rx/rxbasic.c

   1 /*      Copyright (C) 1995, 1996 Tom Lord
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU Library General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU Library General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Library General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, 59 Temple Place - Suite 330,
  16  * Boston, MA 02111-1307, USA.
  17  */
  18
  19
  20 \f
  21 #include "rxall.h"
  22 #include "rxbasic.h"
  23 #include "rxstr.h"
  24
  25
  26 \f
  27
  28 int rx_basic_unfaniverse_delay = RX_DEFAULT_NFA_DELAY;
  29 static struct rx_unfaniverse * rx_basic_uv = 0;
  30
  31 \f
  32
  33 static int
  34 init_basic_once ()
  35 {
  36   if (rx_basic_uv)
  37     return 0;
  38   rx_basic_uv = rx_make_unfaniverse (rx_basic_unfaniverse_delay);
  39   return (rx_basic_uv ? 0 : -1);
  40 }
  41
  42 \f
  43 #ifdef __STDC__
  44 struct rx_unfaniverse *
  45 rx_basic_unfaniverse (void)
  46 #else
  47 struct rx_unfaniverse *
  48 rx_basic_unfaniverse ()
  49 #endif
  50 {
  51   if (init_basic_once ())
  52     return 0;
  53   return rx_basic_uv;
  54 }
  55 \f
  56
  57 static char * silly_hack = 0;
  58
  59 #ifdef __STDC__
  60 struct rx_solutions *
  61 rx_basic_make_solutions (struct rx_registers * regs, struct rexp_node * expression, struct rexp_node ** subexps, int start, int end, struct rx_context_rules * rules, const unsigned char * str)
  62 #else
  63 struct rx_solutions *
  64 rx_basic_make_solutions (regs, expression, subexps, start, end, rules, str)
  65      struct rx_registers * regs;
  66      struct rexp_node * expression;
  67      struct rexp_node ** subexps;
  68      int start;
  69      int end;
  70      struct rx_context_rules * rules;
  71      const unsigned char * str;
  72 #endif
  73 {
  74   struct rx_str_closure * closure;
  75   if (init_basic_once ())
  76     return 0;                   /* bogus but rare */
  77   if (   expression
  78       && (expression->len >= 0)
  79       && (expression->len != (end - start)))
  80     return &rx_no_solutions;
  81   if (silly_hack)
  82     {
  83       closure = (struct rx_str_closure *)silly_hack;
  84       silly_hack = 0;
  85     }
  86   else
  87     closure = (struct rx_str_closure *)malloc (sizeof (*closure));
  88   if (!closure)
  89     return 0;
  90   closure->str = str;
  91   closure->len = end;
  92   closure->rules = *rules;
  93   return rx_make_solutions (regs, rx_basic_uv, expression, subexps, 256,
  94                             start, end, rx_str_vmfn, rx_str_contextfn,
  95                             (void *)closure);
  96 }
  97
  98
  99
 100 #ifdef __STDC__
 101 void
 102 rx_basic_free_solutions (struct rx_solutions * solns)
 103 #else
 104      void
 105      rx_basic_free_solutions (solns)
 106      struct rx_solutions * solns;
 107 #endif
 108 {
 109   if (solns == &rx_no_solutions)
 110     return;
 111
 112   if (!silly_hack)
 113     silly_hack = (char *)solns->closure;
 114   else
 115     free (solns->closure);
 116   solns->closure = 0;
 117   rx_free_solutions (solns);
 118 }