From ebdcfca253b3752c10f9e90021c230f789867263 Mon Sep 17 00:00:00 2001
From: Shihui Huang <sh4480@nyu.edu>
Date: Fri, 4 Oct 2024 14:47:30 -0400
Subject: [PATCH] [UNDERTOW-2481] Add
 DEFAULT_HTTP2_SETTINGS_INITIAL_WINDOW_SIZE

---
 core/src/main/java/io/undertow/UndertowOptions.java         | 4 ++++
 .../main/java/io/undertow/protocols/http2/Http2Channel.java | 6 ++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/core/src/main/java/io/undertow/UndertowOptions.java b/core/src/main/java/io/undertow/UndertowOptions.java
index b8d0b2553c..6279a8b2a4 100644
--- a/core/src/main/java/io/undertow/UndertowOptions.java
+++ b/core/src/main/java/io/undertow/UndertowOptions.java
@@ -285,6 +285,10 @@ public class UndertowOptions {
      * Max frame size for HTTP2.
      *  <br>UNIT: Bytes.
      */
+    public static final int DEFAULT_HTTP2_SETTINGS_INITIAL_WINDOW_SIZE = 65535;
+    /**
+     * Default value of {@link #HTTP2_SETTINGS_INITIAL_WINDOW_SIZE}. <br>UNIT: Bytes.
+     */
     public static final Option<Integer> HTTP2_SETTINGS_MAX_FRAME_SIZE = Option.simple(UndertowOptions.class, "HTTP2_SETTINGS_MAX_FRAME_SIZE", Integer.class);
 
     /**
diff --git a/core/src/main/java/io/undertow/protocols/http2/Http2Channel.java b/core/src/main/java/io/undertow/protocols/http2/Http2Channel.java
index da120f0fc9..95e4045259 100644
--- a/core/src/main/java/io/undertow/protocols/http2/Http2Channel.java
+++ b/core/src/main/java/io/undertow/protocols/http2/Http2Channel.java
@@ -145,8 +145,6 @@ public class Http2Channel extends AbstractFramedChannel<Http2Channel, AbstractHt
 
     static final int CONTINUATION_FLAG_END_HEADERS = 0x4;
 
-    public static final int DEFAULT_INITIAL_WINDOW_SIZE = 65535;
-
     static final byte[] PREFACE_BYTES = {
             0x50, 0x52, 0x49, 0x20, 0x2a, 0x20, 0x48, 0x54,
             0x54, 0x50, 0x2f, 0x32, 0x2e, 0x30, 0x0d, 0x0a,
@@ -226,7 +224,7 @@ public class Http2Channel extends AbstractFramedChannel<Http2Channel, AbstractHt
     /**
      * The initial window size for newly created channels, guarded by {@link #flowControlLock}
      */
-    private volatile int initialSendWindowSize = DEFAULT_INITIAL_WINDOW_SIZE;
+    private volatile int initialSendWindowSize = UndertowOptions.DEFAULT_HTTP2_SETTINGS_INITIAL_WINDOW_SIZE;
     /**
      * How much data we can send to the remote endpoint, at the connection level, guarded by {@link #flowControlLock}
      */
@@ -253,7 +251,7 @@ public Http2Channel(StreamConnection connectedStreamChannel, String protocol, By
         streamIdCounter = clientSide ? (fromUpgrade ? 3 : 1) : 2;
 
         pushEnabled = settings.get(UndertowOptions.HTTP2_SETTINGS_ENABLE_PUSH, true);
-        this.initialReceiveWindowSize = settings.get(UndertowOptions.HTTP2_SETTINGS_INITIAL_WINDOW_SIZE, DEFAULT_INITIAL_WINDOW_SIZE);
+        this.initialReceiveWindowSize = settings.get(UndertowOptions.HTTP2_SETTINGS_INITIAL_WINDOW_SIZE, UndertowOptions.DEFAULT_HTTP2_SETTINGS_INITIAL_WINDOW_SIZE);
         this.receiveWindowSize = initialReceiveWindowSize;
         this.receiveMaxConcurrentStreams = settings.get(UndertowOptions.HTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, UndertowOptions.DEFAULT_HTTP2_SETTINGS_MAX_CONCURRENT_STREAMS);