Stream based filter

I am thinking to create a filter which can parse/decompress/scan partial read HTTP data. The idea is to use three buffers and implement a customized istream and ostream, both will use a customerized streambuf. In the compression process:
a). the buffer to store compressed data in the customized streambuf.
b). when overflow is called, the first buffered data sent to the de-compressor which may also buffer the data internally. When it outputs the data, it may be sent to the third buffer.
c). the user defined stream buffer.

The streambuf has a few function has to be override:
a). Overflow() in output stream: there is no space in the buffer, write it out. The data between ibegin and iend is sent to the gzip library to compress to a file
b). Underflow() in input stream: there is no more character in the buffer, read more. The data read is decrypted by call gzip library and then dump to input buffer.

An other option is to use boost::iostreams::gzip

http://www.codeproject.com/KB/stl/zipstream.aspx