atomic workaround

3 files changed, 188 insertions, 1 deletions

diff --git a/src/atomic.h b/src/atomic.h
new file mode 100644
index 0000000..11c87fc
--- /dev/null
+++ b/src/atomic.h
@@ -0,0 +1,105 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            atomic.h
+ *
+ *  Wed Mar 23 09:15:05 CET 2016
+ *  Copyright 2016 Christian Glöckner
+ *  cgloeckner@freenet.de
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#pragma once
+
+#include <type_traits>
+#include <atomic>
+#include <mutex>
+
+template <typename T, typename = void>
+class Atomic;
+
+// use std::atomic if possible
+template <typename T>
+class Atomic<T, typename std::enable_if<std::is_trivially_copyable<T>::value>::type>
+	: public std::atomic<T> {
+};
+
+// else work around it using a mutex
+template <typename T>
+class Atomic<T, typename std::enable_if<!std::is_trivially_copyable<T>::value>::type> {
+	public:
+		using self_type = Atomic<T, typename std::enable_if<!std::is_trivially_copyable<T>::value>::type>;
+
+		Atomic()
+			: data{}
+			, mutex{} {
+		}
+
+		Atomic(T data)
+			: data{std::move(data)}
+			, mutex{} {
+		}
+
+		Atomic(self_type const & other)
+			: data{}
+			, mutex{} {
+			std::lock_guard<std::mutex> lock{other.mutex};
+			data = other.data;
+		}
+
+		Atomic(self_type&& other)
+			: data{}
+			, mutex{} {
+			std::lock_guard<std::mutex> lock{other.mutex};
+			std::swap(data, other.data);
+		}
+
+		T operator=(T data) {
+			std::lock_guard<std::mutex> lock{mutex};
+			this->data = std::move(data);
+			return this->data;
+		}
+
+		operator T() const {
+			return load();
+		}
+
+		bool is_lock_free() const {
+			return false;
+		}
+
+		void store(T data) {
+			std::lock_guard<std::mutex> lock{mutex};
+			this->data = std::move(data);
+		}
+
+		T load() const {
+			std::lock_guard<std::mutex> lock{mutex};
+			return data;
+		}
+
+		T exchange(T data){
+			std::lock_guard<std::mutex> lock{mutex};
+			std::swap(data, this->data);
+			return data;
+		}
+
+	private:
+		T data;
+		mutable std::mutex mutex;
+};
diff --git a/test/Makefile.am b/test/Makefile.am
index 6e56043..4209991 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -3,7 +3,7 @@ include $(top_srcdir)/src/Makefile.am.drumgizmo
 
 TESTS = resource engine gui resampler lv2 configfile audiocache \
 	audiocachefile audiocacheidmanager audiocacheeventhandler \
-	memchecker
+	memchecker atomictest
 
 check_PROGRAMS = $(TESTS)
 
@@ -128,5 +128,10 @@ memchecker_SOURCES = \
 	test.cc \
 	memcheckertest.cc
 
+atomictest_CXXFLAGS = -DOUTPUT=\"atomictest\" $(CPPUNIT_CFLAGS) \
+	-I$(top_srcdir)/src -I$(top_srcdir)/hugin
+atomictest_LDFLAGS = $(CPPUNIT_LIBS)
+atomictest_SOURCES = atomictest.cc test.cc
+
 EXTRA_DIST = \
 	lv2_test_host.h
diff --git a/test/atomictest.cc b/test/atomictest.cc
new file mode 100644
index 0000000..d4cacf0
--- /dev/null
+++ b/test/atomictest.cc
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/***************************************************************************
+ *            atomic.cc
+ *
+ *  Wed Mar 23 09:17:12 CET 2016
+ *  Copyright 2016 Christian Glöckner
+ *  cgloeckner@freenet.de
+ ****************************************************************************/
+
+/*
+ *  This file is part of DrumGizmo.
+ *
+ *  DrumGizmo is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  DrumGizmo is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with DrumGizmo; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
+ */
+#include <cppunit/extensions/HelperMacros.h>
+
+#include <atomic.h>
+
+class AtomicTest
+	: public CppUnit::TestFixture {
+		
+	CPPUNIT_TEST_SUITE(AtomicTest);
+	CPPUNIT_TEST(atomicIntUsesStandardImpl);
+	CPPUNIT_TEST(atomicFloatUsesStandardImpl);
+	CPPUNIT_TEST(atomicBoolUsesStandardImpl);
+	CPPUNIT_TEST(atomicStringCanBeUsed);
+	CPPUNIT_TEST_SUITE_END();
+	
+	public:
+		void setUp() {}
+		void tearDown() {}
+		
+		void atomicIntUsesStandardImpl() {
+			CPPUNIT_ASSERT(isUsingStandardImpl<int>());
+		}
+		
+		void atomicFloatUsesStandardImpl() {
+			CPPUNIT_ASSERT(isUsingStandardImpl<float>());
+		}
+		
+		void atomicBoolUsesStandardImpl() {
+			CPPUNIT_ASSERT(isUsingStandardImpl<bool>());
+		}
+		
+		void atomicDoubleUsesStandardImpl() {
+			CPPUNIT_ASSERT(isUsingStandardImpl<double>());
+		}
+		
+		void atomicStringCanBeUsed() {
+			// note: if it couldn't be used, the compiler would complain
+			Atomic<std::string> tmp;
+		}
+		
+		// todo: further testing
+		
+	private:
+		template <typename T>
+		bool isUsingStandardImpl() {
+			return std::is_base_of<std::atomic<T>, Atomic<T>>::value;
+		}
+};
+
+// Registers the fixture into the 'registry'
+CPPUNIT_TEST_SUITE_REGISTRATION(AtomicTest);
+