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Message port

Message port provides the high-performance interprocess communication system.

#include "windows.h"
#include "msgaccss.h"

class callback_notify : public msg_callback_notify
{
public:
	// this function for incoming messages
	virtual bool incoming_callback(msg_t* msg, msg_t* reply) 
	{ 
		return false; // return false if you don't take responsibility to destroy incoming msg
	}
	// this function for asynchronous replies
	virtual bool async_callback(msg_t* reply, size_t ident) 
	{ 
		return false; // return false if you don't take responsibility to destroy incoming reply
	}
};


int main()
{
	callback_notify notifier;
	msgaccess msg_creator;
	msg_port* port = msg_creator.get_msg_port();
	bool mres = port->init("c:\\test.xml", 0);
	mres = port->start(&notifier, 0);

	const char* msgBody = "This is a message body which can contains anything you want";
	size_t len = strlen(msgBody);
	msg_t* msg = port->construct(len + 1); // add space for zero byte
	memcpy(port->get_buffer(msg), msgBody, len + 1);
	
	guid_t receiver = {0xD8589807, 0x1D14, 0x4872, {0xB4, 0x2A, 0x51, 0xED, 0xF2, 0xEE, 0x12, 0x39}};
	mres = port->set_receiver(msg, receiver);
	msg->msgid = 1;
	msg->timeout = 1000; // 1 second timeout
	int count = 300; // send message 300 times
	while (--count)
	{
		msg_t* reply = 0;

		mres = port->send(true, // specify true, port will make a copy of message
					 msg, &reply);
		if (!mres)
		{
			// if send method returns false, caller is still responsible for msg object
			port->destroy(msg);
			msg = 0;
			break;
		}

		if (reply) // if reply is specified
		{
			// get message info here
			// for example message body
			const void* bufReply = port->get_buffer(reply);

			// then destroy reply
			port->destroy(reply);
		}
	}

	if (msg) // we still must destroy message
		port->destroy(msg);

	// stop port 
	mres = port->stop();
	// uninit port
	mres = port->uninit();
	// destroy port object
	delete port;

	return 0;
}


How does port know where the another program (port) located?
All settings come from init xml file, below the DTD for such files

<?xml version="1.0" encoding="UTF-8"?>
<!ENTITY % kind "(rpc | sock | http)">
<!ELEMENT msgPort (listeners?, connections?)>
<!ATTLIST msgPort 
address CDATA #REQUIRED >
<!ELEMENT listeners (listener)*>
<!ELEMENT connections (connection)*>
<!ELEMENT connection EMPTY>
<!ATTLIST connection
type %kind; #REQUIRED
address CDATA #REQUIRED
port CDATA #IMPLIED
network CDATA #IMPLIED
ping CDATA #IMPLIED
info CDATA #IMPLIED
security CDATA #IMPLIED
password CDATA #IMPLIED >
<!ELEMENT listener (accept | reject)?>
<!ATTLIST listener
type %kind; #REQUIRED
port CDATA #IMPLIED
connections CDATA #IMPLIED
ping CDATA #IMPLIED
info CDATA #IMPLIED
security CDATA #IMPLIED
password CDATA #IMPLIED >
<!ELEMENT reject (peer)+>
<!ELEMENT accept (peer)+>
<!ELEMENT peer EMPTY>
<!ATTLIST peer
address CDATA #REQUIRED
security CDATA #IMPLIED
password CDATA #IMPLIED >

Format of address attribute is follow:
D85898071D144872B42A51EDF2EE1239
Heximal representation of 16 bytes UUID/GUID.

Every new program MUST use new generated UUID.
Two Message Ports with the same UUID are not allowed.