text: /***************************************************************************/
  /*                                                                         */
  /*  gxvprop.c                                                              */
  /*                                                                         */
  /*    TrueTypeGX/AAT prop table validation (body).                         */
  /*                                                                         */
  /*  Copyright 2004, 2005 by suzuki toshiya, Masatake YAMATO, Red Hat K.K., */
  /*  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.                                        */
  /*                                                                         */
  /***************************************************************************/
  
  /***************************************************************************/
  /*                                                                         */
  /* gxvalid is derived from both gxlayout module and otvalid module.        */
  /* Development of gxlayout is supported by the Information-technology      */
  /* Promotion Agency(IPA), Japan.                                           */
  /*                                                                         */
  /***************************************************************************/
  
  
  #include "gxvalid.h"
  #include "gxvcommn.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_gxvprop
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                      Data and Types                           *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
  #define GXV_PROP_HEADER_SIZE  ( 4 + 2 + 2 )
  #define GXV_PROP_SIZE_MIN     GXV_PROP_HEADER_SIZE
  
    typedef struct  GXV_prop_DataRec_
    {
      FT_Fixed  version;
  
    } GXV_prop_DataRec, *GXV_prop_Data;
  
  #define GXV_PROP_DATA( field )  GXV_TABLE_DATA( prop, field )
  
  #define GXV_PROP_FLOATER                      0x8000U
  #define GXV_PROP_USE_COMPLEMENTARY_BRACKET    0x1000U
  #define GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET 0x0F00U
  #define GXV_PROP_ATTACHING_TO_RIGHT           0x0080U
  #define GXV_PROP_RESERVED                     0x0060U
  #define GXV_PROP_DIRECTIONALITY_CLASS         0x001FU
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                      UTILITY FUNCTIONS                        *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    static void
    gxv_prop_zero_advance_validate( FT_UShort      gid,
                                    GXV_Validator  valid )
    {
      FT_Face       face;
      FT_Error      error;
      FT_GlyphSlot  glyph;
  
  
      GXV_NAME_ENTER( "zero advance" );
  
      face = valid->face;
  
      error = FT_Load_Glyph( face,
                             gid,
                             FT_LOAD_IGNORE_TRANSFORM );
      if ( error )
        FT_INVALID_GLYPH_ID;
  
      glyph = face->glyph;
  
      if ( glyph->advance.x != (FT_Pos)0 ||
           glyph->advance.y != (FT_Pos)0 )
        FT_INVALID_DATA;
  
      GXV_EXIT;
    }
  
  
    /* Pass 0 as GLYPH to check the default property */
    static void
    gxv_prop_property_validate( FT_UShort      property,
                                FT_UShort      glyph,
                                GXV_Validator  valid )
    {
      if ( glyph != 0 && ( property & GXV_PROP_FLOATER ) )
        gxv_prop_zero_advance_validate( glyph, valid );
  
      if ( property & GXV_PROP_USE_COMPLEMENTARY_BRACKET )
      {
        FT_UShort  offset;
        char       complement;
  
  
        offset = (FT_UShort)( property & GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET );
        if ( offset == 0 )
          FT_INVALID_DATA;
  
        complement = (char)( offset >> 8 );
        if ( complement & 0x08 )
        {
          /* Top bit is set: negative */
  
          /* Calculate the absolute offset */
          complement = (char)( ( complement & 0x07 ) + 1 );
  
          /* The gid for complement must be greater than 0 */
          if ( glyph <= complement )
            FT_INVALID_DATA;
        }
        else
        {
          /* The gid for complement must be the face. */
          gxv_glyphid_validate( (FT_UShort)( glyph + complement ), valid );
        }
      }
      else
      {
        if ( property & GXV_PROP_COMPLEMENTARY_BRACKET_OFFSET )
          GXV_TRACE(( "glyph %d cannot have complementary bracketing\n",
                      glyph ));
      }
  
      /* this is introduced in version 2.0 */
      if ( property & GXV_PROP_ATTACHING_TO_RIGHT )
      {
        if ( GXV_PROP_DATA( version ) == 0x00010000UL )
          FT_INVALID_DATA;
      }
  
      if ( property & GXV_PROP_RESERVED )
        FT_INVALID_DATA;
  
      if ( ( property & GXV_PROP_DIRECTIONALITY_CLASS ) > 11 )
      {
        /* TODO: Too restricted. Use the validation level. */
        if ( GXV_PROP_DATA( version ) == 0x00010000UL ||
             GXV_PROP_DATA( version ) == 0x00020000UL )
          FT_INVALID_DATA;
      }
    }
  
  
    static void
    gxv_prop_LookupValue_validate( FT_UShort            glyph,
                                   GXV_LookupValueCPtr  value_p,
                                   GXV_Validator        valid )
    {
      gxv_prop_property_validate( value_p->u, glyph, valid );
    }
  
  
    /*
      +===============+ --------+
      | lookup header |         |
      +===============+         |
      | BinSrchHeader |         |
      +===============+         |
      | lastGlyph[0]  |         |
      +---------------+         |
      | firstGlyph[0] |         |    head of lookup table
      +---------------+         |             +
      | offset[0]     |    ->   |          offset            [byte]
      +===============+         |             +
      | lastGlyph[1]  |         | (glyphID - firstGlyph) * 2 [byte]
      +---------------+         |
      | firstGlyph[1] |         |
      +---------------+         |
      | offset[1]     |         |
      +===============+         |
                                |
       ...                      |
                                |
      16bit value array         |
      +===============+         |
      |     value     | <-------+
      ...
    */
  
    static GXV_LookupValueDesc
    gxv_prop_LookupFmt4_transit( FT_UShort            relative_gindex,
                                 GXV_LookupValueCPtr  base_value_p,
                                 FT_Bytes             lookuptbl_limit,
                                 GXV_Validator        valid )
    {
      FT_Bytes             p;
      FT_Bytes             limit;
      FT_UShort            offset;
      GXV_LookupValueDesc  value;
  
      /* XXX: check range? */
      offset = (FT_UShort)( base_value_p->u +
                            relative_gindex * sizeof( FT_UShort ) );
      p      = valid->lookuptbl_head + offset;
      limit  = lookuptbl_limit;
  
      GXV_LIMIT_CHECK ( 2 );
      value.u = FT_NEXT_USHORT( p );
  
      return value;
    }
  
  
    /*************************************************************************/
    /*************************************************************************/
    /*****                                                               *****/
    /*****                         prop TABLE                            *****/
    /*****                                                               *****/
    /*************************************************************************/
    /*************************************************************************/
  
    FT_LOCAL_DEF( void )
    gxv_prop_validate( FT_Bytes      table,
                       FT_Face       face,
                       FT_Validator  ftvalid )
    {
      FT_Bytes          p     = table;
      FT_Bytes          limit = 0;
      GXV_ValidatorRec  validrec;
      GXV_Validator     valid = &validrec;
  
      GXV_prop_DataRec  proprec;
      GXV_prop_Data     prop = &proprec;
  
      FT_Fixed          version;
      FT_UShort         format;
      FT_UShort         defaultProp;
  
  
      valid->root       = ftvalid;
      valid->table_data = prop;
      valid->face       = face;
  
      FT_TRACE3(( "validating `prop' table\n" ));
      GXV_INIT;
  
      GXV_LIMIT_CHECK( 4 + 2 + 2 );
      version     = FT_NEXT_ULONG( p );
      format      = FT_NEXT_USHORT( p );
      defaultProp = FT_NEXT_USHORT( p );
  
      /* only versions 1.0, 2.0, 3.0 are defined (1996) */
      if ( version != 0x00010000UL &&
           version != 0x00020000UL &&
           version != 0x00030000UL )
        FT_INVALID_FORMAT;
  
  
      /* only formats 0x0000, 0x0001 are defined (1996) */
      if ( format > 1 )
        FT_INVALID_FORMAT;
  
      gxv_prop_property_validate( defaultProp, 0, valid );
  
      if ( format == 0 )
      {
        FT_TRACE3(( "(format 0, no per-glyph properties, "
                    "remaining %d bytes are skipped)", limit - p ));
        goto Exit;
      }
  
      /* format == 1 */
      GXV_PROP_DATA( version ) = version;
  
      valid->lookupval_sign   = GXV_LOOKUPVALUE_UNSIGNED;
      valid->lookupval_func   = gxv_prop_LookupValue_validate;
      valid->lookupfmt4_trans = gxv_prop_LookupFmt4_transit;
  
      gxv_LookupTable_validate( p, limit, valid );
  
    Exit:
      FT_TRACE4(( "\n" ));
    }
  
  
  /* END */
  