Restore Linux SendBackAck behaviour

electron · Apr 15, 2022 · 0abc7f0 · 0abc7f0
1 parent 5ce03c2
commit 0abc7f0
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Showing 2 changed files with 28 additions and 9 deletions.
diff --git a/shell/browser/api/electron_api_app.cc b/shell/browser/api/electron_api_app.cc
@@ -1074,8 +1074,25 @@ void App::OnFirstInstanceAck(
   Emit("first-instance-ack", data_to_send);
 }
 
-// This function handles the user calling
-// the callback parameter sent out by the second-instance event.
+// This function helps the first instance send an acknowledgement
+// back to the second instance.
+void App::SendBackAck(const ProcessSingleton::SendAckCallback& ack_callback,
+                      std::vector<const uint8_t>* ack_data) {
+#if BUILDFLAG(IS_WIN)
+  // For Windows, we use a timer to call the callback async,
+  // because we must exit ProcessSingleton::ProcessLaunchNotification
+  // before sending back the acknowledgement, otherwise
+  // the program will hang on the ConnectNamedPipe call.
+  ack_timer_.Start(FROM_HERE, base::Seconds(0),
+                   base::BindOnce(ack_callback, ack_data));
+#else
+  ack_callback.Run(ack_data);
+#endif
+}
+
+// This function is called within the first instance
+// when it prepares to send back the acknowledgement
+// to the second instance.
 void App::AckCallbackWrapper(
     const ProcessSingleton::SendAckCallback& ack_callback,
     gin::Arguments* args) {
@@ -1088,14 +1105,14 @@ void App::AckCallbackWrapper(
   if (!ack_message.encoded_message.empty()) {
     ack_to_send_ = std::vector<const uint8_t>(
         ack_message.encoded_message.begin(), ack_message.encoded_message.end());
-    ack_timer_.Start(FROM_HERE, base::Seconds(0),
-                     base::BindOnce(ack_callback, &ack_to_send_));
+    SendBackAck(ack_callback, &ack_to_send_);
   } else {
-    ack_timer_.Start(FROM_HERE, base::Seconds(0),
-                     base::BindOnce(ack_callback, nullptr));
+    SendBackAck(ack_callback, nullptr);
   }
 }
 
+// This function is called within the first instance
+// when it learns of a second instance.
 void App::OnSecondInstance(
     const base::CommandLine& cmd,
     const base::FilePath& cwd,
@@ -1111,12 +1128,12 @@ void App::OnSecondInstance(
   bool prevent_default =
       Emit("second-instance", cmd.argv(), cwd, data_value, cb);
   if (!prevent_default && send_ack_) {
-    // Call the callback ourselves, and send back nothing.
-    ack_timer_.Start(FROM_HERE, base::Seconds(0),
-                     base::BindOnce(ack_callback, nullptr));
+    SendBackAck(ack_callback, nullptr);
   }
 }
 
+// This wrapper function manages when to run
+// App::OnSecondInstance above.
 bool App::NotificationCallbackWrapper(
     const base::RepeatingCallback<
         void(const base::CommandLine& command_line,

diff --git a/shell/browser/api/electron_api_app.h b/shell/browser/api/electron_api_app.h
@@ -194,6 +194,8 @@ class App : public ElectronBrowserClient::Delegate,
   std::string GetLocale();
   std::string GetLocaleCountryCode();
   void OnFirstInstanceAck(const base::span<const uint8_t>* first_instance_data);
+  void SendBackAck(const ProcessSingleton::SendAckCallback& ack_callback,
+                   std::vector<const uint8_t>* ack_data);
   void AckCallbackWrapper(const ProcessSingleton::SendAckCallback& ack_callback,
                           gin::Arguments* args);
   void OnSecondInstance(const base::CommandLine& cmd,