wsock is WebSocket library for libmill

*wsock wsocklisten(ipaddr addr, const char subprotocol, int backlog);

Start listening for connections from clients. Subprotocol is a comma-delimited list of supported subprotocols. Incoming connections that don't match any of the listed subprotocols will be silently dropped. If it is set to NULL, all connections will be accepted.

wsock wsockaccept(wsock s, int64_t deadline);

Accept new connection from a client.

**wsock wsockconnect(ipaddr addr, const char subprotocol, const char url, int64_t deadline);

Connect to a server. Subprotocol is a comma-delimited list of supported subprotocols. Put preferred protocols before less preferred ones. Server will choose one of the subprotocols -- to find out which one, use wsocksubprotocol() function. Setting subprotocol to NULL means that the server is free to choose any subprotocol.

*const char wsockurl(wsock s);

After accepting a connection, you can retrieve the URL requested by peer using this function.

*const char wsocksubprotocol(wsock s);

Get subprotocol the socket is using. If you've specified multiple subprotocols with wsocklisten() or wsockconnect(), this function lets you know which one of them was chosen to be used.

*size_t wsocksend(wsock s, const void msg, size_t len, int64_t deadline);

Send a message to the peer.

*size_t wsockrecv(wsock s, void msg, size_t len, int64_t deadline);

Receive a message from the peer.

void wsockping(wsock s, int64_t deadline);

Send ping to the peer. Peer replies with pong, which will cause wsockrecv() to exit with errno set to EAGAIN.

void wsockpong(wsock s, int64_t deadline);

Send pong to the peer. It can be used to implement unsolicited one-way heartbeats.

void wsockdone(wsock s, int64_t deadline);

Start the closing handshake. After calling this function you can't send any more messages, however, you can still receive pending messages from the peer.

void wsockclose(wsock s);

Close the connection without doing the closing handshake.