- moved all exception handling out of the backends

The main catch is now in D_DoomMain, only calling platform specific functions to handle the output for the error.

As a nice side effect, -norun can now be done without an exception, just by exiting D_DoomMain with a special exit code.

src/console/c_console.cpp

@@ -917,7 +917,7 @@ int PrintString (int iprintlevel, const char *outline)
 	return 0;	// Don't waste time on calculating this if nothing at all was printed...
 }
 
-extern bool gameisdead;
+bool gameisdead;
 
 int VPrintf (int printlevel, const char *format, va_list parms)
 {

src/d_main.cpp

@@ -2326,6 +2326,11 @@ void I_FatalError(const char *error, ...)
 	std::terminate(); // recursive I_FatalErrors must immediately terminate.
 }
 
+static void NewFailure ()
+{
+    I_FatalError ("Failed to allocate memory from system heap");
+}
+
 //==========================================================================
 //
 // I_Quit
@@ -2348,7 +2353,7 @@ void I_Quit()
 //
 //==========================================================================
 
-void D_DoomMain (void)
+static void D_DoomMain_Internal (void)
 {
 	int p;
 	const char *v;
@@ -2357,6 +2362,8 @@ void D_DoomMain (void)
 	FString *args;
 	int argcount;	
 	FIWadManager *iwad_man;
+	
+	std::set_new_handler(NewFailure);
 	const char *batchout = Args->CheckValue("-errorlog");
 	
 	C_InitConsole(80*8, 25*8, false);
@@ -2739,7 +2746,7 @@ void D_DoomMain (void)
 
 			if (Args->CheckParm("-norun") || batchrun)
 			{
-				throw CNoRunExit();
+				return;
 			}
 
 			V_Init2();
@@ -2830,6 +2837,25 @@ void D_DoomMain (void)
 	while (1);
 }
 
+int D_DoomMain()
+{
+	int ret = 0;
+	try
+	{
+		D_DoomMain_Internal();
+		ret = 1337;
+	}
+	catch (std::exception &error)
+	{
+		I_ShowFatalError(error.what());
+		ret = -1;
+	}
+	// Unless something really bad happened, the game should only exit through this single point in the code.
+	// No more 'exit', please.
+	// Todo: Move all engine cleanup here instead of using exit handlers and replace the scattered 'exit' calls with a special exception.
+	return ret;
+}
+
 //==========================================================================
 //
 // clean up the resources

src/d_main.h

@@ -45,7 +45,7 @@ struct CRestartException
 	char dummy;
 };
 
-void D_DoomMain (void);
+int D_DoomMain (void);
 
 
 void D_Display ();

src/posix/cocoa/i_main.mm

@@ -141,11 +141,7 @@ void I_DetectOS()
 FArgs* Args; // command line arguments
 
 
-// Newer versions of GCC than 4.2 have a bug with C++ exceptions in Objective-C++ code.
-// To work around we'll implement the try and catch in standard C++.
-// https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61759
-void OriginalMainExcept(int argc, char** argv);
-void OriginalMainTry(int argc, char** argv)
+int OriginalMainTry(int argc, char** argv)
 {
 	Args = new FArgs(argc, argv);
 
@@ -155,7 +151,7 @@ void OriginalMainTry(int argc, char** argv)
 	progdir = [[exePath stringByDeletingLastPathComponent] UTF8String];
 	progdir += "/";
 
-	D_DoomMain();
+	return D_DoomMain();
 }
 
 namespace
@@ -163,19 +159,12 @@ namespace
 
 TArray<FString> s_argv;
 
-
-void NewFailure()
-{
-	I_FatalError("Failed to allocate memory from system heap");
-}
-
 int OriginalMain(int argc, char** argv)
 {
 	printf(GAMENAME" %s - %s - Cocoa version\nCompiled on %s\n\n",
 		GetVersionString(), GetGitTime(), __DATE__);
 
 	seteuid(getuid());
-	std::set_new_handler(NewFailure);
 
 	// Set LC_NUMERIC environment variable in case some library decides to
 	// clear the setlocale call at least this will be correct.
@@ -190,9 +179,7 @@ int OriginalMain(int argc, char** argv)
 	vid_defheight = static_cast<int>(screenSize.height);
 	vid_vsync     = true;
 
-	OriginalMainExcept(argc, argv);
-
-	return 0;
+	return OriginalMainTry(argc, argv);
 }
 
 } // unnamed namespace

src/posix/cocoa/i_main_except.cpp

@@ -39,41 +39,10 @@
 #include "atterm.h"
 
 // Import some functions from i_main.mm
-void Mac_I_FatalError(const char* const message);
+
 void OriginalMainTry(int argc, char** argv);
 
 void OriginalMainExcept(int argc, char** argv)
-{
-	try
 {
 	OriginalMainTry(argc, argv);
 }
-	catch(const std::exception& error)
-	{
-		const char* const message = error.what();
-
-		if (strcmp(message, "NoRunExit"))
-		{
-			if (CVMAbortException::stacktrace.IsNotEmpty())
-			{
-				Printf("%s", CVMAbortException::stacktrace.GetChars());
-			}
-
-			if (batchrun)
-			{
-				Printf("%s\n", message);
-			}
-			else
-			{
-				Mac_I_FatalError(message);
-			}
-		}
-
-		exit(-1);
-	}
-	catch(...)
-	{
-		call_terms();
-		throw;
-	}
-}

src/posix/cocoa/i_system.mm

@@ -147,6 +147,14 @@ void I_PrintStr(const char* const message)
 }
 
 
+void Mac_I_FatalError(const char* const message);
+
+void I_ShowFatalError(const char *message)
+{
+	Mac_I_FatalError(message);
+}
+
+
 int I_PickIWad(WadStuff* const wads, const int numwads, const bool showwin, const int defaultiwad)
 {
 	if (!showwin)

src/posix/sdl/i_main.cpp

@@ -94,10 +94,6 @@ FArgs *Args;
 // CODE --------------------------------------------------------------------
 
 
-static void NewFailure ()
-{
-    I_FatalError ("Failed to allocate memory from system heap");
-}
 
 static int DoomSpecificInfo (char *buffer, char *end)
 {
@@ -170,8 +166,6 @@ int main (int argc, char **argv)
 		GetVersionString(), GetGitTime(), __DATE__);
 
 	seteuid (getuid ());
-    std::set_new_handler (NewFailure);
-
 	// Set LC_NUMERIC environment variable in case some library decides to
 	// clear the setlocale call at least this will be correct.
 	// Note that the LANG environment variable is overridden by LC_*
@@ -205,6 +199,5 @@ int main (int argc, char **argv)
 	}
 	
 	I_StartupJoysticks();
-	D_DoomMain ();
-    return 0;
+	return D_DoomMain ();
 }

src/posix/sdl/i_system.cpp

@@ -103,7 +103,6 @@ void I_Init (void)
 // I_Error
 //
 extern FILE *Logfile;
-bool gameisdead;
 
 #ifdef __APPLE__
 void Mac_I_FatalError(const char* errortext);

src/utility/doomerrors.h

@@ -82,13 +82,6 @@ protected:
 	char m_Message[MAX_ERRORTEXT];
 };
 
-class CNoRunExit : public std::runtime_error
-{
-public:
-	CNoRunExit() : std::runtime_error("NoRunExit")
-	{
-	}
-};
 
 class CRecoverableError : public CDoomError
 {

src/win32/i_main.cpp

@@ -145,15 +145,6 @@ static HMODULE hwtsapi32;		// handle to wtsapi32.dll
 
 // CODE --------------------------------------------------------------------
 
-
-#ifdef _MSC_VER
-static int NewFailure (size_t size)
-{
-	I_FatalError ("Failed to allocate %d bytes from process heap", size);
-	return 0;
-}
-#endif
-
 //==========================================================================
 //
 // UnCOM
@@ -766,12 +757,6 @@ void DoMain (HINSTANCE hInstance)
 	TIMECAPS tc;
 	DEVMODE displaysettings;
 	
-	try
-	{
-#ifdef _MSC_VER
-		_set_new_handler (NewFailure);
-#endif
-
 	// Do not use the multibyte __argv here because we want UTF-8 arguments
 	// and those can only be done by converting the Unicode variants.
 	Args = new FArgs();
@@ -868,8 +853,10 @@ void DoMain (HINSTANCE hInstance)
 	WCHAR progbuff[1024];
 	if (GetModuleFileNameW(nullptr, progbuff, sizeof progbuff) == 0)
 	{
-			I_FatalError("Could not determine program location.");
+		MessageBoc(nullptr, "Fatal", "Could not determine program location.", MB_ICONEXCLAMATION|MB_OK);
+		exit(-1);
 	}
+	
 	progbuff[1023] = '\0';
 	if (auto lastsep = wcsrchr(progbuff, '\\'))
 	{
@@ -912,7 +899,10 @@ void DoMain (HINSTANCE hInstance)
 	
 	/* register this new class with Windows */
 	if (!RegisterClass((LPWNDCLASS)&WndClass))
-			I_FatalError ("Could not register window class");
+	{
+		MessageBoxA(nullptr, "Could not register window class", "Fatal", MB_ICONEXCLAMATION|MB_OK);
+		exit(-1);
+	}
 	
 	/* create window */
 	FStringf caption("" GAMESIG " %s " X64 " (%s)", GetVersionString(), GetGitTime());
@@ -969,10 +959,10 @@ void DoMain (HINSTANCE hInstance)
 	CoInitialize (NULL);
 	atexit (UnCOM);
 	
-		D_DoomMain ();
-	}
-	catch (class CNoRunExit &)
+	int ret = D_DoomMain ();
+	if (ret == 1337) // special exit code for 'norun'.
 	{
+		// The only way D_DoomMain can exit regularly is by executing a -norun startup, which was previously handled via exception.
 		I_ShutdownGraphics();
 		if (!batchrun)
 		{
@@ -992,17 +982,18 @@ void DoMain (HINSTANCE hInstance)
 				ShowErrorPane(NULL);
 			}
 		}
-		exit(0);
 	}
-	catch (std::exception &error)
+	return ret;
+}
+
+void I_ShowFatalError(const char *msg)
 {
 	I_ShutdownGraphics ();
 	RestoreConView ();
 	S_StopMusic(true);
 	I_FlushBufferedConsoleStuff();
 	auto msg = error.what();
-		if (strcmp(msg, "NoRunExit"))
-		{
+
 	if (CVMAbortException::stacktrace.IsNotEmpty())
 	{
 		Printf("%s", CVMAbortException::stacktrace.GetChars());
@@ -1017,9 +1008,6 @@ void DoMain (HINSTANCE hInstance)
 		Printf("%s\n", msg);
 	}
 }
-		exit(-1);
-	}
-}
 
 //==========================================================================
 //

src/win32/i_system.cpp

@@ -137,7 +137,6 @@ double PerfToSec, PerfToMillisec;
 
 UINT TimerPeriod;
 
-bool gameisdead;
 int sys_ostype = 0;
 
 // PRIVATE DATA DEFINITIONS ------------------------------------------------