Multiplayer client/server system -- Message base class, "hello" message, and message class test harness

src/Server/message.cxx

@@ -22,6 +22,8 @@
 
 #include "message.hxx"
 
+FGMPSInstanceFuncMap	FGMPSMessage::funcmap;
+
 FGMPSMessage::FGMPSMessage() 
 {
 	msgid = 0x0000;
@@ -30,5 +32,118 @@ FGMPSMessage::FGMPSMessage()
 	
 }
 
+string FGMPSMessage::encodemsg()
+{
+	FGMPSMsgElementEntry* ptr = getelements();
+
+	buf.clr();
+	if (msgid > 255) {
+		buf.put(fgmps_som16, true);
+		buf.write2(&msgid);
+	} else {
+		buf.put(fgmps_som8, true);
+		buf.write1(&msgid);
+	}
+	while (ptr->type != fgmps_null) {
+		buf.put(ptr->type, true);
+		//printf ("adding %02x\n", ptr->type);
+		switch (ptr->type) {
+		case fgmps_uchar:
+		case fgmps_char:
+			buf.write1(ptr->data);
+			break;
+		case fgmps_uint:
+		case fgmps_int:
+			buf.write2(ptr->data);
+			break;
+		case fgmps_ulong:
+		case fgmps_long:
+			buf.write4(ptr->data);
+			break;
+		case fgmps_float:
+			buf.writef(*(float*)ptr->data);
+			break;
+		case fgmps_double:
+			buf.writed(*(double*)ptr->data);
+			break;
+		case fgmps_string:
+			buf.writes(*(string*)ptr->data);
+			break;
+		}
+		ptr++;
+	}
+
+	buf.put(fgmps_eom, true);
+
+	return buf.str();
+}
+
+FGMPSMessage* FGMPSMessage::decodemsg(string msg)
+{
+	FGMPSMessageBuf			buf;
+	unsigned char			ch;
+	unsigned int			mid;
+	FGMPSInstanceFuncMap::iterator	fmitr;
+
+	buf.set(msg);
+	buf.ofs(0);
+	ch = buf.get(true);
+	if (ch != fgmps_som8 && ch != fgmps_som16) {
+		throw FGMPSDataException("Invalid start of message");
+	}
+	if (ch == fgmps_som8) {
+		ch = buf.get();
+		mid = ch;
+	} else {
+		mid = *(unsigned int *)buf.read2();
+	}
+	
+	fmitr = funcmap.find(mid);
+	if (fmitr == funcmap.end()) {
+		throw FGMPSDataException("MessageID has no registered Message Class");
+	}
+	FGMPSMessage* msgclass = (fmitr->second)();
+	FGMPSMsgElementEntry* elements = msgclass->getelements();
+	while ((ch = buf.get()) != fgmps_eom) {
+		//printf("dump: ");
+		//for (int i=-1; i<16; i++) printf("%02x ", buf.peek(i));
+		//printf("\n");
+
+		if (ch != elements->type) {
+			delete msgclass;
+			throw FGMPSDataException("Decode: Message Structure Error");
+		}
+		switch (ch) {
+		case fgmps_uchar:
+		case fgmps_char:
+			memcpy(elements->data, buf.read1(), 1);
+			break;
+		case fgmps_uint:
+		case fgmps_int:
+			memcpy(elements->data, buf.read2(), 2);
+			break;
+		case fgmps_ulong:
+		case fgmps_long:
+			memcpy(elements->data, buf.read4(), 4);
+			break;
+		case fgmps_float:
+			*(float*)elements->data = buf.readf();
+			break;
+		case fgmps_double:
+			*(double*)elements->data = buf.readd();
+			break;
+		case fgmps_string:
+			ch = buf.get();
+			*(string*)elements->data = buf.reads(ch);
+			break;
+		default:
+			delete msgclass;
+			throw FGMPSDataException("Decode: Unknown data type");
+			break;
+		}
+		elements++;
+	}
+	return msgclass;
+}
 
 

src/Server/message.hxx

@@ -27,9 +27,11 @@
 
 #include STL_STRING
 #include <stdexcept>
+#include <map>
 
 SG_USING_STD(string);
 SG_USING_STD(invalid_argument);
+SG_USING_STD(map);
 
 #include "messagebuf.hxx"
 
@@ -62,22 +64,35 @@ typedef struct
 
 #define FGMPSMsgElementArrayEnd {fgmps_null, 0}
 
+class FGMPSMessage;
+
+typedef FGMPSMessage* FGMPSMessagePtr;
+typedef FGMPSMessagePtr (*FGMPSMsgInstanceFunc)(void);
+
+typedef map<unsigned int, FGMPSMsgInstanceFunc> FGMPSInstanceFuncMap;
+
 class FGMPSMessage
 {
 private:
+	static FGMPSInstanceFuncMap	funcmap;
 	FGMPSMsgElementEntry 		elements[1];
-	static unsigned int		msgid;
 protected:
-	FGMPSMessageBuf			msg;
+	FGMPSMessageBuf		buf;
+	unsigned int		msgid;
 public:
+	static int registermsg(int msgid, FGMPSMsgInstanceFunc func)
+	{
+		funcmap[msgid] = func;
+	}
+
 	FGMPSMessage();
 	~FGMPSMessage() {}
 
-	virtual string			encodemsg() {}
+	string			encodemsg();
-	virtual FGMPSMessage*		decodemsg(string msg) {}
+	static FGMPSMessage*	decodemsg(string msg);
-	virtual FGMPSMsgElementEntry*	getelements() { return elements; }
+	unsigned int		getmessageid() { return msgid; }
-	virtual unsigned int		getmessageid() { return msgid; }
 
+	virtual FGMPSMsgElementEntry*	getelements() { return elements; }
 };
 
 #endif

src/Server/msg_0001_hello.cxx

@@ -24,11 +24,11 @@
 
 FGMPSMsg0001Hello::FGMPSMsg0001Hello() 
 {
-	msgid = 0x0001;
+	msgid = FGMPSMsg0001HelloID;
-	elements[0].type = fgmps_uint;		elements[0].data = &this->vermajor;	
+	elements[0].type = fgmps_uint;		elements[0].data = &vermajor;	
-	elements[1].type = fgmps_uint;		elements[0].data = &this->verminor;	
+	elements[1].type = fgmps_uint;		elements[1].data = &verminor;	
-	elements[2].type = fgmps_uint;		elements[0].data = &this->verpatch;	
+	elements[2].type = fgmps_uint;		elements[2].data = &verpatch;	
-	elements[3].type = fgmps_string;	elements[0].data = &this->servname;	
+	elements[3].type = fgmps_string;	elements[3].data = &servname;	
 	elements[4].type = fgmps_null;		elements[4].data = NULL;	
 }
 

src/Server/msg_0001_hello.hxx

@@ -25,20 +25,26 @@
 
 #include "message.hxx"
 
-class FGMPSMsg0001Hello
+#define FGMPSMsg0001HelloID 0x0001
+
+class FGMPSMsg0001Hello: public FGMPSMessage
 {
 private:
 	FGMPSMsgElementEntry	 	elements[5];
-	unsigned int			msgid;
 public:
+
+	static void registerme() 
+	{ 
+		FGMPSMessage::registermsg(FGMPSMsg0001HelloID, &FGMPSMsg0001Hello::instance);
+	}
+
+	static FGMPSMessage* instance() { return (FGMPSMessage*) new FGMPSMsg0001Hello; }
+
+	virtual FGMPSMsgElementEntry*	getelements() { return elements; }
+
 	FGMPSMsg0001Hello();
 	~FGMPSMsg0001Hello() {}
 
-	virtual string			encodemsg() {}
-	virtual FGMPSMessage*		decodemsg(string msg) {}
-	virtual FGMPSMsgElementEntry*	getelements() { return elements; }
-	virtual unsigned int		getmessageid() { return msgid; }
-
 	unsigned int	vermajor;
 	unsigned int	verminor;
 	unsigned int	verpatch;

src/Server/msgtest.cxx

@@ -1,6 +1,40 @@
-#include "messagebuf.hxx"
+#include "msg_0001_hello.hxx"
 
 main(int argc, char **argv)
 {
-	printf("Hello\n");
+	string			str;
+	FGMPSMsg0001Hello	msg1, *msg2;
+
+	FGMPSMsg0001Hello::registerme();
+
+	msg1.vermajor = 3;
+	msg1.verminor = 7;
+	msg1.verpatch = 42;
+	msg1.servname = "test";
+
+	str = msg1.encodemsg();
+
+	printf("Message ID = %ui\n", msg1.getmessageid());
+	printf("major = %u\n", msg1.vermajor);
+	printf("minor = %u\n", msg1.verminor);
+	printf("patch = %u\n", msg1.verpatch);
+	printf("sname = %s\n", msg1.servname.c_str());
+
+	printf("dump: ");
+	for (int i=0; i<str.length(); i++) printf("%02x ", (unsigned char)str[i]);
+	printf("\n");
+
+	try {
+		msg2 = (FGMPSMsg0001Hello*)FGMPSMessage::decodemsg(str);
+	} catch (FGMPSDataException e) {
+		printf("Exception: %s\n", e.what());
+		exit(1);
+	}
+
+	printf("Message ID = %u\n", msg2->getmessageid());
+	printf("major = %u\n", msg2->vermajor);
+	printf("minor = %u\n", msg2->verminor);
+	printf("patch = %u\n", msg2->verpatch);
+	printf("sname = %s\n", msg2->servname.c_str());
+	
 }