ttinterp.c

奇趣公司比较新的qt/emd版本

  /*    range :: The code range index.                                     */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    exec  :: The target execution context.                             */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    Does not set the Error variable.                                   */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  TT_Clear_CodeRange( TT_ExecContext  exec,
                      FT_Int          range )
  {
    FT_ASSERT( range >= 1 && range <= 3 );

    exec->codeRangeTable[range - 1].base = NULL;
    exec->codeRangeTable[range - 1].size = 0;

    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /*                   EXECUTION CONTEXT ROUTINES                          */
  /*                                                                       */
  /*************************************************************************/


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Done_Context                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Destroys a given context.                                          */
  /*                                                                       */
  /* <Input>                                                               */
  /*    exec   :: A handle to the target execution context.                */
  /*                                                                       */
  /*    memory :: A handle to the parent memory object.                    */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    Only the glyph loader and debugger should call this function.      */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  TT_Done_Context( TT_ExecContext  exec )
  {
    FT_Memory  memory = exec->memory;


    /* points zone */
    exec->maxPoints   = 0;
    exec->maxContours = 0;

    /* free stack */
    FT_FREE( exec->stack );
    exec->stackSize = 0;

    /* free call stack */
    FT_FREE( exec->callStack );
    exec->callSize = 0;
    exec->callTop  = 0;

    /* free glyph code range */
    FT_FREE( exec->glyphIns );
    exec->glyphSize = 0;

    exec->size = NULL;
    exec->face = NULL;

    FT_FREE( exec );

    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Init_Context                                                       */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Initializes a context object.                                      */
  /*                                                                       */
  /* <Input>                                                               */
  /*    memory :: A handle to the parent memory object.                    */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    exec   :: A handle to the target execution context.                */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  static FT_Error
  Init_Context( TT_ExecContext  exec,
                FT_Memory       memory )
  {
    FT_Error  error;


    FT_TRACE1(( "Init_Context: new object at 0x%08p\n", exec ));

    exec->memory   = memory;
    exec->callSize = 32;

    if ( FT_NEW_ARRAY( exec->callStack, exec->callSize ) )
      goto Fail_Memory;

    /* all values in the context are set to 0 already, but this is */
    /* here as a remainder                                         */
    exec->maxPoints   = 0;
    exec->maxContours = 0;

    exec->stackSize = 0;
    exec->glyphSize = 0;

    exec->stack     = NULL;
    exec->glyphIns  = NULL;

    exec->face = NULL;
    exec->size = NULL;

    return TT_Err_Ok;

  Fail_Memory:
    FT_ERROR(( "Init_Context: not enough memory for 0x%08lx\n",
               (FT_Long)exec ));
    TT_Done_Context( exec );

    return error;
 }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    Update_Max                                                         */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Checks the size of a buffer and reallocates it if necessary.       */
  /*                                                                       */
  /* <Input>                                                               */
  /*    memory     :: A handle to the parent memory object.                */
  /*                                                                       */
  /*    multiplier :: The size in bytes of each element in the buffer.     */
  /*                                                                       */
  /*    new_max    :: The new capacity (size) of the buffer.               */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    size       :: The address of the buffer's current size expressed   */
  /*                  in elements.                                         */
  /*                                                                       */
  /*    buff       :: The address of the buffer base pointer.              */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  static FT_Error
  Update_Max( FT_Memory  memory,
              FT_ULong*  size,
              FT_Long    multiplier,
              void*      _pbuff,
              FT_ULong   new_max )
  {
    FT_Error  error;
    void**    pbuff = (void**)_pbuff;


    if ( *size < new_max )
    {
      if ( FT_REALLOC( *pbuff, *size * multiplier, new_max * multiplier ) )
        return error;
      *size = new_max;
    }

    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Load_Context                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Prepare an execution context for glyph hinting.                    */
  /*                                                                       */
  /* <Input>                                                               */
  /*    face :: A handle to the source face object.                        */
  /*                                                                       */
  /*    size :: A handle to the source size object.                        */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    exec :: A handle to the target execution context.                  */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    Only the glyph loader and debugger should call this function.      */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  TT_Load_Context( TT_ExecContext  exec,
                   TT_Face         face,
                   TT_Size         size )
  {
    FT_Int          i;
    FT_ULong        tmp;
    TT_MaxProfile*  maxp;
    FT_Error        error;


    exec->face = face;
    maxp       = &face->max_profile;
    exec->size = size;

    if ( size )
    {
      exec->numFDefs   = size->num_function_defs;
      exec->maxFDefs   = size->max_function_defs;
      exec->numIDefs   = size->num_instruction_defs;
      exec->maxIDefs   = size->max_instruction_defs;
      exec->FDefs      = size->function_defs;
      exec->IDefs      = size->instruction_defs;
      exec->tt_metrics = size->ttmetrics;
      exec->metrics    = size->metrics;

      exec->maxFunc    = size->max_func;
      exec->maxIns     = size->max_ins;

      for ( i = 0; i < TT_MAX_CODE_RANGES; i++ )
        exec->codeRangeTable[i] = size->codeRangeTable[i];

      /* set graphics state */
      exec->GS = size->GS;

      exec->cvtSize = size->cvt_size;
      exec->cvt     = size->cvt;

      exec->storeSize = size->storage_size;
      exec->storage   = size->storage;

      exec->twilight  = size->twilight;
    }

    /* XXX: We reserve a little more elements on the stack to deal safely */
    /*      with broken fonts like arialbs, courbs, timesbs, etc.         */
    tmp = exec->stackSize;
    error = Update_Max( exec->memory,
                        &tmp,
                        sizeof ( FT_F26Dot6 ),
                        (void*)&exec->stack,
                        maxp->maxStackElements + 32 );
    exec->stackSize = (FT_UInt)tmp;
    if ( error )
      return error;

    tmp = exec->glyphSize;
    error = Update_Max( exec->memory,
                        &tmp,
                        sizeof ( FT_Byte ),
                        (void*)&exec->glyphIns,
                        maxp->maxSizeOfInstructions );
    exec->glyphSize = (FT_UShort)tmp;
    if ( error )
      return error;

    exec->pts.n_points   = 0;
    exec->pts.n_contours = 0;

    exec->instruction_trap = FALSE;

    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Save_Context                                                    */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Saves the code ranges in a `size' object.                          */
  /*                                                                       */
  /* <Input>                                                               */
  /*    exec :: A handle to the source execution context.                  */
  /*                                                                       */
  /* <InOut>                                                               */
  /*    size :: A handle to the target size object.                        */
  /*                                                                       */
  /* <Return>                                                              */
  /*    FreeType error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */
  /*    Only the glyph loader and debugger should call this function.      */
  /*                                                                       */
  FT_LOCAL_DEF( FT_Error )
  TT_Save_Context( TT_ExecContext  exec,
                   TT_Size         size )
  {
    FT_Int  i;


    /* XXXX: Will probably disappear soon with all the code range */
    /*       management, which is now rather obsolete.            */
    /*                                                            */
    size->num_function_defs    = exec->numFDefs;
    size->num_instruction_defs = exec->numIDefs;

    size->max_func = exec->maxFunc;
    size->max_ins  = exec->maxIns;

    for ( i = 0; i < TT_MAX_CODE_RANGES; i++ )
      size->codeRangeTable[i] = exec->codeRangeTable[i];

    return TT_Err_Ok;
  }


  /*************************************************************************/
  /*                                                                       */
  /* <Function>                                                            */
  /*    TT_Run_Context                                                     */
  /*                                                                       */
  /* <Description>                                                         */
  /*    Executes one or more instructions in the execution context.        */
  /*                                                                       */
  /* <Input>                                                               */
  /*    debug :: A Boolean flag.  If set, the function sets some internal  */
  /*             variables and returns immediately, otherwise TT_RunIns()  */
  /*             is called.                                                */
  /*                                                                       */
  /*             This is commented out currently.                          */
  /*                                                                       */
  /* <Input>                                                               */
  /*    exec  :: A handle to the target execution context.                 */
  /*                                                                       */
  /* <Return>                                                              */
  /*    TrueTyoe error code.  0 means success.                             */
  /*                                                                       */
  /* <Note>                                                                */