src/libs/libgroff/nametoindex.cpp

   1 // -*- C++ -*-
   2 /* Copyright (C) 1989, 1990, 1991, 1992, 2000, 2001, 2002, 2003, 2004
   3    Free Software Foundation, Inc.
   4      Written by James Clark (jjc@jclark.com)
   5
   6 This file is part of groff.
   7
   8 groff is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 2, or (at your option) any later
  11 version.
  12
  13 groff is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License along
  19 with groff; see the file COPYING.  If not, write to the Free Software
  20 Foundation, 51 Franklin St - Fifth Floor, Boston, MA 02110-1301, USA. */
  21
  22 #include "lib.h"
  23
  24 #include <ctype.h>
  25 #include <assert.h>
  26 #include <stdlib.h>
  27 #include "errarg.h"
  28 #include "error.h"
  29 #include "font.h"
  30 #include "ptable.h"
  31
  32 declare_ptable(int)
  33 implement_ptable(int)
  34
  35 class character_indexer {
  36 public:
  37   character_indexer();
  38   ~character_indexer();
  39   int ascii_char_index(unsigned char);
  40   int named_char_index(const char *);
  41   int numbered_char_index(int);
  42 private:
  43   enum { NSMALL = 256 };
  44   int next_index;
  45   int ascii_index[256];
  46   int small_number_index[NSMALL];
  47   PTABLE(int) table;
  48 };
  49
  50 character_indexer::character_indexer()
  51 : next_index(0)
  52 {
  53   int i;
  54   for (i = 0; i < 256; i++)
  55     ascii_index[i] = -1;
  56   for (i = 0; i < NSMALL; i++)
  57     small_number_index[i] = -1;
  58 }
  59
  60 character_indexer::~character_indexer()
  61 {
  62 }
  63
  64 int character_indexer::ascii_char_index(unsigned char c)
  65 {
  66   if (ascii_index[c] < 0)
  67     ascii_index[c] = next_index++;
  68   return ascii_index[c];
  69 }
  70
  71 int character_indexer::numbered_char_index(int n)
  72 {
  73   if (n >= 0 && n < NSMALL) {
  74     if (small_number_index[n] < 0)
  75       small_number_index[n] = next_index++;
  76     return small_number_index[n];
  77   }
  78   // Not the most efficient possible implementation.
  79   char buf[INT_DIGITS + 3];
  80   buf[0] = ' ';
  81   strcpy(buf + 1, i_to_a(n));
  82   return named_char_index(buf);
  83 }
  84
  85 int character_indexer::named_char_index(const char *s)
  86 {
  87   int *np = table.lookup(s);
  88   if (!np) {
  89     np = new int[1];
  90     *np = next_index++;
  91     table.define(s, np);
  92   }
  93   return *np;
  94 }
  95
  96 static character_indexer indexer;
  97
  98 int font::number_to_index(int n)
  99 {
 100   return indexer.numbered_char_index(n);
 101 }
 102
 103 int font::name_to_index(const char *s)
 104 {
 105   assert(s != 0 && s[0] != '\0' && s[0] != ' ');
 106   if (s[1] == '\0')
 107     return indexer.ascii_char_index(s[0]);
 108   /* char128 and \200 are synonyms */
 109   if (s[0] == 'c' && s[1] == 'h' && s[2] == 'a' && s[3] == 'r') {
 110     char *val;
 111     long n = strtol(s + 4, &val, 10);
 112     if (val != s + 4 && *val == '\0' && n >= 0 && n < 256)
 113       return indexer.ascii_char_index((unsigned char)n);
 114   }
 115   return indexer.named_char_index(s);
 116 }
 117