From db8b16641ce24636942e1d4649326f1fdf9981e2 Mon Sep 17 00:00:00 2001
From: Leonardo de Moura <leonardo@microsoft.com>
Date: Thu, 7 Nov 2013 17:22:28 -0800
Subject: [PATCH] chore(build): check if the Lua installed in the system
 supports lua_newstate

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
---
 src/CMakeLists.txt                    |  3 +++
 src/bindings/lua/leanlua_state.cpp    |  4 ++++
 src/cmake/Modules/CheckLuaNewstate.cc | 19 +++++++++++++++++++
 src/cmake/Modules/FindLua.cmake       | 16 ++++++++++++++++
 4 files changed, 42 insertions(+)
 create mode 100644 src/cmake/Modules/CheckLuaNewstate.cc

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 92ee77e32d..6895ccc650 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -126,6 +126,9 @@ if ("${LUA_FOUND}" MATCHES "TRUE")
   message(STATUS "Using Lua script language")
   set(EXTRA_LIBS ${EXTRA_LIBS} ${LUA_LIBRARIES})
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -I ${LUA_INCLUDE_DIR} -D LEAN_USE_LUA")
+  if ("${HAS_LUA_NEWSTATE}$" MATCHES "TRUE")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D LEAN_USE_LUA_NEWSTATE")
+  endif()
 else()
     message(WARNING "FAILED to find Lua script language, it will not be available")
 endif()
diff --git a/src/bindings/lua/leanlua_state.cpp b/src/bindings/lua/leanlua_state.cpp
index e58af96a6e..5cacfe06d4 100644
--- a/src/bindings/lua/leanlua_state.cpp
+++ b/src/bindings/lua/leanlua_state.cpp
@@ -29,7 +29,11 @@ struct leanlua_state::imp {
     std::mutex  m_mutex;
 
     imp() {
+        #ifdef LEAN_USE_LUA_NEWSTATE
         m_state = lua_newstate(lua_realloc, nullptr);
+        #else
+        m_state = luaL_newstate();
+        #endif
         if (m_state == nullptr)
             throw exception("fail to create Lua interpreter");
         luaL_openlibs(m_state);
diff --git a/src/cmake/Modules/CheckLuaNewstate.cc b/src/cmake/Modules/CheckLuaNewstate.cc
new file mode 100644
index 0000000000..c9884bd72b
--- /dev/null
+++ b/src/cmake/Modules/CheckLuaNewstate.cc
@@ -0,0 +1,19 @@
+/*
+Copyright (c) 2013 Microsoft Corporation. All rights reserved.
+Released under Apache 2.0 license as described in the file LICENSE.
+
+Author: Leonardo de Moura
+*/
+#include <iostream>
+#include <memory>
+#include <lua.hpp>
+
+static void * lua_realloc(void *, void * q, size_t, size_t sz) { return realloc(q, sz); }
+
+// Little program for checking whether lua_newstate is available
+int main() {
+    lua_State * L;
+    L = lua_newstate(lua_realloc, nullptr);
+    lua_close(L);
+    return 0;
+}
diff --git a/src/cmake/Modules/FindLua.cmake b/src/cmake/Modules/FindLua.cmake
index 31ddba6fd7..444ab8b791 100644
--- a/src/cmake/Modules/FindLua.cmake
+++ b/src/cmake/Modules/FindLua.cmake
@@ -115,3 +115,19 @@ FIND_PACKAGE_HANDLE_STANDARD_ARGS(Lua
                                   VERSION_VAR LUA_VERSION_STRING)
 
 MARK_AS_ADVANCED(LUA_INCLUDE_DIR LUA_LIBRARIES LUA_LIBRARY LUA_MATH_LIBRARY LUA_EXECUTABLE)
+
+# Print out version number
+if (LUA_FOUND)
+  try_run(LUA_CHECK LUA_CHECK_BUILD
+    ${LEAN_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeTmp
+    ${LEAN_SOURCE_DIR}/cmake/Modules/CheckLuaNewstate.cc
+    CMAKE_FLAGS -DINCLUDE_DIRECTORIES=${LUA_INCLUDE_DIR}
+    -DLINK_LIBRARIES=${LUA_LIBRARIES}
+    RUN_OUTPUT_VARIABLE LUA_TRY_OUT)
+  if ("${LUA_CHECK}" MATCHES "0" AND "${LUA_CHECK_BUILD}$" MATCHES "TRUE")
+    message(STATUS "lua_newstate works")
+    set(HAS_LUA_NEWSTATE TRUE)
+  else()
+    message(STATUS "lua_newstate is not supported by your Lua engine, Lean will not be able to track memory consumed by the Lua engine")
+  endif()
+endif ()