chiark / gitweb /
Various fixes.
[anag] / anag.c
CommitLineData
6e403221 1/* -*-c-*-
2 *
d9af4a2b 3 * $Id: anag.c,v 1.7 2003/11/29 23:38:37 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
29/*----- Revision history --------------------------------------------------*
30 *
31 * $Log: anag.c,v $
d9af4a2b 32 * Revision 1.7 2003/11/29 23:38:37 mdw
33 * Debianization.
34 *
fe9969ff 35 * Revision 1.6 2003/09/15 02:48:54 mdw
36 * Monoalphabetic match filter.
37 *
a10122de 38 * Revision 1.5 2002/08/11 12:58:09 mdw
39 * Added support for regular expression matching, if supported by the C
40 * library.
41 *
1d2d1062 42 * Revision 1.4 2001/02/19 19:18:50 mdw
43 * Minor big fixes to parser.
44 *
2668675c 45 * Revision 1.3 2001/02/16 21:45:19 mdw
46 * Be more helpful. Improve full help message. Special-case error for
47 * empty command strings.
48 *
60dffc01 49 * Revision 1.2 2001/02/07 09:09:11 mdw
50 * Fix spurious error when `-file' is used.
51 *
6e403221 52 * Revision 1.1 2001/02/04 17:14:42 mdw
53 * Initial checkin
54 *
55 */
56
57/*----- Header files ------------------------------------------------------*/
58
59#include "anag.h"
60
61/*----- Static variables --------------------------------------------------*/
62
63static const char *file = DICTIONARY;
64
65/*----- Help text functions -----------------------------------------------*/
66
67static void usage(FILE *fp)
68{
69 pquis(fp, "Usage: $ [-f file] expression\n");
70}
71
72static void version(FILE *fp)
73{
74 pquis(fp, "$, version " VERSION "\n");
75}
76
77static void help(FILE *fp)
78{
79 version(fp);
80 fputc('\n', fp);
81 usage(fp);
82 fputs("\n\
83Searches a wordlist, printing all of the words which match an expression.\n\
2668675c 84\n\
85Options supported are:\n\
86\n\
87-h, --help display this help text\n\
88-v, --version display the program's version number\n\
89-u, --usage display a very brief usage message\n\
90-f, --file FILE read wordlist from FILE, not `" DICTIONARY "'\n\
91\n\
6e403221 92The basic tests in the expression are:\n\
93\n\
94-anagram WORD matches a full-length anagram\n\
95-subgram WORD matches words which only use letters in WORD\n\
96-wildcard PATTERN matches with wildcards `*' and `?'\n\
97-trackword WORD matches words which can be found in a trackword\n\
fe9969ff 98-mono PATTERN matches words isomorphic to the given PATTERN\n\
a10122de 99"
100#ifdef HAVE_REGCOMP
101"\
102-regexp REGEXP matches with an (extended) regular expression\n\
103"
104#endif
d9af4a2b 105#ifdef HAVE_PCRE
106"\
107-pcre REGEXP matches with a Perl-like regular expression\n\
108"
109#endif
a10122de 110"\
6e403221 111\n\
112These simple tests can be combined using the operators `-a', `-o' and `-n'\n\
113(for `and', `or' and `not'; they may also be written `&', `|' and `!' if\n\
114you like), and grouped using parentheses `(' and `)'.\n\
d9af4a2b 115", fp); /*"*/
6e403221 116}
117
118/*----- The options parser ------------------------------------------------*/
119
120/* --- Options table structure --- */
121
122struct opt {
123 const char *name;
124 unsigned nargs;
125 unsigned f;
126 unsigned tag;
127};
128
129enum {
130 O_HELP, O_VERSION, O_USAGE,
131 O_FILE,
132 O_AND, O_OR, O_NOT, O_LPAREN, O_RPAREN,
d9af4a2b 133 O_ANAG, O_SUBG, O_WILD, O_TRACK, O_REGEXP, O_PCRE, O_MONO,
6e403221 134 O_EOF
135};
136
137#define OF_SHORT 1u
138
139static const struct opt opttab[] = {
140
141 /* --- Options -- don't form part of the language --- */
142
143 { "help", 0, OF_SHORT, O_HELP },
144 { "version", 0, OF_SHORT, O_VERSION },
145 { "usage", 0, OF_SHORT, O_USAGE },
146 { "file", 1, OF_SHORT, O_FILE },
147
148 /* --- Operators -- provide the basic structure of the language --- *
149 *
150 * These are also given magical names by the parser.
151 */
152
153 { "and", 0, OF_SHORT, O_AND },
154 { "or", 0, OF_SHORT, O_OR },
155 { "not", 0, OF_SHORT, O_NOT },
156
157 /* --- Actual matching oeprations -- do something useful --- */
158
159 { "anagram", 1, 0, O_ANAG },
160 { "subgram", 1, 0, O_SUBG },
161 { "wildcard", 1, 0, O_WILD },
162 { "trackword", 1, 0, O_TRACK },
fe9969ff 163 { "mono", 1, 0, O_MONO },
a10122de 164#ifdef HAVE_REGCOMP
165 { "regexp", 1, 0, O_REGEXP },
166#endif
d9af4a2b 167#ifdef HAVE_PCRE
168 { "pcre", 1, 0, O_PCRE },
169#endif
6e403221 170
171 /* --- End marker --- */
172
173 { 0, 0, 0, 0 }
174};
175
176static int ac;
177static const char *const *av;
178static int ai;
179
180/* --- @nextopt@ --- *
181 *
182 * Arguments: @const char ***arg@ = where to store the arg pointer
183 *
184 * Returns: The tag of the next option.
185 *
186 * Use: Scans the next option off the command line. If the option
187 * doesn't form part of the language, it's processed internally,
188 * and you'll never see it from here. On exit, the @arg@
189 * pointer is set to contain the address of the option scanned,
190 * followed by its arguments if any. You're expected to know
191 * how many arguments there are for your option.
192 */
193
194static unsigned nextopt(const char *const **arg)
195{
196 for (;;) {
197 const struct opt *o, *oo;
198 size_t sz;
199 const char *p;
200
201 /* --- Pick the next option off the front --- */
202
203 *arg = av + ai;
204 if (ai >= ac)
205 return (O_EOF);
206 p = av[ai++];
207
208 /* --- Cope with various forms of magic --- */
209
210 if (p[0] != '-') {
211 if (!p[1]) switch (*p) {
212 case '&': return (O_AND);
213 case '|': return (O_OR);
214 case '!': return (O_NOT);
215 case '(': return (O_LPAREN);
216 case ')': return (O_RPAREN);
217 }
218 goto bad;
219 }
220
221 /* --- Now cope with other sorts of weirdies --- *
222 *
223 * By the end of this, a leading `-' or `--' will have been stripped.
224 */
225
226 p++;
227 if (!*p)
228 goto bad;
229 if (*p == '-')
230 p++;
231 if (!*p) {
232 if (ai < ac)
233 die("syntax error near `--': rubbish at end of line");
234 return (O_EOF);
235 }
236
237 /* --- Now look the word up in my table --- */
238
239 sz = strlen(p);
240 oo = 0;
241 for (o = opttab; o->name; o++) {
242 if (strncmp(p, o->name, sz) == 0) {
243 if (strlen(o->name) == sz || ((o->f & OF_SHORT) && sz == 1)) {
244 oo = o;
245 break;
246 }
247 if (oo) {
248 die("ambiguous option name `-%s' (could match `-%s' or `-%s')",
249 p, oo->name, o->name);
250 }
251 oo = o;
252 }
253 }
254 if (!oo)
255 die("unrecognized option name `-%s'", p);
256
257 /* --- Sort out the arguments --- */
258
259 if (ai + oo->nargs > ac)
260 die("too few arguments for `-%s' (need %u)", oo->name, oo->nargs);
261 ai += oo->nargs;
262
263 /* --- Now process the option --- */
264
265 switch (oo->tag) {
266 case O_HELP:
267 help(stdout);
268 exit(0);
269 case O_VERSION:
270 version(stdout);
271 exit(0);
272 case O_USAGE:
273 usage(stdout);
274 exit(0);
275 case O_FILE:
276 file = (*arg)[1];
277 break;
278 default:
279 return (oo->tag);
280 }
60dffc01 281 continue;
6e403221 282 bad:
283 die("syntax error near `%s': unknown token type", av[ai - 1]);
284 }
285}
286
287/*----- Node types for operators ------------------------------------------*/
288
289/* --- Node structures --- */
290
291typedef struct node_bin {
292 node n;
293 node *left;
294 node *right;
295} node_bin;
296
297typedef struct node_un {
298 node n;
299 node *arg;
300} node_un;
301
302/* --- Node functions --- */
303
304static int n_or(node *nn, const char *p, size_t sz)
305{
306 node_bin *n = (node_bin *)nn;
307 return (n->left->func(n->left, p, sz) || n->right->func(n->right, p, sz));
308}
309
310static int n_and(node *nn, const char *p, size_t sz)
311{
312 node_bin *n = (node_bin *)nn;
313 return (n->left->func(n->left, p, sz) && n->right->func(n->right, p, sz));
314}
315
316static int n_not(node *nn, const char *p, size_t sz)
317{
318 node_un *n = (node_un *)nn;
319 return (!n->arg->func(n->arg, p, sz));
320}
321
322/*----- Parser for the expression syntax ----------------------------------*/
323
324/* --- A parser context --- */
325
326typedef struct p_ctx {
327 unsigned t;
328 const char *const *a;
329} p_ctx;
330
331/* --- Parser structure --- *
332 *
333 * This is a simple recursive descent parser. The context retains
334 * information about the current token. Each function is passed the address
335 * of a node pointer to fill in. This simplifies the binary operator code
336 * somewhat, relative to returning pointers to node trees.
337 */
338
339static void p_expr(p_ctx *p, node **/*nn*/);
340
341static void p_next(p_ctx *p)
342{
343 static const char *const eof[] = { "<end>", 0 };
344 p->t = nextopt(&p->a);
345 if (p->t == O_EOF)
346 p->a = eof;
347}
348
349static void p_factor(p_ctx *p, node **nn)
350{
351 node_un *n;
352 if (p->t == O_LPAREN) {
353 p_next(p);
354 p_expr(p, nn);
355 if (p->t != O_RPAREN)
1d2d1062 356 die("syntax error near `%s': missing `)'", *p->a);
6e403221 357 p_next(p);
358 } else if (p->t == O_NOT) {
359 n = xmalloc(sizeof(node_un));
360 n->n.func = n_not;
361 *nn = &n->n;
362 p_next(p);
363 p_factor(p, &n->arg);
364 } else {
365 switch (p->t) {
366 case O_ANAG: *nn = anagram(p->a + 1); break;
367 case O_SUBG: *nn = subgram(p->a + 1); break;
368 case O_WILD: *nn = wildcard(p->a + 1); break;
369 case O_TRACK: *nn = trackword(p->a + 1); break;
a10122de 370#ifdef HAVE_REGCOMP
371 case O_REGEXP: *nn = regexp(p->a + 1); break;
372#endif
d9af4a2b 373#ifdef HAVE_PCRE
374 case O_PCRE: *nn = pcrenode(p->a + 1); break;
375#endif
fe9969ff 376 case O_MONO: *nn = mono(p->a + 1); break;
6e403221 377 default: die("syntax error near `%s': unexpected token", *p->a);
378 }
379 p_next(p);
380 }
381}
382
383static void p_term(p_ctx *p, node **nn)
384{
385 node_bin *n;
386 for (;;) {
387 p_factor(p, nn);
388 switch (p->t) {
389 case O_AND:
390 p_next(p);
391 default:
392 break;
6e403221 393 case O_RPAREN:
394 case O_OR:
395 case O_EOF:
396 return;
397 }
398 n = xmalloc(sizeof(node_bin));
399 n->left = *nn;
400 n->n.func = n_and;
401 *nn = &n->n;
402 nn = &n->right;
403 }
404}
405
406static void p_expr(p_ctx *p, node **nn)
407{
408 node_bin *n;
409 for (;;) {
410 p_term(p, nn);
411 if (p->t != O_OR)
412 break;
413 p_next(p);
414 n = xmalloc(sizeof(node_bin));
415 n->left = *nn;
416 n->n.func = n_or;
417 *nn = &n->n;
418 nn = &n->right;
419 }
420}
421
422/* --- @p_argv@ --- *
423 *
424 * Arguments: @int argc@ = number of command-line arguments
425 * @const char *const argv[]@ = vectoor of arguments
426 *
427 * Returns: A compiled node, parsed from the arguments.
428 *
429 * Use: Does the donkey-work of parsing a command-line.
430 */
431
432static node *p_argv(int argc, const char *const argv[])
433{
434 p_ctx p;
435 node *n;
436
437 av = argv;
438 ac = argc;
439 ai = 1;
440 p_next(&p);
2668675c 441 if (p.t == O_EOF) {
442 usage(stderr);
443 pquis(stderr, "(Run `$ --help' for more detail.)\n");
444 exit(EXIT_FAILURE);
445 }
6e403221 446 p_expr(&p, &n);
447 if (p.t != O_EOF) {
448 die("syntax error near `%s': rubbish at end of line (too many `)'s?)",
449 *p.a);
450 }
451 return (n);
452}
453
454/*----- Main code ---------------------------------------------------------*/
455
456/* --- @main@ --- *
457 *
458 * Arguments: @int argc@ = number of command-line arguments
459 * @char *argv[]@ = vector of argument words
460 *
461 * Returns: Zero on success, nonzero on failure.
462 *
463 * Use: Picks entries from a word list which match particular
464 * expressions. This might be of assistance to word-game types.
465 */
466
467int main(int argc, char *argv[])
468{
469 node *n;
470 FILE *fp;
471 dstr d = DSTR_INIT;
472 char *p, *q, *l;
473
474 ego(argv[0]);
475 n = p_argv(argc, (const char *const *)argv);
476
477 if ((fp = fopen(file, "r")) == 0)
478 die("error opening `%s': %s", file, strerror(errno));
479 for (;;) {
480 dstr_reset(&d);
481 if (dstr_putline(&d, fp) < 0)
482 break;
483 l = d.buf + d.len;
484 for (p = q = d.buf; p < l; p++) {
485 if (!isalnum((unsigned char)*p))
486 continue;
487 *q++ = tolower((unsigned char)*p);
488 }
489 *q = 0;
490 d.len = q - d.buf;
491 if (n->func(n, d.buf, d.len)) {
492 fwrite(d.buf, 1, d.len, stdout);
493 fputc('\n', stdout);
494 }
495 }
496 if (!feof(fp))
497 die("error reading `%s': %s", file, strerror(errno));
498 fclose(fp);
499 return (0);
500}
501
502/*----- That's all, folks -------------------------------------------------*/