Fix websocket in shared memory environment (#19247)

Author: ArmstrongCN

src/library_websocket.js

@@ -347,7 +347,7 @@ var LibraryWebSocket = {
 
     dbg('emscripten_websocket_send_binary(socketId='+socketId+',binaryData='+binaryData+ ',dataLength='+dataLength+'), ' + s);
 #endif
-#if PTHREADS
+#if SHARED_MEMORY
     // TODO: This is temporary to cast a shared Uint8Array to a non-shared Uint8Array. This could be removed if WebSocket API is improved
     // to allow passing in views to SharedArrayBuffers
     socket.send(new Uint8Array({{{ makeHEAPView('U8', 'binaryData', 'binaryData+dataLength') }}}));

test/test_sockets.py

@@ -325,9 +325,14 @@ def test_nodejs_sockets_echo_subprotocol(self):
 
   # Test Emscripten WebSockets API to send and receive text and binary messages against an echo server.
   # N.B. running this test requires 'npm install ws' in Emscripten root directory
-  def test_websocket_send(self):
+  # NOTE: Shared buffer is not allowed for websocket sending.
+  @parameterized({
+    '': [[]],
+    'shared': [['-sSHARED_MEMORY']],
+  })
+  def test_websocket_send(self, args):
     with NodeJsWebSocketEchoServerProcess():
-      self.btest_exit(test_file('websocket/test_websocket_send.c'), args=['-lwebsocket', '-sNO_EXIT_RUNTIME', '-sWEBSOCKET_DEBUG'])
+      self.btest_exit(test_file('websocket/test_websocket_send.c'), args=['-lwebsocket', '-sNO_EXIT_RUNTIME', '-sWEBSOCKET_DEBUG'] + args)
 
   # Test that native POSIX sockets API can be used by proxying calls to an intermediate WebSockets
   # -> POSIX sockets bridge server