t1parse.c

Qt/Embedded是一个多平台的C++图形用户界面应用程序框架

/*******************************************************************
 *
 *  t1parse.c                                                   2.0
 *
 *    Type1 parser.
 *
 *  Copyright 1996-1998 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.
 *
 *  The Type 1 parser is in charge of the following:
 *
 *   - provide an implementation of a growing sequence of
 *     objects called a T1_Table (used to build various tables
 *     needed by the loader).
 *
 *   - opening .pfb and .pfa files to extract their top-level
 *     and private dictionaries
 *
 *   - read numbers, arrays & strings from any dictionary
 *
 *  See "t1load.c" to see how data is loaded from the font file
 *
 ******************************************************************/
 
#include <ftdebug.h>
#include <ftcalc.h>
#include <ftobjs.h>
#include <ftstream.h>
#include <t1errors.h>
#include <t1parse.h>

#undef FT_COMPONENT
#define FT_COMPONENT  trace_t1load

/*************************************************************************/
/*                                                                       */
/* <Function> T1_New_Table                                               */
/*                                                                       */
/* <Description>                                                         */
/*    Initialise a T1_Table.                                             */
/*                                                                       */
/* <Input>                                                               */
/*    table  :: address of target table                                  */
/*    count  :: table size = maximum number of elements                  */
/*    memory :: memory object to use for all subsequent reallocations    */
/*                                                                       */
/* <Return>                                                              */
/*    Error code. 0 means success                                        */
/*                                                                       */

  LOCAL_FUNC
  T1_Error  T1_New_Table( T1_Table*  table,
                          T1_Int     count,
                          FT_Memory  memory )
  {
	 T1_Error  error;

	 table->memory = memory;
	 if ( ALLOC_ARRAY( table->elements, count, T1_Byte*  ) ||
          ALLOC_ARRAY( table->lengths, count, T1_Byte* ) )
       goto Exit;

	table->max_elems = count;
    table->init      = 0xdeadbeef;
	table->num_elems = 0;
	table->block     = 0;
	table->capacity  = 0;
	table->cursor    = 0;

  Exit:
    if (error) FREE(table->elements);
      
	return error;
  }



/*************************************************************************/
/*                                                                       */
/* <Function> T1_Add_Table                                               */
/*                                                                       */
/* <Description>                                                         */
/*    Adds an object to a T1_Table, possibly growing its memory block    */
/*                                                                       */
/* <Input>                                                               */
/*    table  :: target table                                             */
/*    index  :: index of object in table                                 */
/*    object :: address of object to copy in memory                      */
/*    length :: length in bytes of source object                         */
/*                                                                       */
/* <Return>                                                              */
/*    Error code. 0 means success. An error is returned when a           */
/*    realloc failed..                                                   */
/*                                                                       */


      static void  shift_elements( T1_Table*  table, T1_Byte*  old_base )
      {
        T1_Long    delta  = table->block - old_base;
        T1_Byte**  offset = table->elements;
        T1_Byte**  limit  = offset + table->max_elems;
    
        if (delta)
          for ( ; offset < limit; offset++ )
          {
            if (offset[0])
              offset[0] += delta;
          }
      }
  
      static
      T1_Error  reallocate_t1_table( T1_Table*  table,
                                     T1_Int     new_size )
      {
        FT_Memory  memory   = table->memory;
        T1_Byte*   old_base = table->block;
        T1_Error   error;
  
        /* realloc the base block */
        if ( REALLOC( table->block, table->capacity, new_size ) )
          return error;
  
        table->capacity = new_size;
  
        /* shift all offsets when needed */
        if (old_base)
          shift_elements( table, old_base );
  
        return T1_Err_Ok;
      }



  LOCAL_FUNC
  T1_Error  T1_Add_Table( T1_Table*  table,
                          T1_Int     index,
                          void*      object,
                          T1_Int     length )
  {
	if (index < 0 || index > table->max_elems)
    {
	  FT_ERROR(( "T1.Add_Table: invalid index\n" ));
	  return T1_Err_Syntax_Error;
    }

    /* grow the base block if needed */
    if ( table->cursor + length > table->capacity )
    {
      T1_Error  error;
      T1_Int    new_size = table->capacity;

      while ( new_size < table->cursor+length )
        new_size += 1024;

      error = reallocate_t1_table( table, new_size );
      if (error) return error;
    }

    /* add the object to the base block and adjust offset */
    table->elements[ index ] = table->block + table->cursor;
    table->lengths [ index ] = length;
    MEM_Copy( table->block + table->cursor, object, length );

    table->cursor += length;
    return T1_Err_Ok;
  }


/*************************************************************************/
/*                                                                       */
/* <Function> T1_Done_Table                                              */
/*                                                                       */
/* <Description>                                                         */
/*    Finalise a T1_Table. (realloc it to its current cursor).           */
/*                                                                       */
/* <Input>                                                               */
/*    table :: target table                                              */
/*                                                                       */
/* <Note>                                                                */
/*    This function does NOT release the heap's memory block. It is up   */
/*    to the caller to clean it, or reference it in its own structures.  */
/*                                                                       */
#if 0
  LOCAL_FUNC
  void  T1_Done_Table( T1_Table*  table )
  {
    FT_Memory  memory = table->memory;
    T1_Error   error;
    T1_Byte*   old_base;

    /* should never fail, as rec.cursor <= rec.size */
    old_base = table->block;
    if (!old_base)
      return;
    
    (void)REALLOC( table->block, table->capacity, table->cursor );
    table->capacity = table->cursor;
    
    if (old_base != table->block)
      shift_elements( table, old_base );
  }
#endif

  LOCAL_FUNC
  void  T1_Release_Table( T1_Table*  table )
  {
    FT_Memory  memory = table->memory;
    
    if (table->init == 0xdeadbeef)
    {
      FREE( table->block );
      FREE( table->elements );
      FREE( table->lengths );
      table->init = 0;
    }
  }

  static
  T1_Long  t1_toint( T1_Byte* *cursor,
                     T1_Byte*  limit )
  {
    T1_Long  result = 0;
    T1_Byte* cur    = *cursor;
    T1_Byte  c, d;
    
    for (; cur < limit; cur++)
    {
      c = *cur;
      d = (T1_Byte)(c - '0');
      if (d < 10) break;
      
      if ( c=='-' )
      {
        cur++;
        break;
      }
    }
    
    if (cur < limit)
    {
      do
      {
        d = (T1_Byte)(cur[0] - '0');
        if (d >= 10)
          break;
          
        result = result*10 + d;
        cur++;
        
      } while (cur < limit);
      
      if (c == '-')
        result = -result;
    }
    
    *cursor = cur;
    return result;
  }


  static
  T1_Long  t1_tofixed( T1_Byte* *cursor,
                       T1_Byte*  limit,
                       T1_Long   power_ten )
  {
    T1_Byte* cur    = *cursor;
    T1_Long  num, divider, result;
    T1_Int   sign   = 0;
    T1_Byte  d;
    
    if (cur >= limit) return 0;
    
    /* first of all, read the integer part */
    result  = t1_toint( &cur, limit ) << 16;
    num     = 0;
    divider = 1;
    
    if (result < 0)
    {
      sign   = 1;
      result = -result;
    }
    if (cur >= limit) goto Exit;
    
    /* read decimal part, if any */
    if (*cur == '.' && cur+1 < limit)
    {
      cur++;
      
      for (;;)
      {
        d = (T1_Byte)(*cur - '0');
        if (d >= 10) break;

        if (divider < 10000000L)
        {
          num      = num*10 + d;
          divider *= 10;
        }
        cur++;
        if (cur >= limit) break;
      }
    }
    
    /* read exponent, if any */
    if ( cur+1 < limit && (*cur == 'e' || *cur == 'E'))
    {
      cur++;
      power_ten += t1_toint( &cur, limit );
    }
    
  Exit:
    /* raise to power of ten if needed */
    while (power_ten > 0)
    {
      result = result*10;
      num    = num*10;
      power_ten--;
    }
    
    while (power_ten < 0)
    {
      result  = result/10;
      divider = divider*10;
      power_ten++;
    }

    if (num)
      result += FT_DivFix( num, divider );

    if (sign)
      result = -result;
      
    *cursor = cur;
    return result;
  }


  static
  T1_Int  t1_tocoordarray( T1_Byte*  *cursor,
                           T1_Byte*   limit,
                           T1_Int     max_coords,
                           T1_Short*  coords )
  {
    T1_Byte*  cur   = *cursor;
    T1_Int    count = 0;
    T1_Byte   c, ender;
    
    if (cur >= limit) goto Exit;
    
    /* check for the beginning of an array. If not, only one number will be read */
    c     = *cur;
    ender = 0;
    
    if (c == '[')
      ender = ']';
      
    if (c == '{')
      ender = '}';
      
    if (ender)
      cur++;

    /* now, read the coordinates */
    for ( ; cur < limit; )
    {
      /* skip whitespace in front of data */
      for (;;)
      {
        c = *cur;
        if ( c != ' ' && c != '\t' ) break;
        
        cur++;
        if (cur >= limit) goto Exit;
      }
      
      if (count >= max_coords || c == ender)
        break;
      
      coords[count] = (T1_Short)(t1_tofixed(&cur,limit,0) >> 16);
      count++;
      
      if (!ender)
        break;
    }
    
  Exit:
    *cursor = cur;
    return count;
  }



  static
  T1_Int  t1_tofixedarray( T1_Byte*  *cursor,
                           T1_Byte*   limit, 
                           T1_Int     max_values,
                           T1_Fixed*  values,
                           T1_Int     power_ten )
  {
    T1_Byte*  cur   = *cursor;
    T1_Int    count = 0;
    T1_Byte   c, ender;
    
    if (cur >= limit) goto Exit;
    
    /* check for the beginning of an array. If not, only one number will be read */
    c     = *cur;
    ender = 0;
    
    if (c == '[')
      ender = ']';
      
    if (c == '{')
      ender = '}';
      
    if (ender)
      cur++;

    /* now, read the values */
    for ( ; cur < limit; )
    {
      /* skip whitespace in front of data */
      for (;;)
      {
        c = *cur;
        if ( c != ' ' && c != '\t' ) break;
        
        cur++;
        if (cur >= limit) goto Exit;
      }

      if (count >= max_values || c == ender)
        break;
      
      values[count] = t1_tofixed(&cur,limit,power_ten);
      count++;
      
      if (!ender)
        break;
    }
    
  Exit:
    *cursor = cur;
    return count;
  }


  static
  T1_String*  t1_tostring( T1_Byte* *cursor, T1_Byte* limit, FT_Memory memory )
  {
    T1_Byte*    cur = *cursor;
    T1_Int      len = 0;
    T1_Int      count;
    T1_String*  result;
    FT_Error    error;

    /* XXX : some stupid fonts have a "Notice" or "Copyright" string     */
    /*       that simply doesn't begin with an opening parenthesis, even */
    /*       though they have a closing one !!! E.g. "amuncial.pfb"      */