From 7356d4e60b689fc098b55f02ae3d7688e166194f Mon Sep 17 00:00:00 2001
From: Pierre Ossman <ossman@cendio.se>
Date: Sun, 21 May 2023 20:16:59 +0200
Subject: [PATCH] Move WebSocket queue index reset to receive

It's more robust to do this just before we need the space, rather than
assume when the queue will be read and adjust things right after.
---
 core/websock.js       | 12 ++++++------
 tests/test.websock.js | 11 +++++------
 2 files changed, 11 insertions(+), 12 deletions(-)

diff --git a/core/websock.js b/core/websock.js
index 711ea02b..75be044a 100644
--- a/core/websock.js
+++ b/core/websock.js
@@ -308,6 +308,12 @@ export default class Websock {
 
     // push arraybuffer values onto the end of the receive que
     _recvMessage(e) {
+        if (this._rQlen == this._rQi) {
+            // All data has now been processed, this means we
+            // can reset the receive queue.
+            this._rQlen = 0;
+            this._rQi = 0;
+        }
         const u8 = new Uint8Array(e.data);
         if (u8.length > this._rQbufferSize - this._rQlen) {
             this._expandCompactRQ(u8.length);
@@ -317,12 +323,6 @@ export default class Websock {
 
         if (this._rQlen - this._rQi > 0) {
             this._eventHandlers.message();
-            if (this._rQlen == this._rQi) {
-                // All data has now been processed, this means we
-                // can reset the receive queue.
-                this._rQlen = 0;
-                this._rQi = 0;
-            }
         } else {
             Log.Debug("Ignoring empty message");
         }
diff --git a/tests/test.websock.js b/tests/test.websock.js
index de7fe0d1..f3cc4224 100644
--- a/tests/test.websock.js
+++ b/tests/test.websock.js
@@ -418,14 +418,13 @@ describe('Websock', function () {
             expect(sock._eventHandlers.message).not.to.have.been.called;
         });
 
-        it('should compact the receive queue when a message handler empties it', function () {
-            sock._eventHandlers.message = () => { sock._rQi = sock._rQlen; };
+        it('should compact the receive queue when fully read', function () {
             sock._rQ = new Uint8Array([0, 1, 2, 3, 4, 5, 0, 0, 0, 0]);
             sock._rQlen = 6;
             sock._rQi = 6;
             const msg = { data: new Uint8Array([1, 2, 3]).buffer };
             sock._recvMessage(msg);
-            expect(sock._rQlen).to.equal(0);
+            expect(sock._rQlen).to.equal(3);
             expect(sock._rQi).to.equal(0);
         });
 
@@ -455,13 +454,13 @@ describe('Websock', function () {
         it('should automatically resize the receive queue if the incoming message is larger than 1/8th of the buffer and we reach the end of the buffer', function () {
             sock._rQ = new Uint8Array(20);
             sock._rQlen = 16;
-            sock._rQi = 16;
+            sock._rQi = 15;
             sock._rQbufferSize = 20;
             const msg = { data: new Uint8Array(6).buffer };
             sock._recvMessage(msg);
-            expect(sock._rQlen).to.equal(6);
+            expect(sock._rQlen).to.equal(7);
             expect(sock._rQi).to.equal(0);
-            expect(sock._rQ.length).to.equal(48);
+            expect(sock._rQ.length).to.equal(56);
         });
     });
 });