pcre.c, etc.: Support the PCRE2 library.

[anag] / pcre.c

/* -*-c-*-
 *
 * Matches Perl-compatible regular expressions
 *
 * (c) 2002 Mark Wooding
 */

/*----- Licensing notice --------------------------------------------------*
 *
 * This file is part of Anag: a simple wordgame helper.
 *
 * Anag is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Anag is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Anag; if not, write to the Free Software Foundation,
 * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

/*----- Header files ------------------------------------------------------*/

#include "anag.h"

#ifdef HAVE_PCRE2
#  define PCRE2_CODE_UNIT_WIDTH 8
#  include <pcre2.h>
#endif

#ifdef HAVE_PCRE
#  include <pcre.h>
#endif

/*----- Data structures ---------------------------------------------------*/

typedef struct node_pcre {
  node n;
  const char *s;
#ifdef HAVE_PCRE2
  pcre2_code *rx;
  pcre2_match_data *m;
#endif
#ifdef HAVE_PCRE
  pcre *rx;
  pcre_extra *rx_study;
  int *ovec;
  int ovecsz;
#endif
} node_pcre;

/*----- Main code ---------------------------------------------------------*/

/* --- Node matcher --- */

static int n_pcre(node *nn, const char *p, size_t sz)
{
  node_pcre *n = (node_pcre *)nn;
#ifdef HAVE_PCRE2
  char buf[128];
  int rc;
#endif
#ifdef HAVE_PCRE
  int e;
#endif

#ifdef HAVE_PCRE2
  rc = pcre2_match(n->rx, (PCRE2_SPTR)p, sz, 0, 0, n->m, 0);
  if (rc >= 0) return (1);
  else switch (rc) {
    case PCRE2_ERROR_NOMATCH: return (0);
    default:
      rc = pcre2_get_error_message(rc, (PCRE2_UCHAR *)buf, sizeof(buf));
      assert(!rc); die("pcre2 matching failed': %s", buf);
  }
#endif
#ifdef HAVE_PCRE
  e = pcre_exec(n->rx, n->rx_study, p, sz, 0, 0, n->ovec, n->ovecsz);
  if (e >= 0) return (1);
  if (e == PCRE_ERROR_NOMATCH) return (0);
  die("unexpected PCRE error code %d", e);
#endif
}

/* --- Node creation --- */

node *pcrenode(const char *const *av)
{
  node_pcre *n = xmalloc(sizeof(*n));
#ifdef HAVE_PCRE2
  char buf[128];
  int err;
  PCRE2_SIZE eo;
  uint32_t c;
#endif
#ifdef HAVE_PCRE
  const char *e;
  int eo;
  int c;
#endif

  n->n.func = n_pcre;

#ifdef HAVE_PCRE2
  n->rx = pcre2_compile((PCRE2_SPTR)av[0], strlen(av[0]), PCRE2_CASELESS,
			&err, &eo, 0);
  if (!n->rx) {
    err = pcre2_get_error_message(err, (PCRE2_UCHAR *)buf, sizeof(buf));
    assert(!err); die("bad regular expression `%s': %s", av[0], buf);
  }
  err = pcre2_pattern_info(n->rx, PCRE2_INFO_BACKREFMAX, &c);
  assert(!err);
  n->m = pcre2_match_data_create_from_pattern(n->rx, 0);
  if (!n->m) {
    err = pcre2_get_error_message(err, (PCRE2_UCHAR *)buf, sizeof(buf));
    assert(!err); die("failed to allocate match data: %s", buf);
  }
  pcre2_jit_compile(n->rx, PCRE2_JIT_COMPLETE);
#endif
#ifdef HAVE_PCRE
  n->rx = pcre_compile(av[0], PCRE_CASELESS, &e, &eo, 0);
  if (!n->rx) die("bad regular expression `%s': %s", av[0], e);
  n->rx_study = pcre_study(n->rx, 0, &e);
  if (e) die("error studying pattern `%s': %s", av[0], e);
  pcre_fullinfo(n->rx, n->rx_study, PCRE_INFO_CAPTURECOUNT, &c);
  n->ovecsz = 2*c;
  n->ovec = xmalloc(n->ovecsz*sizeof(*n->ovec));
#endif

  return (&n->n);
}

/*----- That's all, folks -------------------------------------------------*/