reactos/lib/3rdparty/freetype/src/pfr/pfrcmap.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  pfrcmap.c                                                              */
   4 /*                                                                         */
   5 /*    FreeType PFR cmap handling (body).                                   */
   6 /*                                                                         */
   7 /*  Copyright 2002, 2007 by                                                */
   8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
   9 /*                                                                         */
  10 /*  This file is part of the FreeType project, and may only be used,       */
  11 /*  modified, and distributed under the terms of the FreeType project      */
  12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
  13 /*  this file you indicate that you have read the license and              */
  14 /*  understand and accept it fully.                                        */
  15 /*                                                                         */
  16 /***************************************************************************/
  17
  18
  19 #include "pfrcmap.h"
  20 #include "pfrobjs.h"
  21 #include FT_INTERNAL_DEBUG_H
  22
  23
  24   FT_CALLBACK_DEF( FT_Error )
  25   pfr_cmap_init( PFR_CMap  cmap )
  26   {
  27     FT_Error  error = PFR_Err_Ok;
  28     PFR_Face  face  = (PFR_Face)FT_CMAP_FACE( cmap );
  29
  30
  31     cmap->num_chars = face->phy_font.num_chars;
  32     cmap->chars     = face->phy_font.chars;
  33
  34     /* just for safety, check that the character entries are correctly */
  35     /* sorted in increasing character code order                       */
  36     {
  37       FT_UInt  n;
  38
  39
  40       for ( n = 1; n < cmap->num_chars; n++ )
  41       {
  42         if ( cmap->chars[n - 1].char_code >= cmap->chars[n].char_code )
  43         {
  44           error = PFR_Err_Invalid_Table;
  45           goto Exit;
  46         }
  47       }
  48     }
  49
  50   Exit:
  51     return error;
  52   }
  53
  54
  55   FT_CALLBACK_DEF( void )
  56   pfr_cmap_done( PFR_CMap  cmap )
  57   {
  58     cmap->chars     = NULL;
  59     cmap->num_chars = 0;
  60   }
  61
  62
  63   FT_CALLBACK_DEF( FT_UInt )
  64   pfr_cmap_char_index( PFR_CMap   cmap,
  65                        FT_UInt32  char_code )
  66   {
  67     FT_UInt   min = 0;
  68     FT_UInt   max = cmap->num_chars;
  69     FT_UInt   mid;
  70     PFR_Char  gchar;
  71
  72
  73     while ( min < max )
  74     {
  75       mid   = min + ( max - min ) / 2;
  76       gchar = cmap->chars + mid;
  77
  78       if ( gchar->char_code == char_code )
  79         return mid + 1;
  80
  81       if ( gchar->char_code < char_code )
  82         min = mid + 1;
  83       else
  84         max = mid;
  85     }
  86     return 0;
  87   }
  88
  89
  90   FT_CALLBACK_DEF( FT_UInt )
  91   pfr_cmap_char_next( PFR_CMap    cmap,
  92                       FT_UInt32  *pchar_code )
  93   {
  94     FT_UInt    result    = 0;
  95     FT_UInt32  char_code = *pchar_code + 1;
  96
  97
  98   Restart:
  99     {
 100       FT_UInt   min = 0;
 101       FT_UInt   max = cmap->num_chars;
 102       FT_UInt   mid;
 103       PFR_Char  gchar;
 104
 105
 106       while ( min < max )
 107       {
 108         mid   = min + ( ( max - min ) >> 1 );
 109         gchar = cmap->chars + mid;
 110
 111         if ( gchar->char_code == char_code )
 112         {
 113           result = mid;
 114           if ( result != 0 )
 115           {
 116             result++;
 117             goto Exit;
 118           }
 119
 120           char_code++;
 121           goto Restart;
 122         }
 123
 124         if ( gchar->char_code < char_code )
 125           min = mid+1;
 126         else
 127           max = mid;
 128       }
 129
 130       /* we didn't find it, but we have a pair just above it */
 131       char_code = 0;
 132
 133       if ( min < cmap->num_chars )
 134       {
 135         gchar  = cmap->chars + min;
 136         result = min;
 137         if ( result != 0 )
 138         {
 139           result++;
 140           char_code = gchar->char_code;
 141         }
 142       }
 143     }
 144
 145   Exit:
 146     *pchar_code = char_code;
 147     return result;
 148   }
 149
 150
 151   FT_CALLBACK_TABLE_DEF const FT_CMap_ClassRec
 152   pfr_cmap_class_rec =
 153   {
 154     sizeof ( PFR_CMapRec ),
 155
 156     (FT_CMap_InitFunc)     pfr_cmap_init,
 157     (FT_CMap_DoneFunc)     pfr_cmap_done,
 158     (FT_CMap_CharIndexFunc)pfr_cmap_char_index,
 159     (FT_CMap_CharNextFunc) pfr_cmap_char_next
 160   };
 161
 162
 163 /* END */