diff options
Diffstat (limited to 'src/gzip/ftgzip.c')
| -rw-r--r-- | src/gzip/ftgzip.c | 682 |
1 files changed, 682 insertions, 0 deletions
diff --git a/src/gzip/ftgzip.c b/src/gzip/ftgzip.c new file mode 100644 index 0000000..af2022d --- /dev/null +++ b/src/gzip/ftgzip.c @@ -0,0 +1,682 @@ +/***************************************************************************/ +/* */ +/* ftgzip.c */ +/* */ +/* FreeType support for .gz compressed files. */ +/* */ +/* This optional component relies on zlib. It should mainly be used to */ +/* parse compressed PCF fonts, as found with many X11 server */ +/* distributions. */ +/* */ +/* Copyright 2002, 2003, 2004, 2005, 2006 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 FT_INTERNAL_MEMORY_H +#include FT_INTERNAL_STREAM_H +#include FT_INTERNAL_DEBUG_H +#include FT_GZIP_H +#include <string.h> + + +#include FT_MODULE_ERRORS_H + +#undef __FTERRORS_H__ + +#define FT_ERR_PREFIX Gzip_Err_ +#define FT_ERR_BASE FT_Mod_Err_Gzip + +#include FT_ERRORS_H + + +#ifdef FT_CONFIG_OPTION_USE_ZLIB + +#ifdef FT_CONFIG_OPTION_SYSTEM_ZLIB + +#include <zlib.h> + +#else /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */ + + /* In this case, we include our own modified sources of the ZLib */ + /* within the "ftgzip" component. The modifications were necessary */ + /* to #include all files without conflicts, as well as preventing */ + /* the definition of "extern" functions that may cause linking */ + /* conflicts when a program is linked with both FreeType and the */ + /* original ZLib. */ + +#define NO_DUMMY_DECL +#define MY_ZCALLOC + +#include "zlib.h" + +#undef SLOW +#define SLOW 1 /* we can't use asm-optimized sources here! */ + + /* Urgh. `inflate_mask' must not be declared twice -- C++ doesn't like + this. We temporarily disable it and load all necessary header files. */ +#define NO_INFLATE_MASK +#include "zutil.h" +#include "inftrees.h" +#include "infblock.h" +#include "infcodes.h" +#include "infutil.h" +#undef NO_INFLATE_MASK + + /* infutil.c must be included before infcodes.c */ +#include "zutil.c" +#include "inftrees.c" +#include "infutil.c" +#include "infcodes.c" +#include "infblock.c" +#include "inflate.c" +#include "adler32.c" + +#endif /* !FT_CONFIG_OPTION_SYSTEM_ZLIB */ + + +/***************************************************************************/ +/***************************************************************************/ +/***** *****/ +/***** Z L I B M E M O R Y M A N A G E M E N T *****/ +/***** *****/ +/***************************************************************************/ +/***************************************************************************/ + + /* it is better to use FreeType memory routines instead of raw + 'malloc/free' */ + + static voidpf + ft_gzip_alloc( FT_Memory memory, + uInt items, + uInt size ) + { + FT_ULong sz = (FT_ULong)size * items; + FT_Error error; + FT_Pointer p; + + + (void)FT_ALLOC( p, sz ); + return p; + } + + + static void + ft_gzip_free( FT_Memory memory, + voidpf address ) + { + FT_MEM_FREE( address ); + } + + +#ifndef FT_CONFIG_OPTION_SYSTEM_ZLIB + + local voidpf + zcalloc ( voidpf opaque, + unsigned items, + unsigned size ) + { + return ft_gzip_alloc( (FT_Memory)opaque, items, size ); + } + + local void + zcfree( voidpf opaque, + voidpf ptr ) + { + ft_gzip_free( (FT_Memory)opaque, ptr ); + } + +#endif /* !SYSTEM_ZLIB */ + + +/***************************************************************************/ +/***************************************************************************/ +/***** *****/ +/***** Z L I B F I L E D E S C R I P T O R *****/ +/***** *****/ +/***************************************************************************/ +/***************************************************************************/ + +#define FT_GZIP_BUFFER_SIZE 4096 + + typedef struct FT_GZipFileRec_ + { + FT_Stream source; /* parent/source stream */ + FT_Stream stream; /* embedding stream */ + FT_Memory memory; /* memory allocator */ + z_stream zstream; /* zlib input stream */ + + FT_ULong start; /* starting position, after .gz header */ + FT_Byte input[FT_GZIP_BUFFER_SIZE]; /* input read buffer */ + + FT_Byte buffer[FT_GZIP_BUFFER_SIZE]; /* output buffer */ + FT_ULong pos; /* position in output */ + FT_Byte* cursor; + FT_Byte* limit; + + } FT_GZipFileRec, *FT_GZipFile; + + + /* gzip flag byte */ +#define FT_GZIP_ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ +#define FT_GZIP_HEAD_CRC 0x02 /* bit 1 set: header CRC present */ +#define FT_GZIP_EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ +#define FT_GZIP_ORIG_NAME 0x08 /* bit 3 set: original file name present */ +#define FT_GZIP_COMMENT 0x10 /* bit 4 set: file comment present */ +#define FT_GZIP_RESERVED 0xE0 /* bits 5..7: reserved */ + + + /* check and skip .gz header - we don't support `transparent' compression */ + static FT_Error + ft_gzip_check_header( FT_Stream stream ) + { + FT_Error error; + FT_Byte head[4]; + + + if ( FT_STREAM_SEEK( 0 ) || + FT_STREAM_READ( head, 4 ) ) + goto Exit; + + /* head[0] && head[1] are the magic numbers; */ + /* head[2] is the method, and head[3] the flags */ + if ( head[0] != 0x1f || + head[1] != 0x8b || + head[2] != Z_DEFLATED || + (head[3] & FT_GZIP_RESERVED) ) + { + error = Gzip_Err_Invalid_File_Format; + goto Exit; + } + + /* skip time, xflags and os code */ + (void)FT_STREAM_SKIP( 6 ); + + /* skip the extra field */ + if ( head[3] & FT_GZIP_EXTRA_FIELD ) + { + FT_UInt len; + + + if ( FT_READ_USHORT_LE( len ) || + FT_STREAM_SKIP( len ) ) + goto Exit; + } + + /* skip original file name */ + if ( head[3] & FT_GZIP_ORIG_NAME ) + for (;;) + { + FT_UInt c; + + + if ( FT_READ_BYTE( c ) ) + goto Exit; + + if ( c == 0 ) + break; + } + + /* skip .gz comment */ + if ( head[3] & FT_GZIP_COMMENT ) + for (;;) + { + FT_UInt c; + + + if ( FT_READ_BYTE( c ) ) + goto Exit; + + if ( c == 0 ) + break; + } + + /* skip CRC */ + if ( head[3] & FT_GZIP_HEAD_CRC ) + if ( FT_STREAM_SKIP( 2 ) ) + goto Exit; + + Exit: + return error; + } + + + static FT_Error + ft_gzip_file_init( FT_GZipFile zip, + FT_Stream stream, + FT_Stream source ) + { + z_stream* zstream = &zip->zstream; + FT_Error error = Gzip_Err_Ok; + + + zip->stream = stream; + zip->source = source; + zip->memory = stream->memory; + + zip->limit = zip->buffer + FT_GZIP_BUFFER_SIZE; + zip->cursor = zip->limit; + zip->pos = 0; + + /* check and skip .gz header */ + { + stream = source; + + error = ft_gzip_check_header( stream ); + if ( error ) + goto Exit; + + zip->start = FT_STREAM_POS(); + } + + /* initialize zlib -- there is no zlib header in the compressed stream */ + zstream->zalloc = (alloc_func)ft_gzip_alloc; + zstream->zfree = (free_func) ft_gzip_free; + zstream->opaque = stream->memory; + + zstream->avail_in = 0; + zstream->next_in = zip->buffer; + + if ( inflateInit2( zstream, -MAX_WBITS ) != Z_OK || + zstream->next_in == NULL ) + error = Gzip_Err_Invalid_File_Format; + + Exit: + return error; + } + + + static void + ft_gzip_file_done( FT_GZipFile zip ) + { + z_stream* zstream = &zip->zstream; + + + inflateEnd( zstream ); + + /* clear the rest */ + zstream->zalloc = NULL; + zstream->zfree = NULL; + zstream->opaque = NULL; + zstream->next_in = NULL; + zstream->next_out = NULL; + zstream->avail_in = 0; + zstream->avail_out = 0; + + zip->memory = NULL; + zip->source = NULL; + zip->stream = NULL; + } + + + static FT_Error + ft_gzip_file_reset( FT_GZipFile zip ) + { + FT_Stream stream = zip->source; + FT_Error error; + + + if ( !FT_STREAM_SEEK( zip->start ) ) + { + z_stream* zstream = &zip->zstream; + + + inflateReset( zstream ); + + zstream->avail_in = 0; + zstream->next_in = zip->input; + zstream->avail_out = 0; + zstream->next_out = zip->buffer; + + zip->limit = zip->buffer + FT_GZIP_BUFFER_SIZE; + zip->cursor = zip->limit; + zip->pos = 0; + } + + return error; + } + + + static FT_Error + ft_gzip_file_fill_input( FT_GZipFile zip ) + { + z_stream* zstream = &zip->zstream; + FT_Stream stream = zip->source; + FT_ULong size; + + + if ( stream->read ) + { + size = stream->read( stream, stream->pos, zip->input, + FT_GZIP_BUFFER_SIZE ); + if ( size == 0 ) + return Gzip_Err_Invalid_Stream_Operation; + } + else + { + size = stream->size - stream->pos; + if ( size > FT_GZIP_BUFFER_SIZE ) + size = FT_GZIP_BUFFER_SIZE; + + if ( size == 0 ) + return Gzip_Err_Invalid_Stream_Operation; + + FT_MEM_COPY( zip->input, stream->base + stream->pos, size ); + } + stream->pos += size; + + zstream->next_in = zip->input; + zstream->avail_in = size; + + return Gzip_Err_Ok; + } + + + static FT_Error + ft_gzip_file_fill_output( FT_GZipFile zip ) + { + z_stream* zstream = &zip->zstream; + FT_Error error = 0; + + + zip->cursor = zip->buffer; + zstream->next_out = zip->cursor; + zstream->avail_out = FT_GZIP_BUFFER_SIZE; + + while ( zstream->avail_out > 0 ) + { + int err; + + + if ( zstream->avail_in == 0 ) + { + error = ft_gzip_file_fill_input( zip ); + if ( error ) + break; + } + + err = inflate( zstream, Z_NO_FLUSH ); + + if ( err == Z_STREAM_END ) + { + zip->limit = zstream->next_out; + if ( zip->limit == zip->cursor ) + error = Gzip_Err_Invalid_Stream_Operation; + break; + } + else if ( err != Z_OK ) + { + error = Gzip_Err_Invalid_Stream_Operation; + break; + } + } + + return error; + } + + + /* fill output buffer; `count' must be <= FT_GZIP_BUFFER_SIZE */ + static FT_Error + ft_gzip_file_skip_output( FT_GZipFile zip, + FT_ULong count ) + { + FT_Error error = Gzip_Err_Ok; + FT_ULong delta; + + + for (;;) + { + delta = (FT_ULong)( zip->limit - zip->cursor ); + if ( delta >= count ) + delta = count; + + zip->cursor += delta; + zip->pos += delta; + + count -= delta; + if ( count == 0 ) + break; + + error = ft_gzip_file_fill_output( zip ); + if ( error ) + break; + } + + return error; + } + + + static FT_ULong + ft_gzip_file_io( FT_GZipFile zip, + FT_ULong pos, + FT_Byte* buffer, + FT_ULong count ) + { + FT_ULong result = 0; + FT_Error error; + + + /* Reset inflate stream if we're seeking backwards. */ + /* Yes, that is not too efficient, but it saves memory :-) */ + if ( pos < zip->pos ) + { + error = ft_gzip_file_reset( zip ); + if ( error ) + goto Exit; + } + + /* skip unwanted bytes */ + if ( pos > zip->pos ) + { + error = ft_gzip_file_skip_output( zip, (FT_ULong)( pos - zip->pos ) ); + if ( error ) + goto Exit; + } + + if ( count == 0 ) + goto Exit; + + /* now read the data */ + for (;;) + { + FT_ULong delta; + + + delta = (FT_ULong)( zip->limit - zip->cursor ); + if ( delta >= count ) + delta = count; + + FT_MEM_COPY( buffer, zip->cursor, delta ); + buffer += delta; + result += delta; + zip->cursor += delta; + zip->pos += delta; + + count -= delta; + if ( count == 0 ) + break; + + error = ft_gzip_file_fill_output( zip ); + if ( error ) + break; + } + + Exit: + return result; + } + + +/***************************************************************************/ +/***************************************************************************/ +/***** *****/ +/***** G Z E M B E D D I N G S T R E A M *****/ +/***** *****/ +/***************************************************************************/ +/***************************************************************************/ + + static void + ft_gzip_stream_close( FT_Stream stream ) + { + FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer; + FT_Memory memory = stream->memory; + + + if ( zip ) + { + /* finalize gzip file descriptor */ + ft_gzip_file_done( zip ); + + FT_FREE( zip ); + + stream->descriptor.pointer = NULL; + } + } + + + static FT_ULong + ft_gzip_stream_io( FT_Stream stream, + FT_ULong pos, + FT_Byte* buffer, + FT_ULong count ) + { + FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer; + + + return ft_gzip_file_io( zip, pos, buffer, count ); + } + + + static FT_ULong + ft_gzip_get_uncompressed_size( FT_Stream stream ) + { + FT_Error error; + FT_ULong old_pos; + FT_ULong result = 0; + + + old_pos = stream->pos; + if ( !FT_Stream_Seek( stream, stream->size - 4 ) ) + { + result = (FT_ULong)FT_Stream_ReadLong( stream, &error ); + if ( error ) + result = 0; + + FT_Stream_Seek( stream, old_pos ); + } + + return result; + } + + + FT_EXPORT_DEF( FT_Error ) + FT_Stream_OpenGzip( FT_Stream stream, + FT_Stream source ) + { + FT_Error error; + FT_Memory memory = source->memory; + FT_GZipFile zip; + + + /* + * check the header right now; this prevents allocating un-necessary + * objects when we don't need them + */ + error = ft_gzip_check_header( source ); + if ( error ) + goto Exit; + + FT_ZERO( stream ); + stream->memory = memory; + + if ( !FT_QNEW( zip ) ) + { + error = ft_gzip_file_init( zip, stream, source ); + if ( error ) + { + FT_FREE( zip ); + goto Exit; + } + + stream->descriptor.pointer = zip; + } + + /* + * We use the following trick to try to dramatically improve the + * performance while dealing with small files. If the original stream + * size is less than a certain threshold, we try to load the whole font + * file into memory. This saves us from using the 32KB buffer needed + * to inflate the file, plus the two 4KB intermediate input/output + * buffers used in the `FT_GZipFile' structure. + */ + { + FT_ULong zip_size = ft_gzip_get_uncompressed_size( source ); + + + if ( zip_size != 0 && zip_size < 40 * 1024 ) + { + FT_Byte* zip_buff; + + + if ( !FT_ALLOC( zip_buff, zip_size ) ) + { + FT_ULong count; + + + count = ft_gzip_file_io( zip, 0, zip_buff, zip_size ); + if ( count == zip_size ) + { + ft_gzip_file_done( zip ); + FT_FREE( zip ); + + stream->descriptor.pointer = NULL; + + stream->size = zip_size; + stream->pos = 0; + stream->base = zip_buff; + stream->read = NULL; + stream->close = ft_gzip_stream_close; + + goto Exit; + } + + ft_gzip_file_io( zip, 0, NULL, 0 ); + FT_FREE( zip_buff ); + } + error = 0; + } + } + + stream->size = 0x7FFFFFFFL; /* don't know the real size! */ + stream->pos = 0; + stream->base = 0; + stream->read = ft_gzip_stream_io; + stream->close = ft_gzip_stream_close; + + Exit: + return error; + } + +#else /* !FT_CONFIG_OPTION_USE_ZLIB */ + + FT_EXPORT_DEF( FT_Error ) + FT_Stream_OpenGzip( FT_Stream stream, + FT_Stream source ) + { + FT_UNUSED( stream ); + FT_UNUSED( source ); + + return Gzip_Err_Unimplemented_Feature; + } + +#endif /* !FT_CONFIG_OPTION_USE_ZLIB */ + + +/* END */ |