Merge branch 'brainfreeze' into 'master'

Attempt to catch freezes on Windows

See merge request OpenMW/openmw!1493

4 files changed, 150 insertions, 6 deletions

diff --git a/components/crashcatcher/windows_crashcatcher.cpp b/components/crashcatcher/windows_crashcatcher.cpp
index 39ac86d7b8..e9eb60e845 100644
--- a/components/crashcatcher/windows_crashcatcher.cpp
+++ b/components/crashcatcher/windows_crashcatcher.cpp
@@ -1,10 +1,11 @@
+#include "windows_crashcatcher.hpp"
+
 #include <cassert>
 #include <cwchar>
 #include <iostream>
 #include <sstream>
 #include <thread>
 
-#include "windows_crashcatcher.hpp"
 #include "windows_crashmonitor.hpp"
 #include "windows_crashshm.hpp"
 #include <SDL_messagebox.h>
@@ -144,6 +145,7 @@ namespace Crash
         mShm->mEvent = CrashSHM::Event::Startup;
         mShm->mStartup.mShmMutex = duplicateHandle(mShmMutex);
         mShm->mStartup.mAppProcessHandle = duplicateHandle(GetCurrentProcess());
+        mShm->mStartup.mAppMainThreadId = GetThreadId(GetCurrentThread());
         mShm->mStartup.mSignalApp = duplicateHandle(mSignalAppEvent);
         mShm->mStartup.mSignalMonitor = duplicateHandle(mSignalMonitorEvent);
 
@@ -196,7 +198,7 @@ namespace Crash
         // must remain until monitor has finished
         waitMonitor();
 
-        std::string message = "OpenMW has encountered a fatal error.\nCrash log saved to '" + std::string(mShm->mStartup.mLogFilePath) + "'.\n Please report this to https://gitlab.com/OpenMW/openmw/issues !";
+        std::string message = "OpenMW has encountered a fatal error.\nCrash log saved to '" + std::string(mShm->mStartup.mLogFilePath) + "'.\nPlease report this to https://gitlab.com/OpenMW/openmw/issues !";
         SDL_ShowSimpleMessageBox(0, "Fatal Error", message.c_str(), nullptr);
     }
 
diff --git a/components/crashcatcher/windows_crashmonitor.cpp b/components/crashcatcher/windows_crashmonitor.cpp
index 8976deb2ea..50d3fc08a1 100644
--- a/components/crashcatcher/windows_crashmonitor.cpp
+++ b/components/crashcatcher/windows_crashmonitor.cpp
@@ -1,3 +1,5 @@
+#include "windows_crashmonitor.hpp"
+
 #undef WIN32_LEAN_AND_MEAN
 #define WIN32_LEAN_AND_MEAN
 #include <Windows.h>
@@ -9,13 +11,15 @@
 #include <memory>
 #include <sstream>
 
+#include <SDL_messagebox.h>
+
 #include "windows_crashcatcher.hpp"
-#include "windows_crashmonitor.hpp"
 #include "windows_crashshm.hpp"
 #include <components/debug/debuglog.hpp>
 
 namespace Crash
 {
+    std::unordered_map<HWINEVENTHOOK, CrashMonitor*> CrashMonitor::smEventHookOwners{};
 
     CrashMonitor::CrashMonitor(HANDLE shmHandle)
         : mShmHandle(shmHandle)
@@ -28,6 +32,7 @@ namespace Crash
 
         mShmMutex = mShm->mStartup.mShmMutex;
         mAppProcessHandle = mShm->mStartup.mAppProcessHandle;
+        mAppMainThreadId = mShm->mStartup.mAppMainThreadId;
         mSignalAppEvent = mShm->mStartup.mSignalApp;
         mSignalMonitorEvent = mShm->mStartup.mSignalMonitor;
     }
@@ -80,6 +85,61 @@ namespace Crash
         return code == STILL_ACTIVE;
     }
 
+    bool CrashMonitor::isAppFrozen()
+    {
+        MSG message;
+        // Allow the event hook callback to run
+        PeekMessage(&message, nullptr, 0, 0, PM_NOREMOVE);
+
+        if (!mAppWindowHandle)
+        {
+            EnumWindows([](HWND handle, LPARAM param) -> BOOL {
+                CrashMonitor& crashMonitor = *(CrashMonitor*)param;
+                DWORD processId;
+                if (GetWindowThreadProcessId(handle, &processId) == crashMonitor.mAppMainThreadId && processId == GetProcessId(crashMonitor.mAppProcessHandle))
+                {
+                    if (GetWindow(handle, GW_OWNER) == 0)
+                    {
+                        crashMonitor.mAppWindowHandle = handle;
+                        return false;
+                    }
+                }
+                return true;
+                }, (LPARAM)this);
+            if (mAppWindowHandle)
+            {
+                DWORD processId;
+                GetWindowThreadProcessId(mAppWindowHandle, &processId);
+                HWINEVENTHOOK eventHookHandle = SetWinEventHook(EVENT_OBJECT_DESTROY, EVENT_OBJECT_DESTROY, nullptr,
+                    [](HWINEVENTHOOK hWinEventHook, DWORD event, HWND windowHandle, LONG objectId, LONG childId, DWORD eventThread, DWORD eventTime)
+                    {
+                        CrashMonitor& crashMonitor = *smEventHookOwners[hWinEventHook];
+                        if (event == EVENT_OBJECT_DESTROY && windowHandle == crashMonitor.mAppWindowHandle && objectId == OBJID_WINDOW && childId == INDEXID_CONTAINER)
+                        {
+                            crashMonitor.mAppWindowHandle = nullptr;
+                            smEventHookOwners.erase(hWinEventHook);
+                            UnhookWinEvent(hWinEventHook);
+                        }
+                    }, processId, mAppMainThreadId, WINEVENT_OUTOFCONTEXT);
+                smEventHookOwners[eventHookHandle] = this;
+            }
+            else
+                return false;
+        }
+        if (IsHungAppWindow)
+            return IsHungAppWindow(mAppWindowHandle);
+        else
+        {
+            BOOL debuggerPresent;
+
+            if (CheckRemoteDebuggerPresent(mAppProcessHandle, &debuggerPresent) && debuggerPresent)
+                return false;
+            if (SendMessageTimeoutA(mAppWindowHandle, WM_NULL, 0, 0, 0, 5000, nullptr) == 0)
+                return GetLastError() == ERROR_TIMEOUT;
+        }
+        return false;
+    }
+
     void CrashMonitor::run()
     {
         try
@@ -88,9 +148,24 @@ namespace Crash
             signalApp();
 
             bool running = true;
-            while (isAppAlive() && running)
+            bool frozen = false;
+            while (isAppAlive() && running && !mFreezeAbort)
             {
-                if (waitApp())
+                if (isAppFrozen())
+                {
+                    if (!frozen)
+                    {
+                        showFreezeMessageBox();
+                        frozen = true;
+                    }
+                }
+                else if (frozen)
+                {
+                    hideFreezeMessageBox();
+                    frozen = false;
+                }
+
+                if (!mFreezeAbort && waitApp())
                 {
                     shmLock();
 
@@ -113,6 +188,16 @@ namespace Crash
                 }
             }
 
+            if (frozen)
+                hideFreezeMessageBox();
+
+            if (mFreezeAbort)
+            {
+                TerminateProcess(mAppProcessHandle, 0xDEAD);
+                std::string message = "OpenMW appears to have frozen.\nCrash log saved to '" + std::string(mShm->mStartup.mLogFilePath) + "'.\nPlease report this to https://gitlab.com/OpenMW/openmw/issues !";
+                SDL_ShowSimpleMessageBox(0, "Fatal Error", message.c_str(), nullptr);
+            }
+
         } 
         catch (...)
         {
@@ -185,4 +270,43 @@ namespace Crash
         }
     }
 
+    void CrashMonitor::showFreezeMessageBox()
+    {
+        std::thread messageBoxThread([&]() {
+            SDL_MessageBoxButtonData button = { SDL_MESSAGEBOX_BUTTON_RETURNKEY_DEFAULT, 0, "Abort" };
+            SDL_MessageBoxData messageBoxData = {
+                SDL_MESSAGEBOX_ERROR,
+                nullptr,
+                "OpenMW appears to have frozen",
+                "OpenMW appears to have frozen. Press Abort to terminate it and generate a crash dump.\nIf OpenMW hasn't actually frozen, this message box will disappear a within a few seconds of it becoming responsive.",
+                1,
+                &button,
+                nullptr
+            };
+
+            int buttonId;
+            if (SDL_ShowMessageBox(&messageBoxData, &buttonId) == 0 && buttonId == 0)
+                mFreezeAbort = true;
+            });
+
+        mFreezeMessageBoxThreadId = GetThreadId(messageBoxThread.native_handle());
+        messageBoxThread.detach();
+    }
+
+    void CrashMonitor::hideFreezeMessageBox()
+    {
+        if (!mFreezeMessageBoxThreadId)
+            return;
+
+        EnumWindows([](HWND handle, LPARAM param) -> BOOL {
+            CrashMonitor& crashMonitor = *(CrashMonitor*)param;
+            DWORD processId;
+            if (GetWindowThreadProcessId(handle, &processId) == crashMonitor.mFreezeMessageBoxThreadId && processId == GetCurrentProcessId())
+                PostMessage(handle, WM_CLOSE, 0, 0);
+            return true;
+            }, (LPARAM)this);
+
+        mFreezeMessageBoxThreadId = 0;
+    }
+
 } // namespace Crash
diff --git a/components/crashcatcher/windows_crashmonitor.hpp b/components/crashcatcher/windows_crashmonitor.hpp
index 678d38435c..4028362836 100644
--- a/components/crashcatcher/windows_crashmonitor.hpp
+++ b/components/crashcatcher/windows_crashmonitor.hpp
@@ -1,7 +1,11 @@
 #ifndef WINDOWS_CRASHMONITOR_HPP
 #define WINDOWS_CRASHMONITOR_HPP
 
-#include <windef.h>
+#undef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN
+#include <Windows.h>
+
+#include <atomic>
 
 namespace Crash
 {
@@ -21,6 +25,8 @@ public:
 private:
 
     HANDLE mAppProcessHandle = nullptr;
+    DWORD mAppMainThreadId = 0;
+    HWND mAppWindowHandle = nullptr;
 
     // triggered when the monitor process wants to wake the parent process (received via SHM)
     HANDLE mSignalAppEvent = nullptr;
@@ -31,17 +37,28 @@ private:
     HANDLE mShmHandle = nullptr;
     HANDLE mShmMutex = nullptr;
 
+    DWORD mFreezeMessageBoxThreadId = 0;
+    std::atomic_bool mFreezeAbort;
+
+    static std::unordered_map<HWINEVENTHOOK, CrashMonitor*> smEventHookOwners;
+
     void signalApp() const;
 
     bool waitApp() const;
 
     bool isAppAlive() const;
 
+    bool isAppFrozen();
+
     void shmLock();
 
     void shmUnlock();
 
     void handleCrash();
+
+    void showFreezeMessageBox();
+
+    void hideFreezeMessageBox();
 };
 
 } // namespace Crash
diff --git a/components/crashcatcher/windows_crashshm.hpp b/components/crashcatcher/windows_crashshm.hpp
index 47929a45fe..a474600f94 100644
--- a/components/crashcatcher/windows_crashshm.hpp
+++ b/components/crashcatcher/windows_crashshm.hpp
@@ -26,6 +26,7 @@ namespace Crash
         struct Startup
         {
             HANDLE mAppProcessHandle;
+            DWORD mAppMainThreadId;
             HANDLE mSignalApp;
             HANDLE mSignalMonitor;
             HANDLE mShmMutex;