path: root/tests/freetype/src/cff/cffparse.c

/***************************************************************************/
/*                                                                         */
/*  cffparse.c                                                             */
/*                                                                         */
/*    CFF token stream parser (body)                                       */
/*                                                                         */
/*  Copyright 1996-2001, 2002, 2003, 2004, 2007, 2008, 2009, 2010 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 <ft2build.h>
#include "cffparse.h"
#include FT_INTERNAL_STREAM_H
#include FT_INTERNAL_DEBUG_H

#include "cfferrs.h"
#include "cffpic.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_cffparse




  FT_LOCAL_DEF( void )
  cff_parser_init( CFF_Parser  parser,
                   FT_UInt     code,
                   void*       object,
                   FT_Library  library)
  {
    FT_MEM_ZERO( parser, sizeof ( *parser ) );

    parser->top         = parser->stack;
    parser->object_code = code;
    parser->object      = object;
    parser->library     = library;
  }


  /* read an integer */
  static FT_Long
  cff_parse_integer( FT_Byte*  start,
                     FT_Byte*  limit )
  {
    FT_Byte*  p   = start;
    FT_Int    v   = *p++;
    FT_Long   val = 0;


    if ( v == 28 )
    {
      if ( p + 2 > limit )
        goto Bad;

      val = (FT_Short)( ( (FT_Int)p[0] << 8 ) | p[1] );
      p  += 2;
    }
    else if ( v == 29 )
    {
      if ( p + 4 > limit )
        goto Bad;

      val = ( (FT_Long)p[0] << 24 ) |
            ( (FT_Long)p[1] << 16 ) |
            ( (FT_Long)p[2] <<  8 ) |
                       p[3];
      p += 4;
    }
    else if ( v < 247 )
    {
      val = v - 139;
    }
    else if ( v < 251 )
    {
      if ( p + 1 > limit )
        goto Bad;

      val = ( v - 247 ) * 256 + p[0] + 108;
      p++;
    }
    else
    {
      if ( p + 1 > limit )
        goto Bad;

      val = -( v - 251 ) * 256 - p[0] - 108;
      p++;
    }

  Exit:
    return val;

  Bad:
    val = 0;
    goto Exit;
  }


  static const FT_Long power_tens[] =
  {
    1L,
    10L,
    100L,
    1000L,
    10000L,
    100000L,
    1000000L,
    10000000L,
    100000000L,
    1000000000L
  };


  /* read a real */
  static FT_Fixed
  cff_parse_real( FT_Byte*  start,
                  FT_Byte*  limit,
                  FT_Long   power_ten,
                  FT_Long*  scaling )
  {
    FT_Byte*  p = start;
    FT_UInt   nib;
    FT_UInt   phase;

    FT_Long   result, number, exponent;
    FT_Int    sign = 0, exponent_sign = 0;
    FT_Long   exponent_add, integer_length, fraction_length;


    if ( scaling )
      *scaling = 0;

    result = 0;

    number   = 0;
    exponent = 0;

    exponent_add    = 0;
    integer_length  = 0;
    fraction_length = 0;

    /* First of all, read the integer part. */
    phase = 4;

    for (;;)
    {
      /* If we entered this iteration with phase == 4, we need to */
      /* read a new byte.  This also skips past the initial 0x1E. */
      if ( phase )
      {
        p++;

        /* Make sure we don't read past the end. */
        if ( p >= limit )
          goto Exit;
      }

      /* Get the nibble. */
      nib   = ( p[0] >> phase ) & 0xF;
      phase = 4 - phase;

      if ( nib == 0xE )
        sign = 1;
      else if ( nib > 9 )
        break;
      else
      {
        /* Increase exponent if we can't add the digit. */
        if ( number >= 0xCCCCCCCL )
          exponent_add++;
        /* Skip leading zeros. */
        else if ( nib || number )
        {
          integer_length++