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 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 );
}
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;
}
