misc/libfreetype/src/gxvalid/gxvtrak.c
author nemo
Thu, 04 Apr 2013 08:10:59 -0400
changeset 8848 e9ebd63f8a03
parent 5172 88f2e05288ba
permissions -rw-r--r--
So. Some themes have objects that seem to be large natural extensions of the landscape. Masks allow maintaining that. Lemme know if it doesn't look good. If it doesn't, can still use for ice/bounce/indestructible. Indestructible bunker object for example.

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