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