move helper annotations to helpers module

pythonbpf/helper/__init__.py

@@ -1,4 +1,13 @@
 from .helper_utils import HelperHandlerRegistry
 from .bpf_helper_handler import handle_helper_call
+from .helpers import ktime, pid, deref, XDP_DROP, XDP_PASS
 
-__all__ = ["HelperHandlerRegistry", "handle_helper_call"]
+__all__ = [
+    "HelperHandlerRegistry",
+    "handle_helper_call",
+    "ktime",
+    "pid",
+    "deref",
+    "XDP_DROP",
+    "XDP_PASS",
+]

pythonbpf/helper/helpers.py

@@ -0,0 +1,19 @@
+import ctypes
+
+
+def ktime():
+    return ctypes.c_int64(0)
+
+
+def pid():
+    return ctypes.c_int32(0)
+
+
+def deref(ptr):
+    "dereference a pointer"
+    result = ctypes.cast(ptr, ctypes.POINTER(ctypes.c_void_p)).contents.value
+    return result if result is not None else 0
+
+
+XDP_DROP = ctypes.c_int64(1)
+XDP_PASS = ctypes.c_int64(2)