[lua] Add cffi module

.gitmodules

@@ -81,3 +81,9 @@
 [submodule "third_party/tinyxml2"]
 	path = third_party/tinyxml2
 	url = https://github.com/aseprite/tinyxml2.git
+[submodule "third_party/libffi"]
+	path = third_party/libffi
+	url = https://github.com/lampysprites/libffi.git
+[submodule "third_party/cffi-lua"]
+	path = third_party/cffi-lua
+	url = https://github.com/lampysprites/cffi-lua.git

CMakeLists.txt

@@ -53,6 +53,7 @@ option(ENABLE_NEWS         "Enable the news in Home tab" on)
 option(ENABLE_UPDATER      "Enable automatic check for updates" on)
 option(ENABLE_SCRIPTING    "Compile with scripting support" on)
 option(ENABLE_WEBSOCKET    "Compile with websocket support" on)
+option(ENABLE_FFI          "Compile with FFI scripting support" on)
 option(ENABLE_TESTS        "Compile unit tests" off)
 option(ENABLE_BENCHMARKS   "Compile benchmarks" off)
 option(ENABLE_TRIAL_MODE   "Compile the trial version" off)

src/CMakeLists.txt

@@ -87,6 +87,10 @@ if(ENABLE_WEBSOCKET)
   add_definitions(-DENABLE_WEBSOCKET)
 endif()
 
+if(ENABLE_FFI)
+  add_definitions(-DENABLE_FFI)
+endif()
+
 ######################################################################
 # Aseprite Libraries (in preferred order to be built)
 

src/app/CMakeLists.txt

@@ -753,6 +753,10 @@ if(ENABLE_SCRIPTING)
   if(ENABLE_WEBSOCKET)
     target_link_libraries(app-lib ixwebsocket)
   endif()
+
+  if(ENABLE_FFI)
+    target_link_libraries(app-lib luacffi)
+  endif()
 endif()
 
 if(ENABLE_UPDATER)

src/app/script/engine.cpp

@@ -36,6 +36,10 @@
 #include "ui/base.h"
 #include "ui/cursor_type.h"
 #include "ui/mouse_button.h"
+#if ENABLE_FFI
+#include <lua.hh>
+#include <ffi.h>
+#endif
 
 #include <fstream>
 #include <sstream>
@@ -519,6 +523,14 @@ Engine::Engine()
   register_websocket_class(L);
 #endif
 
+  // Register FFI module
+#if ENABLE_FFI
+  ffi_module_open(L);
+  lua_pushvalue(L, -1);
+  lua_setglobal(L, "ffi");
+  lua_pop(L, 1);
+#endif
+
   // Check that we have a clean start (without dirty in the stack)
   ASSERT(lua_gettop(L) == top);
 }

third_party/CMakeLists.txt

@@ -231,6 +231,22 @@ if(ENABLE_SCRIPTING)
     add_subdirectory(IXWebSocket)
     target_include_directories(ixwebsocket PUBLIC)
   endif()
+
+  if(ENABLE_FFI)
+    add_subdirectory(libffi)
+    # main.cc is not required
+    add_library(luacffi
+      cffi-lua/src/util.cc
+      cffi-lua/src/ffilib.cc
+      cffi-lua/src/parser.cc
+      cffi-lua/src/ast.cc
+      cffi-lua/src/lib.cc
+      cffi-lua/src/ffi.cc
+    )
+    target_compile_definitions(luacffi PUBLIC FFI_LITTLE_ENDIAN)
+    target_include_directories(luacffi PUBLIC cffi-lua/src libffi/include ${CMAKE_CURRENT_BINARY_DIR}/libffi/include/)
+    target_link_libraries(luacffi lua lualib lauxlib ffi_static)
+  endif()
 
 endif()