/***************************************************************************/

/*                                                                         */

/*  gxvtrak.c                                                              */

/*                                                                         */

/*    TrueTypeGX/AAT trak 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_gxvtrak

  /*************************************************************************/

  /*************************************************************************/

  /*****                                                               *****/

  /*****                      Data and Types                           *****/

  /*****                                                               *****/

  /*************************************************************************/

  /*************************************************************************/

    /*

     * referred track table format specification:

     * http://developer.apple.com/fonts/TTRefMan/RM06/Chap6trak.html

     * last update was 1996.

     * ----------------------------------------------

     * [MINIMUM HEADER]: GXV_TRAK_SIZE_MIN

     * version          (fixed:  32bit) = 0x00010000

     * format           (uint16: 16bit) = 0 is only defined (1996)

     * horizOffset      (uint16: 16bit)

     * vertOffset       (uint16: 16bit)

     * reserved         (uint16: 16bit) = 0

     * ----------------------------------------------

     * [VARIABLE BODY]:

     * horizData

     *   header         ( 2 + 2 + 4

     *   trackTable       + nTracks * ( 4 + 2 + 2 )

     *   sizeTable        + nSizes * 4 )

     * ----------------------------------------------

     * vertData

     *   header         ( 2 + 2 + 4

     *   trackTable       + nTracks * ( 4 + 2 + 2 )

     *   sizeTable        + nSizes * 4 )

     * ----------------------------------------------

     */

  typedef struct  GXV_trak_DataRec_

  {

    FT_UShort  trackValueOffset_min;

    FT_UShort  trackValueOffset_max;

  } GXV_trak_DataRec, *GXV_trak_Data;

#define GXV_TRAK_DATA( FIELD )  GXV_TABLE_DATA( trak, FIELD )

  /*************************************************************************/

  /*************************************************************************/

  /*****                                                               *****/

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

  /*****                                                               *****/

  /*************************************************************************/

  /*************************************************************************/

  static void

  gxv_trak_trackTable_validate( FT_Bytes       table,

                                FT_Bytes       limit,

                                FT_UShort      nTracks,

                                GXV_Validator  valid )

  {

    FT_Bytes   p = table;

    FT_Fixed   track;

    FT_UShort  nameIndex;

    FT_UShort  offset;

    FT_UShort  i;

    GXV_NAME_ENTER( "trackTable" );

    GXV_TRAK_DATA( trackValueOffset_min ) = 0xFFFFU;

    GXV_TRAK_DATA( trackValueOffset_max ) = 0x0000;

    for ( i = 0; i < nTracks; i ++ )

    {

      GXV_LIMIT_CHECK( 4 + 2 + 2 );

      track     = FT_NEXT_LONG( p );

      nameIndex = FT_NEXT_USHORT( p );

      offset    = FT_NEXT_USHORT( p );

      if ( offset < GXV_TRAK_DATA( trackValueOffset_min ) )

        GXV_TRAK_DATA( trackValueOffset_min ) = offset;

      if ( offset > GXV_TRAK_DATA( trackValueOffset_max ) )

        GXV_TRAK_DATA( trackValueOffset_max ) = offset;

      gxv_sfntName_validate( nameIndex, 256, 32767, valid );

    }

    valid->subtable_length = p - table;

    GXV_EXIT;

  }

  static void

  gxv_trak_trackData_validate( FT_Bytes       table,

                               FT_Bytes       limit,

                               GXV_Validator  valid )

  {

    FT_Bytes   p = table;

    FT_UShort  nTracks;

    FT_UShort  nSizes;

    FT_ULong   sizeTableOffset;

    GXV_ODTECT( 4, odtect );

    GXV_ODTECT_INIT( odtect );

    GXV_NAME_ENTER( "trackData" );

    /* read the header of trackData */

    GXV_LIMIT_CHECK( 2 + 2 + 4 );

    nTracks         = FT_NEXT_USHORT( p );

    nSizes          = FT_NEXT_USHORT( p );

    sizeTableOffset = FT_NEXT_ULONG( p );

    gxv_odtect_add_range( table, p - table, "trackData header", odtect );

    /* validate trackTable */

    gxv_trak_trackTable_validate( p, limit, nTracks, valid );

    gxv_odtect_add_range( p, valid->subtable_length,

                          "trackTable", odtect );

    /* sizeTable is array of FT_Fixed, don't check contents */

    p = valid->root->base + sizeTableOffset;

    GXV_LIMIT_CHECK( nSizes * 4 );

    gxv_odtect_add_range( p, nSizes * 4, "sizeTable", odtect );

    /* validate trackValueOffet */

    p = valid->root->base + GXV_TRAK_DATA( trackValueOffset_min );

    if ( limit - p < nTracks * nSizes * 2 )

      GXV_TRACE(( "too short trackValue array\n" ));

    p = valid->root->base + GXV_TRAK_DATA( trackValueOffset_max );

    GXV_LIMIT_CHECK( nSizes * 2 );

    gxv_odtect_add_range( valid->root->base

                            + GXV_TRAK_DATA( trackValueOffset_min ),

                          GXV_TRAK_DATA( trackValueOffset_max )

                            - GXV_TRAK_DATA( trackValueOffset_min )

                            + nSizes * 2,

                          "trackValue array", odtect );

    gxv_odtect_validate( odtect, valid );

    GXV_EXIT;

  }

  /*************************************************************************/

  /*************************************************************************/

  /*****                                                               *****/

  /*****                          trak TABLE                           *****/

  /*****                                                               *****/

  /*************************************************************************/

  /*************************************************************************/

  FT_LOCAL_DEF( void )

  gxv_trak_validate( FT_Bytes      table,

                     FT_Face       face,

                     FT_Validator  ftvalid )

  {

    FT_Bytes          p = table;

    FT_Bytes          limit = 0;

    FT_Offset         table_size;

    GXV_ValidatorRec  validrec;

    GXV_Validator     valid = &validrec;

    GXV_trak_DataRec  trakrec;

    GXV_trak_Data     trak = &trakrec;

    FT_ULong   version;

    FT_UShort  format;

    FT_UShort  horizOffset;

    FT_UShort  vertOffset;

    FT_UShort  reserved;

    GXV_ODTECT( 3, odtect );

    GXV_ODTECT_INIT( odtect );

    valid->root       = ftvalid;

    valid->table_data = trak;

    valid->face       = face;

    limit      = valid->root->limit;

    table_size = limit - table;

    FT_TRACE3(( "validating `trak' table\n" ));

    GXV_INIT;

    GXV_LIMIT_CHECK( 4 + 2 + 2 + 2 + 2 );

    version     = FT_NEXT_ULONG( p );

    format      = FT_NEXT_USHORT( p );

    horizOffset = FT_NEXT_USHORT( p );

    vertOffset  = FT_NEXT_USHORT( p );

    reserved    = FT_NEXT_USHORT( p );

    GXV_TRACE(( " (version = 0x%08x)\n", version ));

    GXV_TRACE(( " (format = 0x%04x)\n", format ));

    GXV_TRACE(( " (horizOffset = 0x%04x)\n", horizOffset ));

    GXV_TRACE(( " (vertOffset = 0x%04x)\n", vertOffset ));

    GXV_TRACE(( " (reserved = 0x%04x)\n", reserved ));

    /* Version 1.0 (always:1996) */

    if ( version != 0x00010000UL )

      FT_INVALID_FORMAT;

    /* format 0 (always:1996) */

    if ( format != 0x0000 )

      FT_INVALID_FORMAT;

    GXV_32BIT_ALIGNMENT_VALIDATE( horizOffset );

    GXV_32BIT_ALIGNMENT_VALIDATE( vertOffset );

    /* Reserved Fixed Value (always) */

    if ( reserved != 0x0000 )

      FT_INVALID_DATA;

    /* validate trackData */

    if ( 0 < horizOffset )

    {

      gxv_trak_trackData_validate( table + horizOffset, limit, valid );

      gxv_odtect_add_range( table + horizOffset, valid->subtable_length,

                            "horizJustData", odtect );

    }

    if ( 0 < vertOffset )

    {

      gxv_trak_trackData_validate( table + vertOffset, limit, valid );

      gxv_odtect_add_range( table + vertOffset, valid->subtable_length,

                            "vertJustData", odtect );

    }

    gxv_odtect_validate( odtect, valid );

    FT_TRACE4(( "\n" ));

  }

/* END */