libardour lua-script-manager

1 files changed, 381 insertions, 0 deletions

diff --git a/libs/ardour/luascripting.cc b/libs/ardour/luascripting.cc
new file mode 100644
index 0000000000..d3768c17d5
--- /dev/null
+++ b/libs/ardour/luascripting.cc
@@ -0,0 +1,381 @@
+/*
+ * Copyright (C) 2016 Robin Gareus <robin@gareus.org>
+ *
+ * This program 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 2
+ * 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU 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 <cstring>
+
+#include "pbd/error.h"
+#include "pbd/file_utils.h"
+#include "pbd/compose.h"
+
+#include "ardour/luascripting.h"
+#include "ardour/search_paths.h"
+
+#include "lua/luastate.h"
+#include "LuaBridge/LuaBridge.h"
+
+#include "i18n.h"
+
+using namespace ARDOUR;
+using namespace PBD;
+using namespace std;
+
+LuaScripting* LuaScripting::_instance = 0;
+
+LuaScripting&
+LuaScripting::instance ()
+{
+	if (!_instance) {
+		_instance = new LuaScripting;
+	}
+	return *_instance;
+}
+
+LuaScripting::LuaScripting ()
+	: _sl_dsp (0)
+	, _sl_session (0)
+	, _sl_hook (0)
+	, _sl_action (0)
+{
+	;
+}
+
+LuaScripting::~LuaScripting ()
+{
+	if (getenv ("ARDOUR_RUNNING_UNDER_VALGRIND")) {
+		// don't bother, just exit quickly.
+		delete _sl_dsp;
+		delete _sl_session;
+		delete _sl_hook;
+		delete _sl_action;
+	}
+}
+
+void
+LuaScripting::check_scan ()
+{
+	if (!_sl_dsp || !_sl_session || !_sl_hook || !_sl_action) {
+		scan ();
+	}
+}
+
+void
+LuaScripting::refresh ()
+{
+	Glib::Threads::Mutex::Lock lm (_lock, Glib::Threads::TRY_LOCK);
+
+	if (!lm.locked()) {
+		return;
+	}
+
+	delete _sl_dsp;
+	delete _sl_session;
+	delete _sl_hook;
+	delete _sl_action;
+
+	_sl_dsp = 0;
+	_sl_session = 0;
+	_sl_hook = 0;
+	_sl_action = 0;
+}
+
+struct ScriptSorter {
+	bool operator () (LuaScriptInfoPtr a, LuaScriptInfoPtr b) {
+		return a->name < b->name;
+	}
+};
+
+void
+LuaScripting::scan ()
+{
+	Glib::Threads::Mutex::Lock lm (_lock, Glib::Threads::TRY_LOCK);
+
+	if (!lm.locked()) {
+		return;
+	}
+
+#define CLEAR_OR_NEW(LIST) \
+	if (LIST) { LIST->clear (); } else { LIST = new LuaScriptList (); }
+
+	CLEAR_OR_NEW (_sl_dsp)
+	CLEAR_OR_NEW (_sl_session)
+	CLEAR_OR_NEW (_sl_hook)
+	CLEAR_OR_NEW (_sl_action)
+
+#undef CLEAR_OR_NEW
+
+	vector<string> luascripts;
+	find_files_matching_pattern (luascripts, lua_search_path (), "*.lua");
+
+	for (vector<string>::iterator i = luascripts.begin(); i != luascripts.end (); ++i) {
+		LuaScriptInfoPtr lsi = scan_script (*i);
+		if (!lsi) {
+			PBD::info << string_compose (_("Script '%1' has no valid descriptor."), *i) << endmsg;
+			continue;
+		}
+		switch (lsi->type) {
+			case LuaScriptInfo::DSP:
+				_sl_dsp->push_back(lsi);
+				break;
+			case LuaScriptInfo::Session:
+				_sl_session->push_back(lsi);
+				break;
+			case LuaScriptInfo::EditorHook:
+				_sl_hook->push_back(lsi);
+				break;
+			case LuaScriptInfo::EditorAction:
+				_sl_action->push_back(lsi);
+				break;
+			default:
+				break;
+		}
+	}
+
+	std::sort (_sl_dsp->begin(), _sl_dsp->end(), ScriptSorter());
+	std::sort (_sl_session->begin(), _sl_session->end(), ScriptSorter());
+	std::sort (_sl_hook->begin(), _sl_hook->end(), ScriptSorter());
+	std::sort (_sl_action->begin(), _sl_action->end(), ScriptSorter());
+
+}
+
+void
+LuaScripting::lua_print (std::string s) {
+	PBD::info << "Lua: " << s << "\n";
+}
+
+LuaScriptInfoPtr
+LuaScripting::scan_script (const std::string &fn, const std::string &sc)
+{
+	LuaState lua;
+	if (!(fn.empty() ^ sc.empty())){
+		// give either file OR script
+		assert (0);
+		return LuaScriptInfoPtr();
+	}
+
+	lua_State* L = lua.getState();
+	lua.Print.connect (&LuaScripting::lua_print);
+
+	lua.do_command ("io = nil;");
+
+	lua.do_command (
+			"ardourluainfo = {}"
+			"function ardour (entry)"
+			"  ardourluainfo['type'] = assert(entry['type'])"
+			"  ardourluainfo['name'] = assert(entry['name'])"
+			"  ardourluainfo['author'] = entry['author'] or 'Unknown'"
+			"  ardourluainfo['license'] = entry['license'] or ''"
+			"  ardourluainfo['description'] = entry['description'] or ''"
+			" end"
+			);
+
+	try {
+		int err;
+		if (fn.empty()) {
+			err = lua.do_command (sc);
+		} else {
+			err = lua.do_file (fn);
+		}
+		if (err) {
+			return LuaScriptInfoPtr();
+		}
+	} catch (...) { // luabridge::LuaException
+		return LuaScriptInfoPtr();
+	}
+	luabridge::LuaRef nfo = luabridge::getGlobal (L, "ardourluainfo");
+	if (nfo.type() != LUA_TTABLE) {
+		return LuaScriptInfoPtr();
+	}
+
+	if (nfo["name"].type() != LUA_TSTRING || nfo["type"].type() != LUA_TSTRING) {
+		return LuaScriptInfoPtr();
+	}
+
+	std::string name = nfo["name"].cast<std::string>();
+	LuaScriptInfo::ScriptType type = LuaScriptInfo::str2type (nfo["type"].cast<std::string>());
+
+	if (name.empty() || type == LuaScriptInfo::Invalid) {
+		return LuaScriptInfoPtr();
+	}
+
+	LuaScriptInfoPtr lsi (new LuaScriptInfo (type, name, fn));
+
+	for (luabridge::Iterator i(nfo); !i.isNil (); ++i) {
+		if (!i.key().isString() || !i.value().isString()) {
+			return LuaScriptInfoPtr();
+		}
+		std::string key = i.key().tostring();
+		std::string val = i.value().tostring();
+
+		if (key == "author") { lsi->author = val; }
+		if (key == "license") { lsi->license = val; }
+		if (key == "description") { lsi->description = val; }
+	}
+
+	return lsi;
+}
+
+LuaScriptList &
+LuaScripting::scripts (LuaScriptInfo::ScriptType type) {
+	check_scan();
+
+	switch (type) {
+		case LuaScriptInfo::DSP:
+			return *_sl_dsp;
+			break;
+		case LuaScriptInfo::Session:
+			return *_sl_session;
+			break;
+		case LuaScriptInfo::EditorHook:
+			return *_sl_hook;
+			break;
+		case LuaScriptInfo::EditorAction:
+			return *_sl_action;
+			break;
+		default:
+			return _empty_script_info;
+			break;
+	}
+}
+
+
+std::string
+LuaScriptInfo::type2str (const ScriptType t) {
+	switch (t) {
+		case LuaScriptInfo::DSP: return "DSP";
+		case LuaScriptInfo::Session: return "Session";
+		case LuaScriptInfo::EditorHook: return "EditorHook";
+		case LuaScriptInfo::EditorAction: return "EditorAction";
+		default: return "Invalid";
+	}
+}
+
+LuaScriptInfo::ScriptType
+LuaScriptInfo::str2type (const std::string& str) {
+	const char* type = str.c_str();
+	if (!strcasecmp (type, "DSP")) {return LuaScriptInfo::DSP;}
+	if (!strcasecmp (type, "Session")) {return LuaScriptInfo::Session;}
+	if (!strcasecmp (type, "EditorHook")) {return LuaScriptInfo::EditorHook;}
+	if (!strcasecmp (type, "EditorAction")) {return LuaScriptInfo::EditorAction;}
+	return LuaScriptInfo::Invalid;
+}
+
+LuaScriptParamList
+LuaScripting::script_params (LuaScriptInfoPtr lsi, const std::string &fn)
+{
+	LuaScriptParamList rv;
+	assert (lsi);
+
+	LuaState lua;
+	lua_State* L = lua.getState();
+	lua.Print.connect (&LuaScripting::lua_print);
+	lua.do_command ("io = nil;");
+	lua.do_command ("function ardour () end");
+
+	try {
+		lua.do_file (lsi->path);
+	} catch (luabridge::LuaException const& e) {
+		return rv;
+	}
+
+	luabridge::LuaRef lua_params = luabridge::getGlobal (L, fn.c_str());
+	if (lua_params.isFunction ()) {
+		luabridge::LuaRef params = lua_params ();
+		if (params.isTable ()) {
+			for (luabridge::Iterator i (params); !i.isNil (); ++i) {
+				if (!i.key ().isString ())            { continue; }
+				if (!i.value ().isTable ())           { continue; }
+				if (!i.value ()["title"].isString ()) { continue; }
+
+				std::string name = i.key ().cast<std::string> ();
+				std::string title = i.value ()["title"].cast<std::string> ();
+				std::string dflt;
+				bool optional = false;
+
+				if (i.value ()["default"].isString ()) {
+					dflt = i.value ()["default"].cast<std::string> ();
+				}
+				if (i.value ()["optional"].isBoolean ()) {
+					optional = i.value ()["optional"].cast<bool> ();
+				}
+				LuaScriptParamPtr lsspp (new LuaScriptParam(name, title, dflt, optional));
+				rv.push_back (lsspp);
+			}
+		}
+	}
+	return rv;
+}
+
+bool
+LuaScripting::try_compile (const std::string& script, const LuaScriptParamList& args)
+{
+	const std::string& bytecode = get_factory_bytecode (script);
+	if (bytecode.empty()) {
+		return false;
+	}
+	LuaState l;
+	lua_State* L = l.getState();
+
+	l.do_command (""
+			" function checkfactory (b, a)"
+			"  assert(type(b) == 'string', 'ByteCode must be string')"
+			"  load(b)()"
+			"  assert(type(f) == 'string', 'Assigned ByteCode must be string')"
+			"  local env = _ENV;  env.f = nil env.debug = nil os.exit = nil"
+			"  load (string.dump(f, true), nil, nil, env)(a)"
+			" end"
+			);
+
+	try {
+		luabridge::LuaRef lua_test = luabridge::getGlobal (L, "checkfactory");
+		l.do_command ("checkfactory = nil"); // hide it.
+		l.do_command ("collectgarbage()");
+		lua_test (bytecode);
+		return true; // OK
+	} catch (luabridge::LuaException const& e) { }
+
+	return false;
+}
+
+std::string
+LuaScripting::get_factory_bytecode (const std::string& script)
+{
+	LuaState l;
+	l.Print.connect (&LuaScripting::lua_print);
+	lua_State* L = l.getState();
+
+	l.do_command (
+			" function ardour () end"
+			""
+			" function dump_function (f)"
+			"  assert(type(f) == 'function', 'Factory is a not a function')"
+			"  return string.format(\"f = %q\", string.dump(f, true))"
+			" end"
+			);
+
+	try {
+		luabridge::LuaRef lua_dump = luabridge::getGlobal (L, "dump_function");
+		l.do_command ("dump_function = nil"); // hide it
+		l.do_command (script); // register "factory"
+		luabridge::LuaRef lua_factory = luabridge::getGlobal (L, "factory");
+
+		if (lua_factory.isFunction()) {
+			return (lua_dump(lua_factory)).cast<std::string> ();
+		}
+	} catch (luabridge::LuaException const& e) { }
+	return "";
+}