otvbase.c

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/***************************************************************************/
/*                                                                         */
/*  otvbase.c                                                              */
/*                                                                         */
/*    OpenType BASE table validation (body).                               */
/*                                                                         */
/*  Copyright 2004-2018 by                                                 */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/
 
 
#include "otvalid.h"
#include "otvcommn.h"
 
 
  /*************************************************************************/
  /*                                                                       */
  /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
  /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
  /* messages during execution.                                            */
  /*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT  trace_otvbase
 
 
  static void
  otv_BaseCoord_validate( FT_Bytes       table,
                          OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   BaseCoordFormat;
 
 
    OTV_NAME_ENTER( "BaseCoord" );
 
    OTV_LIMIT_CHECK( 4 );
    BaseCoordFormat = FT_NEXT_USHORT( p );
    p += 2;     /* skip Coordinate */
 
    OTV_TRACE(( " (format %d)\n", BaseCoordFormat ));
 
    switch ( BaseCoordFormat )
    {
    case 1:     /* BaseCoordFormat1 */
      break;
 
    case 2:     /* BaseCoordFormat2 */
      OTV_LIMIT_CHECK( 4 );   /* ReferenceGlyph, BaseCoordPoint */
      break;
 
    case 3:     /* BaseCoordFormat3 */
      OTV_LIMIT_CHECK( 2 );
      /* DeviceTable */
      otv_Device_validate( table + FT_NEXT_USHORT( p ), otvalid );
      break;
 
    default:
      FT_INVALID_FORMAT;
    }
 
    OTV_EXIT;
  }
 
 
  static void
  otv_BaseTagList_validate( FT_Bytes       table,
                            OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   BaseTagCount;
 
 
    OTV_NAME_ENTER( "BaseTagList" );
 
    OTV_LIMIT_CHECK( 2 );
 
    BaseTagCount = FT_NEXT_USHORT( p );
 
    OTV_TRACE(( " (BaseTagCount = %d)\n", BaseTagCount ));
 
    OTV_LIMIT_CHECK( BaseTagCount * 4 );          /* BaselineTag */
 
    OTV_EXIT;
  }
 
 
  static void
  otv_BaseValues_validate( FT_Bytes       table,
                           OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   BaseCoordCount;
 
 
    OTV_NAME_ENTER( "BaseValues" );
 
    OTV_LIMIT_CHECK( 4 );
 
    p             += 2;                     /* skip DefaultIndex */
    BaseCoordCount = FT_NEXT_USHORT( p );
 
    OTV_TRACE(( " (BaseCoordCount = %d)\n", BaseCoordCount ));
 
    OTV_LIMIT_CHECK( BaseCoordCount * 2 );
 
    /* BaseCoord */
    for ( ; BaseCoordCount > 0; BaseCoordCount-- )
      otv_BaseCoord_validate( table + FT_NEXT_USHORT( p ), otvalid );
 
    OTV_EXIT;
  }
 
 
  static void
  otv_MinMax_validate( FT_Bytes       table,
                       OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   table_size;
    FT_UInt   FeatMinMaxCount;
 
    OTV_OPTIONAL_TABLE( MinCoord );
    OTV_OPTIONAL_TABLE( MaxCoord );
 
 
    OTV_NAME_ENTER( "MinMax" );
 
    OTV_LIMIT_CHECK( 6 );
 
    OTV_OPTIONAL_OFFSET( MinCoord );
    OTV_OPTIONAL_OFFSET( MaxCoord );
    FeatMinMaxCount = FT_NEXT_USHORT( p );
 
    OTV_TRACE(( " (FeatMinMaxCount = %d)\n", FeatMinMaxCount ));
 
    table_size = FeatMinMaxCount * 8 + 6;
 
    OTV_SIZE_CHECK( MinCoord );
    if ( MinCoord )
      otv_BaseCoord_validate( table + MinCoord, otvalid );
 
    OTV_SIZE_CHECK( MaxCoord );
    if ( MaxCoord )
      otv_BaseCoord_validate( table + MaxCoord, otvalid );
 
    OTV_LIMIT_CHECK( FeatMinMaxCount * 8 );
 
    /* FeatMinMaxRecord */
    for ( ; FeatMinMaxCount > 0; FeatMinMaxCount-- )
    {
      p += 4;                           /* skip FeatureTableTag */
 
      OTV_OPTIONAL_OFFSET( MinCoord );
      OTV_OPTIONAL_OFFSET( MaxCoord );
 
      OTV_SIZE_CHECK( MinCoord );
      if ( MinCoord )
        otv_BaseCoord_validate( table + MinCoord, otvalid );
 
      OTV_SIZE_CHECK( MaxCoord );
      if ( MaxCoord )
        otv_BaseCoord_validate( table + MaxCoord, otvalid );
    }
 
    OTV_EXIT;
  }
 
 
  static void
  otv_BaseScript_validate( FT_Bytes       table,
                           OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   table_size;
    FT_UInt   BaseLangSysCount;
 
    OTV_OPTIONAL_TABLE( BaseValues    );
    OTV_OPTIONAL_TABLE( DefaultMinMax );
 
 
    OTV_NAME_ENTER( "BaseScript" );
 
    OTV_LIMIT_CHECK( 6 );
    OTV_OPTIONAL_OFFSET( BaseValues    );
    OTV_OPTIONAL_OFFSET( DefaultMinMax );
    BaseLangSysCount = FT_NEXT_USHORT( p );
 
    OTV_TRACE(( " (BaseLangSysCount = %d)\n", BaseLangSysCount ));
 
    table_size = BaseLangSysCount * 6 + 6;
 
    OTV_SIZE_CHECK( BaseValues );
    if ( BaseValues )
      otv_BaseValues_validate( table + BaseValues, otvalid );
 
    OTV_SIZE_CHECK( DefaultMinMax );
    if ( DefaultMinMax )
      otv_MinMax_validate( table + DefaultMinMax, otvalid );
 
    OTV_LIMIT_CHECK( BaseLangSysCount * 6 );
 
    /* BaseLangSysRecord */
    for ( ; BaseLangSysCount > 0; BaseLangSysCount-- )
    {
      p += 4;       /* skip BaseLangSysTag */
 
      otv_MinMax_validate( table + FT_NEXT_USHORT( p ), otvalid );
    }
 
    OTV_EXIT;
  }
 
 
  static void
  otv_BaseScriptList_validate( FT_Bytes       table,
                               OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   BaseScriptCount;
 
 
    OTV_NAME_ENTER( "BaseScriptList" );
 
    OTV_LIMIT_CHECK( 2 );
    BaseScriptCount = FT_NEXT_USHORT( p );
 
    OTV_TRACE(( " (BaseScriptCount = %d)\n", BaseScriptCount ));
 
    OTV_LIMIT_CHECK( BaseScriptCount * 6 );
 
    /* BaseScriptRecord */
    for ( ; BaseScriptCount > 0; BaseScriptCount-- )
    {
      p += 4;       /* skip BaseScriptTag */
 
      /* BaseScript */
      otv_BaseScript_validate( table + FT_NEXT_USHORT( p ), otvalid );
    }
 
    OTV_EXIT;
  }
 
 
  static void
  otv_Axis_validate( FT_Bytes       table,
                     OTV_Validator  otvalid )
  {
    FT_Bytes  p = table;
    FT_UInt   table_size;
 
    OTV_OPTIONAL_TABLE( BaseTagList );
 
 
    OTV_NAME_ENTER( "Axis" );
 
    OTV_LIMIT_CHECK( 4 );
    OTV_OPTIONAL_OFFSET( BaseTagList );
 
    table_size = 4;
 
    OTV_SIZE_CHECK( BaseTagList );
    if ( BaseTagList )
      otv_BaseTagList_validate( table + BaseTagList, otvalid );
 
    /* BaseScriptList */
    otv_BaseScriptList_validate( table + FT_NEXT_USHORT( p ), otvalid );
 
    OTV_EXIT;
  }
 
 
  FT_LOCAL_DEF( void )
  otv_BASE_validate( FT_Bytes      table,
                     FT_Validator  ftvalid )
  {
    OTV_ValidatorRec  otvalidrec;
    OTV_Validator     otvalid = &otvalidrec;
    FT_Bytes          p       = table;
    FT_UInt           table_size;
    FT_UShort         version;
 
    OTV_OPTIONAL_TABLE( HorizAxis );
    OTV_OPTIONAL_TABLE( VertAxis  );
 
    OTV_OPTIONAL_TABLE32( itemVarStore );
 
 
    otvalid->root = ftvalid;
 
    FT_TRACE3(( "validating BASE table\n" ));
    OTV_INIT;
 
    OTV_LIMIT_CHECK( 4 );
 
    if ( FT_NEXT_USHORT( p ) != 1 )  /* majorVersion */
      FT_INVALID_FORMAT;
 
    version = FT_NEXT_USHORT( p );   /* minorVersion */
 
    table_size = 8;
    switch ( version )
    {
    case 0:
      OTV_LIMIT_CHECK( 4 );
      break;
 
    case 1:
      OTV_LIMIT_CHECK( 8 );
      table_size += 4;
      break;
 
    default:
      FT_INVALID_FORMAT;
    }
 
    OTV_OPTIONAL_OFFSET( HorizAxis );
    OTV_SIZE_CHECK( HorizAxis );
    if ( HorizAxis )
      otv_Axis_validate( table + HorizAxis, otvalid );
 
    OTV_OPTIONAL_OFFSET( VertAxis );
    OTV_SIZE_CHECK( VertAxis );
    if ( VertAxis )
      otv_Axis_validate( table + VertAxis, otvalid );
 
    if ( version > 0 )
    {
      OTV_OPTIONAL_OFFSET32( itemVarStore );
      OTV_SIZE_CHECK32( itemVarStore );
      if ( itemVarStore )
        OTV_TRACE(( "  [omitting itemVarStore validation]\n" )); /* XXX */
    }
 
    FT_TRACE4(( "\n" ));
  }
 
 
/* END */