Sockets: properly fix Node IPC

sockets.js

@@ -437,24 +437,28 @@ class GoWorker extends EventEmitter {
 		this.connection = connection;
 		this.connection.setEncoding('utf8');
 		this.connection.on('data', /** @param {string} data */ data => {
-			if (!data.endsWith(DELIM)) {
-				// The child process sent us a message that's too long for the
-				// TCP connection to handle receiving all at once. Buffer.
+			let idx = data.lastIndexOf(DELIM);
+			if (idx < 0) {
+				// Very long message...
 				this.ibuf += data;
 				return;
 			}
 
-			let message = (this.ibuf + data).slice(0, -1);
+			// Because of how Node handles TCP connections, we can
+			// receive any number of messages, and they may not
+			// be guaranteed to be complete.
+			let messages = this.ibuf;
 			this.ibuf = '';
-
-			// FIXME: certain client messages are screwing with Go's JSON
-			// marshaller! Better not be a SockJS bug.
-			if (message.endsWith('\uFFFD')) {
-				Monitor.log(`Sockets: received a message from the client with malformed codepoints: ${message}`);
-				message = message.slice(0, -1);
+			if (idx === data.length - 1) {
+				messages += data.slice(0, -1);
+			} else {
+				messages += data.slice(0, idx);
+				this.ibuf += data.slice(idx + 1);
 			}
 
-			this.emit('message', JSON.parse(message));
+			for (let message of messages.split(DELIM)) {
+				this.emit('message', JSON.parse(message));
+			}
 		});
 		this.connection.on('error', () => {});
 		this.connection.once('listening', () => this.emit('listening'));