rockspec: propagate CMake options

Sometimes one needs to build a luzer module using rockspec with
a non-system Lua library and headers or set other CMake options
before building. The patch adds variables for the rockspec to set
the following CMake options via environment variables:
ENABLE_LUAJIT, LUAJIT_FRIENDLY_MODE and OSS_FUZZ:

luarocks install --tree=lua_modules luzer-scm-1.rockspec \
  ENABLE_LUAJIT=ON LUAJIT_FRIENDLY_MODE=ON

The patch also renames CMake variables used for setting a custom
Lua library and Lua include directory: LUA_LIBRARIES to
CMAKE_LUA_LIBRARIES and LUA_INCLUDE_DIR to CMAKE_LUA_INCLUDE_DIR.
This is needed because with empty environment variables
LUA_LIBRARIES and LUA_INCLUDE_DIR passed to luarocks breaks CMake
module for finding Lua package:

CMake Error at /usr/share/cmake-3.28/Modules/FindPackageHandleStandardArgs.cmake:230 (message):
  Could NOT find Lua (missing: LUA_LIBRARIES LUA_INCLUDE_DIR) (Required is at least version "5.1")
Call Stack (most recent call first):
  /usr/share/cmake-3.28/Modules/FindPackageHandleStandardArgs.cmake:600 (_FPHSA_FAILURE_MESSAGE)
  /usr/share/cmake-3.28/Modules/FindLua.cmake:236 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
  CMakeLists.txt:49 (find_package)

After renaming these options can be specified for luarocks.
The patch also sorts variables in alphabetical order.

Needed for google/oss-fuzz#14610

Author: ligurio

CHANGELOG.md

@@ -24,6 +24,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Support OSS Fuzz environment (#73).
 - Support for building on Ubuntu 24.04 AArch64 (ARM64).
 - Support for building on macOS ARM64.
+- Add `ENABLE_LUAJIT`, `LUAJIT_FRIENDLY_MODE` and `OSS_FUZZ`
+  variables to the rockspec.
 
 ### Changed
 
@@ -34,6 +36,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   `consume_numbers()` instead `double`.
 - Method `oneof()` in FuzzedDataProvider returns an item's index
   as a second value.
+- Rename CMake option `LUA_LIBRARIES` to `CMAKE_LUA_LIBRARIES` and
+  `LUA_INCLUDE_DIR` to `CMAKE_LUA_INCLUDE_DIR`.
 
 ### Fixed
 

CMakeLists.txt

@@ -16,13 +16,13 @@ endif()
 set(CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 include(SetClangRTLib)
 
-if(LUA_INCLUDE_DIR AND LUA_LIBRARIES)
+if(CMAKE_LUA_INCLUDE_DIR AND CMAKE_LUA_LIBRARIES)
   # When a path to a Lua library is passed outside, we should
   # mimic a real CMake library to don't break code that depends on
   # LUA_LIBRARIES.
   add_library(liblua STATIC IMPORTED GLOBAL)
   set_target_properties(liblua PROPERTIES
-    IMPORTED_LOCATION ${LUA_LIBRARIES})
+    IMPORTED_LOCATION ${CMAKE_LUA_LIBRARIES})
   set(LUA_LIBRARIES liblua)
   set(LUA_FOUND TRUE)
 elseif(ENABLE_LUAJIT)

luzer-scm-1.rockspec

@@ -26,10 +26,13 @@ build = {
     -- https://github.com/luarocks/luarocks/blob/7ed653f010671b3a7245be9adcc70068c049ef68/docs/config_file_format.md#config-file-format
     -- luacheck: pop
     variables = {
-        CMAKE_LUADIR = "$(LUADIR)",
-        CMAKE_LIBDIR = "$(LIBDIR)",
         CMAKE_BUILD_TYPE = "RelWithDebInfo",
         CMAKE_C_COMPILER = "clang",
         CMAKE_CXX_COMPILER = "clang++",
+        CMAKE_LIBDIR = "$(LIBDIR)",
+        CMAKE_LUADIR = "$(LUADIR)",
+        ENABLE_LUAJIT = "$(ENABLE_LUAJIT)",
+        LUAJIT_FRIENDLY_MODE = "$(LUAJIT_FRIENDLY_MODE)",
+        OSS_FUZZ = "$(OSS_FUZZ)",
     },
 }