1 /***************************************************************************/
5 /* FreeType support for .gz compressed files. */
7 /* This optional component relies on zlib. It should mainly be used to */
8 /* parse compressed PCF fonts, as found with many X11 server */
11 /* Copyright 2002-2006, 2009-2011 by */
12 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
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. */
20 /***************************************************************************/
24 #include FT_INTERNAL_MEMORY_H
25 #include FT_INTERNAL_STREAM_H
26 #include FT_INTERNAL_DEBUG_H
28 #include FT_CONFIG_STANDARD_LIBRARY_H
31 #include FT_MODULE_ERRORS_H
35 #define FT_ERR_PREFIX Gzip_Err_
36 #define FT_ERR_BASE FT_Mod_Err_Gzip
41 #ifdef FT_CONFIG_OPTION_USE_ZLIB
43 #ifdef FT_CONFIG_OPTION_PIC
44 #error "gzip code does not support PIC yet"
47 #ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB
51 #else /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
53 /* In this case, we include our own modified sources of the ZLib */
54 /* within the "ftgzip" component. The modifications were necessary */
55 /* to #include all files without conflicts, as well as preventing */
56 /* the definition of "extern" functions that may cause linking */
57 /* conflicts when a program is linked with both FreeType and the */
61 #ifndef USE_ZLIB_ZCALLOC
62 #define MY_ZCALLOC /* prevent all zcalloc() & zfree() in zutils.c */
68 #define SLOW 1 /* we can't use asm-optimized sources here! */
70 /* Urgh. `inflate_mask' must not be declared twice -- C++ doesn't like
71 this. We temporarily disable it and load all necessary header files. */
72 #define NO_INFLATE_MASK
78 #undef NO_INFLATE_MASK
80 /* infutil.c must be included before infcodes.c */
89 #endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */
92 /***************************************************************************/
93 /***************************************************************************/
95 /***** Z L I B M E M O R Y M A N A G E M E N T *****/
97 /***************************************************************************/
98 /***************************************************************************/
100 /* it is better to use FreeType memory routines instead of raw
104 ft_gzip_alloc( FT_Memory memory,
108 FT_ULong sz = (FT_ULong)size * items;
113 (void)FT_ALLOC( p, sz );
119 ft_gzip_free( FT_Memory memory,
122 FT_MEM_FREE( address );
126 #if !defined( FT_CONFIG_OPTION_SYSTEM_ZLIB ) && !defined( USE_ZLIB_ZCALLOC )
129 zcalloc ( voidpf opaque,
133 return ft_gzip_alloc( (FT_Memory)opaque, items, size );
137 zcfree( voidpf opaque,
140 ft_gzip_free( (FT_Memory)opaque, ptr );
143 #endif /* !SYSTEM_ZLIB && !USE_ZLIB_ZCALLOC */
146 /***************************************************************************/
147 /***************************************************************************/
149 /***** Z L I B F I L E D E S C R I P T O R *****/
151 /***************************************************************************/
152 /***************************************************************************/
154 #define FT_GZIP_BUFFER_SIZE 4096
156 typedef struct FT_GZipFileRec_
158 FT_Stream source; /* parent/source stream */
159 FT_Stream stream; /* embedding stream */
160 FT_Memory memory; /* memory allocator */
161 z_stream zstream; /* zlib input stream */
163 FT_ULong start; /* starting position, after .gz header */
164 FT_Byte input[FT_GZIP_BUFFER_SIZE]; /* input read buffer */
166 FT_Byte buffer[FT_GZIP_BUFFER_SIZE]; /* output buffer */
167 FT_ULong pos; /* position in output */
171 } FT_GZipFileRec, *FT_GZipFile;
175 #define FT_GZIP_ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */
176 #define FT_GZIP_HEAD_CRC 0x02 /* bit 1 set: header CRC present */
177 #define FT_GZIP_EXTRA_FIELD 0x04 /* bit 2 set: extra field present */
178 #define FT_GZIP_ORIG_NAME 0x08 /* bit 3 set: original file name present */
179 #define FT_GZIP_COMMENT 0x10 /* bit 4 set: file comment present */
180 #define FT_GZIP_RESERVED 0xE0 /* bits 5..7: reserved */
183 /* check and skip .gz header - we don't support `transparent' compression */
185 ft_gzip_check_header( FT_Stream stream )
191 if ( FT_STREAM_SEEK( 0 ) ||
192 FT_STREAM_READ( head, 4 ) )
195 /* head[0] && head[1] are the magic numbers; */
196 /* head[2] is the method, and head[3] the flags */
197 if ( head[0] != 0x1f ||
199 head[2] != Z_DEFLATED ||
200 (head[3] & FT_GZIP_RESERVED) )
202 error = Gzip_Err_Invalid_File_Format;
206 /* skip time, xflags and os code */
207 (void)FT_STREAM_SKIP( 6 );
209 /* skip the extra field */
210 if ( head[3] & FT_GZIP_EXTRA_FIELD )
215 if ( FT_READ_USHORT_LE( len ) ||
216 FT_STREAM_SKIP( len ) )
220 /* skip original file name */
221 if ( head[3] & FT_GZIP_ORIG_NAME )
227 if ( FT_READ_BYTE( c ) )
234 /* skip .gz comment */
235 if ( head[3] & FT_GZIP_COMMENT )
241 if ( FT_READ_BYTE( c ) )
249 if ( head[3] & FT_GZIP_HEAD_CRC )
250 if ( FT_STREAM_SKIP( 2 ) )
259 ft_gzip_file_init( FT_GZipFile zip,
263 z_stream* zstream = &zip->zstream;
264 FT_Error error = Gzip_Err_Ok;
267 zip->stream = stream;
268 zip->source = source;
269 zip->memory = stream->memory;
271 zip->limit = zip->buffer + FT_GZIP_BUFFER_SIZE;
272 zip->cursor = zip->limit;
275 /* check and skip .gz header */
279 error = ft_gzip_check_header( stream );
283 zip->start = FT_STREAM_POS();
286 /* initialize zlib -- there is no zlib header in the compressed stream */
287 zstream->zalloc = (alloc_func)ft_gzip_alloc;
288 zstream->zfree = (free_func) ft_gzip_free;
289 zstream->opaque = stream->memory;
291 zstream->avail_in = 0;
292 zstream->next_in = zip->buffer;
294 if ( inflateInit2( zstream, -MAX_WBITS ) != Z_OK ||
295 zstream->next_in == NULL )
296 error = Gzip_Err_Invalid_File_Format;
304 ft_gzip_file_done( FT_GZipFile zip )
306 z_stream* zstream = &zip->zstream;
309 inflateEnd( zstream );
312 zstream->zalloc = NULL;
313 zstream->zfree = NULL;
314 zstream->opaque = NULL;
315 zstream->next_in = NULL;
316 zstream->next_out = NULL;
317 zstream->avail_in = 0;
318 zstream->avail_out = 0;
327 ft_gzip_file_reset( FT_GZipFile zip )
329 FT_Stream stream = zip->source;
333 if ( !FT_STREAM_SEEK( zip->start ) )
335 z_stream* zstream = &zip->zstream;
338 inflateReset( zstream );
340 zstream->avail_in = 0;
341 zstream->next_in = zip->input;
342 zstream->avail_out = 0;
343 zstream->next_out = zip->buffer;
345 zip->limit = zip->buffer + FT_GZIP_BUFFER_SIZE;
346 zip->cursor = zip->limit;
355 ft_gzip_file_fill_input( FT_GZipFile zip )
357 z_stream* zstream = &zip->zstream;
358 FT_Stream stream = zip->source;
364 size = stream->read( stream, stream->pos, zip->input,
365 FT_GZIP_BUFFER_SIZE );
367 return Gzip_Err_Invalid_Stream_Operation;
371 size = stream->size - stream->pos;
372 if ( size > FT_GZIP_BUFFER_SIZE )
373 size = FT_GZIP_BUFFER_SIZE;
376 return Gzip_Err_Invalid_Stream_Operation;
378 FT_MEM_COPY( zip->input, stream->base + stream->pos, size );
382 zstream->next_in = zip->input;
383 zstream->avail_in = size;
390 ft_gzip_file_fill_output( FT_GZipFile zip )
392 z_stream* zstream = &zip->zstream;
393 FT_Error error = Gzip_Err_Ok;
396 zip->cursor = zip->buffer;
397 zstream->next_out = zip->cursor;
398 zstream->avail_out = FT_GZIP_BUFFER_SIZE;
400 while ( zstream->avail_out > 0 )
405 if ( zstream->avail_in == 0 )
407 error = ft_gzip_file_fill_input( zip );
412 err = inflate( zstream, Z_NO_FLUSH );
414 if ( err == Z_STREAM_END )
416 zip->limit = zstream->next_out;
417 if ( zip->limit == zip->cursor )
418 error = Gzip_Err_Invalid_Stream_Operation;
421 else if ( err != Z_OK )
423 error = Gzip_Err_Invalid_Stream_Operation;
432 /* fill output buffer; `count' must be <= FT_GZIP_BUFFER_SIZE */
434 ft_gzip_file_skip_output( FT_GZipFile zip,
437 FT_Error error = Gzip_Err_Ok;
443 delta = (FT_ULong)( zip->limit - zip->cursor );
444 if ( delta >= count )
447 zip->cursor += delta;
454 error = ft_gzip_file_fill_output( zip );
464 ft_gzip_file_io( FT_GZipFile zip,
473 /* Reset inflate stream if we're seeking backwards. */
474 /* Yes, that is not too efficient, but it saves memory :-) */
475 if ( pos < zip->pos )
477 error = ft_gzip_file_reset( zip );
482 /* skip unwanted bytes */
483 if ( pos > zip->pos )
485 error = ft_gzip_file_skip_output( zip, (FT_ULong)( pos - zip->pos ) );
493 /* now read the data */
499 delta = (FT_ULong)( zip->limit - zip->cursor );
500 if ( delta >= count )
503 FT_MEM_COPY( buffer, zip->cursor, delta );
506 zip->cursor += delta;
513 error = ft_gzip_file_fill_output( zip );
523 /***************************************************************************/
524 /***************************************************************************/
526 /***** G Z E M B E D D I N G S T R E A M *****/
528 /***************************************************************************/
529 /***************************************************************************/
532 ft_gzip_stream_close( FT_Stream stream )
534 FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer;
535 FT_Memory memory = stream->memory;
540 /* finalize gzip file descriptor */
541 ft_gzip_file_done( zip );
545 stream->descriptor.pointer = NULL;
551 ft_gzip_stream_io( FT_Stream stream,
556 FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer;
559 return ft_gzip_file_io( zip, pos, buffer, count );
564 ft_gzip_get_uncompressed_size( FT_Stream stream )
571 old_pos = stream->pos;
572 if ( !FT_Stream_Seek( stream, stream->size - 4 ) )
574 result = FT_Stream_ReadULong( stream, &error );
578 (void)FT_Stream_Seek( stream, old_pos );
585 FT_EXPORT_DEF( FT_Error )
586 FT_Stream_OpenGzip( FT_Stream stream,
590 FT_Memory memory = source->memory;
591 FT_GZipFile zip = NULL;
595 * check the header right now; this prevents allocating un-necessary
596 * objects when we don't need them
598 error = ft_gzip_check_header( source );
603 stream->memory = memory;
605 if ( !FT_QNEW( zip ) )
607 error = ft_gzip_file_init( zip, stream, source );
614 stream->descriptor.pointer = zip;
618 * We use the following trick to try to dramatically improve the
619 * performance while dealing with small files. If the original stream
620 * size is less than a certain threshold, we try to load the whole font
621 * file into memory. This saves us from using the 32KB buffer needed
622 * to inflate the file, plus the two 4KB intermediate input/output
623 * buffers used in the `FT_GZipFile' structure.
626 FT_ULong zip_size = ft_gzip_get_uncompressed_size( source );
629 if ( zip_size != 0 && zip_size < 40 * 1024 )
631 FT_Byte* zip_buff = NULL;
634 if ( !FT_ALLOC( zip_buff, zip_size ) )
639 count = ft_gzip_file_io( zip, 0, zip_buff, zip_size );
640 if ( count == zip_size )
642 ft_gzip_file_done( zip );
645 stream->descriptor.pointer = NULL;
647 stream->size = zip_size;
649 stream->base = zip_buff;
651 stream->close = ft_gzip_stream_close;
656 ft_gzip_file_io( zip, 0, NULL, 0 );
663 stream->size = 0x7FFFFFFFL; /* don't know the real size! */
666 stream->read = ft_gzip_stream_io;
667 stream->close = ft_gzip_stream_close;
673 #else /* !FT_CONFIG_OPTION_USE_ZLIB */
675 FT_EXPORT_DEF( FT_Error )
676 FT_Stream_OpenGzip( FT_Stream stream,
682 return Gzip_Err_Unimplemented_Feature;
685 #endif /* !FT_CONFIG_OPTION_USE_ZLIB */