thirdparty/freetype-2.3.12/src/gxvalid/gxvlcar.c

   1 /***************************************************************************/
   2 /*                                                                         */
   3 /*  gxvlcar.c                                                              */
   4 /*                                                                         */
   5 /*    TrueTypeGX/AAT lcar table validation (body).                         */
   6 /*                                                                         */
   7 /*  Copyright 2004, 2005 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */
   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 /*                                                                         */
  20 /* gxvalid is derived from both gxlayout module and otvalid module.        */
  21 /* Development of gxlayout is supported by the Information-technology      */
  22 /* Promotion Agency(IPA), Japan.                                           */
  23 /*                                                                         */
  24 /***************************************************************************/
  25
  26
  27 #include "gxvalid.h"
  28 #include "gxvcommn.h"
  29
  30
  31   /*************************************************************************/
  32   /*                                                                       */
  33   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  34   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  35   /* messages during execution.                                            */
  36   /*                                                                       */
  37 #undef  FT_COMPONENT
  38 #define FT_COMPONENT  trace_gxvlcar
  39
  40
  41   /*************************************************************************/
  42   /*************************************************************************/
  43   /*****                                                               *****/
  44   /*****                      Data and Types                           *****/
  45   /*****                                                               *****/
  46   /*************************************************************************/
  47   /*************************************************************************/
  48
  49   typedef struct  GXV_lcar_DataRec_
  50   {
  51     FT_UShort  format;
  52
  53   } GXV_lcar_DataRec, *GXV_lcar_Data;
  54
  55
  56 #define GXV_LCAR_DATA( FIELD )  GXV_TABLE_DATA( lcar, FIELD )
  57
  58
  59   /*************************************************************************/
  60   /*************************************************************************/
  61   /*****                                                               *****/
  62   /*****                      UTILITY FUNCTIONS                        *****/
  63   /*****                                                               *****/
  64   /*************************************************************************/
  65   /*************************************************************************/
  66
  67   static void
  68   gxv_lcar_partial_validate( FT_UShort      partial,
  69                              FT_UShort      glyph,
  70                              GXV_Validator  valid )
  71   {
  72     GXV_NAME_ENTER( "partial" );
  73
  74     if ( GXV_LCAR_DATA( format ) != 1 )
  75       goto Exit;
  76
  77     gxv_ctlPoint_validate( glyph, partial, valid );
  78
  79   Exit:
  80     GXV_EXIT;
  81   }
  82
  83
  84   static void
  85   gxv_lcar_LookupValue_validate( FT_UShort            glyph,
  86                                  GXV_LookupValueCPtr  value_p,
  87                                  GXV_Validator        valid )
  88   {
  89     FT_Bytes   p     = valid->root->base + value_p->u;
  90     FT_Bytes   limit = valid->root->limit;
  91     FT_UShort  count;
  92     FT_Short   partial;
  93     FT_UShort  i;
  94
  95
  96     GXV_NAME_ENTER( "element in lookupTable" );
  97
  98     GXV_LIMIT_CHECK( 2 );
  99     count = FT_NEXT_USHORT( p );
 100
 101     GXV_LIMIT_CHECK( 2 * count );
 102     for ( i = 0; i < count; i++ )
 103     {
 104       partial = FT_NEXT_SHORT( p );
 105       gxv_lcar_partial_validate( partial, glyph, valid );
 106     }
 107
 108     GXV_EXIT;
 109   }
 110
 111
 112   /*
 113     +------ lcar --------------------+
 114     |                                |
 115     |      +===============+         |
 116     |      | looup header  |         |
 117     |      +===============+         |
 118     |      | BinSrchHeader |         |
 119     |      +===============+         |
 120     |      | lastGlyph[0]  |         |
 121     |      +---------------+         |
 122     |      | firstGlyph[0] |         |  head of lcar sfnt table
 123     |      +---------------+         |             +
 124     |      | offset[0]     |    ->   |          offset            [byte]
 125     |      +===============+         |             +
 126     |      | lastGlyph[1]  |         | (glyphID - firstGlyph) * 2 [byte]
 127     |      +---------------+         |
 128     |      | firstGlyph[1] |         |
 129     |      +---------------+         |
 130     |      | offset[1]     |         |
 131     |      +===============+         |
 132     |                                |
 133     |       ....                     |
 134     |                                |
 135     |      16bit value array         |
 136     |      +===============+         |
 137     +------|     value     | <-------+
 138     |       ....
 139     |
 140     |
 141     |
 142     |
 143     |
 144     +---->  lcar values...handled by lcar callback function
 145   */
 146
 147   static GXV_LookupValueDesc
 148   gxv_lcar_LookupFmt4_transit( FT_UShort            relative_gindex,
 149                                GXV_LookupValueCPtr  base_value_p,
 150                                FT_Bytes             lookuptbl_limit,
 151                                GXV_Validator        valid )
 152   {
 153     FT_Bytes             p;
 154     FT_Bytes             limit;
 155     FT_UShort            offset;
 156     GXV_LookupValueDesc  value;
 157
 158     FT_UNUSED( lookuptbl_limit );
 159
 160     /* XXX: check range? */
 161     offset = (FT_UShort)( base_value_p->u +
 162                           relative_gindex * sizeof ( FT_UShort ) );
 163     p      = valid->root->base + offset;
 164     limit  = valid->root->limit;
 165
 166     GXV_LIMIT_CHECK ( 2 );
 167     value.u = FT_NEXT_USHORT( p );
 168
 169     return value;
 170   }
 171
 172
 173   /*************************************************************************/
 174   /*************************************************************************/
 175   /*****                                                               *****/
 176   /*****                          lcar TABLE                           *****/
 177   /*****                                                               *****/
 178   /*************************************************************************/
 179   /*************************************************************************/
 180
 181   FT_LOCAL_DEF( void )
 182   gxv_lcar_validate( FT_Bytes      table,
 183                      FT_Face       face,
 184                      FT_Validator  ftvalid )
 185   {
 186     FT_Bytes          p     = table;
 187     FT_Bytes          limit = 0;
 188     GXV_ValidatorRec  validrec;
 189     GXV_Validator     valid = &validrec;
 190
 191     GXV_lcar_DataRec  lcarrec;
 192     GXV_lcar_Data     lcar = &lcarrec;
 193
 194     FT_Fixed          version;
 195
 196
 197     valid->root       = ftvalid;
 198     valid->table_data = lcar;
 199     valid->face       = face;
 200
 201     FT_TRACE3(( "validating `lcar' table\n" ));
 202     GXV_INIT;
 203
 204     GXV_LIMIT_CHECK( 4 + 2 );
 205     version = FT_NEXT_ULONG( p );
 206     GXV_LCAR_DATA( format ) = FT_NEXT_USHORT( p );
 207
 208     if ( version != 0x00010000UL)
 209       FT_INVALID_FORMAT;
 210
 211     if ( GXV_LCAR_DATA( format ) > 1 )
 212       FT_INVALID_FORMAT;
 213
 214     valid->lookupval_sign   = GXV_LOOKUPVALUE_UNSIGNED;
 215     valid->lookupval_func   = gxv_lcar_LookupValue_validate;
 216     valid->lookupfmt4_trans = gxv_lcar_LookupFmt4_transit;
 217     gxv_LookupTable_validate( p, limit, valid );
 218
 219     FT_TRACE4(( "\n" ));
 220   }
 221
 222
 223 /* END */