chore: fatal log example (#120)

Author: bobbyg603

Content/UI/W_BugSplatDemo.uasset

@@ -70,21 +70,207 @@ To create a `.dSYM` file for a macOS build invoke `RunUAT.command` with the `-En
 
 Before attempting to use the BugSplat plugin to capture crashes on Mobile, please ensure you've completed the [iOS](https://docs.unrealengine.com/5.0/en-US/setting-up-an-unreal-engine-project-for-ios/) and [Android](https://docs.unrealengine.com/5.0/en-US/android-support-for-unreal-engine/) quickstart guides.
 
-In order to get function names and line numbers in your iOS crash reports, please make the following changes in the `iOS` section of `Project Settings`.
+To enable crash reporting, ensure the `Enable iOS Crash Reporting` and `Enable Android Crash Reporting` options are selected. Also, ensure that `Enable Automatic Symbol Uploads` is checked so that your crash reports contain function names and line numbers.
+
+#### iOS
+
+> [!NOTE]
+> The Unreal iOS project's build process includes a `Build Phase called Generate dSYM for archive, and strip`, which executes after the Unreal PostBuildSteps. However, this Build Phase must complete before the `dSYM` file (debug symbols) is generated. Due to this timing, BugSplat cannot upload the `dSYM` immediately during the initial build. Instead, BugSplat will upload the `dSYM` during the next incremental build in Xcode. Alternatively, you can follow the [example](https://github.com/BugSplat-Git/bugsplat-apple/blob/main/Symbol_Upload_Examples/Build-Phase-symbol-upload.sh) in our bugsplat-apple repo to configure a custom Build Phase for symbol uploads.
+
+To get function names and line numbers in your iOS crash reports, please make the following changes in the `iOS` section of `Project Settings`.
 
 | Option | Value |
 |--------|-------|
 | Generate dSYMs for code debugging and profiling| true |
 | Generate dSYMs as a bundle for third-party crash tools | true |
 | Support bitcode in shipping | false |
 
-To enable crash reporting, ensure the `Enable iOS Crash Reporting` and `Enable Android Crash Reporting` options are selected. Also ensure that `Enable Automatic Symbol Uploads` is checked so that your crash reports contain function names and line numbers.
-
 Note that sometimes iOS applications won't crash while the USB cable is connected. If this happens, disconnect the USB cable and re-run the application to trigger a crash.
 
-> [!NOTE]
-> The Unreal iOS project's build process includes a `Build Phase called Generate dSYM for archive, and strip`, which executes after the Unreal PostBuildSteps. However, this Build Phase must complete before the `dSYM` file (debug symbols) is generated. Due to this timing, BugSplat cannot upload the `dSYM` immediately during the initial build. Instead, BugSplat will upload the `dSYM` during the next incremental build in Xcode. Alternatively, you can follow the [example](https://github.com/BugSplat-Git/bugsplat-apple/blob/main/Symbol_Upload_Examples/Build-Phase-symbol-upload.sh) in our bugsplat-apple repo to configure your a custom Build Phase for symbol uploads.
+#### Android
+
+> ![Note]
+> Code is aggressively optimized when building for Android. Oftentimes, Unreal's build process optimizes away code that generates simple errors used in testing. To test a null pointer dereference, you can add the `volatile` keyword to work around compiler optimizations.
+
+
+Fatal Errors on Android raise a `SIGTRAP` and require extra configuration so that they can be reported to BugSplat.
+
+[MyUnrealCrasherErrorOutputDevice.h](https://github.com/BugSplat-Git/my-unreal-crasher/blob/b0a805505a661d6729657bcae724e64dea31484b/Source/MyUnrealCrasher/MyUnrealCrasherAndroidErrorOutputDevice.h)
+```cpp
+#pragma once
+
+#include "CoreMinimal.h"
+#include "Misc/OutputDeviceError.h"
+
+#if PLATFORM_ANDROID
+class FMyUnrealCrasherAndroidErrorOutputDevice : public FOutputDeviceError
+{
+public:
+	virtual ~FMyUnrealCrasherAndroidErrorOutputDevice() {}
+	
+	virtual void Serialize(const TCHAR* V, ELogVerbosity::Type Verbosity, const FName& Category) override;
+	virtual void HandleError() override;
+	
+	static FOutputDeviceError* GetErrorOutputDevice();
+	
+private:
+	void RequestExit(bool Force, const TCHAR* CallSite);
+};
+#endif
+```
+
+[MyUnrealCrasherErrorOutputDevice.cpp](https://github.com/BugSplat-Git/my-unreal-crasher/blob/b0a805505a661d6729657bcae724e64dea31484b/Source/MyUnrealCrasher/MyUnrealCrasherAndroidErrorOutputDevice.cpp)
+```cpp
+// Copyright © BugSplat. All rights reserved.
+#include "MyUnrealCrasherAndroidErrorOutputDevice.h"
+
+#include "CoreMinimal.h"
+#include "CoreGlobals.h"
+#include "Misc/OutputDevice.h"
+#include "Misc/OutputDeviceHelper.h"
+#include "Misc/App.h"
+#include "Misc/CoreDelegates.h"
+#include "Misc/FeedbackContext.h"
+#include "HAL/PlatformMisc.h"
+#include "HAL/PlatformCrt.h"
+
+#if PLATFORM_ANDROID
+#include "Android/AndroidPlatform.h" // For LogAndroid
+
+FOutputDeviceError* FMyUnrealCrasherAndroidErrorOutputDevice::GetErrorOutputDevice()
+{
+	static FMyUnrealCrasherAndroidErrorOutputDevice ErrorOutputDevice;
+	return &ErrorOutputDevice;
+}
+
+void FMyUnrealCrasherAndroidErrorOutputDevice::Serialize( const TCHAR* Msg, ELogVerbosity::Type Verbosity, const class FName& Category )
+{
+	FPlatformMisc::LowLevelOutputDebugString(*FOutputDeviceHelper::FormatLogLine(Verbosity, Category, Msg, GPrintLogTimes));
+
+	static int32 CallCount = 0;
+	int32 NewCallCount = FPlatformAtomics::InterlockedIncrement(&CallCount);
+	if(GIsCriticalError == 0 && NewCallCount == 1)
+	{
+		// First appError.
+		GIsCriticalError = 1;
+
+		FCString::Strncpy(GErrorExceptionDescription, Msg, UE_ARRAY_COUNT(GErrorExceptionDescription));
+	}
+	else
+	{
+		UE_LOG(LogAndroid, Error, TEXT("Error reentered: %s"), Msg);
+	}
+
+	if (GIsGuarded)
+	{
+		UE_DEBUG_BREAK();
+	}
+	else
+	{
+		HandleError();
+		RequestExit(true, TEXT("MyUnrealCrasherAndroidErrorOutputDevice::Serialize.!GIsGuarded"));
+	}
+}
+
+void FMyUnrealCrasherAndroidErrorOutputDevice::HandleError()
+{
+	static int32 CallCount = 0;
+	int32 NewCallCount = FPlatformAtomics::InterlockedIncrement(&CallCount);
+
+	if (NewCallCount != 1)
+	{
+		UE_LOG(LogAndroid, Error, TEXT("HandleError re-entered."));
+		return;
+	}
+	
+	GIsGuarded = 0;
+	GIsRunning = 0;
+	GIsCriticalError = 1;
+	GLogConsole = NULL;
+	GErrorHist[UE_ARRAY_COUNT(GErrorHist) - 1] = 0;
+
+	// Dump the error and flush the log.
+#if !NO_LOGGING
+	FDebug::LogFormattedMessageWithCallstack(LogAndroid.GetCategoryName(), __FILE__, __LINE__, TEXT("=== Critical error: ==="), GErrorHist, ELogVerbosity::Error);
+#endif
+	
+	GLog->Panic();
+
+	FCoreDelegates::OnHandleSystemError.Broadcast();
+	FCoreDelegates::OnShutdownAfterError.Broadcast();
+}
+
+
+void FMyUnrealCrasherAndroidErrorOutputDevice::RequestExit( bool Force, const TCHAR* CallSite)
+{
+
+#if PLATFORM_COMPILER_OPTIMIZATION_PG_PROFILING
+	// Write the PGO profiling file on a clean shutdown.
+	extern void PGO_WriteFile();
+	if (!GIsCriticalError)
+	{
+		PGO_WriteFile();
+		// exit now to avoid a possible second PGO write when AndroidMain exits.
+		Force = true;
+	}
+#endif
+
+	UE_LOG(LogAndroid, Log, TEXT("FMyUnrealCrasherAndroidErrorOutputDevice::RequestExit(%i, %s)"), Force,
+		CallSite ? CallSite : TEXT("<NoCallSiteInfo>"));
+	if (GLog)
+	{
+		GLog->Flush();
+	}
+
+	if (Force)
+	{
+		abort(); // Abort to trigger a crash report
+	}
+	else
+	{
+		RequestEngineExit(TEXT("Android RequestExitWithCrashReporting")); // Called regardless in our version to set up the crash context
+	}
+}
+#endif
+```
+[MyUnrealCrasherGameInstance.h](https://github.com/BugSplat-Git/my-unreal-crasher/blob/b0a805505a661d6729657bcae724e64dea31484b/Source/MyUnrealCrasher/MyUnrealCrasherGameInstance.h)
+```cpp
+#pragma once
+
+#include "CoreMinimal.h"
+#include "Engine/GameInstance.h"
+#include "MyUnrealCrasherGameInstance.generated.h"
 
+UCLASS()
+class MYUNREALCRASHER_API UMyUnrealCrasherGameInstance : public UGameInstance
+{
+	GENERATED_BODY()
+
+public:
+	virtual void Init() override;
+};
+```
+
+[MyUnrealCrasherGameInstance.cpp](https://github.com/BugSplat-Git/my-unreal-crasher/blob/b0a805505a661d6729657bcae724e64dea31484b/Source/MyUnrealCrasher/MyUnrealCrasherGameInstance.cpp)
+```cpp
+//  Copyright © BugSplat. All rights reserved.
+#include "MyUnrealCrasherGameInstance.h"
+#include "MyUnrealCrasherAndroidErrorOutputDevice.h"
+
+#if PLATFORM_ANDROID
+#include <android/log.h>
+#endif
+
+void UMyUnrealCrasherGameInstance::Init()
+{
+	Super::Init();
+	UE_LOG(LogTemp, Log, TEXT("MyUnrealCrasherGameInstance::Init - Setting custom error output device"));
+
+#if PLATFORM_ANDROID
+	GError = FMyUnrealCrasherAndroidErrorOutputDevice::GetErrorOutputDevice();
+#endif
+}
+```
 
 ### Xbox and PlayStation
 

README.md

@@ -1,5 +1,4 @@
 // Copyright BugSplat. All Rights Reserved.
-
 #include "BugSplatUtils.h"
 
 void UBugSplatUtils::GenerateCrash()
@@ -21,4 +20,9 @@ void UBugSplatUtils::GenerateEnsure()
 	UE_LOG(LogTemp, Log, TEXT("BugSplat: GenerateEnsure"));
 	char* ptr = nullptr;
 	ensure(ptr != nullptr);
+}
+
+void UBugSplatUtils::GenerateFatalLog()
+{
+	UE_LOG(LogTemp, Fatal, TEXT("BugSplat: GenerateFatalLog"));
 }

Source/BugSplatRuntime/Private/BugSplatUtils.cpp

@@ -20,4 +20,7 @@ class BUGSPLATRUNTIME_API UBugSplatUtils : public UBlueprintFunctionLibrary
 
 	UFUNCTION(BlueprintCallable, Category = "BugSplat")
 	static void GenerateEnsure();
+
+	UFUNCTION(BlueprintCallable, Category = "BugSplat")
+	static void GenerateFatalLog();
 };