contrib/gperf/src/iterator.cc

   1 /* Provides an Iterator for keyword characters.
   2    Copyright (C) 1989-1998, 2000 Free Software Foundation, Inc.
   3    written by Douglas C. Schmidt (schmidt@ics.uci.edu)
   4
   5 This file is part of GNU GPERF.
   6
   7 GNU GPERF is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 1, or (at your option)
  10 any later version.
  11
  12 GNU GPERF is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU GPERF; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111, USA.  */
  20
  21 #include "iterator.h"
  22
  23 #include <ctype.h>
  24 #include "trace.h"
  25
  26 /* Constructor for Iterator. */
  27
  28 Iterator::Iterator (const char *s, int lo, int hi, int word_end, int bad_val, int key_end)
  29 {
  30   T (Trace t ("Iterator::Iterator");)
  31   end         = key_end;
  32   error_value = bad_val;
  33   end_word    = word_end;
  34   str         = s;
  35   hi_bound    = hi;
  36   lo_bound    = lo;
  37 }
  38
  39 /* Provide an Iterator, returning the ``next'' value from
  40    the list of valid values given in the constructor. */
  41
  42 int
  43 Iterator::operator() (void)
  44 {
  45   T (Trace t ("Iterator::operator()");)
  46 /* Variables to record the Iterator's status when handling ranges, e.g., 3-12. */
  47
  48   static int size;
  49   static int curr_value;
  50   static int upper_bound;
  51
  52   if (size)
  53     {
  54       if (++curr_value >= upper_bound)
  55         size = 0;
  56       return curr_value;
  57     }
  58   else
  59     {
  60       while (*str)
  61         switch (*str)
  62           {
  63           default: return error_value;
  64           case ',': str++; break;
  65           case '$': str++; return end_word;
  66           case '0': case '1': case '2': case '3': case '4':
  67           case '5': case '6': case '7': case '8': case '9':
  68             for (curr_value = 0; isdigit ((unsigned char)(*str)); str++)
  69               curr_value = curr_value * 10 + (*str - '0');
  70
  71             if (*str == '-')
  72               {
  73
  74                 for (size = 1, upper_bound = 0;
  75                      isdigit ((unsigned char)(*++str));
  76                      upper_bound = upper_bound * 10 + (*str - '0'));
  77
  78                 if (upper_bound <= curr_value || upper_bound > hi_bound)
  79                   return error_value;
  80               }
  81             return curr_value >= lo_bound && curr_value <= hi_bound
  82               ? curr_value : error_value;
  83           }
  84
  85       return end;
  86     }
  87 }