pdftops/NameToCharCode.cxx

   1 //========================================================================
   2 //
   3 // NameToCharCode.cc
   4 //
   5 // Copyright 2001-2003 Glyph & Cog, LLC
   6 //
   7 //========================================================================
   8
   9 #include <config.h>
  10
  11 #ifdef USE_GCC_PRAGMAS
  12 #pragma implementation
  13 #endif
  14
  15 #include <string.h>
  16 #include "gmem.h"
  17 #include "NameToCharCode.h"
  18
  19 //------------------------------------------------------------------------
  20
  21 struct NameToCharCodeEntry {
  22   char *name;
  23   CharCode c;
  24 };
  25
  26 //------------------------------------------------------------------------
  27
  28 NameToCharCode::NameToCharCode() {
  29   int i;
  30
  31   size = 31;
  32   len = 0;
  33   tab = (NameToCharCodeEntry *)gmallocn(size, sizeof(NameToCharCodeEntry));
  34   for (i = 0; i < size; ++i) {
  35     tab[i].name = NULL;
  36   }
  37 }
  38
  39 NameToCharCode::~NameToCharCode() {
  40   int i;
  41
  42   for (i = 0; i < size; ++i) {
  43     if (tab[i].name) {
  44       gfree(tab[i].name);
  45     }
  46   }
  47   gfree(tab);
  48 }
  49
  50 void NameToCharCode::add(char *name, CharCode c) {
  51   NameToCharCodeEntry *oldTab;
  52   int h, i, oldSize;
  53
  54   // expand the table if necessary
  55   if (len >= size / 2) {
  56     oldSize = size;
  57     oldTab = tab;
  58     size = 2*size + 1;
  59     tab = (NameToCharCodeEntry *)gmallocn(size, sizeof(NameToCharCodeEntry));
  60     for (h = 0; h < size; ++h) {
  61       tab[h].name = NULL;
  62     }
  63     for (i = 0; i < oldSize; ++i) {
  64       if (oldTab[i].name) {
  65         h = hash(oldTab[i].name);
  66         while (tab[h].name) {
  67           if (++h == size) {
  68             h = 0;
  69           }
  70         }
  71         tab[h] = oldTab[i];
  72       }
  73     }
  74     gfree(oldTab);
  75   }
  76
  77   // add the new name
  78   h = hash(name);
  79   while (tab[h].name && strcmp(tab[h].name, name)) {
  80     if (++h == size) {
  81       h = 0;
  82     }
  83   }
  84   if (!tab[h].name) {
  85     tab[h].name = copyString(name);
  86   }
  87   tab[h].c = c;
  88
  89   ++len;
  90 }
  91
  92 CharCode NameToCharCode::lookup(char *name) {
  93   int h;
  94
  95   h = hash(name);
  96   while (tab[h].name) {
  97     if (!strcmp(tab[h].name, name)) {
  98       return tab[h].c;
  99     }
 100     if (++h == size) {
 101       h = 0;
 102     }
 103   }
 104   return 0;
 105 }
 106
 107 int NameToCharCode::hash(char *name) {
 108   char *p;
 109   unsigned int h;
 110
 111   h = 0;
 112   for (p = name; *p; ++p) {
 113     h = 17 * h + (int)(*p & 0xff);
 114   }
 115   return (int)(h % size);
 116 }