Add a test case for ctypes callback

source/tests/Makefile

@@ -26,7 +26,7 @@ BASE_FLAGS += -Wpointer-arith -Wabi -Winit-self -Wuninitialized -Wunused-paramet
 
 LINK_FLAGS =
 
-ifneq ($(CC),clang-3.4)
+ifneq ($(CC),clang)
 BASE_FLAGS += -Wlogical-op -Wunsafe-loop-optimizations
 endif
 
@@ -121,6 +121,12 @@ ansi-pedantic-test_cxxlang: ansi-pedantic-test.cpp ../backend/Carla*.h ../includ
 
 # --------------------------------------------------------------
 
+ctypes-test.so: ctypes-test.c .FORCED
+	$(CC) $< $(PEDANTIC_C_FLAGS) -shared -o $@
+	set -e; ./ctypes-test.py
+
+# --------------------------------------------------------------
+
 CachedPlugins: CachedPlugins.cpp
 	$(CXX) $< $(PEDANTIC_CXX_FLAGS) -o $@ $(MODULEDIR)/juce_core.a $(MODULEDIR)/lilv.a -ldl -lpthread
 ifneq ($(WIN32),true)
@@ -269,3 +275,5 @@ DGL: DGL.cpp ../modules/distrho/dgl/src/Window.cpp
 # 	valgrind ./DGL
 
 # --------------------------------------------------------------
+
+.PHONY: .FORCED

source/tests/ctypes-test.c

@@ -0,0 +1,23 @@
+#include <assert.h>
+#include <stdio.h>
+
+typedef void (*PythonSideFn)(int checker);
+
+PythonSideFn pyFn = NULL;
+
+__attribute__ ((visibility("default")))
+void set_python_side_fn(PythonSideFn fn)
+{
+    printf("set_python_side_fn(%p)\n", fn);
+    pyFn = fn;
+}
+
+__attribute__ ((visibility("default")))
+void call_python_side_fn(void)
+{
+    assert(pyFn != NULL);
+
+    printf("going to call python function now, ptr: %p\n", pyFn);
+    pyFn(1337);
+    printf("done!\n");
+}

source/tests/ctypes-test.py

@@ -0,0 +1,22 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+from ctypes import *
+
+PythonSideFn = CFUNCTYPE(None, c_int)
+
+lib = CDLL("./ctypes-test.so", RTLD_LOCAL)
+
+lib.set_python_side_fn.argtypes = [PythonSideFn]
+lib.set_python_side_fn.restype = None
+lib.call_python_side_fn.argtypes = None
+lib.call_python_side_fn.restype = None
+
+def pyFn(checker):
+    print("Python function called from C code, checker:", checker)
+
+_pyFn = PythonSideFn(pyFn)
+lib.set_python_side_fn(_pyFn)
+
+print("Python side ready, calling C function now")
+lib.call_python_side_fn()