supercollider · mossheim · Jul 12, 2020 · Jun 1, 2020
diff --git a/common/SC_ServerBootDelayWarning.cpp b/common/SC_ServerBootDelayWarning.cpp
@@ -0,0 +1,44 @@
+#include "SC_ServerBootDelayWarning.h"
+
+#ifdef _WIN32
+#    include <iostream>
+#    include <thread>
+#    include <mutex>
+#    include <chrono>
+#    include <condition_variable>
+
+static bool g_isServerBooted = false;
+static std::mutex g_serverBootWarningMutex;
+static std::condition_variable g_serverBootWarningConditionVariable;
+static std::thread g_bootWarningThread;
+
+static void displayWarningIfServerHasNotBooted() {
+    std::unique_lock<std::mutex> lock(g_serverBootWarningMutex);
+
+    if (!g_serverBootWarningConditionVariable.wait_for(lock, std::chrono::seconds(10),
+                                                       [] { return g_isServerBooted; })) {
+        std::cout << "Server: possible boot delay." << std::endl;
+        std::cout << "On some Windows-based machines, Windows Defender sometimes ";
+        std::cout << "delays server boot by one minute." << std::endl;
+        std::cout << "You can add scsynth.exe and/or supernova.exe *processes* to ";
+        std::cout << "Windows Defender exclusion list to avoid this delay. It's safe." << std::endl;
+    }
+}
+#endif //_WIN32
+
+void startServerBootDelayWarningTimer() {
+#ifdef _WIN32
+    g_bootWarningThread = std::thread(displayWarningIfServerHasNotBooted);
+#endif //_WIN32
+}
+
+void stopServerBootDelayWarningTimer() {
+#ifdef _WIN32
+    {
+        const std::lock_guard<std::mutex> lock(g_serverBootWarningMutex);
+        g_isServerBooted = true;
+    }
+    g_serverBootWarningConditionVariable.notify_all();
+    g_bootWarningThread.join();
+#endif //_WIN32
+}
diff --git a/common/SC_ServerBootDelayWarning.h b/common/SC_ServerBootDelayWarning.h
@@ -0,0 +1,14 @@
+// Add a warning when Windows Defender delays scsynth boot by 60+ seconds
+// cf. github issue #4368
+
+#pragma once
+
+// On Windows, starts a timer that will display a warning message
+// after 10 seconds if the server has not booted,
+// which may be due to Windows Defender.
+// On other platforms, it does not do anything.
+// Must be called at the start of the server boot sequence.
+void startServerBootDelayWarningTimer();
+
+// Must be called at the end of the server boot sequence.
+void stopServerBootDelayWarningTimer();
diff --git a/server/scsynth/CMakeLists.txt b/server/scsynth/CMakeLists.txt
@@ -84,6 +84,7 @@ set(scsynth_sources
 	${CMAKE_SOURCE_DIR}/common/SC_StringParser.cpp
 	${CMAKE_SOURCE_DIR}/common/Samp.cpp
 	${CMAKE_SOURCE_DIR}/common/sc_popen.cpp
+	${CMAKE_SOURCE_DIR}/common/SC_ServerBootDelayWarning.cpp
 )
 
 if(APPLE)

diff --git a/server/scsynth/scsynth_main.cpp b/server/scsynth/scsynth_main.cpp
@@ -22,6 +22,7 @@
 #include "SC_WorldOptions.h"
 #include "SC_Version.hpp"
 #include "SC_EventLoop.hpp"
+#include "SC_ServerBootDelayWarning.h"
 #include <cstring>
 #include <stdio.h>
 #include <stdarg.h>
@@ -44,7 +45,6 @@ inline int setlinebuf(FILE* stream) { return setvbuf(stream, (char*)0, _IONBF, 0
 
 #endif
 
-
 void Usage();
 void Usage() {
     WorldOptions defaultOptions;
@@ -126,6 +126,8 @@ void Usage() {
 
 
 int scsynth_main(int argc, char** argv) {
+    startServerBootDelayWarningTimer();
+
     setlinebuf(stdout);
 
     EventLoop::setup();
@@ -340,6 +342,8 @@ int scsynth_main(int argc, char** argv) {
         }
     }
 
+    stopServerBootDelayWarningTimer();
+
     if (options.mVerbosity >= 0) {
 #ifdef NDEBUG
         scprintf("SuperCollider 3 server ready.\n");

diff --git a/server/supernova/CMakeLists.txt b/server/supernova/CMakeLists.txt
@@ -51,6 +51,7 @@ set(libsupernova_src
     ${CMAKE_SOURCE_DIR}/common/Samp.cpp
     ${CMAKE_SOURCE_DIR}/common/SC_fftlib.cpp
     ${CMAKE_SOURCE_DIR}/common/SC_StringParser.cpp
+    ${CMAKE_SOURCE_DIR}/common/SC_ServerBootDelayWarning.cpp
     server/buffer_manager.cpp
     server/memory_pool.cpp
     server/node_graph.cpp

diff --git a/server/supernova/server/main.cpp b/server/supernova/server/main.cpp
@@ -22,6 +22,9 @@
 #include <string>
 #include <vector>
 
+#include "SC_Win32Utils.h"
+#include "SC_ServerBootDelayWarning.h"
+
 #include <boost/filesystem/path.hpp>
 #include <boost/algorithm/string.hpp>
 
@@ -337,6 +340,8 @@ int main(int argc, char* argv[]) {
     cout << "compiled for debugging" << endl;
 #endif
 
+    startServerBootDelayWarningTimer();
+
     // FIXME should have more granular error handling
     try {
         server_shared_memory_creator::cleanup(args.port());
@@ -346,6 +351,8 @@ int main(int argc, char* argv[]) {
         set_plugin_paths(args, sc_factory.get());
         load_synthdefs(server, args);
 
+        stopServerBootDelayWarningTimer();
+
         if (!args.non_rt) {
             try {
                 start_audio_backend(args);