[sfnt] Separate WOFF sources and headers.

Move WOFF sources and headers to separate files.

* include/freetype/internal/wofftypes.h, src/sfnt/sfwoff.c,
src/sfnt/sfwoff.h: New files.

* include/freetype/internal/fttrace.h: Register `sfwoff.c'.

* include/freetype/internal/internal.h: Define
FT_INTERNAL_WOFF_TYPES_H.

* include/freetype/internal/sfnt.h: Include FT_INTERNAL_WOFF_TYPES_H.

* include/freetype/internal/tttypes.h: Move out WOFF structures.

* src/sfnt/rules.mk: Add `sfwoff.c'.

* src/sfnt/sfnt.c: Include `sfwoff.c'.

* src/sfnt/sfobjs.c: Include `sfwoff.h', move out WOFF sources.

11 files changed, 617 insertions, 473 deletions

diff --git a/ChangeLog b/ChangeLog
index 6513ddd08..55efb87dd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,27 @@
+2019-05-30  Nikhil Ramakrishnan  <ramakrishnan.nikhil@gmail.com>
+
+	[sfnt] Separate WOFF sources and headers.
+
+	Move WOFF sources and headers to separate files.
+
+	* include/freetype/internal/wofftypes.h, src/sfnt/sfwoff.c,
+	src/sfnt/sfwoff.h: New files.
+
+	* include/freetype/internal/fttrace.h: Register `sfwoff.c'.
+
+	* include/freetype/internal/internal.h: Define
+	FT_INTERNAL_WOFF_TYPES_H.
+
+	* include/freetype/internal/sfnt.h: Include FT_INTERNAL_WOFF_TYPES_H.
+
+	* include/freetype/internal/tttypes.h: Move out WOFF structures.
+
+	* src/sfnt/rules.mk: Add `sfwoff.c'.
+
+	* src/sfnt/sfnt.c: Include `sfwoff.c'.
+
+	* src/sfnt/sfobjs.c: Include `sfwoff.h', move out WOFF sources.
+
 2019-05-30  Werner Lemberg  <wl@gnu.org>
 
 	[base] Fix `make multi'.
diff --git a/include/freetype/internal/fttrace.h b/include/freetype/internal/fttrace.h
index 8089babfb..f5f959804 100644
--- a/include/freetype/internal/fttrace.h
+++ b/include/freetype/internal/fttrace.h
@@ -48,6 +48,7 @@ FT_TRACE_DEF( cache )     /* cache sub-system        (ftcache.c, etc.) */
   /* SFNT driver components */
 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( ttbdf )     /* TrueType embedded BDF   (ttbdf.c)    */
 FT_TRACE_DEF( ttcmap )    /* charmap handler         (ttcmap.c)   */
 FT_TRACE_DEF( ttcolr )    /* glyph layer table       (ttcolr.c)   */
diff --git a/include/freetype/internal/internal.h b/include/freetype/internal/internal.h
index 173d8ad90..3c8830f7e 100644
--- a/include/freetype/internal/internal.h
+++ b/include/freetype/internal/internal.h
@@ -40,6 +40,7 @@
 
 #define FT_INTERNAL_TRUETYPE_TYPES_H      <freetype/internal/tttypes.h>
 #define FT_INTERNAL_TYPE1_TYPES_H         <freetype/internal/t1types.h>
+#define FT_INTERNAL_WOFF_TYPES_H          <freetype/internal/wofftypes.h>
 
 #define FT_INTERNAL_POSTSCRIPT_AUX_H      <freetype/internal/psaux.h>
 #define FT_INTERNAL_POSTSCRIPT_HINTS_H    <freetype/internal/pshints.h>
diff --git a/include/freetype/internal/sfnt.h b/include/freetype/internal/sfnt.h
index 225f40df6..b19241c30 100644
--- a/include/freetype/internal/sfnt.h
+++ b/include/freetype/internal/sfnt.h
@@ -23,6 +23,7 @@
 #include <ft2build.h>
 #include FT_INTERNAL_DRIVER_H
 #include FT_INTERNAL_TRUETYPE_TYPES_H
+#include FT_INTERNAL_WOFF_TYPES_H
 
 
 FT_BEGIN_HEADER
diff --git a/include/freetype/internal/tttypes.h b/include/freetype/internal/tttypes.h
index cb03368b3..23db240e7 100644
--- a/include/freetype/internal/tttypes.h
+++ b/include/freetype/internal/tttypes.h
@@ -153,81 +153,6 @@ FT_BEGIN_HEADER
   /**************************************************************************
    *
    * @struct:
-   *   WOFF_HeaderRec
-   *
-   * @description:
-   *   WOFF file format header.
-   *
-   * @fields:
-   *   See
-   *
-   *     https://www.w3.org/TR/WOFF/#WOFFHeader
-   */
-  typedef struct  WOFF_HeaderRec_
-  {
-    FT_ULong   signature;
-    FT_ULong   flavor;
-    FT_ULong   length;
-    FT_UShort  num_tables;
-    FT_UShort  reserved;
-    FT_ULong   totalSfntSize;
-    FT_UShort  majorVersion;
-    FT_UShort  minorVersion;
-    FT_ULong   metaOffset;
-    FT_ULong   metaLength;
-    FT_ULong   metaOrigLength;
-    FT_ULong   privOffset;
-    FT_ULong   privLength;
-
-  } WOFF_HeaderRec, *WOFF_Header;
-
-
-  /**************************************************************************
-   *
-   * @struct:
-   *   WOFF_TableRec
-   *
-   * @description:
-   *   This structure describes a given table of a WOFF font.
-   *
-   * @fields:
-   *   Tag ::
-   *     A four-bytes tag describing the table.
-   *
-   *   Offset ::
-   *     The offset of the table from the start of the WOFF font in its
-   *     resource.
-   *
-   *   CompLength ::
-   *     Compressed table length (in bytes).
-   *
-   *   OrigLength ::
-   *     Uncompressed table length (in bytes).
-   *
-   *   CheckSum ::
-   *     The table checksum.  This value can be ignored.
-   *
-   *   OrigOffset ::
-   *     The uncompressed table file offset.  This value gets computed while
-   *     constructing the (uncompressed) SFNT header.  It is not contained in
-   *     the WOFF file.
-   */
-  typedef struct  WOFF_TableRec_
-  {
-    FT_ULong  Tag;           /* table ID                  */
-    FT_ULong  Offset;        /* table file offset         */
-    FT_ULong  CompLength;    /* compressed table length   */
-    FT_ULong  OrigLength;    /* uncompressed table length */
-    FT_ULong  CheckSum;      /* uncompressed checksum     */
-
-    FT_ULong  OrigOffset;    /* uncompressed table file offset */
-                             /* (not in the WOFF file)         */
-  } WOFF_TableRec, *WOFF_Table;
-
-
-  /**************************************************************************
-   *
-   * @struct:
    *   TT_LongMetricsRec
    *
    * @description:
diff --git a/include/freetype/internal/wofftypes.h b/include/freetype/internal/wofftypes.h
new file mode 100644
index 000000000..ba55bf883
--- /dev/null
+++ b/include/freetype/internal/wofftypes.h
@@ -0,0 +1,112 @@
+/****************************************************************************
+ *
+ * wofftypes.h
+ *
+ *   Basic WOFF/WOFF2 type definitions and interface (specification
+ *   only).
+ *
+ * Copyright (C) 1996-2019 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.
+ *
+ */
+
+
+#ifndef WOFFTYPES_H_
+#define WOFFTYPES_H_
+
+
+#include <ft2build.h>
+#include FT_TRUETYPE_TABLES_H
+#include FT_INTERNAL_OBJECTS_H
+
+
+FT_BEGIN_HEADER
+
+
+  /**************************************************************************
+   *
+   * @struct:
+   *   WOFF_HeaderRec
+   *
+   * @description:
+   *   WOFF file format header.
+   *
+   * @fields:
+   *   See
+   *
+   *     https://www.w3.org/TR/WOFF/#WOFFHeader
+   */
+  typedef struct  WOFF_HeaderRec_
+  {
+    FT_ULong   signature;
+    FT_ULong   flavor;
+    FT_ULong   length;
+    FT_UShort  num_tables;
+    FT_UShort  reserved;
+    FT_ULong   totalSfntSize;
+    FT_UShort  majorVersion;
+    FT_UShort  minorVersion;
+    FT_ULong   metaOffset;
+    FT_ULong   metaLength;
+    FT_ULong   metaOrigLength;
+    FT_ULong   privOffset;
+    FT_ULong   privLength;
+
+  } WOFF_HeaderRec, *WOFF_Header;
+
+
+  /**************************************************************************
+   *
+   * @struct:
+   *   WOFF_TableRec
+   *
+   * @description:
+   *   This structure describes a given table of a WOFF font.
+   *
+   * @fields:
+   *   Tag ::
+   *     A four-bytes tag describing the table.
+   *
+   *   Offset ::
+   *     The offset of the table from the start of the WOFF font in its
+   *     resource.
+   *
+   *   CompLength ::
+   *     Compressed table length (in bytes).
+   *
+   *   OrigLength ::
+   *     Uncompressed table length (in bytes).
+   *
+   *   CheckSum ::
+   *     The table checksum.  This value can be ignored.
+   *
+   *   OrigOffset ::
+   *     The uncompressed table file offset.  This value gets computed while
+   *     constructing the (uncompressed) SFNT header.  It is not contained in
+   *     the WOFF file.
+   */
+  typedef struct  WOFF_TableRec_
+  {
+    FT_ULong  Tag;           /* table ID                  */
+    FT_ULong  Offset;        /* table file offset         */
+    FT_ULong  CompLength;    /* compressed table length   */
+    FT_ULong  OrigLength;    /* uncompressed table length */
+    FT_ULong  CheckSum;      /* uncompressed checksum     */
+
+    FT_ULong  OrigOffset;    /* uncompressed table file offset */
+                             /* (not in the WOFF file)         */
+  } WOFF_TableRec, *WOFF_Table;
+
+
+FT_END_HEADER
+
+#endif /* WOFFTYPES_H_ */
+
+
+/* END */
diff --git a/src/sfnt/rules.mk b/src/sfnt/rules.mk
index ff9e7c611..ee3314eac 100644
--- a/src/sfnt/rules.mk
+++ b/src/sfnt/rules.mk
@@ -31,6 +31,7 @@ SFNT_COMPILE := $(CC) $(ANSIFLAGS)                             \
 SFNT_DRV_SRC := $(SFNT_DIR)/pngshim.c  \
                 $(SFNT_DIR)/sfdriver.c \
                 $(SFNT_DIR)/sfobjs.c   \
+                $(SFNT_DIR)/sfwoff.c   \
                 $(SFNT_DIR)/ttbdf.c    \
                 $(SFNT_DIR)/ttcmap.c   \
                 $(SFNT_DIR)/ttcolr.c   \
diff --git a/src/sfnt/sfnt.c b/src/sfnt/sfnt.c
index 5a503f30c..b4faf34a3 100644
--- a/src/sfnt/sfnt.c
+++ b/src/sfnt/sfnt.c
@@ -22,6 +22,7 @@
 #include "pngshim.c"
 #include "sfdriver.c"
 #include "sfobjs.c"
+#include "sfwoff.c"
 #include "ttbdf.c"
 #include "ttcmap.c"
 #include "ttcolr.c"
diff --git a/src/sfnt/sfobjs.c b/src/sfnt/sfobjs.c
index 0b43d251b..6edf3ae1d 100644
--- a/src/sfnt/sfobjs.c
+++ b/src/sfnt/sfobjs.c
@@ -21,13 +21,13 @@
 #include "ttload.h"
 #include "ttcmap.h"
 #include "ttkern.h"
+#include "sfwoff.h"
 #include FT_INTERNAL_SFNT_H
 #include FT_INTERNAL_DEBUG_H
 #include FT_TRUETYPE_IDS_H
 #include FT_TRUETYPE_TAGS_H
 #include FT_SERVICE_POSTSCRIPT_CMAPS_H
 #include FT_SFNT_NAMES_H
-#include FT_GZIP_H
 
 #ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
 #include FT_SERVICE_MULTIPLE_MASTERS_H
@@ -337,403 +337,6 @@
   }
 
 
-#define WRITE_USHORT( p, v )                \
-          do                                \
-          {                                 \
-            *(p)++ = (FT_Byte)( (v) >> 8 ); \
-            *(p)++ = (FT_Byte)( (v) >> 0 ); \
-                                            \
-          } while ( 0 )
-
-#define WRITE_ULONG( p, v )                  \
-          do                                 \
-          {                                  \
-            *(p)++ = (FT_Byte)( (v) >> 24 ); \
-            *(p)++ = (FT_Byte)( (v) >> 16 ); \
-            *(p)++ = (FT_Byte)( (v) >>  8 ); \
-            *(p)++ = (FT_Byte)( (v) >>  0 ); \
-                                             \
-          } while ( 0 )
-
-
-  static void
-  sfnt_stream_close( FT_Stream  stream )
-  {
-    FT_Memory  memory = stream->memory;
-
-
-    FT_FREE( stream->base );
-
-    stream->size  = 0;
-    stream->base  = NULL;
-    stream->close = NULL;
-  }
-
-
-  FT_CALLBACK_DEF( int )
-  compare_offsets( const void*  a,
-                   const void*  b )
-  {
-    WOFF_Table  table1 = *(WOFF_Table*)a;
-    WOFF_Table  table2 = *(WOFF_Table*)b;
-
-    FT_ULong  offset1 = table1->Offset;
-    FT_ULong  offset2 = table2->Offset;
-
-
-    if ( offset1 > offset2 )
-      return 1;
-    else if ( offset1 < offset2 )
-      return -1;
-    else
-      return 0;
-  }
-
-
-  /* Replace `face->root.stream' with a stream containing the extracted */
-  /* SFNT of a WOFF font.                                               */
-
-  static FT_Error
-  woff_open_font( FT_Stream  stream,
-                  TT_Face    face )
-  {
-    FT_Memory       memory = stream->memory;
-    FT_Error        error  = FT_Err_Ok;
-
-    WOFF_HeaderRec  woff;
-    WOFF_Table      tables  = NULL;
-    WOFF_Table*     indices = NULL;
-
-    FT_ULong        woff_offset;
-
-    FT_Byte*        sfnt        = NULL;
-    FT_Stream       sfnt_stream = NULL;
-
-    FT_Byte*        sfnt_header;
-    FT_ULong        sfnt_offset;
-
-    FT_Int          nn;
-    FT_ULong        old_tag = 0;
-
-    static const FT_Frame_Field  woff_header_fields[] =
-    {
-#undef  FT_STRUCTURE
-#define FT_STRUCTURE  WOFF_HeaderRec
-
-      FT_FRAME_START( 44 ),
-        FT_FRAME_ULONG ( signature ),
-        FT_FRAME_ULONG ( flavor ),
-        FT_FRAME_ULONG ( length ),
-        FT_FRAME_USHORT( num_tables ),
-        FT_FRAME_USHORT( reserved ),
-        FT_FRAME_ULONG ( totalSfntSize ),
-        FT_FRAME_USHORT( majorVersion ),
-        FT_FRAME_USHORT( minorVersion ),
-        FT_FRAME_ULONG ( metaOffset ),
-        FT_FRAME_ULONG ( metaLength ),
-        FT_FRAME_ULONG ( metaOrigLength ),
-        FT_FRAME_ULONG ( privOffset ),
-        FT_FRAME_ULONG ( privLength ),
-      FT_FRAME_END
-    };
-
-
-    FT_ASSERT( stream == face->root.stream );
-    FT_ASSERT( FT_STREAM_POS() == 0 );
-
-    if ( FT_STREAM_READ_FIELDS( woff_header_fields, &woff ) )
-      return error;
-
-    /* Make sure we don't recurse back here or hit TTC code. */
-    if ( woff.flavor == TTAG_wOFF || woff.flavor == TTAG_ttcf )
-      return FT_THROW( Invalid_Table );
-
-    /* Miscellaneous checks. */
-    if ( woff.length != stream->size                              ||
-         woff.num_tables == 0                                     ||
-         44 + woff.num_tables * 20UL >= woff.length               ||
-         12 + woff.num_tables * 16UL >= woff.totalSfntSize        ||
-         ( woff.totalSfntSize & 3 ) != 0                          ||
-         ( woff.metaOffset == 0 && ( woff.metaLength != 0     ||
-                                     woff.metaOrigLength != 0 ) ) ||
-         ( woff.metaLength != 0 && woff.metaOrigLength == 0 )     ||
-         ( woff.privOffset == 0 && woff.privLength != 0 )         )
-    {
-      FT_ERROR(( "woff_font_open: invalid WOFF header\n" ));
-      return FT_THROW( Invalid_Table );
-    }
-
-    /* Don't trust `totalSfntSize' before thorough checks. */
-    if ( FT_ALLOC( sfnt, 12 + woff.num_tables * 16UL ) ||
-         FT_NEW( sfnt_stream )                         )
-      goto Exit;
-
-    sfnt_header = sfnt;
-
-    /* Write sfnt header. */
-    {
-      FT_UInt  searchRange, entrySelector, rangeShift, x;
-
-
-      x             = woff.num_tables;
-      entrySelector = 0;
-      while ( x )
-      {
-        x            >>= 1;
-        entrySelector += 1;
-      }
-      entrySelector--;
-
-      searchRange = ( 1 << entrySelector ) * 16;
-      rangeShift  = woff.num_tables * 16 - searchRange;
-
-      WRITE_ULONG ( sfnt_header, woff.flavor );
-      WRITE_USHORT( sfnt_header, woff.num_tables );
-      WRITE_USHORT( sfnt_header, searchRange );
-      WRITE_USHORT( sfnt_header, entrySelector );
-      WRITE_USHORT( sfnt_header, rangeShift );
-    }
-
-    /* While the entries in the sfnt header must be sorted by the */
-    /* tag value, the tables themselves are not.  We thus have to */
-    /* sort them by offset and check that they don't overlap.     */
-
-    if ( FT_NEW_ARRAY( tables, woff.num_tables )  ||
-         FT_NEW_ARRAY( indices, woff.num_tables ) )
-      goto Exit;
-
-    FT_TRACE2(( "\n"
-                "  tag    offset    compLen  origLen  checksum\n"
-                "  -------------------------------------------\n" ));
-
-    if ( FT_FRAME_ENTER( 20L * woff.num_tables ) )
-      goto Exit;
-
-    for ( nn = 0; nn < woff.num_tables; nn++ )
-    {
-      WOFF_Table  table = tables + nn;
-
-      table->Tag        = FT_GET_TAG4();
-      table->Offset     = FT_GET_ULONG();
-      table->CompLength = FT_GET_ULONG();
-      table->OrigLength = FT_GET_ULONG();
-      table->CheckSum   = FT_GET_ULONG();
-
-      FT_TRACE2(( "  %c%c%c%c  %08lx  %08lx  %08lx  %08lx\n",
-                  (FT_Char)( table->Tag >> 24 ),
-                  (FT_Char)( table->Tag >> 16 ),
-                  (FT_Char)( table->Tag >> 8  ),
-                  (FT_Char)( table->Tag       ),
-                  table->Offset,
-                  table->CompLength,
-                  table->OrigLength,
-                  table->CheckSum ));
-
-      if ( table->Tag <= old_tag )
-      {
-        FT_FRAME_EXIT();
-
-        FT_ERROR(( "woff_font_open: table tags are not sorted\n" ));
-        error = FT_THROW( Invalid_Table );
-        goto Exit;
-      }
-
-      old_tag     = table->Tag;
-      indices[nn] = table;
-    }
-
-    FT_FRAME_EXIT();
-
-    /* Sort by offset. */
-
-    ft_qsort( indices,
-              woff.num_tables,
-              sizeof ( WOFF_Table ),
-              compare_offsets );
-
-    /* Check offsets and lengths. */
-
-    woff_offset = 44 + woff.num_tables * 20L;
-    sfnt_offset = 12 + woff.num_tables * 16L;
-
-    for ( nn = 0; nn < woff.num_tables; nn++ )
-    {
-      WOFF_Table  table = indices[nn];
-
-
-      if ( table->Offset != woff_offset                         ||
-           table->CompLength > woff.length                      ||
-           table->Offset > woff.length - table->CompLength      ||
-           table->OrigLength > woff.totalSfntSize               ||
-           sfnt_offset > woff.totalSfntSize - table->OrigLength ||
-           table->CompLength > table->OrigLength                )
-      {
-        FT_ERROR(( "woff_font_open: invalid table offsets\n" ));
-        error = FT_THROW( Invalid_Table );
-        goto Exit;
-      }
-
-      table->OrigOffset = sfnt_offset;
-
-      /* The offsets must be multiples of 4. */
-      woff_offset += ( table->CompLength + 3 ) & ~3U;
-      sfnt_offset += ( table->OrigLength + 3 ) & ~3U;
-    }
-
-    /*
-     * Final checks!
-     *
-     * We don't decode and check the metadata block.
-     * We don't check table checksums either.
-     * But other than those, I think we implement all
-     * `MUST' checks from the spec.
-     */
-
-    if ( woff.metaOffset )
-    {
-      if ( woff.metaOffset != woff_offset                  ||
-           woff.metaOffset + woff.metaLength > woff.length )
-      {
-        FT_ERROR(( "woff_font_open:"
-                   " invalid `metadata' offset or length\n" ));
-        error = FT_THROW( Invalid_Table );
-        goto Exit;
-      }
-
-      /* We have padding only ... */
-      woff_offset += woff.metaLength;
-    }
-
-    if ( woff.privOffset )
-    {
-      /* ... if it isn't the last block. */
-      woff_offset = ( woff_offset + 3 ) & ~3U;
-
-      if ( woff.privOffset != woff_offset                  ||
-           woff.privOffset + woff.privLength > woff.length )
-      {
-        FT_ERROR(( "woff_font_open: invalid `private' offset or length\n" ));
-        error = FT_THROW( Invalid_Table );
-        goto Exit;
-      }
-
-      /* No padding for the last block. */
-      woff_offset += woff.privLength;
-    }
-
-    if ( sfnt_offset != woff.totalSfntSize ||
-         woff_offset != woff.length        )
-    {
-      FT_ERROR(( "woff_font_open: invalid `sfnt' table structure\n" ));
-      error = FT_THROW( Invalid_Table );
-      goto Exit;
-    }
-
-    /* Now use `totalSfntSize'. */
-    if ( FT_REALLOC( sfnt,
-                     12 + woff.num_tables * 16UL,
-                     woff.totalSfntSize ) )
-      goto Exit;
-
-    sfnt_header = sfnt + 12;
-
-    /* Write the tables. */
-
-    for ( nn = 0; nn < woff.num_tables; nn++ )
-    {
-      WOFF_Table  table = tables + nn;
-
-
-      /* Write SFNT table entry. */
-      WRITE_ULONG( sfnt_header, table->Tag );
-      WRITE_ULONG( sfnt_header, table->CheckSum );
-      WRITE_ULONG( sfnt_header, table->OrigOffset );
-      WRITE_ULONG( sfnt_header, table->OrigLength );
-
-      /* Write table data. */
-      if ( FT_STREAM_SEEK( table->Offset )     ||
-           FT_FRAME_ENTER( table->CompLength ) )
-        goto Exit;
-
-      if ( table->CompLength == table->OrigLength )
-      {
-        /* Uncompressed data; just copy. */
-        ft_memcpy( sfnt + table->OrigOffset,
-                   stream->cursor,
-                   table->OrigLength );
-      }
-      else
-      {
-#ifdef FT_CONFIG_OPTION_USE_ZLIB
-
-        /* Uncompress with zlib. */
-        FT_ULong  output_len = table->OrigLength;
-
-
-        error = FT_Gzip_Uncompress( memory,
-                                    sfnt + table->OrigOffset, &output_len,
-                                    stream->cursor, table->CompLength );
-        if ( error )
-          goto Exit;
-        if ( output_len != table->OrigLength )
-        {
-          FT_ERROR(( "woff_font_open: compressed table length mismatch\n" ));
-          error = FT_THROW( Invalid_Table );
-          goto Exit;
-        }
-
-#else /* !FT_CONFIG_OPTION_USE_ZLIB */
-
-        error = FT_THROW( Unimplemented_Feature );
-        goto Exit;
-
-#endif /* !FT_CONFIG_OPTION_USE_ZLIB */
-      }
-
-      FT_FRAME_EXIT();
-
-      /* We don't check whether the padding bytes in the WOFF file are     */
-      /* actually '\0'.  For the output, however, we do set them properly. */
-      sfnt_offset = table->OrigOffset + table->OrigLength;
-      while ( sfnt_offset & 3 )
-      {
-        sfnt[sfnt_offset] = '\0';
-        sfnt_offset++;
-      }
-    }
-
-    /* Ok!  Finally ready.  Swap out stream and return. */
-    FT_Stream_OpenMemory( sfnt_stream, sfnt, woff.totalSfntSize );
-    sfnt_stream->memory = stream->memory;
-    sfnt_stream->close  = sfnt_stream_close;
-
-    FT_Stream_Free(
-      face->root.stream,
-      ( face->root.face_flags & FT_FACE_FLAG_EXTERNAL_STREAM ) != 0 );
-
-    face->root.stream = sfnt_stream;
-
-    face->root.face_flags &= ~FT_FACE_FLAG_EXTERNAL_STREAM;
-
-  Exit:
-    FT_FREE( tables );
-    FT_FREE( indices );
-
-    if ( error )
-    {
-      FT_FREE( sfnt );
-      FT_Stream_Close( sfnt_stream );
-      FT_FREE( sfnt_stream );
-    }
-
-    return error;
-  }
-
-
-#undef WRITE_USHORT
-#undef WRITE_ULONG
-
-
   /* Fill in face->ttc_header.  If the font is not a TTC, it is */
   /* synthesized into a TTC with one offset table.              */
   static FT_Error
diff --git a/src/sfnt/sfwoff.c b/src/sfnt/sfwoff.c
new file mode 100644
index 000000000..ca4821a20
--- /dev/null
+++ b/src/sfnt/sfwoff.c
@@ -0,0 +1,434 @@
+/****************************************************************************
+ *
+ * sfwoff.c
+ *
+ *   WOFF format management (base).
+ *
+ * Copyright (C) 1996-2019 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.
+ *
+ */
+
+
+#include <ft2build.h>
+#include "sfwoff.h"
+#include FT_TRUETYPE_TAGS_H
+#include FT_INTERNAL_DEBUG_H
+#include FT_INTERNAL_STREAM_H
+#include FT_GZIP_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  sfwoff
+
+
+#define WRITE_USHORT( p, v )                \
+          do                                \
+          {                                 \
+            *(p)++ = (FT_Byte)( (v) >> 8 ); \
+            *(p)++ = (FT_Byte)( (v) >> 0 ); \
+                                            \
+          } while ( 0 )
+
+#define WRITE_ULONG( p, v )                  \
+          do                                 \
+          {                                  \
+            *(p)++ = (FT_Byte)( (v) >> 24 ); \
+            *(p)++ = (FT_Byte)( (v) >> 16 ); \
+            *(p)++ = (FT_Byte)( (v) >>  8 ); \
+            *(p)++ = (FT_Byte)( (v) >>  0 ); \
+                                             \
+          } while ( 0 )
+
+
+  static void
+  sfnt_stream_close( FT_Stream  stream )
+  {
+    FT_Memory  memory = stream->memory;
+
+
+    FT_FREE( stream->base );
+
+    stream->size  = 0;
+    stream->base  = NULL;
+    stream->close = NULL;
+  }
+
+
+  FT_CALLBACK_DEF( int )
+  compare_offsets( const void*  a,
+                   const void*  b )
+  {
+    WOFF_Table  table1 = *(WOFF_Table*)a;
+    WOFF_Table  table2 = *(WOFF_Table*)b;
+
+    FT_ULong  offset1 = table1->Offset;
+    FT_ULong  offset2 = table2->Offset;
+
+
+    if ( offset1 > offset2 )
+      return 1;
+    else if ( offset1 < offset2 )
+      return -1;
+    else
+      return 0;
+  }
+
+
+  /* Replace `face->root.stream' with a stream containing the extracted */
+  /* SFNT of a WOFF font.                                               */
+
+  FT_LOCAL_DEF( FT_Error )
+  woff_open_font( FT_Stream  stream,
+                  TT_Face    face )
+  {
+    FT_Memory       memory = stream->memory;
+    FT_Error        error  = FT_Err_Ok;
+
+    WOFF_HeaderRec  woff;
+    WOFF_Table      tables  = NULL;
+    WOFF_Table*     indices = NULL;
+
+    FT_ULong        woff_offset;
+
+    FT_Byte*        sfnt        = NULL;
+    FT_Stream       sfnt_stream = NULL;
+
+    FT_Byte*        sfnt_header;
+    FT_ULong        sfnt_offset;
+
+    FT_Int          nn;
+    FT_ULong        old_tag = 0;
+
+    static const FT_Frame_Field  woff_header_fields[] =
+    {
+#undef  FT_STRUCTURE
+#define FT_STRUCTURE  WOFF_HeaderRec
+
+      FT_FRAME_START( 44 ),
+        FT_FRAME_ULONG ( signature ),
+        FT_FRAME_ULONG ( flavor ),
+        FT_FRAME_ULONG ( length ),
+        FT_FRAME_USHORT( num_tables ),
+        FT_FRAME_USHORT( reserved ),
+        FT_FRAME_ULONG ( totalSfntSize ),
+        FT_FRAME_USHORT( majorVersion ),
+        FT_FRAME_USHORT( minorVersion ),
+        FT_FRAME_ULONG ( metaOffset ),
+        FT_FRAME_ULONG ( metaLength ),
+        FT_FRAME_ULONG ( metaOrigLength ),
+        FT_FRAME_ULONG ( privOffset ),
+        FT_FRAME_ULONG ( privLength ),
+      FT_FRAME_END
+    };
+
+
+    FT_ASSERT( stream == face->root.stream );
+    FT_ASSERT( FT_STREAM_POS() == 0 );
+
+    if ( FT_STREAM_READ_FIELDS( woff_header_fields, &woff ) )
+      return error;
+
+    /* Make sure we don't recurse back here or hit TTC code. */
+    if ( woff.flavor == TTAG_wOFF || woff.flavor == TTAG_ttcf )
+      return FT_THROW( Invalid_Table );
+
+    /* Miscellaneous checks. */
+    if ( woff.length != stream->size                              ||
+         woff.num_tables == 0                                     ||
+         44 + woff.num_tables * 20UL >= woff.length               ||
+         12 + woff.num_tables * 16UL >= woff.totalSfntSize        ||
+         ( woff.totalSfntSize & 3 ) != 0                          ||
+         ( woff.metaOffset == 0 && ( woff.metaLength != 0     ||
+                                     woff.metaOrigLength != 0 ) ) ||
+         ( woff.metaLength != 0 && woff.metaOrigLength == 0 )     ||
+         ( woff.privOffset == 0 && woff.privLength != 0 )         )
+    {
+      FT_ERROR(( "woff_font_open: invalid WOFF header\n" ));
+      return FT_THROW( Invalid_Table );
+    }
+
+    /* Don't trust `totalSfntSize' before thorough checks. */
+    if ( FT_ALLOC( sfnt, 12 + woff.num_tables * 16UL ) ||
+         FT_NEW( sfnt_stream )                         )
+      goto Exit;
+
+    sfnt_header = sfnt;
+
+    /* Write sfnt header. */
+    {
+      FT_UInt  searchRange, entrySelector, rangeShift, x;
+
+
+      x             = woff.num_tables;
+      entrySelector = 0;
+      while ( x )
+      {
+        x            >>= 1;
+        entrySelector += 1;
+      }
+      entrySelector--;
+
+      searchRange = ( 1 << entrySelector ) * 16;
+      rangeShift  = woff.num_tables * 16 - searchRange;
+
+      WRITE_ULONG ( sfnt_header, woff.flavor );
+      WRITE_USHORT( sfnt_header, woff.num_tables );
+      WRITE_USHORT( sfnt_header, searchRange );
+      WRITE_USHORT( sfnt_header, entrySelector );
+      WRITE_USHORT( sfnt_header, rangeShift );
+    }
+
+    /* While the entries in the sfnt header must be sorted by the */
+    /* tag value, the tables themselves are not.  We thus have to */
+    /* sort them by offset and check that they don't overlap.     */
+
+    if ( FT_NEW_ARRAY( tables, woff.num_tables )  ||
+         FT_NEW_ARRAY( indices, woff.num_tables ) )
+      goto Exit;
+
+    FT_TRACE2(( "\n"
+                "  tag    offset    compLen  origLen  checksum\n"
+                "  -------------------------------------------\n" ));
+
+    if ( FT_FRAME_ENTER( 20L * woff.num_tables ) )
+      goto Exit;
+
+    for ( nn = 0; nn < woff.num_tables; nn++ )
+    {
+      WOFF_Table  table = tables + nn;
+
+      table->Tag        = FT_GET_TAG4();
+      table->Offset     = FT_GET_ULONG();
+      table->CompLength = FT_GET_ULONG();
+      table->OrigLength = FT_GET_ULONG();
+      table->CheckSum   = FT_GET_ULONG();
+
+      FT_TRACE2(( "  %c%c%c%c  %08lx  %08lx  %08lx  %08lx\n",
+                  (FT_Char)( table->Tag >> 24 ),
+                  (FT_Char)( table->Tag >> 16 ),
+                  (FT_Char)( table->Tag >> 8  ),
+                  (FT_Char)( table->Tag       ),
+                  table->Offset,
+                  table->CompLength,
+                  table->OrigLength,
+                  table->CheckSum ));
+
+      if ( table->Tag <= old_tag )
+      {
+        FT_FRAME_EXIT();
+
+        FT_ERROR(( "woff_font_open: table tags are not sorted\n" ));
+        error = FT_THROW( Invalid_Table );
+        goto Exit;
+      }
+
+      old_tag     = table->Tag;
+      indices[nn] = table;
+    }
+
+    FT_FRAME_EXIT();
+
+    /* Sort by offset. */
+
+    ft_qsort( indices,
+              woff.num_tables,
+              sizeof ( WOFF_Table ),
+              compare_offsets );
+
+    /* Check offsets and lengths. */
+
+    woff_offset = 44 + woff.num_tables * 20L;
+    sfnt_offset = 12 + woff.num_tables * 16L;
+
+    for ( nn = 0; nn < woff.num_tables; nn++ )
+    {
+      WOFF_Table  table = indices[nn];
+
+
+      if ( table->Offset != woff_offset                         ||
+           table->CompLength > woff.length                      ||
+           table->Offset > woff.length - table->CompLength      ||
+           table->OrigLength > woff.totalSfntSize               ||
+           sfnt_offset > woff.totalSfntSize - table->OrigLength ||
+           table->CompLength > table->OrigLength                )
+      {
+        FT_ERROR(( "woff_font_open: invalid table offsets\n" ));
+        error = FT_THROW( Invalid_Table );
+        goto Exit;
+      }
+
+      table->OrigOffset = sfnt_offset;
+
+      /* The offsets must be multiples of 4. */
+      woff_offset += ( table->CompLength + 3 ) & ~3U;
+      sfnt_offset += ( table->OrigLength + 3 ) & ~3U;
+    }
+
+    /*
+     * Final checks!
+     *
+     * We don't decode and check the metadata block.
+     * We don't check table checksums either.
+     * But other than those, I think we implement all
+     * `MUST' checks from the spec.
+     */
+
+    if ( woff.metaOffset )
+    {
+      if ( woff.metaOffset != woff_offset                  ||
+           woff.metaOffset + woff.metaLength > woff.length )
+      {
+        FT_ERROR(( "woff_font_open:"
+                   " invalid `metadata' offset or length\n" ));
+        error = FT_THROW( Invalid_Table );
+        goto Exit;
+      }
+
+      /* We have padding only ... */
+      woff_offset += woff.metaLength;
+    }
+
+    if ( woff.privOffset )
+    {
+      /* ... if it isn't the last block. */
+      woff_offset = ( woff_offset + 3 ) & ~3U;
+
+      if ( woff.privOffset != woff_offset                  ||
+           woff.privOffset + woff.privLength > woff.length )
+      {
+        FT_ERROR(( "woff_font_open: invalid `private' offset or length\n" ));
+        error = FT_THROW( Invalid_Table );
+        goto Exit;
+      }
+
+      /* No padding for the last block. */
+      woff_offset += woff.privLength;
+    }
+
+    if ( sfnt_offset != woff.totalSfntSize ||
+         woff_offset != woff.length        )
+    {
+      FT_ERROR(( "woff_font_open: invalid `sfnt' table structure\n" ));
+      error = FT_THROW( Invalid_Table );
+      goto Exit;
+    }
+
+    /* Now use `totalSfntSize'. */
+    if ( FT_REALLOC( sfnt,
+                     12 + woff.num_tables * 16UL,
+                     woff.totalSfntSize ) )
+      goto Exit;
+
+    sfnt_header = sfnt + 12;
+
+    /* Write the tables. */
+
+    for ( nn = 0; nn < woff.num_tables; nn++ )
+    {
+      WOFF_Table  table = tables + nn;
+
+
+      /* Write SFNT table entry. */
+      WRITE_ULONG( sfnt_header, table->Tag );
+      WRITE_ULONG( sfnt_header, table->CheckSum );
+      WRITE_ULONG( sfnt_header, table->OrigOffset );
+      WRITE_ULONG( sfnt_header, table->OrigLength );
+
+      /* Write table data. */
+      if ( FT_STREAM_SEEK( table->Offset )     ||
+           FT_FRAME_ENTER( table->CompLength ) )
+        goto Exit;
+
+      if ( table->CompLength == table->OrigLength )
+      {
+        /* Uncompressed data; just copy. */
+        ft_memcpy( sfnt + table->OrigOffset,
+                   stream->cursor,
+                   table->OrigLength );
+      }
+      else
+      {
+#ifdef FT_CONFIG_OPTION_USE_ZLIB
+
+        /* Uncompress with zlib. */
+        FT_ULong  output_len = table->OrigLength;
+
+
+        error = FT_Gzip_Uncompress( memory,
+                                    sfnt + table->OrigOffset, &output_len,
+                                    stream->cursor, table->CompLength );
+        if ( error )
+          goto Exit;
+        if ( output_len != table->OrigLength )
+        {
+          FT_ERROR(( "woff_font_open: compressed table length mismatch\n" ));
+          error = FT_THROW( Invalid_Table );
+          goto Exit;
+        }
+
+#else /* !FT_CONFIG_OPTION_USE_ZLIB */
+
+        error = FT_THROW( Unimplemented_Feature );
+        goto Exit;
+
+#endif /* !FT_CONFIG_OPTION_USE_ZLIB */
+      }
+
+      FT_FRAME_EXIT();
+
+      /* We don't check whether the padding bytes in the WOFF file are     */
+      /* actually '\0'.  For the output, however, we do set them properly. */
+      sfnt_offset = table->OrigOffset + table->OrigLength;
+      while ( sfnt_offset & 3 )
+      {
+        sfnt[sfnt_offset] = '\0';
+        sfnt_offset++;
+      }
+    }
+
+    /* Ok!  Finally ready.  Swap out stream and return. */
+    FT_Stream_OpenMemory( sfnt_stream, sfnt, woff.totalSfntSize );
+    sfnt_stream->memory = stream->memory;
+    sfnt_stream->close  = sfnt_stream_close;
+
+    FT_Stream_Free(
+      face->root.stream,
+      ( face->root.face_flags & FT_FACE_FLAG_EXTERNAL_STREAM ) != 0 );
+
+    face->root.stream = sfnt_stream;
+
+    face->root.face_flags &= ~FT_FACE_FLAG_EXTERNAL_STREAM;
+
+  Exit:
+    FT_FREE( tables );
+    FT_FREE( indices );
+
+    if ( error )
+    {
+      FT_FREE( sfnt );
+      FT_Stream_Close( sfnt_stream );
+      FT_FREE( sfnt_stream );
+    }
+
+    return error;
+  }
+
+
+#undef WRITE_USHORT
+#undef WRITE_ULONG
+
+
+/* END */
diff --git a/src/sfnt/sfwoff.h b/src/sfnt/sfwoff.h
new file mode 100644
index 000000000..15495c32a
--- /dev/null
+++ b/src/sfnt/sfwoff.h
@@ -0,0 +1,41 @@
+/****************************************************************************
+ *
+ * sfwoff.h
+ *
+ *   WOFFF format management (specification).
+ *
+ * Copyright (C) 1996-2019 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.
+ *
+ */
+
+
+#ifndef SFWOFF_H_
+#define SFWOFF_H_
+
+
+#include <ft2build.h>
+#include FT_INTERNAL_SFNT_H
+#include FT_INTERNAL_OBJECTS_H
+
+
+FT_BEGIN_HEADER
+
+
+  FT_LOCAL( FT_Error )
+  woff_open_font( FT_Stream  stream,
+                  TT_Face    face );
+
+
+FT_END_HEADER
+
+#endif /* SFWOFF_H_ */
+
+
+/* END */