shared: move ScopeExit from riscv64 arch kernel code

this file is c++11 only.

Change-Id: Ibff7acec00337a9f56f9b8e29ea262c8d64c2446
Reviewed-on: https://review.haiku-os.org/c/haiku/+/5292
Tested-by: Commit checker robot <[email protected]>
Reviewed-by: Fredrik Holmqvist <[email protected]>
Reviewed-by: Jérôme Duval <[email protected]>

headers/private/shared/ScopeExit.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2022, Haiku, Inc. All Rights Reserved.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef _SCOPE_EXIT_H
+#define _SCOPE_EXIT_H
+
+
+#if __cplusplus < 201103L
+#error This file requires compiler support for the C++11 standard.
+#endif
+
+
+#include <utility>
+
+
+template<typename F>
+class ScopeExit
+{
+public:
+	explicit ScopeExit(F&& fn) : fFn(fn)
+	{
+	}
+
+	~ScopeExit()
+	{
+		fFn();
+	}
+
+	ScopeExit(ScopeExit&& other) : fFn(std::move(other.fFn))
+	{
+	}
+
+private:
+	ScopeExit(const ScopeExit&);
+	ScopeExit& operator=(const ScopeExit&);
+
+private:
+	F fFn;
+};
+
+
+#endif // _SCOPE_EXIT_H

src/system/kernel/arch/riscv64/arch_int.cpp

@@ -21,6 +21,7 @@
 #include <Plic.h>
 #include <Clint.h>
 #include <AutoDeleterDrivers.h>
+#include <ScopeExit.h>
 #include "RISCV64VMTranslationMap.h"
 
 #include <algorithm>
@@ -354,40 +355,6 @@ SetAccessedFlags(addr_t addr, bool isWrite)
 }
 
 
-// TODO: needs moved into an arch-agnostic location?
-
-template<typename F>
-class ScopeExit 
-{
-public:
-	explicit ScopeExit(F&& fn) : fFn(fn)
-	{
-	}
-
-	~ScopeExit()
-	{
-		fFn();
-	}
-
-	ScopeExit(ScopeExit&& other) : fFn(std::move(other.fFn))
-	{
-	}
-
-private:
-	ScopeExit(const ScopeExit&);
-	ScopeExit& operator=(const ScopeExit&);
-
-private:
-	F fFn;
-};
-
-template<typename F>
-ScopeExit<F> MakeScopeExit(F&& fn)
-{
-	return ScopeExit<F>(std::move(fn));
-}
-
-
 extern "C" void
 STrap(iframe* frame)
 {
@@ -428,7 +395,7 @@ STrap(iframe* frame)
 		thread_get_current_thread()->arch_info.oldA0 = frame->a0;
 		thread_at_kernel_entry(system_time());
 	}
-	const auto& kernelExit = MakeScopeExit([&]() {
+	const auto& kernelExit = ScopeExit([&]() {
 		if (SstatusReg(frame->status).spp == modeU) {
 			disable_interrupts();
 			atomic_and(&thread_get_current_thread()->flags, ~THREAD_FLAGS_SYSCALL_RESTARTED);