otvcommn.c

winNT技术操作系统,国外开放的原代码和LIUX一样

    LangSysCount   = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (LangSysCount = %d)\n", LangSysCount ));

    if ( DefaultLangSys != 0 )
      otv_LangSys_validate( table + DefaultLangSys, valid );

    OTV_LIMIT_CHECK( LangSysCount * 6 );

    /* LangSysRecord */
    for ( ; LangSysCount > 0; LangSysCount-- )
    {
      p += 4;       /* skip LangSysTag */

      /* LangSys */
      otv_LangSys_validate( table + FT_NEXT_USHORT( p ), valid );
    }

    OTV_EXIT;
  }


  /* sets valid->extra1 (number of features) */

  FT_LOCAL_DEF( void )
  otv_ScriptList_validate( FT_Bytes       table,
                           FT_Bytes       features,
                           OTV_Validator  valid )
  {
    FT_UInt   ScriptCount;
    FT_Bytes  p = table;


    OTV_NAME_ENTER( "ScriptList" );

    OTV_LIMIT_CHECK( 2 );
    ScriptCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (ScriptCount = %d)\n", ScriptCount ));

    OTV_LIMIT_CHECK( ScriptCount * 6 );

    valid->extra1 = otv_Feature_get_count( features );

    /* ScriptRecord */
    for ( ; ScriptCount > 0; ScriptCount-- )
    {
      p += 4;       /* skip ScriptTag */

      otv_Script_validate( table + FT_NEXT_USHORT( p ), valid ); /* Script */
    }

    OTV_EXIT;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                      UTILITY FUNCTIONS                        *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

  /*
     u:   uint16
     ux:  unit16 [x]

     s:   struct
     sx:  struct [x]
     sxy: struct [x], using external y count

     x:   uint16 x

     C:   Coverage

     O:   Offset
     On:  Offset (NULL)
     Ox:  Offset [x]
     Onx: Offset (NULL) [x]
  */

  FT_LOCAL_DEF( void )
  otv_x_Ox( FT_Bytes       table,
            OTV_Validator  valid )
  {
    FT_Bytes           p = table;
    FT_UInt            Count;
    OTV_Validate_Func  func;


    OTV_ENTER;

    OTV_LIMIT_CHECK( 2 );
    Count = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (Count = %d)\n", Count ));

    OTV_LIMIT_CHECK( Count * 2 );

    valid->nesting_level++;
    func = valid->func[valid->nesting_level];

    for ( ; Count > 0; Count-- )
      func( table + FT_NEXT_USHORT( p ), valid );

    valid->nesting_level--;

    OTV_EXIT;
  }


  FT_LOCAL_DEF( void )
  otv_u_C_x_Ox( FT_Bytes       table,
                OTV_Validator  valid )
  {
    FT_Bytes           p = table;
    FT_UInt            Count, Coverage;
    OTV_Validate_Func  func;


    OTV_ENTER;

    p += 2;     /* skip Format */

    OTV_LIMIT_CHECK( 4 );
    Coverage = FT_NEXT_USHORT( p );
    Count    = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (Count = %d)\n", Count ));

    otv_Coverage_validate( table + Coverage, valid );

    OTV_LIMIT_CHECK( Count * 2 );

    valid->nesting_level++;
    func = valid->func[valid->nesting_level];

    for ( ; Count > 0; Count-- )
      func( table + FT_NEXT_USHORT( p ), valid );

    valid->nesting_level--;

    OTV_EXIT;
  }


  /* uses valid->extra1 (if > 0: array value limit) */

  FT_LOCAL_DEF( void )
  otv_x_ux( FT_Bytes       table,
            OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   Count;


    OTV_ENTER;

    OTV_LIMIT_CHECK( 2 );
    Count = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (Count = %d)\n", Count ));

    OTV_LIMIT_CHECK( Count * 2 );

    if ( valid->extra1 )
    {
      for ( ; Count > 0; Count-- )
        if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
          FT_INVALID_DATA;
    }

    OTV_EXIT;
  }


  /* `ux' in the function's name is not really correct since only x-1 */
  /* elements are tested                                              */

  /* uses valid->extra1 (array value limit) */

  FT_LOCAL_DEF( void )
  otv_x_y_ux_sy( FT_Bytes       table,
                 OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   Count1, Count2;


    OTV_ENTER;

    OTV_LIMIT_CHECK( 4 );
    Count1 = FT_NEXT_USHORT( p );
    Count2 = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (Count1 = %d)\n", Count1 ));
    OTV_TRACE(( " (Count2 = %d)\n", Count2 ));

    if ( Count1 == 0 )
      FT_INVALID_DATA;

    OTV_LIMIT_CHECK( ( Count1 - 1 ) * 2 + Count2 * 4 );

    for ( ; Count2 > 0; Count2-- )
    {
      if ( FT_NEXT_USHORT( p ) >= Count1 )
        FT_INVALID_DATA;

      if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
        FT_INVALID_DATA;
    }

    OTV_EXIT;
  }


  /* `uy' in the function's name is not really correct since only y-1 */
  /* elements are tested                                              */

  /* uses valid->extra1 (array value limit) */

  FT_LOCAL_DEF( void )
  otv_x_ux_y_uy_z_uz_p_sp( FT_Bytes       table,
                           OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   BacktrackCount, InputCount, LookaheadCount;
    FT_UInt   Count;


    OTV_ENTER;

    OTV_LIMIT_CHECK( 2 );
    BacktrackCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (BacktrackCount = %d)\n", BacktrackCount ));

    OTV_LIMIT_CHECK( BacktrackCount * 2 + 2 );
    p += BacktrackCount * 2;

    InputCount = FT_NEXT_USHORT( p );
    if ( InputCount == 0 )
      FT_INVALID_DATA;

    OTV_TRACE(( " (InputCount = %d)\n", InputCount ));

    OTV_LIMIT_CHECK( InputCount * 2 );
    p += ( InputCount - 1 ) * 2;

    LookaheadCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (LookaheadCount = %d)\n", LookaheadCount ));

    OTV_LIMIT_CHECK( LookaheadCount * 2 + 2 );
    p += LookaheadCount * 2;

    Count = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (Count = %d)\n", Count ));

    OTV_LIMIT_CHECK( Count * 4 );

    for ( ; Count > 0; Count-- )
    {
      if ( FT_NEXT_USHORT( p ) >= InputCount )
        FT_INVALID_DATA;

      if ( FT_NEXT_USHORT( p ) >= valid->extra1 )
        FT_INVALID_DATA;
    }

    OTV_EXIT;
  }


  /* sets valid->extra1 (valid->lookup_count) */

  FT_LOCAL_DEF( void )
  otv_u_O_O_x_Onx( FT_Bytes       table,
                   OTV_Validator  valid )
  {
    FT_Bytes           p = table;
    FT_UInt            Coverage, ClassDef, ClassSetCount;
    OTV_Validate_Func  func;


    OTV_ENTER;

    p += 2;     /* skip Format */

    OTV_LIMIT_CHECK( 6 );
    Coverage      = FT_NEXT_USHORT( p );
    ClassDef      = FT_NEXT_USHORT( p );
    ClassSetCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (ClassSetCount = %d)\n", ClassSetCount ));

    otv_Coverage_validate( table + Coverage, valid );
    otv_ClassDef_validate( table + ClassDef, valid );

    OTV_LIMIT_CHECK( ClassSetCount * 2 );

    valid->nesting_level++;
    func          = valid->func[valid->nesting_level];
    valid->extra1 = valid->lookup_count;

    for ( ; ClassSetCount > 0; ClassSetCount-- )
    {
      FT_UInt  offset = FT_NEXT_USHORT( p );


      if ( offset )
        func( table + offset, valid );
    }

    valid->nesting_level--;

    OTV_EXIT;
  }


  /* uses valid->lookup_count */

  FT_LOCAL_DEF( void )
  otv_u_x_y_Ox_sy( FT_Bytes       table,
                   OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   GlyphCount, Count, count1;


    OTV_ENTER;

    p += 2;     /* skip Format */

    OTV_LIMIT_CHECK( 4 );
    GlyphCount = FT_NEXT_USHORT( p );
    Count      = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (GlyphCount = %d)\n", GlyphCount ));
    OTV_TRACE(( " (Count = %d)\n",      Count      ));

    OTV_LIMIT_CHECK( GlyphCount * 2 + Count * 4 );

    for ( count1 = GlyphCount; count1 > 0; count1-- )
      otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid );

    for ( ; Count > 0; Count-- )
    {
      if ( FT_NEXT_USHORT( p ) >= GlyphCount )
        FT_INVALID_DATA;

      if ( FT_NEXT_USHORT( p ) >= valid->lookup_count )
        FT_INVALID_DATA;
    }

    OTV_EXIT;
  }


  /* sets valid->extra1 (valid->lookup_count)    */

  FT_LOCAL_DEF( void )
  otv_u_O_O_O_O_x_Onx( FT_Bytes       table,
                       OTV_Validator  valid )
  {
    FT_Bytes           p = table;
    FT_UInt            Coverage;
    FT_UInt            BacktrackClassDef, InputClassDef, LookaheadClassDef;
    FT_UInt            ChainClassSetCount;
    OTV_Validate_Func  func;


    OTV_ENTER;

    p += 2;     /* skip Format */

    OTV_LIMIT_CHECK( 10 );
    Coverage           = FT_NEXT_USHORT( p );
    BacktrackClassDef  = FT_NEXT_USHORT( p );
    InputClassDef      = FT_NEXT_USHORT( p );
    LookaheadClassDef  = FT_NEXT_USHORT( p );
    ChainClassSetCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (ChainClassSetCount = %d)\n", ChainClassSetCount ));

    otv_Coverage_validate( table + Coverage, valid );

    otv_ClassDef_validate( table + BacktrackClassDef,  valid );
    otv_ClassDef_validate( table + InputClassDef, valid );
    otv_ClassDef_validate( table + LookaheadClassDef, valid );

    OTV_LIMIT_CHECK( ChainClassSetCount * 2 );

    valid->nesting_level++;
    func          = valid->func[valid->nesting_level];
    valid->extra1 = valid->lookup_count;

    for ( ; ChainClassSetCount > 0; ChainClassSetCount-- )
    {
      FT_UInt  offset = FT_NEXT_USHORT( p );


      if ( offset )
        func( table + offset, valid );
    }

    valid->nesting_level--;

    OTV_EXIT;
  }


  /* uses valid->lookup_count */

  FT_LOCAL_DEF( void )
  otv_u_x_Ox_y_Oy_z_Oz_p_sp( FT_Bytes       table,
                             OTV_Validator  valid )
  {
    FT_Bytes  p = table;
    FT_UInt   BacktrackGlyphCount, InputGlyphCount, LookaheadGlyphCount;
    FT_UInt   count1, count2;


    OTV_ENTER;

    p += 2;     /* skip Format */

    OTV_LIMIT_CHECK( 2 );
    BacktrackGlyphCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (BacktrackGlyphCount = %d)\n", BacktrackGlyphCount ));

    OTV_LIMIT_CHECK( BacktrackGlyphCount * 2 + 2 );

    for ( ; BacktrackGlyphCount > 0; BacktrackGlyphCount-- )
      otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid );

    InputGlyphCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (InputGlyphCount = %d)\n", InputGlyphCount ));

    OTV_LIMIT_CHECK( InputGlyphCount * 2 + 2 );

    for ( count1 = InputGlyphCount; count1 > 0; count1-- )
      otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid );

    LookaheadGlyphCount = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (LookaheadGlyphCount = %d)\n", LookaheadGlyphCount ));

    OTV_LIMIT_CHECK( LookaheadGlyphCount * 2 + 2 );

    for ( ; LookaheadGlyphCount > 0; LookaheadGlyphCount-- )
      otv_Coverage_validate( table + FT_NEXT_USHORT( p ), valid );

    count2 = FT_NEXT_USHORT( p );

    OTV_TRACE(( " (Count = %d)\n", count2 ));

    OTV_LIMIT_CHECK( count2 * 4 );

    for ( ; count2 > 0; count2-- )
    {
      if ( FT_NEXT_USHORT( p ) >= InputGlyphCount )
        FT_INVALID_DATA;

      if ( FT_NEXT_USHORT( p ) >= valid->lookup_count )
        FT_INVALID_DATA;
    }

    OTV_EXIT;
  }


  FT_LOCAL_DEF( FT_UInt )
  otv_GSUBGPOS_get_Lookup_count( FT_Bytes  table )
  {
    FT_Bytes  p = table + 8;


    return otv_LookupList_get_count( table + FT_NEXT_USHORT( p ) );
  }


  FT_LOCAL_DEF( FT_UInt )
  otv_GSUBGPOS_have_MarkAttachmentType_flag( FT_Bytes  table )
  {
    FT_Bytes  p, lookup;
    FT_UInt   count;


    if ( !table )
      return 0;

    /* LookupList */
    p      = table + 8;
    table += FT_NEXT_USHORT( p );

    /* LookupCount */
    p     = table;
    count = FT_NEXT_USHORT( p );

    for ( ; count > 0; count-- )
    {
      FT_Bytes  oldp;


      /* Lookup */
      lookup = table + FT_NEXT_USHORT( p );

      oldp = p;

      /* LookupFlag */
      p = lookup + 2;
      if ( FT_NEXT_USHORT( p ) & 0xFF00U )
        return 1;

      p = oldp;
    }

    return 0;
  }


/* END */