[CSM] Client side modding

* rename GameScripting to ServerScripting
* Make getBuiltinLuaPath static serverside
* Add on_shutdown callback
* Add on_receiving_chat_message & on_sending_chat_message callbacks
* ScriptApiBase: use IGameDef instead of Server
  This permits to share common attribute between client & server
* Enable mod security in client side modding without conditions

6 files changed, 132 insertions, 13 deletions

diff --git a/src/script/cpp_api/CMakeLists.txt b/src/script/cpp_api/CMakeLists.txt
index be4d0131e..4b13356a8 100644
--- a/src/script/cpp_api/CMakeLists.txt
+++ b/src/script/cpp_api/CMakeLists.txt
@@ -13,6 +13,7 @@ set(common_SCRIPT_CPP_API_SRCS
 	PARENT_SCOPE)
 
 set(client_SCRIPT_CPP_API_SRCS
+	${CMAKE_CURRENT_SOURCE_DIR}/s_client.cpp
 	${CMAKE_CURRENT_SOURCE_DIR}/s_mainmenu.cpp
 	PARENT_SCOPE)
 
diff --git a/src/script/cpp_api/s_base.cpp b/src/script/cpp_api/s_base.cpp
index cbe5735a7..6a843810f 100644
--- a/src/script/cpp_api/s_base.cpp
+++ b/src/script/cpp_api/s_base.cpp
@@ -23,12 +23,14 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 #include "lua_api/l_object.h"
 #include "common/c_converter.h"
 #include "serverobject.h"
-#include "debug.h"
 #include "filesys.h"
-#include "log.h"
 #include "mods.h"
 #include "porting.h"
 #include "util/string.h"
+#include "server.h"
+#ifndef SERVER
+#include "client.h"
+#endif
 
 
 extern "C" {
@@ -69,7 +71,8 @@ public:
 */
 
 ScriptApiBase::ScriptApiBase() :
-	m_luastackmutex()
+	m_luastackmutex(),
+	m_gamedef(NULL)
 {
 #ifdef SCRIPTAPI_LOCK_DEBUG
 	m_lock_recursion_count = 0;
@@ -113,7 +116,6 @@ ScriptApiBase::ScriptApiBase() :
 	// Default to false otherwise
 	m_secure = false;
 
-	m_server = NULL;
 	m_environment = NULL;
 	m_guiengine = NULL;
 }
@@ -333,3 +335,14 @@ void ScriptApiBase::objectrefGet(lua_State *L, u16 id)
 	lua_remove(L, -2); // object_refs
 	lua_remove(L, -2); // core
 }
+
+Server* ScriptApiBase::getServer()
+{
+	return dynamic_cast<Server *>(m_gamedef);
+}
+#ifndef SERVER
+Client* ScriptApiBase::getClient()
+{
+	return dynamic_cast<Client *>(m_gamedef);
+}
+#endif
diff --git a/src/script/cpp_api/s_base.h b/src/script/cpp_api/s_base.h
index c27235255..19d71df65 100644
--- a/src/script/cpp_api/s_base.h
+++ b/src/script/cpp_api/s_base.h
@@ -55,6 +55,10 @@ extern "C" {
 	setOriginFromTableRaw(index, __FUNCTION__)
 
 class Server;
+#ifndef SERVER
+class Client;
+#endif
+class IGameDef;
 class Environment;
 class GUIEngine;
 class ServerActiveObject;
@@ -75,7 +79,11 @@ public:
 	void addObjectReference(ServerActiveObject *cobj);
 	void removeObjectReference(ServerActiveObject *cobj);
 
-	Server* getServer() { return m_server; }
+	IGameDef *getGameDef() { return m_gamedef; }
+	Server* getServer();
+#ifndef SERVER
+	Client* getClient();
+#endif
 
 	std::string getOrigin() { return m_last_run_mod; }
 	void setOriginDirect(const char *origin);
@@ -98,7 +106,7 @@ protected:
 	void scriptError(int result, const char *fxn);
 	void stackDump(std::ostream &o);
 
-	void setServer(Server* server) { m_server = server; }
+	void setGameDef(IGameDef* gamedef) { m_gamedef = gamedef; }
 
 	Environment* getEnv() { return m_environment; }
 	void setEnv(Environment* env) { m_environment = env; }
@@ -122,7 +130,7 @@ private:
 
 	lua_State*      m_luastack;
 
-	Server*         m_server;
+	IGameDef*       m_gamedef;
 	Environment*    m_environment;
 	GUIEngine*      m_guiengine;
 };
diff --git a/src/script/cpp_api/s_client.cpp b/src/script/cpp_api/s_client.cpp
new file mode 100644
index 000000000..08af8ebdc
--- /dev/null
+++ b/src/script/cpp_api/s_client.cpp
@@ -0,0 +1,61 @@
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 nerzhul, Loic Blot <loic.blot@unix-experience.fr>
+
+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 "s_client.h"
+#include "s_internal.h"
+
+void ScriptApiClient::on_shutdown()
+{
+	SCRIPTAPI_PRECHECKHEADER
+
+	// Get registered shutdown hooks
+	lua_getglobal(L, "core");
+	lua_getfield(L, -1, "registered_on_shutdown");
+	// Call callbacks
+	runCallbacks(0, RUN_CALLBACKS_MODE_FIRST);
+}
+
+bool ScriptApiClient::on_sending_message(const std::string &message)
+{
+	SCRIPTAPI_PRECHECKHEADER
+
+	// Get core.registered_on_chat_messages
+	lua_getglobal(L, "core");
+	lua_getfield(L, -1, "registered_on_sending_chat_messages");
+	// Call callbacks
+	lua_pushstring(L, message.c_str());
+	runCallbacks(1, RUN_CALLBACKS_MODE_OR_SC);
+	bool ate = lua_toboolean(L, -1);
+	return ate;
+}
+
+bool ScriptApiClient::on_receiving_message(const std::string &message)
+{
+	SCRIPTAPI_PRECHECKHEADER
+
+	// Get core.registered_on_chat_messages
+	lua_getglobal(L, "core");
+	lua_getfield(L, -1, "registered_on_receiving_chat_messages");
+	// Call callbacks
+	lua_pushstring(L, message.c_str());
+	runCallbacks(1, RUN_CALLBACKS_MODE_OR_SC);
+	bool ate = lua_toboolean(L, -1);
+	return ate;
+}
diff --git a/src/script/cpp_api/s_client.h b/src/script/cpp_api/s_client.h
new file mode 100644
index 000000000..08fdd8fc0
--- /dev/null
+++ b/src/script/cpp_api/s_client.h
@@ -0,0 +1,36 @@
+/*
+Minetest
+Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
+Copyright (C) 2017 nerzhul, Loic Blot <loic.blot@unix-experience.fr>
+
+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.
+*/
+
+#ifndef S_CLIENT_H_
+#define S_CLIENT_H_
+
+#include "cpp_api/s_base.h"
+
+class ScriptApiClient: virtual public ScriptApiBase
+{
+public:
+	// Calls on_shutdown handlers
+	void on_shutdown();
+
+	// Chat message handlers
+	bool on_sending_message(const std::string &message);
+	bool on_receiving_message(const std::string &message);
+};
+#endif
diff --git a/src/script/cpp_api/s_security.cpp b/src/script/cpp_api/s_security.cpp
index be2b884cc..f85cd0c9c 100644
--- a/src/script/cpp_api/s_security.cpp
+++ b/src/script/cpp_api/s_security.cpp
@@ -382,9 +382,9 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
 	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_SCRIPTAPI);
 	ScriptApiBase *script = (ScriptApiBase *) lua_touserdata(L, -1);
 	lua_pop(L, 1);
-	const Server *server = script->getServer();
-
-	if (!server) return false;
+	const IGameDef *gamedef = script->getGameDef();
+	if (!gamedef)
+		return false;
 
 	// Get mod name
 	lua_rawgeti(L, LUA_REGISTRYINDEX, CUSTOM_RIDX_CURRENT_MOD_NAME);
@@ -400,7 +400,7 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
 		// Allow paths in mod path
 		// Don't bother if write access isn't important, since it will be handled later
 		if (write_required || write_allowed != NULL) {
-			const ModSpec *mod = server->getModSpec(mod_name);
+			const ModSpec *mod = gamedef->getModSpec(mod_name);
 			if (mod) {
 				str = fs::AbsolutePath(mod->path);
 				if (!str.empty() && fs::PathStartsWith(abs_path, str)) {
@@ -414,7 +414,7 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
 
 	// Allow read-only access to all mod directories
 	if (!write_required) {
-		const std::vector<ModSpec> mods = server->getMods();
+		const std::vector<ModSpec> mods = gamedef->getMods();
 		for (size_t i = 0; i < mods.size(); ++i) {
 			str = fs::AbsolutePath(mods[i].path);
 			if (!str.empty() && fs::PathStartsWith(abs_path, str)) {
@@ -423,7 +423,7 @@ bool ScriptApiSecurity::checkPath(lua_State *L, const char *path,
 		}
 	}
 
-	str = fs::AbsolutePath(server->getWorldPath());
+	str = fs::AbsolutePath(gamedef->getWorldPath());
 	if (!str.empty()) {
 		// Don't allow access to other paths in the world mod/game path.
 		// These have to be blocked so you can't override a trusted mod