1 /****************************************************************************
2  *
3  * ftgzip.c
4  *
5  *   FreeType support for .gz compressed files.
6  *
7  * This optional component relies on zlib.  It should mainly be used to
8  * parse compressed PCF fonts, as found with many X11 server
9  * distributions.
10  *
11  * Copyright (C) 2002-2020 by
12  * David Turner, Robert Wilhelm, and Werner Lemberg.
13  *
14  * This file is part of the FreeType project, and may only be used,
15  * modified, and distributed under the terms of the FreeType project
16  * license, LICENSE.TXT.  By continuing to use, modify, or distribute
17  * this file you indicate that you have read the license and
18  * understand and accept it fully.
19  *
20  */
21 
22 
23 #include <freetype/internal/ftmemory.h>
24 #include <freetype/internal/ftstream.h>
25 #include <freetype/internal/ftdebug.h>
26 #include <freetype/ftgzip.h>
27 #include FT_CONFIG_STANDARD_LIBRARY_H
28 
29 
30 #include <freetype/ftmoderr.h>
31 
32 #undef FTERRORS_H_
33 
34 #undef  FT_ERR_PREFIX
35 #define FT_ERR_PREFIX  Gzip_Err_
36 #define FT_ERR_BASE    FT_Mod_Err_Gzip
37 
38 #include <freetype/fterrors.h>
39 
40 
41 #ifdef FT_CONFIG_OPTION_USE_ZLIB
42 
43 #ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB
44 
45 #include <zlib.h>
46 
47 #else /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
48 
49   /* In this case, we include our own modified sources of the ZLib  */
50   /* within the `gzip' component.  The modifications were necessary */
51   /* to #include all files without conflicts, as well as preventing */
52   /* the definition of `extern' functions that may cause linking    */
53   /* conflicts when a program is linked with both FreeType and the  */
54   /* original ZLib.                                                 */
55 
56 #ifndef USE_ZLIB_ZCALLOC
57 #define MY_ZCALLOC /* prevent all zcalloc() & zfree() in zutil.c */
58 #endif
59 
60   /* Note that our `zlib.h' includes `ftzconf.h' instead of `zconf.h'; */
61   /* the main reason is that even a global `zlib.h' includes `zconf.h' */
62   /* with                                                              */
63   /*                                                                   */
64   /*   #include "zconf.h"                                              */
65   /*                                                                   */
66   /* instead of the expected                                           */
67   /*                                                                   */
68   /*   #include <zconf.h>                                              */
69   /*                                                                   */
70   /* so that configuration with `FT_CONFIG_OPTION_SYSTEM_ZLIB' might   */
71   /* include the wrong `zconf.h' file, leading to errors.              */
72 #include "zlib.h"
73 
74 #undef  SLOW
75 #define SLOW  1  /* we can't use asm-optimized sources here! */
76 
77 #if defined( _MSC_VER )      /* Visual C++ (and Intel C++)   */
78   /* We disable the warning `conversion from XXX to YYY,     */
79   /* possible loss of data' in order to compile cleanly with */
80   /* the maximum level of warnings: zlib is non-FreeType     */
81   /* code.                                                   */
82 #pragma warning( push )
83 #pragma warning( disable : 4244 )
84 #endif /* _MSC_VER */
85 
86   /* Urgh.  `inflate_mask' must not be declared twice -- C++ doesn't like
87      this.  We temporarily disable it and load all necessary header files. */
88 #define NO_INFLATE_MASK
89 #include "zutil.h"
90 #include "inftrees.h"
91 #include "infblock.h"
92 #include "infcodes.h"
93 #include "infutil.h"
94 #undef  NO_INFLATE_MASK
95 
96   /* infutil.c must be included before infcodes.c */
97 #include "zutil.c"
98 #include "inftrees.c"
99 #include "infutil.c"
100 #include "infcodes.c"
101 #include "infblock.c"
102 #include "inflate.c"
103 #include "adler32.c"
104 
105 #if defined( _MSC_VER )
106 #pragma warning( pop )
107 #endif
108 
109 #endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
110 
111 
112 /***************************************************************************/
113 /***************************************************************************/
114 /*****                                                                 *****/
115 /*****            Z L I B   M E M O R Y   M A N A G E M E N T          *****/
116 /*****                                                                 *****/
117 /***************************************************************************/
118 /***************************************************************************/
119 
120   /* it is better to use FreeType memory routines instead of raw
121      'malloc/free' */
122 
123   static voidpf
ft_gzip_alloc(FT_Memory memory,uInt items,uInt size)124   ft_gzip_alloc( FT_Memory  memory,
125                  uInt       items,
126                  uInt       size )
127   {
128     FT_ULong    sz = (FT_ULong)size * items;
129     FT_Error    error;
130     FT_Pointer  p  = NULL;
131 
132 
133     (void)FT_ALLOC( p, sz );
134     return p;
135   }
136 
137 
138   static void
ft_gzip_free(FT_Memory memory,voidpf address)139   ft_gzip_free( FT_Memory  memory,
140                 voidpf     address )
141   {
142     FT_MEM_FREE( address );
143   }
144 
145 
146 #if !defined( FT_CONFIG_OPTION_SYSTEM_ZLIB ) && !defined( USE_ZLIB_ZCALLOC )
147 
148   local voidpf
zcalloc(voidpf opaque,unsigned items,unsigned size)149   zcalloc ( voidpf    opaque,
150             unsigned  items,
151             unsigned  size )
152   {
153     return ft_gzip_alloc( (FT_Memory)opaque, items, size );
154   }
155 
156   local void
zcfree(voidpf opaque,voidpf ptr)157   zcfree( voidpf  opaque,
158           voidpf  ptr )
159   {
160     ft_gzip_free( (FT_Memory)opaque, ptr );
161   }
162 
163 #endif /* !SYSTEM_ZLIB && !USE_ZLIB_ZCALLOC */
164 
165 
166 /***************************************************************************/
167 /***************************************************************************/
168 /*****                                                                 *****/
169 /*****               Z L I B   F I L E   D E S C R I P T O R           *****/
170 /*****                                                                 *****/
171 /***************************************************************************/
172 /***************************************************************************/
173 
174 #define FT_GZIP_BUFFER_SIZE  4096
175 
176   typedef struct  FT_GZipFileRec_
177   {
178     FT_Stream  source;         /* parent/source stream        */
179     FT_Stream  stream;         /* embedding stream            */
180     FT_Memory  memory;         /* memory allocator            */
181     z_stream   zstream;        /* zlib input stream           */
182 
183     FT_ULong   start;          /* starting position, after .gz header */
184     FT_Byte    input[FT_GZIP_BUFFER_SIZE];   /* input read buffer  */
185 
186     FT_Byte    buffer[FT_GZIP_BUFFER_SIZE];  /* output buffer      */
187     FT_ULong   pos;                          /* position in output */
188     FT_Byte*   cursor;
189     FT_Byte*   limit;
190 
191   } FT_GZipFileRec, *FT_GZipFile;
192 
193 
194   /* gzip flag byte */
195 #define FT_GZIP_ASCII_FLAG   0x01 /* bit 0 set: file probably ascii text */
196 #define FT_GZIP_HEAD_CRC     0x02 /* bit 1 set: header CRC present */
197 #define FT_GZIP_EXTRA_FIELD  0x04 /* bit 2 set: extra field present */
198 #define FT_GZIP_ORIG_NAME    0x08 /* bit 3 set: original file name present */
199 #define FT_GZIP_COMMENT      0x10 /* bit 4 set: file comment present */
200 #define FT_GZIP_RESERVED     0xE0 /* bits 5..7: reserved */
201 
202 
203   /* check and skip .gz header - we don't support `transparent' compression */
204   static FT_Error
ft_gzip_check_header(FT_Stream stream)205   ft_gzip_check_header( FT_Stream  stream )
206   {
207     FT_Error  error;
208     FT_Byte   head[4];
209 
210 
211     if ( FT_STREAM_SEEK( 0 )       ||
212          FT_STREAM_READ( head, 4 ) )
213       goto Exit;
214 
215     /* head[0] && head[1] are the magic numbers;    */
216     /* head[2] is the method, and head[3] the flags */
217     if ( head[0] != 0x1F              ||
218          head[1] != 0x8B              ||
219          head[2] != Z_DEFLATED        ||
220         (head[3] & FT_GZIP_RESERVED)  )
221     {
222       error = FT_THROW( Invalid_File_Format );
223       goto Exit;
224     }
225 
226     /* skip time, xflags and os code */
227     (void)FT_STREAM_SKIP( 6 );
228 
229     /* skip the extra field */
230     if ( head[3] & FT_GZIP_EXTRA_FIELD )
231     {
232       FT_UInt  len;
233 
234 
235       if ( FT_READ_USHORT_LE( len ) ||
236            FT_STREAM_SKIP( len )    )
237         goto Exit;
238     }
239 
240     /* skip original file name */
241     if ( head[3] & FT_GZIP_ORIG_NAME )
242       for (;;)
243       {
244         FT_UInt  c;
245 
246 
247         if ( FT_READ_BYTE( c ) )
248           goto Exit;
249 
250         if ( c == 0 )
251           break;
252       }
253 
254     /* skip .gz comment */
255     if ( head[3] & FT_GZIP_COMMENT )
256       for (;;)
257       {
258         FT_UInt  c;
259 
260 
261         if ( FT_READ_BYTE( c ) )
262           goto Exit;
263 
264         if ( c == 0 )
265           break;
266       }
267 
268     /* skip CRC */
269     if ( head[3] & FT_GZIP_HEAD_CRC )
270       if ( FT_STREAM_SKIP( 2 ) )
271         goto Exit;
272 
273   Exit:
274     return error;
275   }
276 
277 
278   static FT_Error
ft_gzip_file_init(FT_GZipFile zip,FT_Stream stream,FT_Stream source)279   ft_gzip_file_init( FT_GZipFile  zip,
280                      FT_Stream    stream,
281                      FT_Stream    source )
282   {
283     z_stream*  zstream = &zip->zstream;
284     FT_Error   error   = FT_Err_Ok;
285 
286 
287     zip->stream = stream;
288     zip->source = source;
289     zip->memory = stream->memory;
290 
291     zip->limit  = zip->buffer + FT_GZIP_BUFFER_SIZE;
292     zip->cursor = zip->limit;
293     zip->pos    = 0;
294 
295     /* check and skip .gz header */
296     {
297       stream = source;
298 
299       error = ft_gzip_check_header( stream );
300       if ( error )
301         goto Exit;
302 
303       zip->start = FT_STREAM_POS();
304     }
305 
306     /* initialize zlib -- there is no zlib header in the compressed stream */
307     zstream->zalloc = (alloc_func)ft_gzip_alloc;
308     zstream->zfree  = (free_func) ft_gzip_free;
309     zstream->opaque = stream->memory;
310 
311     zstream->avail_in = 0;
312     zstream->next_in  = zip->buffer;
313 
314     if ( inflateInit2( zstream, -MAX_WBITS ) != Z_OK ||
315          !zstream->next_in                           )
316       error = FT_THROW( Invalid_File_Format );
317 
318   Exit:
319     return error;
320   }
321 
322 
323   static void
ft_gzip_file_done(FT_GZipFile zip)324   ft_gzip_file_done( FT_GZipFile  zip )
325   {
326     z_stream*  zstream = &zip->zstream;
327 
328 
329     inflateEnd( zstream );
330 
331     /* clear the rest */
332     zstream->zalloc    = NULL;
333     zstream->zfree     = NULL;
334     zstream->opaque    = NULL;
335     zstream->next_in   = NULL;
336     zstream->next_out  = NULL;
337     zstream->avail_in  = 0;
338     zstream->avail_out = 0;
339 
340     zip->memory = NULL;
341     zip->source = NULL;
342     zip->stream = NULL;
343   }
344 
345 
346   static FT_Error
ft_gzip_file_reset(FT_GZipFile zip)347   ft_gzip_file_reset( FT_GZipFile  zip )
348   {
349     FT_Stream  stream = zip->source;
350     FT_Error   error;
351 
352 
353     if ( !FT_STREAM_SEEK( zip->start ) )
354     {
355       z_stream*  zstream = &zip->zstream;
356 
357 
358       inflateReset( zstream );
359 
360       zstream->avail_in  = 0;
361       zstream->next_in   = zip->input;
362       zstream->avail_out = 0;
363       zstream->next_out  = zip->buffer;
364 
365       zip->limit  = zip->buffer + FT_GZIP_BUFFER_SIZE;
366       zip->cursor = zip->limit;
367       zip->pos    = 0;
368     }
369 
370     return error;
371   }
372 
373 
374   static FT_Error
ft_gzip_file_fill_input(FT_GZipFile zip)375   ft_gzip_file_fill_input( FT_GZipFile  zip )
376   {
377     z_stream*  zstream = &zip->zstream;
378     FT_Stream  stream  = zip->source;
379     FT_ULong   size;
380 
381 
382     if ( stream->read )
383     {
384       size = stream->read( stream, stream->pos, zip->input,
385                            FT_GZIP_BUFFER_SIZE );
386       if ( size == 0 )
387       {
388         zip->limit = zip->cursor;
389         return FT_THROW( Invalid_Stream_Operation );
390       }
391     }
392     else
393     {
394       size = stream->size - stream->pos;
395       if ( size > FT_GZIP_BUFFER_SIZE )
396         size = FT_GZIP_BUFFER_SIZE;
397 
398       if ( size == 0 )
399       {
400         zip->limit = zip->cursor;
401         return FT_THROW( Invalid_Stream_Operation );
402       }
403 
404       FT_MEM_COPY( zip->input, stream->base + stream->pos, size );
405     }
406     stream->pos += size;
407 
408     zstream->next_in  = zip->input;
409     zstream->avail_in = size;
410 
411     return FT_Err_Ok;
412   }
413 
414 
415   static FT_Error
ft_gzip_file_fill_output(FT_GZipFile zip)416   ft_gzip_file_fill_output( FT_GZipFile  zip )
417   {
418     z_stream*  zstream = &zip->zstream;
419     FT_Error   error   = FT_Err_Ok;
420 
421 
422     zip->cursor        = zip->buffer;
423     zstream->next_out  = zip->cursor;
424     zstream->avail_out = FT_GZIP_BUFFER_SIZE;
425 
426     while ( zstream->avail_out > 0 )
427     {
428       int  err;
429 
430 
431       if ( zstream->avail_in == 0 )
432       {
433         error = ft_gzip_file_fill_input( zip );
434         if ( error )
435           break;
436       }
437 
438       err = inflate( zstream, Z_NO_FLUSH );
439 
440       if ( err == Z_STREAM_END )
441       {
442         zip->limit = zstream->next_out;
443         if ( zip->limit == zip->cursor )
444           error = FT_THROW( Invalid_Stream_Operation );
445         break;
446       }
447       else if ( err != Z_OK )
448       {
449         zip->limit = zip->cursor;
450         error      = FT_THROW( Invalid_Stream_Operation );
451         break;
452       }
453     }
454 
455     return error;
456   }
457 
458 
459   /* fill output buffer; `count' must be <= FT_GZIP_BUFFER_SIZE */
460   static FT_Error
ft_gzip_file_skip_output(FT_GZipFile zip,FT_ULong count)461   ft_gzip_file_skip_output( FT_GZipFile  zip,
462                             FT_ULong     count )
463   {
464     FT_Error  error = FT_Err_Ok;
465     FT_ULong  delta;
466 
467 
468     for (;;)
469     {
470       delta = (FT_ULong)( zip->limit - zip->cursor );
471       if ( delta >= count )
472         delta = count;
473 
474       zip->cursor += delta;
475       zip->pos    += delta;
476 
477       count -= delta;
478       if ( count == 0 )
479         break;
480 
481       error = ft_gzip_file_fill_output( zip );
482       if ( error )
483         break;
484     }
485 
486     return error;
487   }
488 
489 
490   static FT_ULong
ft_gzip_file_io(FT_GZipFile zip,FT_ULong pos,FT_Byte * buffer,FT_ULong count)491   ft_gzip_file_io( FT_GZipFile  zip,
492                    FT_ULong     pos,
493                    FT_Byte*     buffer,
494                    FT_ULong     count )
495   {
496     FT_ULong  result = 0;
497     FT_Error  error;
498 
499 
500     /* Reset inflate stream if we're seeking backwards.        */
501     /* Yes, that is not too efficient, but it saves memory :-) */
502     if ( pos < zip->pos )
503     {
504       error = ft_gzip_file_reset( zip );
505       if ( error )
506         goto Exit;
507     }
508 
509     /* skip unwanted bytes */
510     if ( pos > zip->pos )
511     {
512       error = ft_gzip_file_skip_output( zip, (FT_ULong)( pos - zip->pos ) );
513       if ( error )
514         goto Exit;
515     }
516 
517     if ( count == 0 )
518       goto Exit;
519 
520     /* now read the data */
521     for (;;)
522     {
523       FT_ULong  delta;
524 
525 
526       delta = (FT_ULong)( zip->limit - zip->cursor );
527       if ( delta >= count )
528         delta = count;
529 
530       FT_MEM_COPY( buffer, zip->cursor, delta );
531       buffer      += delta;
532       result      += delta;
533       zip->cursor += delta;
534       zip->pos    += delta;
535 
536       count -= delta;
537       if ( count == 0 )
538         break;
539 
540       error = ft_gzip_file_fill_output( zip );
541       if ( error )
542         break;
543     }
544 
545   Exit:
546     return result;
547   }
548 
549 
550 /***************************************************************************/
551 /***************************************************************************/
552 /*****                                                                 *****/
553 /*****               G Z   E M B E D D I N G   S T R E A M             *****/
554 /*****                                                                 *****/
555 /***************************************************************************/
556 /***************************************************************************/
557 
558   static void
ft_gzip_stream_close(FT_Stream stream)559   ft_gzip_stream_close( FT_Stream  stream )
560   {
561     FT_GZipFile  zip    = (FT_GZipFile)stream->descriptor.pointer;
562     FT_Memory    memory = stream->memory;
563 
564 
565     if ( zip )
566     {
567       /* finalize gzip file descriptor */
568       ft_gzip_file_done( zip );
569 
570       FT_FREE( zip );
571 
572       stream->descriptor.pointer = NULL;
573     }
574 
575     if ( !stream->read )
576       FT_FREE( stream->base );
577   }
578 
579 
580   static unsigned long
ft_gzip_stream_io(FT_Stream stream,unsigned long offset,unsigned char * buffer,unsigned long count)581   ft_gzip_stream_io( FT_Stream       stream,
582                      unsigned long   offset,
583                      unsigned char*  buffer,
584                      unsigned long   count )
585   {
586     FT_GZipFile  zip = (FT_GZipFile)stream->descriptor.pointer;
587 
588 
589     return ft_gzip_file_io( zip, offset, buffer, count );
590   }
591 
592 
593   static FT_ULong
ft_gzip_get_uncompressed_size(FT_Stream stream)594   ft_gzip_get_uncompressed_size( FT_Stream  stream )
595   {
596     FT_Error  error;
597     FT_ULong  old_pos;
598     FT_ULong  result = 0;
599 
600 
601     old_pos = stream->pos;
602     if ( !FT_Stream_Seek( stream, stream->size - 4 ) )
603     {
604       result = FT_Stream_ReadULongLE( stream, &error );
605       if ( error )
606         result = 0;
607 
608       (void)FT_Stream_Seek( stream, old_pos );
609     }
610 
611     return result;
612   }
613 
614 
615   /* documentation is in ftgzip.h */
616 
617   FT_EXPORT_DEF( FT_Error )
FT_Stream_OpenGzip(FT_Stream stream,FT_Stream source)618   FT_Stream_OpenGzip( FT_Stream  stream,
619                       FT_Stream  source )
620   {
621     FT_Error     error;
622     FT_Memory    memory;
623     FT_GZipFile  zip = NULL;
624 
625 
626     if ( !stream || !source )
627     {
628       error = FT_THROW( Invalid_Stream_Handle );
629       goto Exit;
630     }
631 
632     memory = source->memory;
633 
634     /*
635      * check the header right now; this prevents allocating un-necessary
636      * objects when we don't need them
637      */
638     error = ft_gzip_check_header( source );
639     if ( error )
640       goto Exit;
641 
642     FT_ZERO( stream );
643     stream->memory = memory;
644 
645     if ( !FT_QNEW( zip ) )
646     {
647       error = ft_gzip_file_init( zip, stream, source );
648       if ( error )
649       {
650         FT_FREE( zip );
651         goto Exit;
652       }
653 
654       stream->descriptor.pointer = zip;
655     }
656 
657     /*
658      * We use the following trick to try to dramatically improve the
659      * performance while dealing with small files.  If the original stream
660      * size is less than a certain threshold, we try to load the whole font
661      * file into memory.  This saves us from using the 32KB buffer needed
662      * to inflate the file, plus the two 4KB intermediate input/output
663      * buffers used in the `FT_GZipFile' structure.
664      */
665     {
666       FT_ULong  zip_size = ft_gzip_get_uncompressed_size( source );
667 
668 
669       if ( zip_size != 0 && zip_size < 40 * 1024 )
670       {
671         FT_Byte*  zip_buff = NULL;
672 
673 
674         if ( !FT_ALLOC( zip_buff, zip_size ) )
675         {
676           FT_ULong  count;
677 
678 
679           count = ft_gzip_file_io( zip, 0, zip_buff, zip_size );
680           if ( count == zip_size )
681           {
682             ft_gzip_file_done( zip );
683             FT_FREE( zip );
684 
685             stream->descriptor.pointer = NULL;
686 
687             stream->size  = zip_size;
688             stream->pos   = 0;
689             stream->base  = zip_buff;
690             stream->read  = NULL;
691             stream->close = ft_gzip_stream_close;
692 
693             goto Exit;
694           }
695 
696           ft_gzip_file_io( zip, 0, NULL, 0 );
697           FT_FREE( zip_buff );
698         }
699         error = FT_Err_Ok;
700       }
701 
702       if ( zip_size )
703         stream->size = zip_size;
704       else
705         stream->size  = 0x7FFFFFFFL;  /* don't know the real size! */
706     }
707 
708     stream->pos   = 0;
709     stream->base  = NULL;
710     stream->read  = ft_gzip_stream_io;
711     stream->close = ft_gzip_stream_close;
712 
713   Exit:
714     return error;
715   }
716 
717 
718   /* documentation is in ftgzip.h */
719 
720   FT_EXPORT_DEF( FT_Error )
FT_Gzip_Uncompress(FT_Memory memory,FT_Byte * output,FT_ULong * output_len,const FT_Byte * input,FT_ULong input_len)721   FT_Gzip_Uncompress( FT_Memory       memory,
722                       FT_Byte*        output,
723                       FT_ULong*       output_len,
724                       const FT_Byte*  input,
725                       FT_ULong        input_len )
726   {
727     z_stream  stream;
728     int       err;
729 
730 
731     /* check for `input' delayed to `inflate' */
732 
733     if ( !memory || !output_len || !output )
734       return FT_THROW( Invalid_Argument );
735 
736     /* this function is modeled after zlib's `uncompress' function */
737 
738     stream.next_in  = (Bytef*)input;
739     stream.avail_in = (uInt)input_len;
740 
741     stream.next_out  = output;
742     stream.avail_out = (uInt)*output_len;
743 
744     stream.zalloc = (alloc_func)ft_gzip_alloc;
745     stream.zfree  = (free_func) ft_gzip_free;
746     stream.opaque = memory;
747 
748     /* This is a temporary fix and will be removed once the internal
749      * copy of zlib is updated to the newest version. The `|32' flag
750      * is only supported in the new versions of zlib to enable gzip
751      * encoded header.
752      */
753 #ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB
754     err = inflateInit2( &stream, MAX_WBITS|32 );
755 #else
756     err = inflateInit2( &stream, MAX_WBITS );
757 #endif
758 
759     if ( err != Z_OK )
760       return FT_THROW( Invalid_Argument );
761 
762     err = inflate( &stream, Z_FINISH );
763     if ( err != Z_STREAM_END )
764     {
765       inflateEnd( &stream );
766       if ( err == Z_OK )
767         err = Z_BUF_ERROR;
768     }
769     else
770     {
771       *output_len = stream.total_out;
772 
773       err = inflateEnd( &stream );
774     }
775 
776     if ( err == Z_MEM_ERROR )
777       return FT_THROW( Out_Of_Memory );
778 
779     if ( err == Z_BUF_ERROR )
780       return FT_THROW( Array_Too_Large );
781 
782     if ( err == Z_DATA_ERROR )
783       return FT_THROW( Invalid_Table );
784 
785     return FT_Err_Ok;
786   }
787 
788 
789 #else /* !FT_CONFIG_OPTION_USE_ZLIB */
790 
791   FT_EXPORT_DEF( FT_Error )
FT_Stream_OpenGzip(FT_Stream stream,FT_Stream source)792   FT_Stream_OpenGzip( FT_Stream  stream,
793                       FT_Stream  source )
794   {
795     FT_UNUSED( stream );
796     FT_UNUSED( source );
797 
798     return FT_THROW( Unimplemented_Feature );
799   }
800 
801 
802   FT_EXPORT_DEF( FT_Error )
FT_Gzip_Uncompress(FT_Memory memory,FT_Byte * output,FT_ULong * output_len,const FT_Byte * input,FT_ULong input_len)803   FT_Gzip_Uncompress( FT_Memory       memory,
804                       FT_Byte*        output,
805                       FT_ULong*       output_len,
806                       const FT_Byte*  input,
807                       FT_ULong        input_len )
808   {
809     FT_UNUSED( memory );
810     FT_UNUSED( output );
811     FT_UNUSED( output_len );
812     FT_UNUSED( input );
813     FT_UNUSED( input_len );
814 
815     return FT_THROW( Unimplemented_Feature );
816   }
817 
818 #endif /* !FT_CONFIG_OPTION_USE_ZLIB */
819 
820 
821 /* END */
822