Fossil SCM

A clone or sync over HTTP/HTTPS could block when the peer stopped sending without closing the connection. The client sat in a blocking read on the socket with no timeout. The trick was to fix it without breaking the TLS handshake.

http_socket.c: set SO_RCVTIMEO and SO_SNDTIMEO (30s) on the connection socket. The fd stays in blocking mode so the TLS handshake is unaffected.

http_ssl.c: when reads time out with SO_RCVTIMEO, there is no data and BIO_should_retry() is true. Count consecutive retries without progress in ssl_send()/ssl_receive() and give up after a few.