Merge branch 'fix-theoretical-lua-exposure-crashes' into 'next'

Fix some theoretical crashes when using the P_*XYMovement, P_*ZMovement, and P_RailThinker functions in Lua.

See merge request STJr/SRB2!1173

src/lua_baselib.c

@@ -913,44 +913,52 @@ static int lib_pMaceRotate(lua_State *L)
 static int lib_pRailThinker(lua_State *L)
 {
 	mobj_t *mobj = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
+	mobj_t *ptmthing = tmthing;
 	NOHUD
 	INLEVEL
 	if (!mobj)
 		return LUA_ErrInvalid(L, "mobj_t");
 	lua_pushboolean(L, P_RailThinker(mobj));
+	P_SetTarget(&tmthing, ptmthing);
 	return 1;
 }
 
 static int lib_pXYMovement(lua_State *L)
 {
 	mobj_t *actor = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
+	mobj_t *ptmthing = tmthing;
 	NOHUD
 	INLEVEL
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	P_XYMovement(actor);
+	P_SetTarget(&tmthing, ptmthing);
 	return 0;
 }
 
 static int lib_pRingXYMovement(lua_State *L)
 {
 	mobj_t *actor = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
+	mobj_t *ptmthing = tmthing;
 	NOHUD
 	INLEVEL
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	P_RingXYMovement(actor);
+	P_SetTarget(&tmthing, ptmthing);
 	return 0;
 }
 
 static int lib_pSceneryXYMovement(lua_State *L)
 {
 	mobj_t *actor = *((mobj_t **)luaL_checkudata(L, 1, META_MOBJ));
+	mobj_t *ptmthing = tmthing;
 	NOHUD
 	INLEVEL
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	P_SceneryXYMovement(actor);
+	P_SetTarget(&tmthing, ptmthing);
 	return 0;
 }
 
@@ -962,6 +970,7 @@ static int lib_pZMovement(lua_State *L)
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	lua_pushboolean(L, P_ZMovement(actor));
+	P_CheckPosition(actor, actor->x, actor->y);
 	return 1;
 }
 
@@ -973,6 +982,7 @@ static int lib_pRingZMovement(lua_State *L)
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	P_RingZMovement(actor);
+	P_CheckPosition(actor, actor->x, actor->y);
 	return 0;
 }
 
@@ -984,6 +994,7 @@ static int lib_pSceneryZMovement(lua_State *L)
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	lua_pushboolean(L, P_SceneryZMovement(actor));
+	P_CheckPosition(actor, actor->x, actor->y);
 	return 1;
 }
 
@@ -995,6 +1006,7 @@ static int lib_pPlayerZMovement(lua_State *L)
 	if (!actor)
 		return LUA_ErrInvalid(L, "mobj_t");
 	P_PlayerZMovement(actor);
+	P_CheckPosition(actor, actor->x, actor->y);
 	return 0;
 }