misc/libfreetype/src/cff/cffparse.c
author belphegorr <szabibibi@gmail.com>
Mon, 23 Jul 2012 19:15:59 +0300
changeset 7263 644eabbc9218
parent 5172 88f2e05288ba
permissions -rw-r--r--
Added a new function: AddNewEvent, which only adds an event to the list if it doesn't already exist. Kept the old one as it might me useful to be able to add an event more than once.

/***************************************************************************/
/*                                                                         */
/*  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++;
          number = number * 10 + nib;
        }
      }
    }

    /* Read fraction part, if any. */
    if ( nib == 0xa )
      for (;;)
      {
        /* If we entered this iteration with phase == 4, we need */
        /* to read a new byte.                                   */
        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 >= 10 )
          break;

        /* Skip leading zeros if possible. */
        if ( !nib && !number )
          exponent_add--;
        /* Only add digit if we don't overflow. */
        else if ( number < 0xCCCCCCCL && fraction_length < 9 )
        {
          fraction_length++;
          number = number * 10 + nib;
        }
      }

    /* Read exponent, if any. */
    if ( nib == 12 )
    {
      exponent_sign = 1;
      nib           = 11;
    }

    if ( nib == 11 )
    {
      for (;;)
      {
        /* If we entered this iteration with phase == 4, */
        /* we need to read a new byte.                   */
        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 >= 10 )
          break;

        exponent = exponent * 10 + nib;

        /* Arbitrarily limit exponent. */
        if ( exponent > 1000 )
          goto Exit;
      }

      if ( exponent_sign )
        exponent = -exponent;
    }

    /* We don't check `power_ten' and `exponent_add'. */
    exponent += power_ten + exponent_add;

    if ( scaling )
    {
      /* Only use `fraction_length'. */
      fraction_length += integer_length;
      exponent        += integer_length;

      if ( fraction_length <= 5 )
      {
        if ( number > 0x7FFFL )
        {
          result   = FT_DivFix( number, 10 );
          *scaling = exponent - fraction_length + 1;
        }
        else
        {
          if ( exponent > 0 )
          {
            FT_Long  new_fraction_length, shift;


            /* Make `scaling' as small as possible. */
            new_fraction_length = FT_MIN( exponent, 5 );
            exponent           -= new_fraction_length;
            shift               = new_fraction_length - fraction_length;

            number *= power_tens[shift];
            if ( number > 0x7FFFL )
            {
              number   /= 10;
              exponent += 1;
            }
          }
          else
            exponent -= fraction_length;

          result   = number << 16;
          *scaling = exponent;
        }
      }
      else
      {
        if ( ( number / power_tens[fraction_length - 5] ) > 0x7FFFL )
        {
          result   = FT_DivFix( number, power_tens[fraction_length - 4] );
          *scaling = exponent - 4;
        }
        else
        {
          result   = FT_DivFix( number, power_tens[fraction_length - 5] );
          *scaling = exponent - 5;
        }
      }
    }
    else
    {
      integer_length  += exponent;
      fraction_length -= exponent;

      /* Check for overflow and underflow. */
      if ( FT_ABS( integer_length ) > 5 )
        goto Exit;

      /* Remove non-significant digits. */
      if ( integer_length < 0 )
      {
        number          /= power_tens[-integer_length];
        fraction_length += integer_length;
      }

      /* this can only happen if exponent was non-zero */
      if ( fraction_length == 10 )
      {
        number          /= 10;
        fraction_length -= 1;
      }

      /* Convert into 16.16 format. */
      if ( fraction_length > 0 )
      {
        if ( ( number / power_tens[fraction_length] ) > 0x7FFFL )
          goto Exit;

        result = FT_DivFix( number, power_tens[fraction_length] );
      }
      else
      {
        number *= power_tens[-fraction_length];

        if ( number > 0x7FFFL )
          goto Exit;

        result = number << 16;
      }
    }

    if ( sign )
      result = -result;

  Exit:
    return result;
  }


  /* read a number, either integer or real */
  static FT_Long
  cff_parse_num( FT_Byte**  d )
  {
    return **d == 30 ? ( cff_parse_real( d[0], d[1], 0, NULL ) >> 16 )
                     :   cff_parse_integer( d[0], d[1] );
  }


  /* read a floating point number, either integer or real */
  static FT_Fixed
  cff_parse_fixed( FT_Byte**  d )
  {
    return **d == 30 ? cff_parse_real( d[0], d[1], 0, NULL )
                     : cff_parse_integer( d[0], d[1] ) << 16;
  }


  /* read a floating point number, either integer or real, */
  /* but return `10^scaling' times the number read in      */
  static FT_Fixed
  cff_parse_fixed_scaled( FT_Byte**  d,
                          FT_Long    scaling )
  {
    return **d == 30 ? cff_parse_real( d[0], d[1], scaling, NULL )
                     : ( cff_parse_integer( d[0], d[1] ) *
                           power_tens[scaling] ) << 16;
  }


  /* read a floating point number, either integer or real,     */
  /* and return it as precise as possible -- `scaling' returns */
  /* the scaling factor (as a power of 10)                     */
  static FT_Fixed
  cff_parse_fixed_dynamic( FT_Byte**  d,
                           FT_Long*   scaling )
  {
    FT_ASSERT( scaling );

    if ( **d == 30 )
      return cff_parse_real( d[0], d[1], 0, scaling );
    else
    {
      FT_Long  number;
      FT_Int   integer_length;


      number = cff_parse_integer( d[0], d[1] );

      if ( number > 0x7FFFL )
      {
        for ( integer_length = 5; integer_length < 10; integer_length++ )
          if ( number < power_tens[integer_length] )
            break;

        if ( ( number / power_tens[integer_length - 5] ) > 0x7FFFL )
        {
          *scaling = integer_length - 4;
          return FT_DivFix( number, power_tens[integer_length - 4] );
        }
        else
        {
          *scaling = integer_length - 5;
          return FT_DivFix( number, power_tens[integer_length - 5] );
        }
      }
      else
      {
        *scaling = 0;
        return number << 16;
      }
    }
  }


  static FT_Error
  cff_parse_font_matrix( CFF_Parser  parser )
  {
    CFF_FontRecDict  dict   = (CFF_FontRecDict)parser->object;
    FT_Matrix*       matrix = &dict->font_matrix;
    FT_Vector*       offset = &dict->font_offset;
    FT_ULong*        upm    = &dict->units_per_em;
    FT_Byte**        data   = parser->stack;
    FT_Error         error  = CFF_Err_Stack_Underflow;


    if ( parser->top >= parser->stack + 6 )
    {
      FT_Long  scaling;


      error = CFF_Err_Ok;

      /* We expect a well-formed font matrix, this is, the matrix elements */
      /* `xx' and `yy' are of approximately the same magnitude.  To avoid  */
      /* loss of precision, we use the magnitude of element `xx' to scale  */
      /* all other elements.  The scaling factor is then contained in the  */
      /* `units_per_em' value.                                             */

      matrix->xx = cff_parse_fixed_dynamic( data++, &scaling );

      scaling = -scaling;

      if ( scaling < 0 || scaling > 9 )
      {
        /* Return default matrix in case of unlikely values. */
        matrix->xx = 0x10000L;
        matrix->yx = 0;
        matrix->yx = 0;
        matrix->yy = 0x10000L;
        offset->x  = 0;
        offset->y  = 0;
        *upm       = 1;

        goto Exit;
      }

      matrix->yx = cff_parse_fixed_scaled( data++, scaling );
      matrix->xy = cff_parse_fixed_scaled( data++, scaling );
      matrix->yy = cff_parse_fixed_scaled( data++, scaling );
      offset->x  = cff_parse_fixed_scaled( data++, scaling );
      offset->y  = cff_parse_fixed_scaled( data,   scaling );

      *upm = power_tens[scaling];
    }

  Exit:
    return error;
  }


  static FT_Error
  cff_parse_font_bbox( CFF_Parser  parser )
  {
    CFF_FontRecDict  dict = (CFF_FontRecDict)parser->object;
    FT_BBox*         bbox = &dict->font_bbox;
    FT_Byte**        data = parser->stack;
    FT_Error         error;


    error = CFF_Err_Stack_Underflow;

    if ( parser->top >= parser->stack + 4 )
    {
      bbox->xMin = FT_RoundFix( cff_parse_fixed( data++ ) );
      bbox->yMin = FT_RoundFix( cff_parse_fixed( data++ ) );
      bbox->xMax = FT_RoundFix( cff_parse_fixed( data++ ) );
      bbox->yMax = FT_RoundFix( cff_parse_fixed( data   ) );
      error = CFF_Err_Ok;
    }

    return error;
  }


  static FT_Error
  cff_parse_private_dict( CFF_Parser  parser )
  {
    CFF_FontRecDict  dict = (CFF_FontRecDict)parser->object;
    FT_Byte**        data = parser->stack;
    FT_Error         error;


    error = CFF_Err_Stack_Underflow;

    if ( parser->top >= parser->stack + 2 )
    {
      dict->private_size   = cff_parse_num( data++ );
      dict->private_offset = cff_parse_num( data   );
      error = CFF_Err_Ok;
    }

    return error;
  }


  static FT_Error
  cff_parse_cid_ros( CFF_Parser  parser )
  {
    CFF_FontRecDict  dict = (CFF_FontRecDict)parser->object;
    FT_Byte**        data = parser->stack;
    FT_Error         error;


    error = CFF_Err_Stack_Underflow;

    if ( parser->top >= parser->stack + 3 )
    {
      dict->cid_registry   = (FT_UInt)cff_parse_num ( data++ );
      dict->cid_ordering   = (FT_UInt)cff_parse_num ( data++ );
      if ( **data == 30 )
        FT_TRACE1(( "cff_parse_cid_ros: real supplement is rounded\n" ));
      dict->cid_supplement = cff_parse_num( data );
      if ( dict->cid_supplement < 0 )
        FT_TRACE1(( "cff_parse_cid_ros: negative supplement %d is found\n",
                   dict->cid_supplement ));
      error = CFF_Err_Ok;
    }

    return error;
  }


#define CFF_FIELD_NUM( code, name ) \
          CFF_FIELD( code, name, cff_kind_num )
#define CFF_FIELD_FIXED( code, name ) \
          CFF_FIELD( code, name, cff_kind_fixed )
#define CFF_FIELD_FIXED_1000( code, name ) \
          CFF_FIELD( code, name, cff_kind_fixed_thousand )
#define CFF_FIELD_STRING( code, name ) \
          CFF_FIELD( code, name, cff_kind_string )
#define CFF_FIELD_BOOL( code, name ) \
          CFF_FIELD( code, name, cff_kind_bool )
#define CFF_FIELD_DELTA( code, name, max ) \
          CFF_FIELD( code, name, cff_kind_delta )

#define CFFCODE_TOPDICT  0x1000
#define CFFCODE_PRIVATE  0x2000

#ifndef FT_CONFIG_OPTION_PIC

#define CFF_FIELD_CALLBACK( code, name ) \
          {                              \
            cff_kind_callback,           \
            code | CFFCODE,              \
            0, 0,                        \
            cff_parse_ ## name,          \
            0, 0                         \
          },

#undef  CFF_FIELD
#define CFF_FIELD( code, name, kind ) \
          {                          \
            kind,                    \
            code | CFFCODE,          \
            FT_FIELD_OFFSET( name ), \
            FT_FIELD_SIZE( name ),   \
            0, 0, 0                  \
          },

#undef  CFF_FIELD_DELTA
#define CFF_FIELD_DELTA( code, name, max ) \
        {                                  \
          cff_kind_delta,                  \
          code | CFFCODE,                  \
          FT_FIELD_OFFSET( name ),         \
          FT_FIELD_SIZE_DELTA( name ),     \
          0,                               \
          max,                             \
          FT_FIELD_OFFSET( num_ ## name )  \
        },

  static const CFF_Field_Handler  cff_field_handlers[] =
  {

#include "cfftoken.h"

    { 0, 0, 0, 0, 0, 0, 0 }
  };


#else /* FT_CONFIG_OPTION_PIC */

  void FT_Destroy_Class_cff_field_handlers(FT_Library library, CFF_Field_Handler* clazz)
  {
    FT_Memory memory = library->memory;
    if ( clazz )
      FT_FREE( clazz );
  }

  FT_Error FT_Create_Class_cff_field_handlers(FT_Library library, CFF_Field_Handler** output_class)
  {
    CFF_Field_Handler*  clazz;
    FT_Error          error;
    FT_Memory memory = library->memory;
    int i=0;

#undef CFF_FIELD
#undef CFF_FIELD_DELTA
#undef CFF_FIELD_CALLBACK
#define CFF_FIELD_CALLBACK( code, name ) i++;
#define CFF_FIELD( code, name, kind ) i++;
#define CFF_FIELD_DELTA( code, name, max ) i++;

#include "cfftoken.h"
    i++;/*{ 0, 0, 0, 0, 0, 0, 0 }*/

    if ( FT_ALLOC( clazz, sizeof(CFF_Field_Handler)*i ) )
      return error;

    i=0;
#undef CFF_FIELD
#undef CFF_FIELD_DELTA
#undef CFF_FIELD_CALLBACK

#define CFF_FIELD_CALLBACK( code_, name_ )                                   \
    clazz[i].kind = cff_kind_callback;                                       \
    clazz[i].code = code_ | CFFCODE;                                         \
    clazz[i].offset = 0;                                                     \
    clazz[i].size = 0;                                                       \
    clazz[i].reader = cff_parse_ ## name_;                                   \
    clazz[i].array_max = 0;                                                  \
    clazz[i].count_offset = 0;                                               \
    i++;

#undef  CFF_FIELD
#define CFF_FIELD( code_, name_, kind_ )                                     \
    clazz[i].kind = kind_;                                                   \
    clazz[i].code = code_ | CFFCODE;                                         \
    clazz[i].offset = FT_FIELD_OFFSET( name_ );                              \
    clazz[i].size = FT_FIELD_SIZE( name_ );                                  \
    clazz[i].reader = 0;                                                     \
    clazz[i].array_max = 0;                                                  \
    clazz[i].count_offset = 0;                                               \
    i++;                                                                     \

#undef  CFF_FIELD_DELTA
#define CFF_FIELD_DELTA( code_, name_, max_ )                                \
    clazz[i].kind = cff_kind_delta;                                          \
    clazz[i].code = code_ | CFFCODE;                                         \
    clazz[i].offset = FT_FIELD_OFFSET( name_ );                              \
    clazz[i].size = FT_FIELD_SIZE_DELTA( name_ );                            \
    clazz[i].reader = 0;                                                     \
    clazz[i].array_max = max_;                                               \
    clazz[i].count_offset = FT_FIELD_OFFSET( num_ ## name_ );                \
    i++;

#include "cfftoken.h"

    clazz[i].kind = 0;
    clazz[i].code = 0;
    clazz[i].offset = 0;
    clazz[i].size = 0;
    clazz[i].reader = 0;
    clazz[i].array_max = 0;
    clazz[i].count_offset = 0;

    *output_class = clazz;
    return CFF_Err_Ok;
  }


#endif /* FT_CONFIG_OPTION_PIC */


  FT_LOCAL_DEF( FT_Error )
  cff_parser_run( CFF_Parser  parser,
                  FT_Byte*    start,
                  FT_Byte*    limit )
  {
    FT_Byte*    p       = start;
    FT_Error    error   = CFF_Err_Ok;
    FT_Library  library = parser->library;
    FT_UNUSED(library);


    parser->top    = parser->stack;
    parser->start  = start;
    parser->limit  = limit;
    parser->cursor = start;

    while ( p < limit )
    {
      FT_UInt  v = *p;


      if ( v >= 27 && v != 31 )
      {
        /* it's a number; we will push its position on the stack */
        if ( parser->top - parser->stack >= CFF_MAX_STACK_DEPTH )
          goto Stack_Overflow;

        *parser->top ++ = p;

        /* now, skip it */
        if ( v == 30 )
        {
          /* skip real number */
          p++;
          for (;;)
          {
            /* An unterminated floating point number at the */
            /* end of a dictionary is invalid but harmless. */
            if ( p >= limit )
              goto Exit;
            v = p[0] >> 4;
            if ( v == 15 )
              break;
            v = p[0] & 0xF;
            if ( v == 15 )
              break;
            p++;
          }
        }
        else if ( v == 28 )
          p += 2;
        else if ( v == 29 )
          p += 4;
        else if ( v > 246 )
          p += 1;
      }
      else
      {
        /* This is not a number, hence it's an operator.  Compute its code */
        /* and look for it in our current list.                            */

        FT_UInt                   code;
        FT_UInt                   num_args = (FT_UInt)
                                             ( parser->top - parser->stack );
        const CFF_Field_Handler*  field;


        *parser->top = p;
        code = v;
        if ( v == 12 )
        {
          /* two byte operator */
          p++;
          if ( p >= limit )
            goto Syntax_Error;

          code = 0x100 | p[0];
        }
        code = code | parser->object_code;

        for ( field = FT_CFF_FIELD_HANDLERS_GET; field->kind; field++ )
        {
          if ( field->code == (FT_Int)code )
          {
            /* we found our field's handler; read it */
            FT_Long   val;
            FT_Byte*  q = (FT_Byte*)parser->object + field->offset;


            /* check that we have enough arguments -- except for */
            /* delta encoded arrays, which can be empty          */
            if ( field->kind != cff_kind_delta && num_args < 1 )
              goto Stack_Underflow;

            switch ( field->kind )
            {
            case cff_kind_bool:
            case cff_kind_string:
            case cff_kind_num:
              val = cff_parse_num( parser->stack );
              goto Store_Number;

            case cff_kind_fixed:
              val = cff_parse_fixed( parser->stack );
              goto Store_Number;

            case cff_kind_fixed_thousand:
              val = cff_parse_fixed_scaled( parser->stack, 3 );

            Store_Number:
              switch ( field->size )
              {
              case (8 / FT_CHAR_BIT):
                *(FT_Byte*)q = (FT_Byte)val;
                break;

              case (16 / FT_CHAR_BIT):
                *(FT_Short*)q = (FT_Short)val;
                break;

              case (32 / FT_CHAR_BIT):
                *(FT_Int32*)q = (FT_Int)val;
                break;

              default:  /* for 64-bit systems */
                *(FT_Long*)q = val;
              }
              break;

            case cff_kind_delta:
              {
                FT_Byte*   qcount = (FT_Byte*)parser->object +
                                      field->count_offset;

                FT_Byte**  data = parser->stack;


                if ( num_args > field->array_max )
                  num_args = field->array_max;

                /* store count */
                *qcount = (FT_Byte)num_args;

                val = 0;
                while ( num_args > 0 )
                {
                  val += cff_parse_num( data++ );
                  switch ( field->size )
                  {
                  case (8 / FT_CHAR_BIT):
                    *(FT_Byte*)q = (FT_Byte)val;
                    break;

                  case (16 / FT_CHAR_BIT):
                    *(FT_Short*)q = (FT_Short)val;
                    break;

                  case (32 / FT_CHAR_BIT):
                    *(FT_Int32*)q = (FT_Int)val;
                    break;

                  default:  /* for 64-bit systems */
                    *(FT_Long*)q = val;
                  }

                  q += field->size;
                  num_args--;
                }
              }
              break;

            default:  /* callback */
              error = field->reader( parser );
              if ( error )
                goto Exit;
            }
            goto Found;
          }
        }

        /* this is an unknown operator, or it is unsupported; */
        /* we will ignore it for now.                         */

      Found:
        /* clear stack */
        parser->top = parser->stack;
      }
      p++;
    }

  Exit:
    return error;

  Stack_Overflow:
    error = CFF_Err_Invalid_Argument;
    goto Exit;

  Stack_Underflow:
    error = CFF_Err_Invalid_Argument;
    goto Exit;

  Syntax_Error:
    error = CFF_Err_Invalid_Argument;
    goto Exit;
  }


/* END */