pfrload.c

a very goog book

/***************************************************************************/
/*                                                                         */
/*  pfrload.c                                                              */
/*                                                                         */
/*    FreeType PFR loader (body).                                          */
/*                                                                         */
/*  Copyright 2002 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 "pfrload.h"
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_STREAM_H

#include "pfrerror.h"

#undef  FT_COMPONENT
#define FT_COMPONENT  trace_pfr


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                          EXTRA ITEMS                          *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/


  FT_LOCAL_DEF( FT_Error )
  pfr_extra_items_skip( FT_Byte*  *pp,
                        FT_Byte*   limit )
  {
    return pfr_extra_items_parse( pp, limit, NULL, NULL );
  }


  FT_LOCAL_DEF( FT_Error )
  pfr_extra_items_parse( FT_Byte*       *pp,
                         FT_Byte*        limit,
                         PFR_ExtraItem   item_list,
                         FT_Pointer      item_data )
  {
    FT_Error  error = 0;
    FT_Byte*  p     = *pp;
    FT_UInt   num_items, item_type, item_size;
    

    PFR_CHECK( 1 );
    num_items = PFR_NEXT_BYTE( p );

    for ( ; num_items > 0; num_items-- )
    {
      PFR_CHECK( 2 );
      item_size = PFR_NEXT_BYTE( p );
      item_type = PFR_NEXT_BYTE( p );
      
      PFR_CHECK( item_size );

      if ( item_list )
      {      
        PFR_ExtraItem  extra = item_list;


        for ( extra = item_list; extra->parser != NULL; extra++ )
        {
          if ( extra->type == item_type )
          {
            error = extra->parser( p, p + item_size, item_data );
            if ( error ) goto Exit;
            
            break;
          }
        }
      }
      
      p += item_size;
    }

  Exit:
    *pp = p;
    return error;
    
  Too_Short:
    FT_ERROR(( "pfr_extra_items_parse: invalid extra items table\n" ));
    error = PFR_Err_Invalid_Table;
    goto Exit;
  }


  /*************************************************************************/
  /*************************************************************************/
  /*****                                                               *****/
  /*****                          PFR HEADER                           *****/
  /*****                                                               *****/
  /*************************************************************************/
  /*************************************************************************/

   static const FT_Frame_Field  pfr_header_fields[] =
   {
#undef  FT_STRUCTURE
#define FT_STRUCTURE  PFR_HeaderRec

     FT_FRAME_START( 58 ),
       FT_FRAME_ULONG ( signature ),
       FT_FRAME_USHORT( version ),
       FT_FRAME_USHORT( signature2 ),
       FT_FRAME_USHORT( header_size ),

       FT_FRAME_USHORT( log_dir_size ),
       FT_FRAME_USHORT( log_dir_offset ),

       FT_FRAME_USHORT( log_font_max_size ),
       FT_FRAME_UOFF3 ( log_font_section_size ),
       FT_FRAME_UOFF3 ( log_font_section_offset ),

       FT_FRAME_USHORT( phy_font_max_size ),
       FT_FRAME_UOFF3 ( phy_font_section_size ),
       FT_FRAME_UOFF3 ( phy_font_section_offset ),

       FT_FRAME_USHORT( gps_max_size ),
       FT_FRAME_UOFF3 ( gps_section_size ),
       FT_FRAME_UOFF3 ( gps_section_offset ),

       FT_FRAME_BYTE  ( max_blue_values ),
       FT_FRAME_BYTE  ( max_x_orus ),
       FT_FRAME_BYTE  ( max_y_orus ),

       FT_FRAME_BYTE  ( phy_font_max_size_high ),
       FT_FRAME_BYTE  ( color_flags ),

       FT_FRAME_UOFF3 ( bct_max_size ),
       FT_FRAME_UOFF3 ( bct_set_max_size ),
       FT_FRAME_UOFF3 ( phy_bct_set_max_size ),

       FT_FRAME_USHORT( num_phy_fonts ),
       FT_FRAME_BYTE  ( max_vert_stem_snap ),
       FT_FRAME_BYTE  ( max_horz_stem_snap ),
       FT_FRAME_USHORT( max_chars ),
     FT_FRAME_END
   };


  FT_LOCAL_DEF( FT_Error )
  pfr_header_load( PFR_Header  header,
                   FT_Stream   stream )
  {
    FT_Error   error;


    /* read header directly */
    if ( !FT_STREAM_SEEK( 0 )                                &&
         !FT_STREAM_READ_FIELDS( pfr_header_fields, header ) )
    {
      /* make a few adjustments to the header */
      header->phy_font_max_size +=
        (FT_UInt32)header->phy_font_max_size_high << 16;
    }

    return error;
  }


  FT_LOCAL_DEF( FT_Bool )
  pfr_header_check( PFR_Header  header )
  {
    FT_Bool  result = 1;


    /* check signature and header size */
    if ( header->signature  != 0x50465230L ||   /* "PFR0" */
         header->version     > 4           ||
         header->header_size < 58          ||
         header->signature2 != 0x0d0a      )    /* CR/LF  */
    {
      result = 0;
    }
    return  result;
  }


  /***********************************************************************/
  /***********************************************************************/
  /*****                                                             *****/
  /*****                    PFR LOGICAL FONTS                        *****/
  /*****                                                             *****/
  /***********************************************************************/
  /***********************************************************************/


  FT_LOCAL_DEF( FT_Error )
  pfr_log_font_count( FT_Stream  stream,
                      FT_UInt32  section_offset,
                      FT_UInt   *acount )
  {
    FT_Error   error;
    FT_UInt    count;
    FT_UInt    result = 0;
    

    if ( FT_STREAM_SEEK( section_offset ) || FT_READ_USHORT( count ) )
      goto Exit;
    
    result = count;
    
  Exit:
    *acount = result;
    return error;
  }                      


  FT_LOCAL_DEF( FT_Error )
  pfr_log_font_load( PFR_LogFont  log_font,
                     FT_Stream    stream,
                     FT_UInt      index,
                     FT_UInt32    section_offset,
                     FT_Bool      size_increment )
  {
    FT_UInt    num_log_fonts;
    FT_UInt    flags;
    FT_UInt32  offset;
    FT_UInt32  size;
    FT_Error   error;


    if ( FT_STREAM_SEEK( section_offset ) ||
         FT_READ_USHORT( num_log_fonts )  )
      goto Exit;

    if ( index >= num_log_fonts )
      return PFR_Err_Invalid_Argument;

    if ( FT_STREAM_SKIP( index * 5 ) ||
         FT_READ_USHORT( size )      ||
         FT_READ_UOFF3 ( offset )    )
      goto Exit;

    /* save logical font size and offset */
    log_font->size   = size;
    log_font->offset = offset;

    /* now, check the rest of the table before loading it */
    {
      FT_Byte*  p;
      FT_Byte*  limit;
      FT_UInt   local;
      

      if ( FT_STREAM_SEEK( offset ) || FT_FRAME_ENTER( size ) )
        goto Exit;

      p     = stream->cursor;
      limit = p + size;
      
      PFR_CHECK(13);
      
      log_font->matrix[0] = PFR_NEXT_LONG( p );
      log_font->matrix[1] = PFR_NEXT_LONG( p );
      log_font->matrix[2] = PFR_NEXT_LONG( p );
      log_font->matrix[3] = PFR_NEXT_LONG( p );
      
      flags = PFR_NEXT_BYTE( p );
      
      local = 0;
      if ( flags & PFR_LOG_STROKE )
      {
        local++;
        if ( flags & PFR_LOG_2BYTE_STROKE )
          local++;
          
        if ( (flags & PFR_LINE_JOIN_MASK) == PFR_LINE_JOIN_MITER )
          local += 3;
      }
      if ( flags & PFR_LOG_BOLD )
      {
        local++;
        if ( flags & PFR_LOG_2BYTE_BOLD )
          local++;
      }

      PFR_CHECK( local );

      if ( flags & PFR_LOG_STROKE )
      {
        log_font->stroke_thickness = ( flags & PFR_LOG_2BYTE_STROKE )
                                     ? PFR_NEXT_SHORT( p )
                                     : PFR_NEXT_BYTE( p );
  
        if ( ( flags & PFR_LINE_JOIN_MASK ) == PFR_LINE_JOIN_MITER )
          log_font->miter_limit = PFR_NEXT_LONG( p );
      }
  
      if ( flags & PFR_LOG_BOLD )
      {
        log_font->bold_thickness = ( flags & PFR_LOG_2BYTE_BOLD )
                                   ? PFR_NEXT_SHORT( p )
                                   : PFR_NEXT_BYTE( p );
      }
  
      if ( flags & PFR_LOG_EXTRA_ITEMS )
      {
        error = pfr_extra_items_skip( &p, limit );
        if (error) goto Fail;
      }

      PFR_CHECK(5);
      log_font->phys_size   = PFR_NEXT_USHORT( p );
      log_font->phys_offset = PFR_NEXT_ULONG( p );
      if ( size_increment )
      {
        PFR_CHECK( 1 );
        log_font->phys_size += (FT_UInt32)PFR_NEXT_BYTE( p ) << 16;
      }
    }

  Fail:
    FT_FRAME_EXIT();

  Exit:
    return error;
  
  Too_Short:
    FT_ERROR(( "pfr_log_font_load: invalid logical font table\n" ));
    error = PFR_Err_Invalid_Table;
    goto Fail;
  }


  /***********************************************************************/
  /***********************************************************************/
  /*****                                                             *****/
  /*****                    PFR PHYSICAL FONTS                       *****/
  /*****                                                             *****/
  /***********************************************************************/
  /***********************************************************************/


  /* load bitmap strikes lists */
  FT_CALLBACK_DEF( FT_Error )
  pfr_extra_item_load_bitmap_info( FT_Byte*     p,
                                   FT_Byte*     limit,
                                   PFR_PhyFont  phy_font )
  {
    FT_Memory   memory = phy_font->memory;
    PFR_Strike  strike;
    FT_UInt     flags0;
    FT_UInt     n, count, size1;
    FT_Error    error = 0;

 
    PFR_CHECK( 5 );

    p += 3;  /* skip bctSize */
    flags0 = PFR_NEXT_BYTE( p );
    count  = PFR_NEXT_BYTE( p );

    /* re-allocate when needed */
    if ( phy_font->num_strikes + count > phy_font->max_strikes )
    {
      FT_UInt  new_max = (phy_font->num_strikes + count + 3) & -4;
      
      if ( FT_RENEW_ARRAY( phy_font->strikes,
                           phy_font->num_strikes,
                           new_max ) )
        goto Exit;
        
      phy_font->max_strikes = new_max;
    }

    size1 = 1 + 1 + 1 + 2 + 2 + 1;
    if ( flags0 & PFR_STRIKE_2BYTE_XPPM )
      size1++;

    if ( flags0 & PFR_STRIKE_2BYTE_YPPM )
      size1++;

    if ( flags0 & PFR_STRIKE_3BYTE_SIZE )
      size1++;

    if ( flags0 & PFR_STRIKE_3BYTE_OFFSET )
      size1++;