ref: 90ccab3d785e9567200a585e82883007a69d7fea
dir: /src/bzip2/ftbzip2.c/
/***************************************************************************/ /* */ /* ftbzip2.c */ /* */ /* FreeType support for .bz2 compressed files. */ /* */ /* This optional component relies on libbz2. It should mainly be used to */ /* parse compressed PCF fonts, as found with many X11 server */ /* distributions. */ /* */ /* Copyright 2010-2017 by */ /* Joel Klinghed. */ /* */ /* based on `src/gzip/ftgzip.c' */ /* */ /* 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_BZIP2_H #include FT_CONFIG_STANDARD_LIBRARY_H #include FT_MODULE_ERRORS_H #undef FTERRORS_H_ #undef FT_ERR_PREFIX #define FT_ERR_PREFIX Bzip2_Err_ #define FT_ERR_BASE FT_Mod_Err_Bzip2 #include FT_ERRORS_H #ifdef FT_CONFIG_OPTION_USE_BZIP2 #ifdef FT_CONFIG_OPTION_PIC #error "bzip2 code does not support PIC yet" #endif #define BZ_NO_STDIO /* Do not need FILE */ #include <bzlib.h> /***************************************************************************/ /***************************************************************************/ /***** *****/ /***** B Z I P 2 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' */ typedef void *(* alloc_func)(void*, int, int); typedef void (* free_func)(void*, void*); static void* ft_bzip2_alloc( FT_Memory memory, int items, int size ) { FT_ULong sz = (FT_ULong)size * (FT_ULong)items; FT_Error error; FT_Pointer p = NULL; (void)FT_ALLOC( p, sz ); return p; } static void ft_bzip2_free( FT_Memory memory, void* address ) { FT_MEM_FREE( address ); } /***************************************************************************/ /***************************************************************************/ /***** *****/ /***** B Z I P 2 F I L E D E S C R I P T O R *****/ /***** *****/ /***************************************************************************/ /***************************************************************************/ #define FT_BZIP2_BUFFER_SIZE 4096 typedef struct FT_BZip2FileRec_ { FT_Stream source; /* parent/source stream */ FT_Stream stream; /* embedding stream */ FT_Memory memory; /* memory allocator */ bz_stream bzstream; /* bzlib input stream */ FT_Byte input[FT_BZIP2_BUFFER_SIZE]; /* input read buffer */ FT_Byte buffer[FT_BZIP2_BUFFER_SIZE]; /* output buffer */ FT_ULong pos; /* position in output */ FT_Byte* cursor; FT_Byte* limit; } FT_BZip2FileRec, *FT_BZip2File; /* check and skip .bz2 header - we don't support `transparent' compression */ static FT_Error ft_bzip2_check_header( FT_Stream stream ) { FT_Error error = FT_Err_Ok; 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 version, and head[3] the blocksize */ if ( head[0] != 0x42 || head[1] != 0x5A || head[2] != 0x68 ) /* only support bzip2 (huffman) */ { error = FT_THROW( Invalid_File_Format ); goto Exit; } Exit: return error; } static FT_Error ft_bzip2_file_init( FT_BZip2File zip, FT_Stream stream, FT_Stream source ) { bz_stream* bzstream = &zip->bzstream; FT_Error error = FT_Err_Ok; zip->stream = stream; zip->source = source; zip->memory = stream->memory; zip->limit = zip->buffer + FT_BZIP2_BUFFER_SIZE; zip->cursor = zip->limit; zip->pos = 0; /* check .bz2 header */ { stream = source; error = ft_bzip2_check_header( stream ); if ( error ) goto Exit; if ( FT_STREAM_SEEK( 0 ) ) goto Exit; } /* initialize bzlib */ bzstream->bzalloc = (alloc_func)ft_bzip2_alloc; bzstream->bzfree = (free_func) ft_bzip2_free; bzstream->opaque = zip->memory; bzstream->avail_in = 0; bzstream->next_in = (char*)zip->buffer; if ( BZ2_bzDecompressInit( bzstream, 0, 0 ) != BZ_OK || !bzstream->next_in ) error = FT_THROW( Invalid_File_Format ); Exit: return error; } static void ft_bzip2_file_done( FT_BZip2File zip ) { bz_stream* bzstream = &zip->bzstream; BZ2_bzDecompressEnd( bzstream ); /* clear the rest */ bzstream->bzalloc = NULL; bzstream->bzfree = NULL; bzstream->opaque = NULL; bzstream->next_in = NULL; bzstream->next_out = NULL; bzstream->avail_in = 0; bzstream->avail_out = 0; zip->memory = NULL; zip->source = NULL; zip->stream = NULL; } static FT_Error ft_bzip2_file_reset( FT_BZip2File zip ) { FT_Stream stream = zip->source; FT_Error error; if ( !FT_STREAM_SEEK( 0 ) ) { bz_stream* bzstream = &zip->bzstream; BZ2_bzDecompressEnd( bzstream ); bzstream->avail_in = 0; bzstream->next_in = (char*)zip->input; bzstream->avail_out = 0; bzstream->next_out = (char*)zip->buffer; zip->limit = zip->buffer + FT_BZIP2_BUFFER_SIZE; zip->cursor = zip->limit; zip->pos = 0; BZ2_bzDecompressInit( bzstream, 0, 0 ); } return error; } static FT_Error ft_bzip2_file_fill_input( FT_BZip2File zip ) { bz_stream* bzstream = &zip->bzstream; FT_Stream stream = zip->source; FT_ULong size; if ( stream->read ) { size = stream->read( stream, stream->pos, zip->input, FT_BZIP2_BUFFER_SIZE ); if ( size == 0 ) { zip->limit = zip->cursor; return FT_THROW( Invalid_Stream_Operation ); } } else { size = stream->size - stream->pos; if ( size > FT_BZIP2_BUFFER_SIZE ) size = FT_BZIP2_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; bzstream->next_in = (char*)zip->input; bzstream->avail_in = size; return FT_Err_Ok; } static FT_Error ft_bzip2_file_fill_output( FT_BZip2File zip ) { bz_stream* bzstream = &zip->bzstream; FT_Error error = FT_Err_Ok; zip->cursor = zip->buffer; bzstream->next_out = (char*)zip->cursor; bzstream->avail_out = FT_BZIP2_BUFFER_SIZE; while ( bzstream->avail_out > 0 ) { int err; if ( bzstream->avail_in == 0 ) { error = ft_bzip2_file_fill_input( zip ); if ( error ) break; } err = BZ2_bzDecompress( bzstream ); if ( err == BZ_STREAM_END ) { zip->limit = (FT_Byte*)bzstream->next_out; if ( zip->limit == zip->cursor ) error = FT_THROW( Invalid_Stream_Operation ); break; } else if ( err != BZ_OK ) { zip->limit = zip->cursor; error = FT_THROW( Invalid_Stream_Operation ); break; } } return error; } /* fill output buffer; `count' must be <= FT_BZIP2_BUFFER_SIZE */ static FT_Error ft_bzip2_file_skip_output( FT_BZip2File zip, FT_ULong count ) { FT_Error error = FT_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_bzip2_file_fill_output( zip ); if ( error ) break; } return error; } static FT_ULong ft_bzip2_file_io( FT_BZip2File 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_bzip2_file_reset( zip ); if ( error ) goto Exit; } /* skip unwanted bytes */ if ( pos > zip->pos ) { error = ft_bzip2_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_bzip2_file_fill_output( zip ); if ( error ) break; } Exit: return result; } /***************************************************************************/ /***************************************************************************/ /***** *****/ /***** B Z E M B E D D I N G S T R E A M *****/ /***** *****/ /***************************************************************************/ /***************************************************************************/ static void ft_bzip2_stream_close( FT_Stream stream ) { FT_BZip2File zip = (FT_BZip2File)stream->descriptor.pointer; FT_Memory memory = stream->memory; if ( zip ) { /* finalize bzip file descriptor */ ft_bzip2_file_done( zip ); FT_FREE( zip ); stream->descriptor.pointer = NULL; } } static unsigned long ft_bzip2_stream_io( FT_Stream stream, unsigned long offset, unsigned char* buffer, unsigned long count ) { FT_BZip2File zip = (FT_BZip2File)stream->descriptor.pointer; return ft_bzip2_file_io( zip, offset, buffer, count ); } FT_EXPORT_DEF( FT_Error ) FT_Stream_OpenBzip2( FT_Stream stream, FT_Stream source ) { FT_Error error; FT_Memory memory; FT_BZip2File zip = NULL; if ( !stream || !source ) { error = FT_THROW( Invalid_Stream_Handle ); goto Exit; } memory = source->memory; /* * check the header right now; this prevents allocating unnecessary * objects when we don't need them */ error = ft_bzip2_check_header( source ); if ( error ) goto Exit; FT_ZERO( stream ); stream->memory = memory; if ( !FT_QNEW( zip ) ) { error = ft_bzip2_file_init( zip, stream, source ); if ( error ) { FT_FREE( zip ); goto Exit; } stream->descriptor.pointer = zip; } stream->size = 0x7FFFFFFFL; /* don't know the real size! */ stream->pos = 0; stream->base = 0; stream->read = ft_bzip2_stream_io; stream->close = ft_bzip2_stream_close; Exit: return error; } #else /* !FT_CONFIG_OPTION_USE_BZIP2 */ FT_EXPORT_DEF( FT_Error ) FT_Stream_OpenBzip2( FT_Stream stream, FT_Stream source ) { FT_UNUSED( stream ); FT_UNUSED( source ); return FT_THROW( Unimplemented_Feature ); } #endif /* !FT_CONFIG_OPTION_USE_BZIP2 */ /* END */