mdw@git.distorted.org.uk Git - anag/blob - regexp.c

   1 /* -*-c-*-
   2  *
   3  * Matches regular expressions
   4  *
   5  * (c) 2002 Mark Wooding
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Anag: a simple wordgame helper.
  11  *
  12  * Anag is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * Anag is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with Anag; if not, write to the Free Software Foundation,
  24  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25  */
  26
  27 /*----- Header files ------------------------------------------------------*/
  28
  29 #include "anag.h"
  30
  31 #include <regex.h>
  32
  33 /*----- Data structures ---------------------------------------------------*/
  34
  35 typedef struct node_regexp {
  36   node n;
  37   const char *s;
  38   regex_t rx;
  39 } node_regexp;
  40
  41 /*----- Main code ---------------------------------------------------------*/
  42
  43 /* --- Node matcher --- */
  44
  45 static int n_regexp(node *nn, const char *p, size_t sz)
  46 {
  47   node_regexp *n = (node_regexp *)nn;
  48   char buf[256];
  49   int e;
  50
  51   switch (e = regexec(&n->rx, p, 0, 0, 0)) {
  52     case 0: return 1;
  53     case REG_NOMATCH: return 0;
  54     default:
  55       regerror(e, &n->rx, buf, sizeof(buf));
  56       die("error matching regexp `%s' against `%s': %s",
  57           n->s, p, buf);
  58       break;
  59   }
  60   return (0);
  61 }
  62
  63 /* --- Node creation --- */
  64
  65 node *regexp(const char *const *av)
  66 {
  67   node_regexp *n = xmalloc(sizeof(*n));
  68   char buf[256];
  69   int e;
  70
  71   n->n.func = n_regexp;
  72   if ((e = regcomp(&n->rx, av[0],
  73                    REG_EXTENDED | REG_ICASE | REG_NOSUB)) != 0) {
  74     regerror(e, &n->rx, buf, sizeof(buf));
  75     die("bad regular expression `%s': %s", av[0], buf);
  76   }
  77   return (&n->n);
  78 }
  79
  80 /*----- That's all, folks -------------------------------------------------*/