Edit
kc3-lang/freetype/src/gzip/ftgzip.c
Alexei Podtelezhnikov
- src/gzip/ftgzip.c
-
/**************************************************************************** * * 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 (C) 2002-2024 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 <freetype/internal/ftmemory.h> #include <freetype/internal/ftstream.h> #include <freetype/internal/ftdebug.h> #include <freetype/ftgzip.h> #include FT_CONFIG_STANDARD_LIBRARY_H #include <freetype/ftmoderr.h> #undef FTERRORS_H_ #undef FT_ERR_PREFIX #define FT_ERR_PREFIX Gzip_Err_ #define FT_ERR_BASE FT_Mod_Err_Gzip #include <freetype/fterrors.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 `gzip' 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. */ #ifndef USE_ZLIB_ZCALLOC #define MY_ZCALLOC /* prevent all zcalloc() & zfree() in zutil.c */ #endif /* Note that our `zlib.h' includes `ftzconf.h' instead of `zconf.h'; */ /* the main reason is that even a global `zlib.h' includes `zconf.h' */ /* with */ /* */ /* #include "zconf.h" */ /* */ /* instead of the expected */ /* */ /* #include <zconf.h> */ /* */ /* so that configuration with `FT_CONFIG_OPTION_SYSTEM_ZLIB' might */ /* include the wrong `zconf.h' file, leading to errors. */ #define ZEXPORT /* prevent zlib functions from being visible outside their object files */ #define ZEXTERN static #define HAVE_MEMCPY 1 #define Z_SOLO 1 #define Z_FREETYPE 1 #if defined( _MSC_VER ) /* Visual C++ (and Intel C++) */ /* We disable the warning `conversion from XXX to YYY, */ /* possible loss of data' in order to compile cleanly with */ /* the maximum level of warnings: zlib is non-FreeType */ /* code. */ #pragma warning( push ) #pragma warning( disable : 4244 ) #endif /* _MSC_VER */ #if defined( __GNUC__ ) #pragma GCC diagnostic push #ifndef __cplusplus #pragma GCC diagnostic ignored "-Wstrict-prototypes" #endif #pragma GCC diagnostic ignored "-Wimplicit-fallthrough" #pragma GCC diagnostic ignored "-Wredundant-decls" #endif #include "zutil.c" #include "inffast.c" #include "inflate.c" #include "inftrees.c" #include "adler32.c" #include "crc32.c" #if defined( __GNUC__ ) #pragma GCC diagnostic pop #endif #if defined( _MSC_VER ) #pragma warning( pop ) #endif #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( voidpf opaque, uInt items, uInt size ) { FT_Memory memory = (FT_Memory)opaque; FT_ULong sz = (FT_ULong)size * items; FT_Error error; FT_Pointer p = NULL; /* allocate and zero out */ FT_MEM_ALLOC( p, sz ); return p; } static void ft_gzip_free( voidpf opaque, voidpf address ) { FT_Memory memory = (FT_Memory)opaque; FT_MEM_FREE( address ); } /***************************************************************************/ /***************************************************************************/ /***** *****/ /***** 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 = FT_THROW( 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 = FT_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 = ft_gzip_alloc; zstream->zfree = 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 ) error = FT_THROW( 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 ) { zip->limit = zip->cursor; return FT_THROW( Invalid_Stream_Operation ); } } else { size = stream->size - stream->pos; if ( size > FT_GZIP_BUFFER_SIZE ) size = FT_GZIP_BUFFER_SIZE; if ( size == 0 ) { zip->limit = zip->cursor; return FT_THROW( 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 FT_Err_Ok; } static FT_Error ft_gzip_file_fill_output( FT_GZipFile zip ) { z_stream* zstream = &zip->zstream; FT_Error error = FT_Err_Ok; 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 = FT_THROW( Invalid_Stream_Operation ); break; } else if ( err != Z_OK ) { zip->limit = zip->cursor; error = FT_THROW( 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 = FT_Err_Ok; for (;;) { FT_ULong 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; } if ( !stream->read ) FT_FREE( stream->base ); } static unsigned long ft_gzip_stream_io( FT_Stream stream, unsigned long offset, unsigned char* buffer, unsigned long count ) { FT_GZipFile zip = (FT_GZipFile)stream->descriptor.pointer; return ft_gzip_file_io( zip, offset, 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_Stream_ReadULongLE( stream, &error ); if ( error ) result = 0; (void)FT_Stream_Seek( stream, old_pos ); } return result; } /* documentation is in ftgzip.h */ FT_EXPORT_DEF( FT_Error ) FT_Stream_OpenGzip( FT_Stream stream, FT_Stream source ) { FT_Error error; FT_Memory memory; FT_GZipFile zip = NULL; if ( !stream || !source ) { error = FT_THROW( Invalid_Stream_Handle ); goto Exit; } memory = source->memory; /* * 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 = NULL; if ( !FT_QALLOC( 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 = FT_Err_Ok; } if ( zip_size ) stream->size = zip_size; else stream->size = 0x7FFFFFFFL; /* don't know the real size! */ } stream->pos = 0; stream->base = NULL; stream->read = ft_gzip_stream_io; stream->close = ft_gzip_stream_close; Exit: return error; } /* documentation is in ftgzip.h */ 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 ) { z_stream stream; int err; /* check for `input' delayed to `inflate' */ if ( !memory || !output_len || !output ) return FT_THROW( Invalid_Argument ); /* this function is modeled after zlib's `uncompress' function */ stream.next_in = (Bytef*)input; stream.avail_in = (uInt)input_len; stream.next_out = output; stream.avail_out = (uInt)*output_len; stream.zalloc = ft_gzip_alloc; stream.zfree = ft_gzip_free; stream.opaque = memory; err = inflateInit2( &stream, MAX_WBITS|32 ); if ( err != Z_OK ) return FT_THROW( Invalid_Argument ); err = inflate( &stream, Z_FINISH ); if ( err != Z_STREAM_END ) { inflateEnd( &stream ); if ( err == Z_OK ) err = Z_BUF_ERROR; } else { *output_len = stream.total_out; err = inflateEnd( &stream ); } if ( err == Z_MEM_ERROR ) return FT_THROW( Out_Of_Memory ); if ( err == Z_BUF_ERROR ) return FT_THROW( Array_Too_Large ); if ( err == Z_DATA_ERROR ) return FT_THROW( Invalid_Table ); if ( err == Z_NEED_DICT ) return FT_THROW( Invalid_Table ); return FT_Err_Ok; } #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 FT_THROW( Unimplemented_Feature ); } 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 ) { FT_UNUSED( memory ); FT_UNUSED( output ); FT_UNUSED( output_len ); FT_UNUSED( input ); FT_UNUSED( input_len ); return FT_THROW( Unimplemented_Feature ); } #endif /* !FT_CONFIG_OPTION_USE_ZLIB */ /* END */