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+/* ftglue.c: Glue code for compiling the OpenType code from
+ * FreeType 1 using only the public API of FreeType 2
+ *
+ * By David Turner, The FreeType Project (www.freetype.org)
+ *
+ * This code is explicitely put in the public domain
+ *
+ * ==========================================================================
+ *
+ * the OpenType parser codes was originally written as an extension to
+ * FreeType 1.x. As such, its source code was embedded within the library,
+ * and used many internal FreeType functions to deal with memory and
+ * stream i/o.
+ *
+ * When it was 'salvaged' for Pango and Qt, the code was "ported" to FreeType 2,
+ * which basically means that some macro tricks were performed in order to
+ * directly access FT2 _internal_ functions.
+ *
+ * these functions were never part of FT2 public API, and _did_ change between
+ * various releases. This created chaos for many users: when they upgraded the
+ * FreeType library on their system, they couldn't run Gnome anymore since
+ * Pango refused to link.
+ *
+ * Very fortunately, it's possible to completely avoid this problem because
+ * the FT_StreamRec and FT_MemoryRec structure types, which describe how
+ * memory and stream implementations interface with the rest of the font
+ * library, have always been part of the public API, and never changed.
+ *
+ * What we do thus is re-implement, within the OpenType parser, the few
+ * functions that depend on them. This only adds one or two kilobytes of
+ * code, and ensures that the parser can work with _any_ version
+ * of FreeType installed on your system. How sweet... !
+ *
+ * Note that we assume that Pango doesn't use any other internal functions
+ * from FreeType. It used to in old versions, but this should no longer
+ * be the case. (crossing my fingers).
+ *
+ * - David Turner
+ * - The FreeType Project (www.freetype.org)
+ *
+ * PS: This "glue" code is explicitely put in the public domain
+ */
+#ifndef __OPENTYPE_FTGLUE_H__
+#define __OPENTYPE_FTGLUE_H__
+
+#include "fcint.h"
+
+#include <ft2build.h>
+#include FT_FREETYPE_H
+
+FT_BEGIN_HEADER
+
+
+#define SET_ERR(c) ( (error = (c)) != 0 )
+
+#ifndef FTGLUE_API
+#define FTGLUE_API(x) extern FcPrivate x
+#endif
+
+#ifndef FTGLUE_APIDEF
+#define FTGLUE_APIDEF(x) x
+#endif
+
+/* stream macros used by the OpenType parser */
+#define FILE_Pos() ftglue_stream_pos( stream )
+#define FILE_Seek(pos) SET_ERR( ftglue_stream_seek( stream, pos ) )
+#define ACCESS_Frame(size) SET_ERR( ftglue_stream_frame_enter( stream, size ) )
+#define FORGET_Frame() ftglue_stream_frame_exit( stream )
+
+#define GET_Byte() (*stream->cursor++)
+#define GET_Short() (stream->cursor += 2, (FT_Short)( \
+ (*(((FT_Byte*)stream->cursor)-2) << 8) | \
+ *(((FT_Byte*)stream->cursor)-1) \
+ ))
+#define GET_Long() (stream->cursor += 4, (FT_Long)( \
+ (*(((FT_Byte*)stream->cursor)-4) << 24) | \
+ (*(((FT_Byte*)stream->cursor)-3) << 16) | \
+ (*(((FT_Byte*)stream->cursor)-2) << 8) | \
+ *(((FT_Byte*)stream->cursor)-1) \
+ ))
+
+#define GET_Char() ((FT_Char)GET_Byte())
+#define GET_UShort() ((FT_UShort)GET_Short())
+#define GET_ULong() ((FT_ULong)GET_Long())
+#define GET_Tag4() GET_ULong()
+
+#define FT_SET_ERROR( expression ) \
+ ( ( error = (expression) ) != 0 )
+
+FTGLUE_API( FT_Long )
+ftglue_stream_pos( FT_Stream stream );
+
+FTGLUE_API( FT_Error )
+ftglue_stream_seek( FT_Stream stream,
+ FT_Long pos );
+
+FTGLUE_API( FT_Error )
+ftglue_stream_frame_enter( FT_Stream stream,
+ FT_ULong size );
+
+FTGLUE_API( void )
+ftglue_stream_frame_exit( FT_Stream stream );
+
+FTGLUE_API( FT_Error )
+ftglue_face_goto_table( FT_Face face,
+ FT_ULong tag,
+ FT_Stream stream );
+
+FT_END_HEADER
+
+#endif /* __OPENTYPE_FTGLUE_H__ */