chiark / gitweb /
Allow `.' as a wildcard. Makes Scrabble playing easier.
[anag] / anag.c
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6e403221 1/* -*-c-*-
2 *
345f33ea 3 * $Id: anag.c,v 1.8 2004/04/08 01:36:19 mdw Exp $
6e403221 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
6e403221 29/*----- Header files ------------------------------------------------------*/
30
31#include "anag.h"
32
33/*----- Static variables --------------------------------------------------*/
34
35static const char *file = DICTIONARY;
36
37/*----- Help text functions -----------------------------------------------*/
38
39static void usage(FILE *fp)
40{
41 pquis(fp, "Usage: $ [-f file] expression\n");
42}
43
44static void version(FILE *fp)
45{
46 pquis(fp, "$, version " VERSION "\n");
47}
48
49static void help(FILE *fp)
50{
51 version(fp);
52 fputc('\n', fp);
53 usage(fp);
54 fputs("\n\
55Searches a wordlist, printing all of the words which match an expression.\n\
2668675c 56\n\
57Options supported are:\n\
58\n\
59-h, --help display this help text\n\
60-v, --version display the program's version number\n\
61-u, --usage display a very brief usage message\n\
62-f, --file FILE read wordlist from FILE, not `" DICTIONARY "'\n\
63\n\
6e403221 64The basic tests in the expression are:\n\
65\n\
66-anagram WORD matches a full-length anagram\n\
67-subgram WORD matches words which only use letters in WORD\n\
68-wildcard PATTERN matches with wildcards `*' and `?'\n\
69-trackword WORD matches words which can be found in a trackword\n\
fe9969ff 70-mono PATTERN matches words isomorphic to the given PATTERN\n\
a10122de 71"
72#ifdef HAVE_REGCOMP
73"\
74-regexp REGEXP matches with an (extended) regular expression\n\
75"
76#endif
d9af4a2b 77#ifdef HAVE_PCRE
78"\
79-pcre REGEXP matches with a Perl-like regular expression\n\
80"
81#endif
a10122de 82"\
6e403221 83\n\
84These simple tests can be combined using the operators `-a', `-o' and `-n'\n\
85(for `and', `or' and `not'; they may also be written `&', `|' and `!' if\n\
86you like), and grouped using parentheses `(' and `)'.\n\
d9af4a2b 87", fp); /*"*/
6e403221 88}
89
90/*----- The options parser ------------------------------------------------*/
91
92/* --- Options table structure --- */
93
94struct opt {
95 const char *name;
96 unsigned nargs;
97 unsigned f;
98 unsigned tag;
99};
100
101enum {
102 O_HELP, O_VERSION, O_USAGE,
103 O_FILE,
104 O_AND, O_OR, O_NOT, O_LPAREN, O_RPAREN,
d9af4a2b 105 O_ANAG, O_SUBG, O_WILD, O_TRACK, O_REGEXP, O_PCRE, O_MONO,
6e403221 106 O_EOF
107};
108
109#define OF_SHORT 1u
110
111static const struct opt opttab[] = {
112
113 /* --- Options -- don't form part of the language --- */
114
115 { "help", 0, OF_SHORT, O_HELP },
116 { "version", 0, OF_SHORT, O_VERSION },
117 { "usage", 0, OF_SHORT, O_USAGE },
118 { "file", 1, OF_SHORT, O_FILE },
119
120 /* --- Operators -- provide the basic structure of the language --- *
121 *
122 * These are also given magical names by the parser.
123 */
124
125 { "and", 0, OF_SHORT, O_AND },
126 { "or", 0, OF_SHORT, O_OR },
127 { "not", 0, OF_SHORT, O_NOT },
128
129 /* --- Actual matching oeprations -- do something useful --- */
130
131 { "anagram", 1, 0, O_ANAG },
132 { "subgram", 1, 0, O_SUBG },
133 { "wildcard", 1, 0, O_WILD },
134 { "trackword", 1, 0, O_TRACK },
fe9969ff 135 { "mono", 1, 0, O_MONO },
a10122de 136#ifdef HAVE_REGCOMP
137 { "regexp", 1, 0, O_REGEXP },
138#endif
d9af4a2b 139#ifdef HAVE_PCRE
140 { "pcre", 1, 0, O_PCRE },
141#endif
6e403221 142
143 /* --- End marker --- */
144
145 { 0, 0, 0, 0 }
146};
147
148static int ac;
149static const char *const *av;
150static int ai;
151
152/* --- @nextopt@ --- *
153 *
154 * Arguments: @const char ***arg@ = where to store the arg pointer
155 *
156 * Returns: The tag of the next option.
157 *
158 * Use: Scans the next option off the command line. If the option
159 * doesn't form part of the language, it's processed internally,
160 * and you'll never see it from here. On exit, the @arg@
161 * pointer is set to contain the address of the option scanned,
162 * followed by its arguments if any. You're expected to know
163 * how many arguments there are for your option.
164 */
165
166static unsigned nextopt(const char *const **arg)
167{
168 for (;;) {
169 const struct opt *o, *oo;
170 size_t sz;
171 const char *p;
172
173 /* --- Pick the next option off the front --- */
174
175 *arg = av + ai;
176 if (ai >= ac)
177 return (O_EOF);
178 p = av[ai++];
179
180 /* --- Cope with various forms of magic --- */
181
182 if (p[0] != '-') {
183 if (!p[1]) switch (*p) {
184 case '&': return (O_AND);
185 case '|': return (O_OR);
186 case '!': return (O_NOT);
187 case '(': return (O_LPAREN);
188 case ')': return (O_RPAREN);
189 }
190 goto bad;
191 }
192
193 /* --- Now cope with other sorts of weirdies --- *
194 *
195 * By the end of this, a leading `-' or `--' will have been stripped.
196 */
197
198 p++;
199 if (!*p)
200 goto bad;
201 if (*p == '-')
202 p++;
203 if (!*p) {
204 if (ai < ac)
205 die("syntax error near `--': rubbish at end of line");
206 return (O_EOF);
207 }
208
209 /* --- Now look the word up in my table --- */
210
211 sz = strlen(p);
212 oo = 0;
213 for (o = opttab; o->name; o++) {
214 if (strncmp(p, o->name, sz) == 0) {
215 if (strlen(o->name) == sz || ((o->f & OF_SHORT) && sz == 1)) {
216 oo = o;
217 break;
218 }
219 if (oo) {
220 die("ambiguous option name `-%s' (could match `-%s' or `-%s')",
221 p, oo->name, o->name);
222 }
223 oo = o;
224 }
225 }
226 if (!oo)
227 die("unrecognized option name `-%s'", p);
228
229 /* --- Sort out the arguments --- */
230
231 if (ai + oo->nargs > ac)
232 die("too few arguments for `-%s' (need %u)", oo->name, oo->nargs);
233 ai += oo->nargs;
234
235 /* --- Now process the option --- */
236
237 switch (oo->tag) {
238 case O_HELP:
239 help(stdout);
240 exit(0);
241 case O_VERSION:
242 version(stdout);
243 exit(0);
244 case O_USAGE:
245 usage(stdout);
246 exit(0);
247 case O_FILE:
248 file = (*arg)[1];
249 break;
250 default:
251 return (oo->tag);
252 }
60dffc01 253 continue;
6e403221 254 bad:
255 die("syntax error near `%s': unknown token type", av[ai - 1]);
256 }
257}
258
259/*----- Node types for operators ------------------------------------------*/
260
261/* --- Node structures --- */
262
263typedef struct node_bin {
264 node n;
265 node *left;
266 node *right;
267} node_bin;
268
269typedef struct node_un {
270 node n;
271 node *arg;
272} node_un;
273
274/* --- Node functions --- */
275
276static int n_or(node *nn, const char *p, size_t sz)
277{
278 node_bin *n = (node_bin *)nn;
279 return (n->left->func(n->left, p, sz) || n->right->func(n->right, p, sz));
280}
281
282static int n_and(node *nn, const char *p, size_t sz)
283{
284 node_bin *n = (node_bin *)nn;
285 return (n->left->func(n->left, p, sz) && n->right->func(n->right, p, sz));
286}
287
288static int n_not(node *nn, const char *p, size_t sz)
289{
290 node_un *n = (node_un *)nn;
291 return (!n->arg->func(n->arg, p, sz));
292}
293
294/*----- Parser for the expression syntax ----------------------------------*/
295
296/* --- A parser context --- */
297
298typedef struct p_ctx {
299 unsigned t;
300 const char *const *a;
301} p_ctx;
302
303/* --- Parser structure --- *
304 *
305 * This is a simple recursive descent parser. The context retains
306 * information about the current token. Each function is passed the address
307 * of a node pointer to fill in. This simplifies the binary operator code
308 * somewhat, relative to returning pointers to node trees.
309 */
310
311static void p_expr(p_ctx *p, node **/*nn*/);
312
313static void p_next(p_ctx *p)
314{
315 static const char *const eof[] = { "<end>", 0 };
316 p->t = nextopt(&p->a);
317 if (p->t == O_EOF)
318 p->a = eof;
319}
320
321static void p_factor(p_ctx *p, node **nn)
322{
323 node_un *n;
324 if (p->t == O_LPAREN) {
325 p_next(p);
326 p_expr(p, nn);
327 if (p->t != O_RPAREN)
1d2d1062 328 die("syntax error near `%s': missing `)'", *p->a);
6e403221 329 p_next(p);
330 } else if (p->t == O_NOT) {
331 n = xmalloc(sizeof(node_un));
332 n->n.func = n_not;
333 *nn = &n->n;
334 p_next(p);
335 p_factor(p, &n->arg);
336 } else {
337 switch (p->t) {
338 case O_ANAG: *nn = anagram(p->a + 1); break;
339 case O_SUBG: *nn = subgram(p->a + 1); break;
340 case O_WILD: *nn = wildcard(p->a + 1); break;
341 case O_TRACK: *nn = trackword(p->a + 1); break;
a10122de 342#ifdef HAVE_REGCOMP
343 case O_REGEXP: *nn = regexp(p->a + 1); break;
344#endif
d9af4a2b 345#ifdef HAVE_PCRE
346 case O_PCRE: *nn = pcrenode(p->a + 1); break;
347#endif
fe9969ff 348 case O_MONO: *nn = mono(p->a + 1); break;
6e403221 349 default: die("syntax error near `%s': unexpected token", *p->a);
350 }
351 p_next(p);
352 }
353}
354
355static void p_term(p_ctx *p, node **nn)
356{
357 node_bin *n;
358 for (;;) {
359 p_factor(p, nn);
360 switch (p->t) {
361 case O_AND:
362 p_next(p);
363 default:
364 break;
6e403221 365 case O_RPAREN:
366 case O_OR:
367 case O_EOF:
368 return;
369 }
370 n = xmalloc(sizeof(node_bin));
371 n->left = *nn;
372 n->n.func = n_and;
373 *nn = &n->n;
374 nn = &n->right;
375 }
376}
377
378static void p_expr(p_ctx *p, node **nn)
379{
380 node_bin *n;
381 for (;;) {
382 p_term(p, nn);
383 if (p->t != O_OR)
384 break;
385 p_next(p);
386 n = xmalloc(sizeof(node_bin));
387 n->left = *nn;
388 n->n.func = n_or;
389 *nn = &n->n;
390 nn = &n->right;
391 }
392}
393
394/* --- @p_argv@ --- *
395 *
396 * Arguments: @int argc@ = number of command-line arguments
397 * @const char *const argv[]@ = vectoor of arguments
398 *
399 * Returns: A compiled node, parsed from the arguments.
400 *
401 * Use: Does the donkey-work of parsing a command-line.
402 */
403
404static node *p_argv(int argc, const char *const argv[])
405{
406 p_ctx p;
407 node *n;
408
409 av = argv;
410 ac = argc;
411 ai = 1;
412 p_next(&p);
2668675c 413 if (p.t == O_EOF) {
414 usage(stderr);
415 pquis(stderr, "(Run `$ --help' for more detail.)\n");
416 exit(EXIT_FAILURE);
417 }
6e403221 418 p_expr(&p, &n);
419 if (p.t != O_EOF) {
420 die("syntax error near `%s': rubbish at end of line (too many `)'s?)",
421 *p.a);
422 }
423 return (n);
424}
425
426/*----- Main code ---------------------------------------------------------*/
427
428/* --- @main@ --- *
429 *
430 * Arguments: @int argc@ = number of command-line arguments
431 * @char *argv[]@ = vector of argument words
432 *
433 * Returns: Zero on success, nonzero on failure.
434 *
435 * Use: Picks entries from a word list which match particular
436 * expressions. This might be of assistance to word-game types.
437 */
438
439int main(int argc, char *argv[])
440{
441 node *n;
442 FILE *fp;
443 dstr d = DSTR_INIT;
444 char *p, *q, *l;
445
446 ego(argv[0]);
447 n = p_argv(argc, (const char *const *)argv);
448
449 if ((fp = fopen(file, "r")) == 0)
450 die("error opening `%s': %s", file, strerror(errno));
451 for (;;) {
452 dstr_reset(&d);
453 if (dstr_putline(&d, fp) < 0)
454 break;
455 l = d.buf + d.len;
456 for (p = q = d.buf; p < l; p++) {
457 if (!isalnum((unsigned char)*p))
458 continue;
459 *q++ = tolower((unsigned char)*p);
460 }
461 *q = 0;
462 d.len = q - d.buf;
463 if (n->func(n, d.buf, d.len)) {
464 fwrite(d.buf, 1, d.len, stdout);
465 fputc('\n', stdout);
466 }
467 }
468 if (!feof(fp))
469 die("error reading `%s': %s", file, strerror(errno));
470 fclose(fp);
471 return (0);
472}
473
474/*----- That's all, folks -------------------------------------------------*/