PicoHTTPParser is a tiny, primitive, fast HTTP request/response parser.
Unlike most parsers, it is stateless and does not allocate memory by itself. All it does is accept pointer to buffer and the output structure, and setups the pointers in the latter to point at the necessary portions of the buffer.
The code is widely deployed within Perl applications though popular modules that use it, including Plack, Starman, Starlet, Furl.
Check out [test.c] to find out how to use the parser.