Upstream: Should be
Reason: Use pkgconfig to find luajit

diff --git a/cmake/Modules/FindLuaJIT.cmake b/cmake/Modules/FindLuaJIT.cmake
index 0d0786e..3ab8602 100644
--- a/cmake/Modules/FindLuaJIT.cmake
+++ b/cmake/Modules/FindLuaJIT.cmake
@@ -1,55 +1,72 @@
+# - Try to find LuaJIT
+# Once done this will define
+#
+#  LUAJIT_FOUND - system has LuaJIT
+#  LUAJIT_INCLUDE_DIR - the LuaJIT include directory
+#  LUAJIT_LIBRARIES - Link these to use LuaJIT
+#  LUAJIT_DEFINITIONS - Compiler switches required for using LuaJIT
+#
 #=============================================================================
-# Copyright 2007-2009 Kitware, Inc.
-# Copyright 2013 Rolf Eike Beer <eike@sf-mail.de>
+#  Copyright (c) 2016 Andrea Schneider <asn@cryptomilk.org>
 #
-# Distributed under the OSI-approved BSD License (the "License");
-# see accompanying file Copyright.txt for details.
+#  Distributed under the OSI-approved BSD License (the "License");
+#  see accompanying file Copyright.txt for details.
 #
-# This software is distributed WITHOUT ANY WARRANTY; without even the
-# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
-# See the License for more information.
+#  This software is distributed WITHOUT ANY WARRANTY; without even the
+#  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+#  See the License for more information.
 #=============================================================================
-# We use code from the CMake project to detect the Lua version.
-
-# Locate LuaJIT library
-# This module defines
-#  LUAJIT_FOUND, if false, do not try to link to Lua JIT
-#  LUAJIT_LIBRARIES
-#  LUAJIT_INCLUDE_DIR, where to find lua.h
 #
-# Additionally it defines the Lua API/ABI version:
-#  LUA_VERSION_STRING - the version of Lua found
-#  LUA_VERSION_MAJOR  - the major version of Lua
-#  LUA_VERSION_MINOR  - the minor version of Lua
-#  LUA_VERSION_PATCH  - the patch version of Lua
-
-FIND_PATH(LUAJIT_INCLUDE_DIR NAMES lua.h PATH_SUFFIXES luajit-2.0 luajit-2.1)
-FIND_LIBRARY(LUAJIT_LIBRARIES NAMES luajit-5.1 luajit)
-
-if (LUAJIT_INCLUDE_DIR AND EXISTS "${LUAJIT_INCLUDE_DIR}/lua.h")
-    # At least 5.[012] have different ways to express the version
-    # so all of them need to be tested. Lua 5.2 defines LUA_VERSION
-    # and LUA_RELEASE as joined by the C preprocessor, so avoid those.
-    file(STRINGS "${LUAJIT_INCLUDE_DIR}/lua.h" lua_version_strings
-         REGEX "^#define[ \t]+LUA_(RELEASE[ \t]+\"Lua [0-9]|VERSION([ \t]+\"Lua [0-9]|_[MR])).*")
-
-    string(REGEX REPLACE ".*;#define[ \t]+LUA_VERSION_MAJOR[ \t]+\"([0-9])\"[ \t]*;.*" "\\1" LUA_VERSION_MAJOR ";${lua_version_strings};")
-    if (LUA_VERSION_MAJOR MATCHES "^[0-9]+$")
-        string(REGEX REPLACE ".*;#define[ \t]+LUA_VERSION_MINOR[ \t]+\"([0-9])\"[ \t]*;.*" "\\1" LUA_VERSION_MINOR ";${lua_version_strings};")
-        string(REGEX REPLACE ".*;#define[ \t]+LUA_VERSION_RELEASE[ \t]+\"([0-9])\"[ \t]*;.*" "\\1" LUA_VERSION_PATCH ";${lua_version_strings};")
-        set(LUA_VERSION_STRING "${LUA_VERSION_MAJOR}.${LUA_VERSION_MINOR}.${LUA_VERSION_PATCH}")
-    else ()
-        string(REGEX REPLACE ".*;#define[ \t]+LUA_RELEASE[ \t]+\"Lua ([0-9.]+)\"[ \t]*;.*" "\\1" LUA_VERSION_STRING ";${lua_version_strings};")
-        if (NOT LUA_VERSION_STRING MATCHES "^[0-9.]+$")
-            string(REGEX REPLACE ".*;#define[ \t]+LUA_VERSION[ \t]+\"Lua ([0-9.]+)\"[ \t]*;.*" "\\1" LUA_VERSION_STRING ";${lua_version_strings};")
-        endif ()
-        string(REGEX REPLACE "^([0-9]+)\\.[0-9.]*$" "\\1" LUA_VERSION_MAJOR "${LUA_VERSION_STRING}")
-        string(REGEX REPLACE "^[0-9]+\\.([0-9]+)[0-9.]*$" "\\1" LUA_VERSION_MINOR "${LUA_VERSION_STRING}")
-        string(REGEX REPLACE "^[0-9]+\\.[0-9]+\\.([0-9]).*" "\\1" LUA_VERSION_PATCH "${LUA_VERSION_STRING}")
-    endif ()
-
-    unset(lua_version_strings)
-endif()
-
-INCLUDE(FindPackageHandleStandardArgs)
-FIND_PACKAGE_HANDLE_STANDARD_ARGS(LUAJIT DEFAULT_MSG LUAJIT_LIBRARIES LUAJIT_INCLUDE_DIR)
+
+if (UNIX)
+  find_package(PkgConfig)
+  if (PKG_CONFIG_FOUND)
+    pkg_check_modules(_LUAJIT luajit)
+  endif (PKG_CONFIG_FOUND)
+endif (UNIX)
+
+set(_LUAJIT_ROOT_HINTS
+    ${RSPAMD_SEARCH_PATH}
+    ${LUAJIT_ROOT_DIR}
+    ENV LUAJIT_ROOT_DIR
+)
+
+find_path(LUAJIT_INCLUDE_DIR
+    NAMES
+        luajit.h
+    PATHS
+        ${_LUAJIT_INCLUDEDIR}
+    HINTS
+        ${_LUAJIT_ROOT_HINTS}
+    PATH_SUFFIXES
+        luajit-5_1-2.0
+        luajit-5_2-2.0
+        luajit-5_3-2.0
+)
+
+find_library(LUAJIT_LIBRARY
+    NAMES
+        luajit
+        luajit-5.1
+        luajit-5.2
+        luajit-5.3
+    HINTS
+        ${_LUAJIT_ROOT_HINTS}
+    PATHS
+        ${_LUAJIT_LIBDIR}
+)
+
+if (LUAJIT_LIBRARY)
+    set(LUAJIT_LIBRARIES
+        ${LUAJIT_LIBRARIES}
+        ${LUAJIT_LIBRARY}
+    )
+endif (LUAJIT_LIBRARY)
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LuaJIT DEFAULT_MSG LUAJIT_LIBRARIES LUAJIT_INCLUDE_DIR)
+
+# show the LUAJIT_INCLUDE_DIR and LUAJIT_LIBRARIES variables only in the advanced view
+mark_as_advanced(LUAJIT_INCLUDE_DIR LUAJIT_LIBRARIES)
+
+