ref: c0cbe87b357a4464a7d10ab8f38a65c77ea3b629
dir: /include/freetype/ftsysio.h/
#ifndef __FT_SYSTEM_IO_H__
#define __FT_SYSTEM_IO_H__
/************************************************************************/
/************************************************************************/
/***** *****/
/***** NOTE: THE CONTENT OF THIS FILE IS NOT CURRENTLY USED *****/
/***** IN NORMAL BUILDS. CONSIDER IT EXPERIMENTAL. *****/
/***** *****/
/************************************************************************/
/************************************************************************/
/********************************************************************
*
* designing custom streams is a bit different now
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
#include <ft2build.h>
#include FT_INTERNAL_OBJECT_H
FT_BEGIN_HEADER
/*@*******************************************************************
*
* @type: FT_Stream
*
* @description:
* handle to an input stream object. These are also @FT_Object handles
*/
typedef struct FT_StreamRec_* FT_Stream;
/*@*******************************************************************
*
* @type: FT_Stream_Class
*
* @description:
* opaque handle to a @FT_Stream_ClassRec class structure describing
* the methods of input streams
*/
typedef const struct FT_Stream_ClassRec_* FT_Stream_Class;
/*@*******************************************************************
*
* @functype: FT_Stream_ReadFunc
*
* @description:
* a method used to read bytes from an input stream into memory
*
* @input:
* stream :: target stream handle
* buffer :: target buffer address
* size :: number of bytes to read
*
* @return:
* number of bytes effectively read. Must be <= 'size'.
*/
typedef FT_ULong (*FT_Stream_ReadFunc)( FT_Stream stream,
FT_Byte* buffer,
FT_ULong size );
/*@*******************************************************************
*
* @functype: FT_Stream_SeekFunc
*
* @description:
* a method used to seek to a new position within a stream
*
* @input:
* stream :: target stream handle
* pos :: new read position, from start of stream
*
* @return:
* error code. 0 means success
*/
typedef FT_Error (*FT_Stream_SeekFunc)( FT_Stream stream,
FT_ULong pos );
/*@*******************************************************************
*
* @struct: FT_Stream_ClassRec
*
* @description:
* a structure used to describe an input stream class
*
* @input:
* clazz :: root @FT_ClassRec fields
* stream_read :: stream byte read method
* stream_seek :: stream seek method
*/
typedef struct FT_Stream_ClassRec_
{
FT_ClassRec clazz;
FT_Stream_ReadFunc stream_read;
FT_Stream_SeekFunc stream_seek;
} FT_Stream_ClassRec;
/* */
#define FT_STREAM_CLASS(x) ((FT_Stream_Class)(x))
#define FT_STREAM_CLASS__READ(x) FT_STREAM_CLASS(x)->stream_read
#define FT_STREAM_CLASS__SEEK(x) FT_STREAM_CLASS(x)->stream_seek;
/*@*******************************************************************
*
* @struct: FT_StreamRec
*
* @description:
* the input stream object structure. See @FT_Stream_ClassRec for
* its class descriptor
*
* @fields:
* object :: root @FT_ObjectRec fields
* size :: size of stream in bytes (0 if unknown)
* pos :: current position within stream
* base :: for memory-based streams, the address of the stream's
* first data byte in memory. NULL otherwise
*
* cursor :: the current cursor position within an input stream
* frame. Only valid within a FT_FRAME_ENTER .. FT_FRAME_EXIT
* block; NULL otherwise
*
* limit :: the current frame limit within a FT_FRAME_ENTER ..
* FT_FRAME_EXIT block. NULL otherwise
*/
typedef struct FT_StreamRec_
{
FT_ObjectRec object;
FT_ULong size;
FT_ULong pos;
const FT_Byte* base;
const FT_Byte* cursor;
const FT_Byte* limit;
} FT_StreamRec;
/* some useful macros */
#define FT_STREAM(x) ((FT_Stream)(x))
#define FT_STREAM_P(x) ((FT_Stream*)(x))
#define FT_STREAM__READ(x) FT_STREAM_CLASS__READ(FT_OBJECT__CLASS(x))
#define FT_STREAM__SEEK(x) FT_STREAM_CLASS__SEEK(FT_OBJECT__CLASS(x))
#define FT_STREAM_IS_BASED(x) ( FT_STREAM(x)->base != NULL )
/* */
/* create new memory-based stream */
FT_BASE( FT_Error ) ft_stream_new_memory( const FT_Byte* stream_base,
FT_ULong stream_size,
FT_Memory memory,
FT_Stream *astream );
FT_BASE( FT_Error ) ft_stream_new_iso( const char* pathanme,
FT_Memory memory,
FT_Stream *astream );
/* handle to default stream class implementation for a given build */
/* this is used by "FT_New_Face" */
/* */
FT_APIVAR( FT_Type ) ft_stream_default_type;
FT_END_HEADER
#endif /* __FT_SYSTEM_STREAM_H__ */