| 331 | } |
| 332 | |
| 333 | static void p_factor(p_ctx *p, node **nn) |
| 334 | { |
| 335 | node_un *n; |
| 336 | if (p->t == O_LPAREN) { |
| 337 | p_next(p); |
| 338 | p_expr(p, nn); |
| 339 | if (p->t != O_RPAREN) |
| 340 | die("syntax error near `%s': missing `)'", *p->a); |
| 341 | p_next(p); |
| 342 | } else if (p->t == O_NOT) { |
| 343 | n = xmalloc(sizeof(node_un)); |
| 344 | n->n.func = n_not; |
| 345 | *nn = &n->n; |
| 346 | p_next(p); |
| 347 | p_factor(p, &n->arg); |
| 348 | } else { |
| 349 | switch (p->t) { |
| 350 | case O_ANAG: *nn = anagram(p->a + 1); break; |
| 351 | case O_SUBG: *nn = subgram(p->a + 1); break; |
| 352 | case O_WILD: *nn = wildcard(p->a + 1); break; |
| 353 | case O_TRACK: *nn = trackword(p->a + 1); break; |
| 354 | #ifdef HAVE_REGCOMP |
| 355 | case O_REGEXP: *nn = regexp(p->a + 1); break; |
| 356 | #endif |
| 357 | default: die("syntax error near `%s': unexpected token", *p->a); |
| 358 | } |
| 359 | p_next(p); |
| 360 | } |
| 361 | } |
| 362 | |
| 363 | static void p_term(p_ctx *p, node **nn) |
| 364 | { |
| 365 | node_bin *n; |
| 366 | for (;;) { |
| 367 | p_factor(p, nn); |
| 368 | switch (p->t) { |
| 369 | case O_AND: |
| 370 | p_next(p); |
| 371 | default: |
| 372 | break; |
| 373 | case O_RPAREN: |
| 374 | case O_OR: |
| 375 | case O_EOF: |
| 376 | return; |
| 377 | } |
| 378 | n = xmalloc(sizeof(node_bin)); |
| 379 | n->left = *nn; |
| 380 | n->n.func = n_and; |
| 381 | *nn = &n->n; |
| 382 | nn = &n->right; |
| 383 | } |
| 384 | } |
| 385 | |
| 386 | static void p_expr(p_ctx *p, node **nn) |
| 387 | { |
| 388 | node_bin *n; |
| 389 | for (;;) { |
| 390 | p_term(p, nn); |
| 391 | if (p->t != O_OR) |
| 392 | break; |
| 393 | p_next(p); |
| 394 | n = xmalloc(sizeof(node_bin)); |
| 395 | n->left = *nn; |
| 396 | n->n.func = n_or; |
| 397 | *nn = &n->n; |
| 398 | nn = &n->right; |
| 399 | } |
| 400 | } |
| 401 | |
| 402 | /* --- @p_argv@ --- * |
| 403 | * |
| 404 | * Arguments: @int argc@ = number of command-line arguments |
| 405 | * @const char *const argv[]@ = vectoor of arguments |
| 406 | * |
| 407 | * Returns: A compiled node, parsed from the arguments. |
| 408 | * |
| 409 | * Use: Does the donkey-work of parsing a command-line. |
| 410 | */ |
| 411 | |
| 412 | static node *p_argv(int argc, const char *const argv[]) |
| 413 | { |
| 414 | p_ctx p; |
| 415 | node *n; |
| 416 | |
| 417 | av = argv; |
| 418 | ac = argc; |
| 419 | ai = 1; |
| 420 | p_next(&p); |
| 421 | if (p.t == O_EOF) { |
| 422 | usage(stderr); |
| 423 | pquis(stderr, "(Run `$ --help' for more detail.)\n"); |
| 424 | exit(EXIT_FAILURE); |
| 425 | } |
| 426 | p_expr(&p, &n); |
| 427 | if (p.t != O_EOF) { |
| 428 | die("syntax error near `%s': rubbish at end of line (too many `)'s?)", |
| 429 | *p.a); |
| 430 | } |
| 431 | return (n); |
| 432 | } |
| 433 | |
| 434 | /*----- Main code ---------------------------------------------------------*/ |
| 435 | |
| 436 | /* --- @main@ --- * |
| 437 | * |
| 438 | * Arguments: @int argc@ = number of command-line arguments |
| 439 | * @char *argv[]@ = vector of argument words |
| 440 | * |
| 441 | * Returns: Zero on success, nonzero on failure. |
| 442 | * |
| 443 | * Use: Picks entries from a word list which match particular |
| 444 | * expressions. This might be of assistance to word-game types. |
| 445 | */ |
| 446 | |
| 447 | int main(int argc, char *argv[]) |
| 448 | { |
| 449 | node *n; |
| 450 | FILE *fp; |
| 451 | dstr d = DSTR_INIT; |
| 452 | char *p, *q, *l; |
| 453 | |
| 454 | ego(argv[0]); |
| 455 | n = p_argv(argc, (const char *const *)argv); |
| 456 | |
| 457 | if ((fp = fopen(file, "r")) == 0) |
| 458 | die("error opening `%s': %s", file, strerror(errno)); |
| 459 | for (;;) { |
| 460 | dstr_reset(&d); |
| 461 | if (dstr_putline(&d, fp) < 0) |
| 462 | break; |
| 463 | l = d.buf + d.len; |
| 464 | for (p = q = d.buf; p < l; p++) { |
| 465 | if (!isalnum((unsigned char)*p)) |
| 466 | continue; |
| 467 | *q++ = tolower((unsigned char)*p); |
| 468 | } |
| 469 | *q = 0; |
| 470 | d.len = q - d.buf; |
| 471 | if (n->func(n, d.buf, d.len)) { |
| 472 | fwrite(d.buf, 1, d.len, stdout); |
| 473 | fputc('\n', stdout); |
| 474 | } |
| 475 | } |
| 476 | if (!feof(fp)) |
| 477 | die("error reading `%s': %s", file, strerror(errno)); |
| 478 | fclose(fp); |
| 479 | return (0); |
| 480 | } |
| 481 | |
| 482 | /*----- That's all, folks -------------------------------------------------*/ |