Move some Lua utility functions into a separate header file.

diff --git a/nageru/lua_utils.h b/nageru/lua_utils.h
new file mode 100644 (file)
index 0000000..102d7c5
--- /dev/null
+++ b/nageru/lua_utils.h
@@ -0,0 +1,77 @@
+#ifndef _LUA_UTILS_H
+#define _LUA_UTILS_H 1
+
+#include <lauxlib.h>
+#include <lua.hpp>
+
+#include <mutex>
+#include <utility>
+
+class LuaRefWithDeleter {
+public:
+       LuaRefWithDeleter(std::mutex *m, lua_State *L, int ref) : m(m), L(L), ref(ref) {}
+       ~LuaRefWithDeleter() {
+               std::lock_guard<std::mutex> lock(*m);
+               luaL_unref(L, LUA_REGISTRYINDEX, ref);
+       }
+       int get() const { return ref; }
+
+private:
+       LuaRefWithDeleter(const LuaRefWithDeleter &) = delete;
+
+       std::mutex *m;
+       lua_State *L;
+       int ref;
+};
+
+template<class T, class... Args>
+int wrap_lua_object(lua_State* L, const char *class_name, Args&&... args)
+{
+       // Construct the C++ object and put it on the stack.
+       void *mem = lua_newuserdata(L, sizeof(T));
+       new(mem) T(std::forward<Args>(args)...);
+
+       // Look up the metatable named <class_name>, and set it on the new object.
+       luaL_getmetatable(L, class_name);
+       lua_setmetatable(L, -2);
+
+       return 1;
+}
+
+// Like wrap_lua_object, but the object is not owned by Lua; ie. it's not freed
+// by Lua GC. This is typically the case for Effects, which are owned by EffectChain
+// and expected to be destructed by it. The object will be of type T** instead of T*
+// when exposed to Lua.
+//
+// Note that we currently leak if you allocate an Effect in this way and never call
+// add_effect. We should see if there's a way to e.g. set __gc on it at construction time
+// and then release that once add_effect() takes ownership.
+template<class T, class... Args>
+int wrap_lua_object_nonowned(lua_State* L, const char *class_name, Args&&... args)
+{
+       // Construct the pointer ot the C++ object and put it on the stack.
+       T **obj = (T **)lua_newuserdata(L, sizeof(T *));
+       *obj = new T(std::forward<Args>(args)...);
+
+       // Look up the metatable named <class_name>, and set it on the new object.
+       luaL_getmetatable(L, class_name);
+       lua_setmetatable(L, -2);
+
+       return 1;
+}
+
+template<class T>
+int wrap_lua_existing_object_nonowned(lua_State* L, const char *class_name, T *ptr)
+{
+       // Construct the pointer ot the C++ object and put it on the stack.
+       T **obj = (T **)lua_newuserdata(L, sizeof(T *));
+       *obj = ptr;
+
+       // Look up the metatable named <class_name>, and set it on the new object.
+       luaL_getmetatable(L, class_name);
+       lua_setmetatable(L, -2);
+
+       return 1;
+}
+
+#endif  // !defined(_LUA_UTILS_H)

diff --git a/nageru/theme.cpp b/nageru/theme.cpp
index 780c7cec3be04467d68c53061d3836deb0fac5e0..71a59a24525a8c123da024212e40d9395f5d1769 100644 (file)
--- a/nageru/theme.cpp
+++ b/nageru/theme.cpp
@@ -37,6 +37,7 @@
 #include "flags.h"
 #include "image_input.h"
 #include "input_state.h"
+#include "lua_utils.h"
 #include "pbo_frame_allocator.h"
 
 class Mixer;
@@ -115,59 +116,6 @@ InputStateInfo::InputStateInfo(const InputState &input_state)
        }
 }
 
-class LuaRefWithDeleter {
-public:
-       LuaRefWithDeleter(mutex *m, lua_State *L, int ref) : m(m), L(L), ref(ref) {}
-       ~LuaRefWithDeleter() {
-               lock_guard<mutex> lock(*m);
-               luaL_unref(L, LUA_REGISTRYINDEX, ref);
-       }
-       int get() const { return ref; }
-
-private:
-       LuaRefWithDeleter(const LuaRefWithDeleter &) = delete;
-
-       mutex *m;
-       lua_State *L;
-       int ref;
-};
-
-template<class T, class... Args>
-int wrap_lua_object(lua_State* L, const char *class_name, Args&&... args)
-{
-       // Construct the C++ object and put it on the stack.
-       void *mem = lua_newuserdata(L, sizeof(T));
-       new(mem) T(forward<Args>(args)...);
-
-       // Look up the metatable named <class_name>, and set it on the new object.
-       luaL_getmetatable(L, class_name);
-       lua_setmetatable(L, -2);
-
-       return 1;
-}
-
-// Like wrap_lua_object, but the object is not owned by Lua; ie. it's not freed
-// by Lua GC. This is typically the case for Effects, which are owned by EffectChain
-// and expected to be destructed by it. The object will be of type T** instead of T*
-// when exposed to Lua.
-//
-// Note that we currently leak if you allocate an Effect in this way and never call
-// add_effect. We should see if there's a way to e.g. set __gc on it at construction time
-// and then release that once add_effect() takes ownership.
-template<class T, class... Args>
-int wrap_lua_object_nonowned(lua_State* L, const char *class_name, Args&&... args)
-{
-       // Construct the pointer ot the C++ object and put it on the stack.
-       T **obj = (T **)lua_newuserdata(L, sizeof(T *));
-       *obj = new T(forward<Args>(args)...);
-
-       // Look up the metatable named <class_name>, and set it on the new object.
-       luaL_getmetatable(L, class_name);
-       lua_setmetatable(L, -2);
-
-       return 1;
-}
-
 enum EffectType {
        WHITE_BALANCE_EFFECT,
        RESAMPLE_EFFECT,