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source: trunk/poppler/freetype2/src/gzip/ftgzip.c @ 262

Last change on this file since 262 was 262, checked in by Eugene Romanenko, 12 years ago
PDF plugin: freetype library updated to version 2.3.8
File size: 17.6 KB

Line
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 2002, 2003, 2004, 2005, 2006, 2009 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 <ft2build.h>
24	#include FT_INTERNAL_MEMORY_H
25	#include FT_INTERNAL_STREAM_H
26	#include FT_INTERNAL_DEBUG_H
27	#include FT_GZIP_H
28	#include FT_CONFIG_STANDARD_LIBRARY_H
29
30
31	#include FT_MODULE_ERRORS_H
32
33	#undef __FTERRORS_H__
34
35	#define FT_ERR_PREFIX Gzip_Err_
36	#define FT_ERR_BASE FT_Mod_Err_Gzip
37
38	#include FT_ERRORS_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 "ftgzip" 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	#define NO_DUMMY_DECL
57	#define MY_ZCALLOC
58
59	#include "zlib.h"
60
61	#undef SLOW
62	#define SLOW 1 /* we can't use asm-optimized sources here! */
63
64	/* Urgh. `inflate_mask' must not be declared twice -- C++ doesn't like
65	this. We temporarily disable it and load all necessary header files. */
66	#define NO_INFLATE_MASK
67	#include "zutil.h"
68	#include "inftrees.h"
69	#include "infblock.h"
70	#include "infcodes.h"
71	#include "infutil.h"
72	#undef NO_INFLATE_MASK
73
74	/* infutil.c must be included before infcodes.c */
75	#include "zutil.c"
76	#include "inftrees.c"
77	#include "infutil.c"
78	#include "infcodes.c"
79	#include "infblock.c"
80	#include "inflate.c"
81	#include "adler32.c"
82
83	#endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
84
85
86	/***************************************************************************/
87	/***************************************************************************/
88	/*** ***/
89	/*** Z L I B M E M O R Y M A N A G E M E N T ***/
90	/*** ***/
91	/***************************************************************************/
92	/***************************************************************************/
93
94	/* it is better to use FreeType memory routines instead of raw
95	'malloc/free' */
96
97	static voidpf
98	ft_gzip_alloc( FT_Memory memory,
99	uInt items,
100	uInt size )
101	{
102	FT_ULong sz = (FT_ULong)size * items;
103	FT_Error error;
104	FT_Pointer p;
105
106
107	(void)FT_ALLOC( p, sz );
108	return p;
109	}
110
111
112	static void
113	ft_gzip_free( FT_Memory memory,
114	voidpf address )
115	{
116	FT_MEM_FREE( address );
117	}
118
119
120	#ifndef FT_CONFIG_OPTION_SYSTEM_ZLIB
121
122	local voidpf
123	zcalloc ( voidpf opaque,
124	unsigned items,
125	unsigned size )
126	{
127	return ft_gzip_alloc( (FT_Memory)opaque, items, size );
128	}
129
130	local void
131	zcfree( voidpf opaque,
132	voidpf ptr )
133	{
134	ft_gzip_free( (FT_Memory)opaque, ptr );
135	}
136
137	#endif /* !SYSTEM_ZLIB */
138
139
140	/***************************************************************************/
141	/***************************************************************************/
142	/*** ***/
143	/*** Z L I B F I L E D E S C R I P T O R ***/
144	/*** ***/
145	/***************************************************************************/
146	/***************************************************************************/
147
148	#define FT_GZIP_BUFFER_SIZE 4096
149
150	typedef struct FT_GZipFileRec_
151	{
152	FT_Stream source; /* parent/source stream */
153	FT_Stream stream; /* embedding stream */
154	FT_Memory memory; /* memory allocator */
155	z_stream zstream; /* zlib input stream */
156
157	FT_ULong start; /* starting position, after .gz header */
158	FT_Byte input[FT_GZIP_BUFFER_SIZE]; /* input read buffer */
159
160	FT_Byte buffer[FT_GZIP_BUFFER_SIZE]; /* output buffer */
161	FT_ULong pos; /* position in output */
162	FT_Byte* cursor;
163	FT_Byte* limit;
164
165	} FT_GZipFileRec, *FT_GZipFile;
166
167
168	/* gzip flag byte */
169	#define FT_GZIP_ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
170	#define FT_GZIP_HEAD_CRC 0x02 /* bit 1 set: header CRC present */
171	#define FT_GZIP_EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
172	#define FT_GZIP_ORIG_NAME 0x08 /* bit 3 set: original file name present */
173	#define FT_GZIP_COMMENT 0x10 /* bit 4 set: file comment present */
174	#define FT_GZIP_RESERVED 0xE0 /* bits 5..7: reserved */
175
176
177	/* check and skip .gz header - we don't support `transparent' compression */
178	static FT_Error
179	ft_gzip_check_header( FT_Stream stream )
180	{
181	FT_Error error;
182	FT_Byte head[4];
183
184
185	if ( FT_STREAM_SEEK( 0 ) \|\|
186	FT_STREAM_READ( head, 4 ) )
187	goto Exit;
188
189	/* head[0] && head[1] are the magic numbers; */
190	/* head[2] is the method, and head[3] the flags */
191	if ( head[0] != 0x1f \|\|
192	head[1] != 0x8b \|\|
193	head[2] != Z_DEFLATED \|\|
194	(head[3] & FT_GZIP_RESERVED) )
195	{
196	error = Gzip_Err_Invalid_File_Format;
197	goto Exit;
198	}
199
200	/* skip time, xflags and os code */
201	(void)FT_STREAM_SKIP( 6 );
202
203	/* skip the extra field */
204	if ( head[3] & FT_GZIP_EXTRA_FIELD )
205	{
206	FT_UInt len;
207
208
209	if ( FT_READ_USHORT_LE( len ) \|\|
210	FT_STREAM_SKIP( len ) )
211	goto Exit;
212	}
213
214	/* skip original file name */
215	if ( head[3] & FT_GZIP_ORIG_NAME )
216	for (;;)
217	{
218	FT_UInt c;
219
220
221	if ( FT_READ_BYTE( c ) )
222	goto Exit;
223
224	if ( c == 0 )
225	break;
226	}
227
228	/* skip .gz comment */
229	if ( head[3] & FT_GZIP_COMMENT )
230	for (;;)
231	{
232	FT_UInt c;
233
234
235	if ( FT_READ_BYTE( c ) )
236	goto Exit;
237
238	if ( c == 0 )
239	break;
240	}
241
242	/* skip CRC */
243	if ( head[3] & FT_GZIP_HEAD_CRC )
244	if ( FT_STREAM_SKIP( 2 ) )
245	goto Exit;
246
247	Exit:
248	return error;
249	}
250
251
252	static FT_Error
253	ft_gzip_file_init( FT_GZipFile zip,
254	FT_Stream stream,
255	FT_Stream source )
256	{
257	z_stream* zstream = &zip->zstream;
258	FT_Error error = Gzip_Err_Ok;
259
260
261	zip->stream = stream;
262	zip->source = source;
263	zip->memory = stream->memory;
264
265	zip->limit = zip->buffer + FT_GZIP_BUFFER_SIZE;
266	zip->cursor = zip->limit;
267	zip->pos = 0;
268
269	/* check and skip .gz header */
270	{
271	stream = source;
272
273	error = ft_gzip_check_header( stream );
274	if ( error )
275	goto Exit;
276
277	zip->start = FT_STREAM_POS();
278	}
279
280	/* initialize zlib -- there is no zlib header in the compressed stream */
281	zstream->zalloc = (alloc_func)ft_gzip_alloc;
282	zstream->zfree = (free_func) ft_gzip_free;
283	zstream->opaque = stream->memory;
284
285	zstream->avail_in = 0;
286	zstream->next_in = zip->buffer;
287
288	if ( inflateInit2( zstream, -MAX_WBITS ) != Z_OK \|\|
289	zstream->next_in == NULL )
290	error = Gzip_Err_Invalid_File_Format;
291
292	Exit:
293	return error;
294	}
295
296
297	static void
298	ft_gzip_file_done( FT_GZipFile zip )
299	{
300	z_stream* zstream = &zip->zstream;
301
302
303	inflateEnd( zstream );
304
305	/* clear the rest */
306	zstream->zalloc = NULL;
307	zstream->zfree = NULL;
308	zstream->opaque = NULL;
309	zstream->next_in = NULL;
310	zstream->next_out = NULL;
311	zstream->avail_in = 0;
312	zstream->avail_out = 0;
313
314	zip->memory = NULL;
315	zip->source = NULL;
316	zip->stream = NULL;
317	}
318
319
320	static FT_Error
321	ft_gzip_file_reset( FT_GZipFile zip )
322	{
323	FT_Stream stream = zip->source;
324	FT_Error error;
325
326
327	if ( !FT_STREAM_SEEK( zip->start ) )
328	{
329	z_stream* zstream = &zip->zstream;
330
331
332	inflateReset( zstream );
333
334	zstream->avail_in = 0;
335	zstream->next_in = zip->input;
336	zstream->avail_out = 0;
337	zstream->next_out = zip->buffer;
338
339	zip->limit = zip->buffer + FT_GZIP_BUFFER_SIZE;
340	zip->cursor = zip->limit;
341	zip->pos = 0;
342	}
343
344	return error;
345	}
346
347
348	static FT_Error
349	ft_gzip_file_fill_input( FT_GZipFile zip )
350	{
351	z_stream* zstream = &zip->zstream;
352	FT_Stream stream = zip->source;
353	FT_ULong size;
354
355
356	if ( stream->read )
357	{
358	size = stream->read( stream, stream->pos, zip->input,
359	FT_GZIP_BUFFER_SIZE );
360	if ( size == 0 )
361	return Gzip_Err_Invalid_Stream_Operation;
362	}
363	else
364	{
365	size = stream->size - stream->pos;
366	if ( size > FT_GZIP_BUFFER_SIZE )
367	size = FT_GZIP_BUFFER_SIZE;
368
369	if ( size == 0 )
370	return Gzip_Err_Invalid_Stream_Operation;
371
372	FT_MEM_COPY( zip->input, stream->base + stream->pos, size );
373	}
374	stream->pos += size;
375
376	zstream->next_in = zip->input;
377	zstream->avail_in = size;
378
379	return Gzip_Err_Ok;
380	}
381
382
383	static FT_Error
384	ft_gzip_file_fill_output( FT_GZipFile zip )
385	{
386	z_stream* zstream = &zip->zstream;
387	FT_Error error = 0;
388
389
390	zip->cursor = zip->buffer;
391	zstream->next_out = zip->cursor;
392	zstream->avail_out = FT_GZIP_BUFFER_SIZE;
393
394	while ( zstream->avail_out > 0 )
395	{
396	int err;
397
398
399	if ( zstream->avail_in == 0 )
400	{
401	error = ft_gzip_file_fill_input( zip );
402	if ( error )
403	break;
404	}
405
406	err = inflate( zstream, Z_NO_FLUSH );
407
408	if ( err == Z_STREAM_END )
409	{
410	zip->limit = zstream->next_out;
411	if ( zip->limit == zip->cursor )
412	error = Gzip_Err_Invalid_Stream_Operation;
413	break;
414	}
415	else if ( err != Z_OK )
416	{
417	error = Gzip_Err_Invalid_Stream_Operation;
418	break;
419	}
420	}
421
422	return error;
423	}
424
425
426	/* fill output buffer; `count' must be <= FT_GZIP_BUFFER_SIZE */
427	static FT_Error
428	ft_gzip_file_skip_output( FT_GZipFile zip,
429	FT_ULong count )
430	{
431	FT_Error error = Gzip_Err_Ok;
432	FT_ULong delta;
433
434
435	for (;;)
436	{
437	delta = (FT_ULong)( zip->limit - zip->cursor );
438	if ( delta >= count )
439	delta = count;
440
441	zip->cursor += delta;
442	zip->pos += delta;
443
444	count -= delta;
445	if ( count == 0 )
446	break;
447
448	error = ft_gzip_file_fill_output( zip );
449	if ( error )
450	break;
451	}
452
453	return error;
454	}
455
456
457	static FT_ULong
458	ft_gzip_file_io( FT_GZipFile zip,
459	FT_ULong pos,
460	FT_Byte* buffer,
461	FT_ULong count )
462	{
463	FT_ULong result = 0;
464	FT_Error error;
465
466
467	/* Reset inflate stream if we're seeking backwards. */
468	/* Yes, that is not too efficient, but it saves memory :-) */
469	if ( pos < zip->pos )
470	{
471	error = ft_gzip_file_reset( zip );
472	if ( error )
473	goto Exit;
474	}
475
476	/* skip unwanted bytes */
477	if ( pos > zip->pos )
478	{
479	error = ft_gzip_file_skip_output( zip, (FT_ULong)( pos - zip->pos ) );
480	if ( error )
481	goto Exit;
482	}
483
484	if ( count == 0 )
485	goto Exit;
486
487	/* now read the data */
488	for (;;)
489	{
490	FT_ULong delta;
491
492
493	delta = (FT_ULong)( zip->limit - zip->cursor );
494	if ( delta >= count )
495	delta = count;
496
497	FT_MEM_COPY( buffer, zip->cursor, delta );
498	buffer += delta;
499	result += delta;
500	zip->cursor += delta;
501	zip->pos += delta;
502
503	count -= delta;
504	if ( count == 0 )
505	break;
506
507	error = ft_gzip_file_fill_output( zip );
508	if ( error )
509	break;
510	}
511
512	Exit:
513	return result;
514	}
515
516
517	/***************************************************************************/
518	/***************************************************************************/
519	/*** ***/
520	/*** G Z E M B E D D I N G S T R E A M ***/
521	/*** ***/
522	/***************************************************************************/
523	/***************************************************************************/
524
525	static void
526	ft_gzip_stream_close( FT_Stream stream )
527	{
528	FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer;
529	FT_Memory memory = stream->memory;
530
531
532	if ( zip )
533	{
534	/* finalize gzip file descriptor */
535	ft_gzip_file_done( zip );
536
537	FT_FREE( zip );
538
539	stream->descriptor.pointer = NULL;
540	}
541	}
542
543
544	static FT_ULong
545	ft_gzip_stream_io( FT_Stream stream,
546	FT_ULong pos,
547	FT_Byte* buffer,
548	FT_ULong count )
549	{
550	FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer;
551
552
553	return ft_gzip_file_io( zip, pos, buffer, count );
554	}
555
556
557	static FT_ULong
558	ft_gzip_get_uncompressed_size( FT_Stream stream )
559	{
560	FT_Error error;
561	FT_ULong old_pos;
562	FT_ULong result = 0;
563
564
565	old_pos = stream->pos;
566	if ( !FT_Stream_Seek( stream, stream->size - 4 ) )
567	{
568	result = (FT_ULong)FT_Stream_ReadLong( stream, &error );
569	if ( error )
570	result = 0;
571
572	FT_Stream_Seek( stream, old_pos );
573	}
574
575	return result;
576	}
577
578
579	FT_EXPORT_DEF( FT_Error )
580	FT_Stream_OpenGzip( FT_Stream stream,
581	FT_Stream source )
582	{
583	FT_Error error;
584	FT_Memory memory = source->memory;
585	FT_GZipFile zip;
586
587
588	/*
589	* check the header right now; this prevents allocating un-necessary
590	* objects when we don't need them
591	*/
592	error = ft_gzip_check_header( source );
593	if ( error )
594	goto Exit;
595
596	FT_ZERO( stream );
597	stream->memory = memory;
598
599	if ( !FT_QNEW( zip ) )
600	{
601	error = ft_gzip_file_init( zip, stream, source );
602	if ( error )
603	{
604	FT_FREE( zip );
605	goto Exit;
606	}
607
608	stream->descriptor.pointer = zip;
609	}
610
611	/*
612	* We use the following trick to try to dramatically improve the
613	* performance while dealing with small files. If the original stream
614	* size is less than a certain threshold, we try to load the whole font
615	* file into memory. This saves us from using the 32KB buffer needed
616	* to inflate the file, plus the two 4KB intermediate input/output
617	* buffers used in the `FT_GZipFile' structure.
618	*/
619	{
620	FT_ULong zip_size = ft_gzip_get_uncompressed_size( source );
621
622
623	if ( zip_size != 0 && zip_size < 40 * 1024 )
624	{
625	FT_Byte* zip_buff;
626
627
628	if ( !FT_ALLOC( zip_buff, zip_size ) )
629	{
630	FT_ULong count;
631
632
633	count = ft_gzip_file_io( zip, 0, zip_buff, zip_size );
634	if ( count == zip_size )
635	{
636	ft_gzip_file_done( zip );
637	FT_FREE( zip );
638
639	stream->descriptor.pointer = NULL;
640
641	stream->size = zip_size;
642	stream->pos = 0;
643	stream->base = zip_buff;
644	stream->read = NULL;
645	stream->close = ft_gzip_stream_close;
646
647	goto Exit;
648	}
649
650	ft_gzip_file_io( zip, 0, NULL, 0 );
651	FT_FREE( zip_buff );
652	}
653	error = 0;
654	}
655	}
656
657	stream->size = 0x7FFFFFFFL; /* don't know the real size! */
658	stream->pos = 0;
659	stream->base = 0;
660	stream->read = ft_gzip_stream_io;
661	stream->close = ft_gzip_stream_close;
662
663	Exit:
664	return error;
665	}
666
667	#else /* !FT_CONFIG_OPTION_USE_ZLIB */
668
669	FT_EXPORT_DEF( FT_Error )
670	FT_Stream_OpenGzip( FT_Stream stream,
671	FT_Stream source )
672	{
673	FT_UNUSED( stream );
674	FT_UNUSED( source );
675
676	return Gzip_Err_Unimplemented_Feature;
677	}
678
679	#endif /* !FT_CONFIG_OPTION_USE_ZLIB */
680
681
682	/* END */

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