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

   1 /* -*-c-*-
   2  *
   3  * Matches Perl-compatible 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 <pcre.h>
  32
  33 /*----- Data structures ---------------------------------------------------*/
  34
  35 typedef struct node_pcre {
  36   node n;
  37   const char *s;
  38   pcre *rx;
  39   pcre_extra *rx_study;
  40   int *ovec;
  41   int ovecsz;
  42 } node_pcre;
  43
  44 /*----- Main code ---------------------------------------------------------*/
  45
  46 /* --- Node matcher --- */
  47
  48 static int n_pcre(node *nn, const char *p, size_t sz)
  49 {
  50   node_pcre *n = (node_pcre *)nn;
  51   int e;
  52
  53   e = pcre_exec(n->rx, n->rx_study, p, sz, 0, 0, n->ovec, n->ovecsz);
  54   if (e >= 0) return (1);
  55   if (e == PCRE_ERROR_NOMATCH) return (0);
  56   die("unexpected PCRE error code %d", e);
  57 }
  58
  59 /* --- Node creation --- */
  60
  61 node *pcrenode(const char *const *av)
  62 {
  63   node_pcre *n = xmalloc(sizeof(*n));
  64   const char *e;
  65   int eo;
  66   int c;
  67
  68   n->n.func = n_pcre;
  69
  70   n->rx = pcre_compile(av[0], PCRE_CASELESS, &e, &eo, 0);
  71   if (!n->rx) die("bad regular expression `%s': %s", av[0], e);
  72   n->rx_study = pcre_study(n->rx, 0, &e);
  73   if (e) die("error studying pattern `%s': %s", av[0], e);
  74   pcre_fullinfo(n->rx, n->rx_study, PCRE_INFO_CAPTURECOUNT, &c);
  75   n->ovecsz = 2*c;
  76   n->ovec = xmalloc(n->ovecsz*sizeof(*n->ovec));
  77
  78   return (&n->n);
  79 }
  80
  81 /*----- That's all, folks -------------------------------------------------*/