3 * $Id: anag.c,v 1.2 2001/02/07 09:09:11 mdw Exp $
7 * (c) 2001 Mark Wooding
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Anag: a simple wordgame helper.
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.
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.
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.
29 /*----- Revision history --------------------------------------------------*
32 * Revision 1.2 2001/02/07 09:09:11 mdw
33 * Fix spurious error when `-file' is used.
35 * Revision 1.1 2001/02/04 17:14:42 mdw
40 /*----- Header files ------------------------------------------------------*/
44 /*----- Static variables --------------------------------------------------*/
46 static const char *file
= DICTIONARY
;
48 /*----- Help text functions -----------------------------------------------*/
50 static void usage(FILE *fp
)
52 pquis(fp
, "Usage: $ [-f file] expression\n");
55 static void version(FILE *fp
)
57 pquis(fp
, "$, version " VERSION
"\n");
60 static void help(FILE *fp
)
66 Searches a wordlist, printing all of the words which match an expression.\n\
67 The basic tests in the expression are:\n\
69 -anagram WORD matches a full-length anagram\n\
70 -subgram WORD matches words which only use letters in WORD\n\
71 -wildcard PATTERN matches with wildcards `*' and `?'\n\
72 -trackword WORD matches words which can be found in a trackword\n\
74 These simple tests can be combined using the operators `-a', `-o' and `-n'\n\
75 (for `and', `or' and `not'; they may also be written `&', `|' and `!' if\n\
76 you like), and grouped using parentheses `(' and `)'.\n\
80 /*----- The options parser ------------------------------------------------*/
82 /* --- Options table structure --- */
92 O_HELP
, O_VERSION
, O_USAGE
,
94 O_AND
, O_OR
, O_NOT
, O_LPAREN
, O_RPAREN
,
95 O_ANAG
, O_SUBG
, O_WILD
, O_TRACK
,
101 static const struct opt opttab
[] = {
103 /* --- Options -- don't form part of the language --- */
105 { "help", 0, OF_SHORT
, O_HELP
},
106 { "version", 0, OF_SHORT
, O_VERSION
},
107 { "usage", 0, OF_SHORT
, O_USAGE
},
108 { "file", 1, OF_SHORT
, O_FILE
},
110 /* --- Operators -- provide the basic structure of the language --- *
112 * These are also given magical names by the parser.
115 { "and", 0, OF_SHORT
, O_AND
},
116 { "or", 0, OF_SHORT
, O_OR
},
117 { "not", 0, OF_SHORT
, O_NOT
},
119 /* --- Actual matching oeprations -- do something useful --- */
121 { "anagram", 1, 0, O_ANAG
},
122 { "subgram", 1, 0, O_SUBG
},
123 { "wildcard", 1, 0, O_WILD
},
124 { "trackword", 1, 0, O_TRACK
},
126 /* --- End marker --- */
132 static const char *const *av
;
135 /* --- @nextopt@ --- *
137 * Arguments: @const char ***arg@ = where to store the arg pointer
139 * Returns: The tag of the next option.
141 * Use: Scans the next option off the command line. If the option
142 * doesn't form part of the language, it's processed internally,
143 * and you'll never see it from here. On exit, the @arg@
144 * pointer is set to contain the address of the option scanned,
145 * followed by its arguments if any. You're expected to know
146 * how many arguments there are for your option.
149 static unsigned nextopt(const char *const **arg
)
152 const struct opt
*o
, *oo
;
156 /* --- Pick the next option off the front --- */
163 /* --- Cope with various forms of magic --- */
166 if (!p
[1]) switch (*p
) {
167 case '&': return (O_AND
);
168 case '|': return (O_OR
);
169 case '!': return (O_NOT
);
170 case '(': return (O_LPAREN
);
171 case ')': return (O_RPAREN
);
176 /* --- Now cope with other sorts of weirdies --- *
178 * By the end of this, a leading `-' or `--' will have been stripped.
188 die("syntax error near `--': rubbish at end of line");
192 /* --- Now look the word up in my table --- */
196 for (o
= opttab
; o
->name
; o
++) {
197 if (strncmp(p
, o
->name
, sz
) == 0) {
198 if (strlen(o
->name
) == sz
|| ((o
->f
& OF_SHORT
) && sz
== 1)) {
203 die("ambiguous option name `-%s' (could match `-%s' or `-%s')",
204 p
, oo
->name
, o
->name
);
210 die("unrecognized option name `-%s'", p
);
212 /* --- Sort out the arguments --- */
214 if (ai
+ oo
->nargs
> ac
)
215 die("too few arguments for `-%s' (need %u)", oo
->name
, oo
->nargs
);
218 /* --- Now process the option --- */
238 die("syntax error near `%s': unknown token type", av
[ai
- 1]);
242 /*----- Node types for operators ------------------------------------------*/
244 /* --- Node structures --- */
246 typedef struct node_bin
{
252 typedef struct node_un
{
257 /* --- Node functions --- */
259 static int n_or(node
*nn
, const char *p
, size_t sz
)
261 node_bin
*n
= (node_bin
*)nn
;
262 return (n
->left
->func(n
->left
, p
, sz
) || n
->right
->func(n
->right
, p
, sz
));
265 static int n_and(node
*nn
, const char *p
, size_t sz
)
267 node_bin
*n
= (node_bin
*)nn
;
268 return (n
->left
->func(n
->left
, p
, sz
) && n
->right
->func(n
->right
, p
, sz
));
271 static int n_not(node
*nn
, const char *p
, size_t sz
)
273 node_un
*n
= (node_un
*)nn
;
274 return (!n
->arg
->func(n
->arg
, p
, sz
));
277 /*----- Parser for the expression syntax ----------------------------------*/
279 /* --- A parser context --- */
281 typedef struct p_ctx
{
283 const char *const *a
;
286 /* --- Parser structure --- *
288 * This is a simple recursive descent parser. The context retains
289 * information about the current token. Each function is passed the address
290 * of a node pointer to fill in. This simplifies the binary operator code
291 * somewhat, relative to returning pointers to node trees.
294 static void p_expr(p_ctx
*p
, node
**/
*nn*/
);
296 static void p_next(p_ctx
*p
)
298 static const char *const eof
[] = { "<end>", 0 };
299 p
->t
= nextopt(&p
->a
);
304 static void p_factor(p_ctx
*p
, node
**nn
)
307 if (p
->t
== O_LPAREN
) {
310 if (p
->t
!= O_RPAREN
)
311 die("syntax error near `%s': missing `('", *p
->a
);
313 } else if (p
->t
== O_NOT
) {
314 n
= xmalloc(sizeof(node_un
));
318 p_factor(p
, &n
->arg
);
321 case O_ANAG
: *nn
= anagram(p
->a
+ 1); break;
322 case O_SUBG
: *nn
= subgram(p
->a
+ 1); break;
323 case O_WILD
: *nn
= wildcard(p
->a
+ 1); break;
324 case O_TRACK
: *nn
= trackword(p
->a
+ 1); break;
325 default: die("syntax error near `%s': unexpected token", *p
->a
);
331 static void p_term(p_ctx
*p
, node
**nn
)
347 n
= xmalloc(sizeof(node_bin
));
355 static void p_expr(p_ctx
*p
, node
**nn
)
363 n
= xmalloc(sizeof(node_bin
));
371 /* --- @p_argv@ --- *
373 * Arguments: @int argc@ = number of command-line arguments
374 * @const char *const argv[]@ = vectoor of arguments
376 * Returns: A compiled node, parsed from the arguments.
378 * Use: Does the donkey-work of parsing a command-line.
381 static node
*p_argv(int argc
, const char *const argv
[])
392 die("syntax error near `%s': rubbish at end of line (too many `)'s?)",
398 /*----- Main code ---------------------------------------------------------*/
402 * Arguments: @int argc@ = number of command-line arguments
403 * @char *argv[]@ = vector of argument words
405 * Returns: Zero on success, nonzero on failure.
407 * Use: Picks entries from a word list which match particular
408 * expressions. This might be of assistance to word-game types.
411 int main(int argc
, char *argv
[])
419 n
= p_argv(argc
, (const char *const *)argv
);
421 if ((fp
= fopen(file
, "r")) == 0)
422 die("error opening `%s': %s", file
, strerror(errno
));
425 if (dstr_putline(&d
, fp
) < 0)
428 for (p
= q
= d
.buf
; p
< l
; p
++) {
429 if (!isalnum((unsigned char)*p
))
431 *q
++ = tolower((unsigned char)*p
);
435 if (n
->func(n
, d
.buf
, d
.len
)) {
436 fwrite(d
.buf
, 1, d
.len
, stdout
);
441 die("error reading `%s': %s", file
, strerror(errno
));
446 /*----- That's all, folks -------------------------------------------------*/