From 7c4ecaf509bb851eb2750ead1dfeed66a39d9b99 Mon Sep 17 00:00:00 2001
From: Ali Mohammad Pur <ali.mpfard@gmail.com>
Date: Thu, 14 May 2026 14:39:07 +0200
Subject: [PATCH] LibRequests+RequestServer: Send oversized ws frames via
 shared memory

---
 Libraries/LibRequests/WebSocket.cpp             | 13 +++++++++++++
 Services/RequestServer/ConnectionFromClient.cpp | 13 +++++++++++++
 Services/RequestServer/ConnectionFromClient.h   |  1 +
 Services/RequestServer/RequestServer.ipc        |  1 +
 4 files changed, 28 insertions(+)

diff --git a/Libraries/LibRequests/WebSocket.cpp b/Libraries/LibRequests/WebSocket.cpp
index eb4a952aca..02bf929f0b 100644
--- a/Libraries/LibRequests/WebSocket.cpp
+++ b/Libraries/LibRequests/WebSocket.cpp
@@ -4,11 +4,14 @@
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
+#include <LibCore/AnonymousBuffer.h>
 #include <LibRequests/RequestClient.h>
 #include <LibRequests/WebSocket.h>
 
 namespace Requests {
 
+static constexpr size_t WEBSOCKET_SHARED_MEMORY_THRESHOLD = 16 * MiB;
+
 WebSocket::WebSocket(RequestClient& client, u64 websocket_id)
     : m_client(client)
     , m_websocket_id(websocket_id)
@@ -39,6 +42,16 @@ void WebSocket::send(ReadonlyBytes binary_or_text_message, bool is_text)
 {
     if (!m_client)
         return;
+    if (binary_or_text_message.size() >= WEBSOCKET_SHARED_MEMORY_THRESHOLD) {
+        auto buffer_or_error = Core::AnonymousBuffer::create_with_size(binary_or_text_message.size());
+        if (!buffer_or_error.is_error()) {
+            auto buffer = buffer_or_error.release_value();
+            __builtin_memcpy(buffer.data<void>(), binary_or_text_message.data(), binary_or_text_message.size());
+            m_client->async_websocket_send_shared(m_websocket_id, is_text, move(buffer));
+            return;
+        }
+        dbgln("WebSocket::send: failed to allocate shared buffer for {} bytes: {}", binary_or_text_message.size(), buffer_or_error.error());
+    }
     m_client->async_websocket_send(m_websocket_id, is_text, binary_or_text_message);
 }
 
diff --git a/Services/RequestServer/ConnectionFromClient.cpp b/Services/RequestServer/ConnectionFromClient.cpp
index c81ee644b1..643eebb6bb 100644
--- a/Services/RequestServer/ConnectionFromClient.cpp
+++ b/Services/RequestServer/ConnectionFromClient.cpp
@@ -586,6 +586,19 @@ void ConnectionFromClient::websocket_send(u64 websocket_id, bool is_text, ByteBu
         connection->send(WebSocket::Message { move(data), is_text });
 }
 
+void ConnectionFromClient::websocket_send_shared(u64 websocket_id, bool is_text, Core::AnonymousBuffer data)
+{
+    auto* connection = m_websockets.get(websocket_id).value_or({});
+    if (!connection || connection->ready_state() != WebSocket::ReadyState::Open)
+        return;
+    auto byte_buffer_or_error = ByteBuffer::copy(data.bytes());
+    if (byte_buffer_or_error.is_error()) {
+        dbgln("websocket_send_shared: failed to copy {} bytes from shared buffer: {}", data.size(), byte_buffer_or_error.error());
+        return;
+    }
+    connection->send(WebSocket::Message { byte_buffer_or_error.release_value(), is_text });
+}
+
 void ConnectionFromClient::websocket_close(u64 websocket_id, u16 code, ByteString reason)
 {
     if (m_pending_websockets.remove(websocket_id)) {
diff --git a/Services/RequestServer/ConnectionFromClient.h b/Services/RequestServer/ConnectionFromClient.h
index 20f2682b1b..a4f7910d58 100644
--- a/Services/RequestServer/ConnectionFromClient.h
+++ b/Services/RequestServer/ConnectionFromClient.h
@@ -72,6 +72,7 @@ private:
 
     virtual void websocket_connect(u64 websocket_id, URL::URL, ByteString, Vector<ByteString>, Vector<ByteString>, Vector<HTTP::Header>) override;
     virtual void websocket_send(u64 websocket_id, bool, ByteBuffer) override;
+    virtual void websocket_send_shared(u64 websocket_id, bool, Core::AnonymousBuffer) override;
     virtual void websocket_close(u64 websocket_id, u16, ByteString) override;
     virtual Messages::RequestServer::WebsocketSetCertificateResponse websocket_set_certificate(u64, ByteString, ByteString) override;
 
diff --git a/Services/RequestServer/RequestServer.ipc b/Services/RequestServer/RequestServer.ipc
index a127963f8a..1b465ae36a 100644
--- a/Services/RequestServer/RequestServer.ipc
+++ b/Services/RequestServer/RequestServer.ipc
@@ -42,6 +42,7 @@ endpoint RequestServer
     // Websocket Connection API
     websocket_connect(u64 websocket_id, URL::URL url, ByteString origin, Vector<ByteString> protocols, Vector<ByteString> extensions, Vector<HTTP::Header> additional_request_headers) =|
     websocket_send(u64 websocket_id, bool is_text, ByteBuffer data) =|
+    websocket_send_shared(u64 websocket_id, bool is_text, Core::AnonymousBuffer data) =|
     websocket_close(u64 websocket_id, u16 code, ByteString reason) =|
     websocket_set_certificate(u64 request_id, ByteString certificate, ByteString key) => (bool success)