Output a log, savegame and screenshot on desync events

src/os/macosx/crashlog_osx.cpp

@@ -375,6 +375,8 @@ class CrashLogOSX : public CrashLog {
 	}
 
 public:
+	struct DesyncTag {};
+
 	/**
 	 * A crash log is always generated by signal.
 	 * @param signum the signal that was caused by the crash.
@@ -399,6 +401,13 @@ public:
 #endif /* WITH_UCONTEXT */
 	}
 
+	CrashLogOSX(DesyncTag tag) : signum(0), si(nullptr), context(nullptr), signal_instruction_ptr_valid(false)
+	{
+		filename_log[0] = '\0';
+		filename_save[0] = '\0';
+		filename_screenshot[0] = '\0';
+	}
+
 	/** Generate the crash log. */
 	bool MakeCrashLog()
 	{
@@ -502,3 +511,9 @@ void CDECL HandleCrash(int signum, siginfo_t *si, void *context)
 		sigaction(*i, &sa, nullptr);
 	}
 }
+
+/* static */ void CrashLog::DesyncCrashLog()
+{
+	CrashLogOSX log(CrashLogOSX::DesyncTag{});
+	log.MakeDesyncCrashLog();
+}