Implement mod communication channels (#6351)

Implement network communication for channels

* Implement ModChannel manager server side to route incoming messages from clients to other clients
* Add signal handler switch on client & ModChannelMgr on client to handle channels
* Add Lua API bindings + client packet sending + unittests
* Implement server message sending
* Add callback from received message handler to Lua API using registration method

3 files changed, 107 insertions, 1 deletions

diff --git a/src/unittest/CMakeLists.txt b/src/unittest/CMakeLists.txt
index 7ad38099c..3a4450fac 100644
--- a/src/unittest/CMakeLists.txt
+++ b/src/unittest/CMakeLists.txt
@@ -8,6 +8,7 @@ set (UNITTEST_SRCS
 	${CMAKE_CURRENT_SOURCE_DIR}/test_inventory.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_map_settings_manager.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_mapnode.cpp
+	${CMAKE_CURRENT_SOURCE_DIR}/test_modchannels.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_nodedef.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_noderesolver.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/test_noise.cpp
diff --git a/src/unittest/test.cpp b/src/unittest/test.cpp
index 84fad41ce..1985fdc6c 100644
--- a/src/unittest/test.cpp
+++ b/src/unittest/test.cpp
@@ -22,6 +22,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "nodedef.h"
 #include "itemdef.h"
 #include "gamedef.h"
+#include "modchannels.h"
 #include "mods.h"
 #include "util/numeric.h"
 
@@ -69,6 +70,13 @@ public:
 	virtual std::string getModStoragePath() const { return "."; }
 	virtual bool registerModStorage(ModMetadata *meta) { return true; }
 	virtual void unregisterModStorage(const std::string &name) {}
+	bool joinModChannel(const std::string &channel);
+	bool leaveModChannel(const std::string &channel);
+	bool sendModChannelMessage(const std::string &channel, const std::string &message);
+	ModChannel *getModChannel(const std::string &channel)
+	{
+		return m_modchannel_mgr->getModChannel(channel);
+	}
 
 private:
 	IItemDefManager *m_itemdef = nullptr;
@@ -81,10 +89,12 @@ private:
 	scene::ISceneManager *m_scenemgr = nullptr;
 	IRollbackManager *m_rollbackmgr = nullptr;
 	EmergeManager *m_emergemgr = nullptr;
+	std::unique_ptr<ModChannelMgr> m_modchannel_mgr;
 };
 
 
-TestGameDef::TestGameDef()
+TestGameDef::TestGameDef() :
+	m_modchannel_mgr(new ModChannelMgr())
 {
 	m_itemdef = createItemDefManager();
 	m_nodedef = createNodeDefManager();
@@ -222,6 +232,25 @@ void TestGameDef::defineSomeNodes()
 	t_CONTENT_BRICK = ndef->set(f.name, f);
 }
 
+bool TestGameDef::joinModChannel(const std::string &channel)
+{
+	return m_modchannel_mgr->joinChannel(channel, PEER_ID_SERVER);
+}
+
+bool TestGameDef::leaveModChannel(const std::string &channel)
+{
+	return m_modchannel_mgr->leaveChannel(channel, PEER_ID_SERVER);
+}
+
+bool TestGameDef::sendModChannelMessage(const std::string &channel,
+	const std::string &message)
+{
+	if (!m_modchannel_mgr->channelRegistered(channel))
+		return false;
+
+	return true;
+}
+
 ////
 //// run_tests
 ////
diff --git a/src/unittest/test_modchannels.cpp b/src/unittest/test_modchannels.cpp
new file mode 100644
index 000000000..069f439a1
--- /dev/null
+++ b/src/unittest/test_modchannels.cpp
@@ -0,0 +1,76 @@
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 2.1 of the License, or
+(at your option) any later version.
+
+This program 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 Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public License along
+with this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "test.h"
+
+#include "gamedef.h"
+#include "modchannels.h"
+
+class TestModChannels : public TestBase
+{
+public:
+	TestModChannels() { TestManager::registerTestModule(this); }
+	const char *getName() { return "TestModChannels"; }
+
+	void runTests(IGameDef *gamedef);
+
+	void testJoinChannel(IGameDef *gamedef);
+	void testLeaveChannel(IGameDef *gamedef);
+	void testSendMessageToChannel(IGameDef *gamedef);
+};
+
+static TestModChannels g_test_instance;
+
+void TestModChannels::runTests(IGameDef *gamedef)
+{
+	TEST(testJoinChannel, gamedef);
+	TEST(testLeaveChannel, gamedef);
+	TEST(testSendMessageToChannel, gamedef);
+}
+
+void TestModChannels::testJoinChannel(IGameDef *gamedef)
+{
+	// Test join
+	UASSERT(gamedef->joinModChannel("test_join_channel"));
+	// Test join (fail, already join)
+	UASSERT(!gamedef->joinModChannel("test_join_channel"));
+}
+
+void TestModChannels::testLeaveChannel(IGameDef *gamedef)
+{
+	// Test leave (not joined)
+	UASSERT(!gamedef->leaveModChannel("test_leave_channel"));
+
+	UASSERT(gamedef->joinModChannel("test_leave_channel"));
+
+	// Test leave (joined)
+	UASSERT(gamedef->leaveModChannel("test_leave_channel"));
+}
+
+void TestModChannels::testSendMessageToChannel(IGameDef *gamedef)
+{
+	// Test sendmsg (not joined)
+	UASSERT(!gamedef->sendModChannelMessage(
+			"test_sendmsg_channel", "testmsgchannel"));
+
+	UASSERT(gamedef->joinModChannel("test_sendmsg_channel"));
+
+	// Test sendmsg (joined)
+	UASSERT(gamedef->sendModChannelMessage("test_sendmsg_channel", "testmsgchannel"));
+}