Safe-ify net module, and extend functionality.

- Custom bind address for outgoing stream connections
- reusePort flag
- Full OutputStream interface for TCPConnection.

source/vibe/core/net.d

@@ -17,6 +17,8 @@ import vibe.core.stream;
 import vibe.internal.async;
 import core.time : Duration;
 
+@safe:
+
 
 /**
 	Resolves the given host name/IP address string.
@@ -43,8 +45,8 @@ NetworkAddress resolveHost(string host, ushort address_family, bool use_dns = tr
 		ret.family = addr.addressFamily;
 		switch (addr.addressFamily) with(AddressFamily) {
 			default: throw new Exception("Unsupported address family");
-			case INET: *ret.sockAddrInet4 = *cast(sockaddr_in*)addr.name; break;
+			case INET: *ret.sockAddrInet4 = () @trusted { return *cast(sockaddr_in*)addr.name; } (); break;
-			case INET6: *ret.sockAddrInet6 = *cast(sockaddr_in6*)addr.name; break;
+			case INET6: *ret.sockAddrInet6 = () @trusted { return *cast(sockaddr_in6*)addr.name; } (); break;
 		}
 		return ret;
 	} else {
@@ -85,6 +87,7 @@ TCPListener listenTCP(ushort port, TCPConnectionDelegate connection_callback, st
 {
 	auto addr = resolveHost(address);
 	addr.port = port;
+	assert(options == TCPListenOptions.defaults, "TODO");
 	auto sock = eventDriver.sockets.listenStream(addr.toUnknownAddress, (StreamListenSocketFD ls, StreamSocketFD s) @safe nothrow {
 		import vibe.core.core : runTask;
 		runTask(connection_callback, TCPConnection(s));
@@ -110,26 +113,54 @@ TCPListener listenTCP_s(ushort port, TCPConnectionFunction connection_callback,
 /**
 	Establishes a connection to the given host/port.
 */
-TCPConnection connectTCP(string host, ushort port)
+TCPConnection connectTCP(string host, ushort port, string bind_interface = null, ushort bind_port = 0)
 {
 	NetworkAddress addr = resolveHost(host);
 	addr.port = port;
-	return connectTCP(addr);
+	if (addr.family != AddressFamily.UNIX)
+		addr.port = port;
+
+	NetworkAddress bind_address;
+	if (bind_interface.length) bind_address = resolveHost(bind_interface, addr.family);
+	else {
+		bind_address.family = addr.family;
+		if (bind_address.family == AddressFamily.INET) bind_address.sockAddrInet4.sin_addr.s_addr = 0;
+		else if (bind_address.family != AddressFamily.UNIX) bind_address.sockAddrInet6.sin6_addr.s6_addr[] = 0;
+	}
+	if (addr.family != AddressFamily.UNIX)
+		bind_address.port = bind_port;
+
+	return connectTCP(addr, bind_address);
 }
 /// ditto
-TCPConnection connectTCP(NetworkAddress addr)
+TCPConnection connectTCP(NetworkAddress addr, NetworkAddress bind_address = anyAddress)
 {
 	import std.conv : to;
 
-	scope uaddr = new UnknownAddress;
+	if (bind_address.family == AddressFamily.UNSPEC) {
-	addr.toUnknownAddress(uaddr);
+		bind_address.family = addr.family;
-	// FIXME: make this interruptible
+		if (bind_address.family == AddressFamily.INET) bind_address.sockAddrInet4.sin_addr.s_addr = 0;
-	auto result = asyncAwaitUninterruptible!(ConnectCallback, 
+		else if (bind_address.family != AddressFamily.UNIX) bind_address.sockAddrInet6.sin6_addr.s6_addr[] = 0;
-		cb => eventDriver.sockets.connectStream(uaddr, cb)
+		if (bind_address.family != AddressFamily.UNIX)
-		//cb => eventDriver.sockets.cancelConnect(cb)
+			bind_address.port = 0;
-	);
+	}
-	enforce(result[1] == ConnectStatus.connected, "Failed to connect to "~addr.toString()~": "~result[1].to!string);
+	enforce(addr.family == bind_address.family, "Destination address and bind address have different address families.");
-	return TCPConnection(result[0]);
+
+	return () @trusted { // scope
+		scope uaddr = new UnknownAddress;
+		addr.toUnknownAddress(uaddr);
+
+		scope baddr = new UnknownAddress;
+		bind_address.toUnknownAddress(baddr);
+		
+		// FIXME: make this interruptible
+		auto result = asyncAwaitUninterruptible!(ConnectCallback, 
+			cb => eventDriver.sockets.connectStream(uaddr, baddr, cb)
+			//cb => eventDriver.sockets.cancelConnect(cb)
+		);
+		enforce(result[1] == ConnectStatus.connected, "Failed to connect to "~addr.toString()~": "~result[1].to!string);
+		return TCPConnection(result[0]);
+	} ();
 }
 
 
@@ -143,6 +174,13 @@ UDPConnection listenUDP(ushort port, string bind_address = "0.0.0.0")
 	return UDPConnection(addr);
 }
 
+NetworkAddress anyAddress()
+{
+	NetworkAddress ret;
+	ret.family = AddressFamily.UNSPEC;
+	return ret;
+}
+
 
 /// Callback invoked for incoming TCP connections.
 @safe nothrow alias TCPConnectionDelegate = void delegate(TCPConnection stream);
@@ -365,6 +403,8 @@ struct TCPConnection {
 			eventDriver.sockets.releaseRef(m_socket);
 	}
 
+	bool opCast(T)() const nothrow if (is(T == bool)) { return m_socket != StreamSocketFD.invalid; }
+
 	@property void tcpNoDelay(bool enabled) { eventDriver.sockets.setTCPNoDelay(m_socket, enabled); }
 	@property bool tcpNoDelay() const { assert(false); }
 	@property void keepAlive(bool enable) { assert(false); }
@@ -466,6 +506,9 @@ mixin(tracer);
 		}
 	}
 
+	void write(in char[] bytes) { write(cast(const(ubyte)[])bytes); }
+	void write(InputStream stream) { write(stream, 0); }
+
 	void flush() {
 mixin(tracer);
 	}
@@ -518,6 +561,8 @@ struct TCPListener {
 		m_socket = socket;
 	}
 
+	bool opCast(T)() const nothrow if (is(T == bool)) { return m_socket != StreamListenSocketFD.invalid; }
+
 	/// The local address at which TCP connections are accepted.
 	@property NetworkAddress bindAddress()
 	{
@@ -558,6 +603,7 @@ struct UDPConnection {
 			eventDriver.sockets.releaseRef(m_socket);
 	}
 
+	bool opCast(T)() const nothrow if (is(T == bool)) { return m_socket != DatagramSocketFD.invalid; }
 
 	/** Returns the address to which the UDP socket is bound.
 	*/
@@ -637,6 +683,10 @@ enum TCPListenOptions {
 	distribute = 1<<0,
 	/// Disables automatic closing of the connection when the connection callback exits
 	disableAutoClose = 1<<1,
+	/** Enable port reuse on linux kernel version >=3.9, do nothing on other OS
+	    Does not affect libasync driver because it is always enabled by libasync.
+	*/
+	reusePort = 1<<2,
 }
 
 private pure nothrow {