From a8f02e0d3734bf3f2ba2f157630e05923175173b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C5=99emysl=20Janouch?= <p@janouch.name>
Date: Sun, 22 Jul 2018 14:55:15 +0200
Subject: [PATCH] tls-autodetect: finish inQ overrun handling

---
 prototypes/tls-autodetect.go | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/prototypes/tls-autodetect.go b/prototypes/tls-autodetect.go
index aaff3d9..3ff4128 100644
--- a/prototypes/tls-autodetect.go
+++ b/prototypes/tls-autodetect.go
@@ -218,12 +218,18 @@ func (c *client) onPrepared(host string, isTLS bool) {
 	}
 
 	// TODO: Save the host in the client structure.
+	// TODO: If we've tried to send any data before now, we need to flushOutQ.
 	go read(c)
 	c.reading = true
 }
 
 // Handle the results from trying to read from the client connection.
 func (c *client) onRead(data []byte, readErr error) {
+	if !c.reading {
+		// Abusing the flag to emulate CloseRead and skip over data, see below.
+		return
+	}
+
 	c.inQ = append(c.inQ, data...)
 	for {
 		advance, token, _ := bufio.ScanLines(c.inQ, false /* atEOF */)
@@ -237,14 +243,6 @@ func (c *client) onRead(data []byte, readErr error) {
 		broadcast(line, c)
 	}
 
-	// TODO: Inform the client about the inQ overrun in the farewell message.
-	// TODO: We should stop receiving any more data from this client, or at
-	// least stop extending the inQ if we don't want to signal tho goroutine.
-	if len(c.inQ) > 8192 {
-		c.closeLink()
-		return
-	}
-
 	if readErr != nil {
 		c.reading = false
 
@@ -259,11 +257,20 @@ func (c *client) onRead(data []byte, readErr error) {
 			log.Println("client EOF")
 			c.closeLink()
 		}
+	} else if len(c.inQ) > 8192 {
+		log.Println("client inQ overrun")
+		// TODO: Inform the client about inQ overrun in the farewell message.
+		c.closeLink()
+
+		// tls.Conn doesn't have the CloseRead method (and it needs to be able
+		// to read from the TCP connection even for writes, so there isn't much
+		// sense in expecting the implementation to do anything useful),
+		// otherwise we'd use it to block incoming packet data.
+		c.reading = false
 	}
 }
 
-// Spawn a goroutine to flush the outQ if possible and necessary.  If the
-// connection is not ready yet, it needs to be retried as soon as it becomes.
+// Spawn a goroutine to flush the outQ if possible and necessary.
 func (c *client) flushOutQ() {
 	if !c.writing && c.conn != nil {
 		go write(c, c.outQ)