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 #ifdef HAVE_CONFIG_H
  30 #  include "config.h"
  31 #endif
  32
  33 #ifndef HAVE_REGCOMP
  34   extern int dummy;
  35 #else
  36
  37 #include "anag.h"
  38 #include <regex.h>
  39
  40 /*----- Data structures ---------------------------------------------------*/
  41
  42 typedef struct node_regexp {
  43   node n;
  44   const char *s;
  45   regex_t rx;
  46 } node_regexp;
  47
  48 /*----- Main code ---------------------------------------------------------*/
  49
  50 /* --- Node matcher --- */
  51
  52 static int n_regexp(node *nn, const char *p, size_t sz)
  53 {
  54   node_regexp *n = (node_regexp *)nn;
  55   int e;
  56
  57   switch (e = regexec(&n->rx, p, 0, 0, 0)) {
  58     case 0:
  59       return 1;
  60     case REG_NOMATCH:
  61       return 0;
  62     default: {
  63       char buf[256];
  64       regerror(e, &n->rx, buf, sizeof(buf));
  65       die("error matching regexp `%s' against `%s': %s",
  66           n->s, p, buf);
  67     } break;
  68   }
  69   return (0);
  70 }
  71
  72 /* --- Node creation --- */
  73
  74 node *regexp(const char *const *av)
  75 {
  76   node_regexp *n = xmalloc(sizeof(*n));
  77   int e;
  78   n->n.func = n_regexp;
  79   if ((e = regcomp(&n->rx, av[0],
  80                    REG_EXTENDED | REG_ICASE | REG_NOSUB)) != 0) {
  81     char buf[256];
  82     regerror(e, &n->rx, buf, sizeof(buf));
  83     die("bad regular expression `%s': %s", av[0], buf);
  84   }
  85   return (&n->n);
  86 }
  87
  88 /*----- That's all, folks -------------------------------------------------*/
  89
  90 #endif