ref: 2fa573c1b038a32b7c6f5c76477f9b66a47cc425
parent: 83dba0e9ec073d26e1a6febe62cc12e9dca2583c
author: Nikhil Ramakrishnan <[email protected]>
date: Tue Jun 11 20:21:20 EDT 2019
[sfnt] Read WOFF 2 header. Check for WOFF2 tag, call `woff2_open_font', and implement it to read header according to specification. * include/freetype/internal/fttrace.h: Add `sfwoff2.c'. * src/sfnt/rules.mk (SFNT_DRV_SRC): Add `sfwoff2.c'. * src/sfnt/sfnt.c: Include `sfwoff2.c'. * src/sfnt/sfobjs.c (sfnt_open_font): Check for `wOF2' tag and call `woff2_open_font'. * src/sfnt/sfwoff2.c, src/sfnt/sfwoff2.h: New files.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,23 @@
2019-08-27 Nikhil Ramakrishnan <[email protected]>
+ [sfnt] Read WOFF 2 header.
+
+ Check for WOFF2 tag, call `woff2_open_font', and implement it to read
+ header according to specification.
+
+ * include/freetype/internal/fttrace.h: Add `sfwoff2.c'.
+
+ * src/sfnt/rules.mk (SFNT_DRV_SRC): Add `sfwoff2.c'.
+
+ * src/sfnt/sfnt.c: Include `sfwoff2.c'.
+
+ * src/sfnt/sfobjs.c (sfnt_open_font): Check for `wOF2' tag and call
+ `woff2_open_font'.
+
+ * src/sfnt/sfwoff2.c, src/sfnt/sfwoff2.h: New files.
+
+2019-08-27 Nikhil Ramakrishnan <[email protected]>
+
Add structures for WOFF2.
Add structures and macro for WOFF 2 header and table directory.
--- a/include/freetype/internal/fttrace.h
+++ b/include/freetype/internal/fttrace.h
@@ -49,6 +49,7 @@
FT_TRACE_DEF( sfdriver ) /* SFNT font driver (sfdriver.c) */
FT_TRACE_DEF( sfobjs ) /* SFNT object handler (sfobjs.c) */
FT_TRACE_DEF( sfwoff ) /* WOFF format handler (sfwoff.c) */
+FT_TRACE_DEF( sfwoff2 ) /* WOFF2 format handler (sfwoff2.c) */
FT_TRACE_DEF( ttbdf ) /* TrueType embedded BDF (ttbdf.c) */
FT_TRACE_DEF( ttcmap ) /* charmap handler (ttcmap.c) */
FT_TRACE_DEF( ttcolr ) /* glyph layer table (ttcolr.c) */
--- a/src/sfnt/rules.mk
+++ b/src/sfnt/rules.mk
@@ -32,6 +32,7 @@
$(SFNT_DIR)/sfdriver.c \
$(SFNT_DIR)/sfobjs.c \
$(SFNT_DIR)/sfwoff.c \
+ $(SFNT_DIR)/sfwoff2.c \
$(SFNT_DIR)/ttbdf.c \
$(SFNT_DIR)/ttcmap.c \
$(SFNT_DIR)/ttcolr.c \
--- a/src/sfnt/sfnt.c
+++ b/src/sfnt/sfnt.c
@@ -23,6 +23,7 @@
#include "sfdriver.c"
#include "sfobjs.c"
#include "sfwoff.c"
+#include "sfwoff2.c"
#include "ttbdf.c"
#include "ttcmap.c"
#include "ttcolr.c"
--- a/src/sfnt/sfobjs.c
+++ b/src/sfnt/sfobjs.c
@@ -22,6 +22,7 @@
#include "ttcmap.h"
#include "ttkern.h"
#include "sfwoff.h"
+#include "sfwoff2.h"
#include FT_INTERNAL_SFNT_H
#include FT_INTERNAL_DEBUG_H
#include FT_TRUETYPE_IDS_H
@@ -377,6 +378,22 @@
return error;
error = woff_open_font( stream, face );
+ if ( error )
+ return error;
+
+ /* Swap out stream and retry! */
+ stream = face->root.stream;
+ goto retry;
+ }
+
+ if ( tag == TTAG_wOF2 )
+ {+ FT_TRACE2(( "sfnt_open_font: file is a WOFF2; synthesizing SFNT\n" ));
+
+ if ( FT_STREAM_SEEK( offset ) )
+ return error;
+
+ error = woff2_open_font( stream, face );
if ( error )
return error;
--- /dev/null
+++ b/src/sfnt/sfwoff2.c
@@ -1,0 +1,169 @@
+/****************************************************************************
+ *
+ * sfwoff2.c
+ *
+ * WOFF2 format management (base).
+ *
+ * Copyright (C) 2019 by
+ * Nikhil Ramakrishnan, 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 "sfwoff2.h"
+#include FT_TRUETYPE_TAGS_H
+#include FT_INTERNAL_DEBUG_H
+#include FT_INTERNAL_STREAM_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 sfwoff2
+
+
+ static FT_Error
+ ReadBase128( FT_Stream stream,
+ FT_ULong* value )
+ {+ FT_ULong result = 0;
+ FT_Int i;
+ FT_Byte code;
+ FT_Byte* p = stream->cursor;
+
+ for ( i = 0; i < 5; ++i ) {+ code = 0;
+ code = FT_NEXT_BYTE( p );
+
+ /* Leading zeros are invalid. */
+ if ( i == 0 && code == 0x80 ) {+ return FT_THROW( Invalid_Table );
+ }
+
+ /* If any of top seven bits are set then we're about to overflow. */
+ if ( result & 0xfe000000 ){+ return FT_THROW( Invalid_Table );
+ }
+
+ result = ( result << 7 ) | ( code & 0x7f );
+
+ /* Spin until most significant bit of data byte is false. */
+ if ( (code & 0x80) == 0 ) {+ *value = result;
+ return FT_Err_Ok;
+ }
+ }
+ /* Make sure not to exceed the size bound. */
+ return FT_THROW( Invalid_Table );
+ }
+
+
+ /* Replace `face->root.stream' with a stream containing the extracted */
+ /* SFNT of a WOFF2 font. */
+
+ FT_LOCAL_DEF( FT_Error )
+ woff2_open_font( FT_Stream stream,
+ TT_Face face )
+ {+ FT_Memory memory = stream->memory;
+ FT_Error error = FT_Err_Ok;
+ FT_Byte* p = stream->cursor;
+ FT_Byte* limit = stream->limit;
+
+ WOFF2_HeaderRec woff2;
+ WOFF2_Table tables = NULL;
+ WOFF2_Table* indices = NULL;
+
+ static const FT_Frame_Field woff2_header_fields[] =
+ {+#undef FT_STRUCTURE
+#define FT_STRUCTURE WOFF2_HeaderRec
+
+ FT_FRAME_START( 48 ),
+ FT_FRAME_ULONG ( signature ),
+ FT_FRAME_ULONG ( flavor ),
+ FT_FRAME_ULONG ( length ),
+ FT_FRAME_USHORT( num_tables ),
+ FT_FRAME_SKIP_BYTES( 2 + 4 ),
+ FT_FRAME_ULONG ( totalCompressedSize ),
+ FT_FRAME_SKIP_BYTES( 2 * 2 ),
+ FT_FRAME_ULONG ( metaOffset ),
+ FT_FRAME_ULONG ( metaLength ),
+ FT_FRAME_ULONG ( metaOrigLength ),
+ FT_FRAME_ULONG ( privOffset ),
+ FT_FRAME_ULONG ( privLength ),
+ FT_FRAME_END
+ };
+
+ FT_UNUSED( p );
+ FT_UNUSED( limit );
+ FT_UNUSED( tables );
+ FT_UNUSED( indices );
+ FT_UNUSED( memory );
+
+ /* DEBUG - Remove later */
+ FT_TRACE2(("woff2_open_font: Received Data.\n"));+
+ FT_ASSERT( stream == face->root.stream );
+ FT_ASSERT( FT_STREAM_POS() == 0 );
+
+ /* Read WOFF2 Header. */
+ if ( FT_STREAM_READ_FIELDS( woff2_header_fields, &woff2 ) )
+ return error;
+
+ /* DEBUG - Remove later. */
+ FT_TRACE2(("signature -> 0x%X\n", woff2.signature));+ FT_TRACE2(("flavor -> 0x%X\n", woff2.flavor));+ FT_TRACE2(("length -> %lu\n", woff2.length));+ FT_TRACE2(("num_tables -> %hu\n", woff2.num_tables));+ FT_TRACE2(("metaOffset -> %hu\n", woff2.metaOffset));+ FT_TRACE2(("metaLength -> %hu\n", woff2.metaLength));+ FT_TRACE2(("privOffset -> %hu\n", woff2.privOffset));+ FT_TRACE2(("privLength -> %hu\n", woff2.privLength));+
+ /* Make sure we don't recurse back here. */
+ if ( woff2.flavor == TTAG_wOF2 )
+ return FT_THROW( Invalid_Table );
+
+ /* Miscellaneous checks. */
+ if ( woff2.length != stream->size ||
+ woff2.num_tables == 0 ||
+ 48 + woff2.num_tables * 20UL >= woff2.length ||
+ ( woff2.metaOffset == 0 && ( woff2.metaLength != 0 ||
+ woff2.metaOrigLength != 0 ) ) ||
+ ( woff2.metaLength != 0 && woff2.metaOrigLength == 0 ) ||
+ ( woff2.metaOffset >= woff2.length ) ||
+ ( woff2.length - woff2.metaOffset < woff2.metaLength ) ||
+ ( woff2.privOffset == 0 && woff2.privLength != 0 ) ||
+ ( woff2.privOffset >= woff2.length ) ||
+ ( woff2.length - woff2.privOffset < woff2.privLength ) )
+ {+ FT_ERROR(( "woff_font_open: invalid WOFF2 header\n" ));
+ return FT_THROW( Invalid_Table );
+ }
+ /* DEBUG - Remove later. */
+ else{+ FT_TRACE2(("WOFF2 Header is valid.\n"));+ }
+
+ /* TODO Read table directory. */
+
+ error = FT_THROW( Unimplemented_Feature );
+ goto Exit;
+
+ Exit:
+ return error;
+ }
+
+
+/* END */
--- /dev/null
+++ b/src/sfnt/sfwoff2.h
@@ -1,0 +1,41 @@
+/****************************************************************************
+ *
+ * sfwoff2.h
+ *
+ * WOFFF2 format management (specification).
+ *
+ * Copyright (C) 2019 by
+ * Nikhil Ramakrishnan, 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.
+ *
+ */
+
+
+#ifndef SFWOFF2_H_
+#define SFWOFF2_H_
+
+
+#include <ft2build.h>
+#include FT_INTERNAL_SFNT_H
+#include FT_INTERNAL_OBJECTS_H
+
+
+FT_BEGIN_HEADER
+
+
+ FT_LOCAL( FT_Error )
+ woff2_open_font( FT_Stream stream,
+ TT_Face face );
+
+
+FT_END_HEADER
+
+#endif /* SFWOFF2_H_ */
+
+
+/* END */