pycapicompat.h: Initial stub - lots of TODO for @Daetalus

README.rst

+========================================================================================================
+ pycapicompat.h - Extra CAPI functions for compatibility between various C-based Python implementations
+========================================================================================================
+
+`pycapicompat.h` is a C-header with additional CAPI functions providing unified
+access to C-based functionality between various C-bases Python implementations.
+Currently covered are:
+
+- Pyston_
+- CPython_
+
+we would also be glad to cover PyPy_ and we will try to do so on a best effort basis.
+Patches are, as always, welcome.
+
+
+.. _Pyston:     https://pyston.org/
+.. _CPython:    https://www.python.org/
+.. _PyPy:       http://pypy.org/

pycapicompat.h

+#ifndef _PYCAPICOMPAT_H_
+#define _PYCAPICOMPAT_H_
+
+/* pycapicompat.h - Extra CAPI functions for compatibility between various C-based Python implementations
+ * This file has been placed into Public Domain.
+ *
+ * The recommended way to use pycapicompat.h is to copy it from canonical
+ * location to your project on as-needed basis and include locally.
+ *
+ * The canonical location is:
+ *
+ *   https://lab.nexedi.com/nexedi/pycapicompat/raw/master/pycapicompat.h
+ *   (or https://lab.nexedi.com/nexedi/pycapicompat.git for Git access)
+ *
+ * Last updated: 2016-06-13
+ */
+
+#include <Python.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// TODO(Daetalus)
+#if 0
+#ifndef IMPLEMENTATION_SUPPORTS_EXTENDED_C_API
+#define PyErr_GetExcInfoType() PyThreadState_GET()->exc_type
+#endif
+#ifdef PYSTON_VERSION
+  foo = PyErr_GetExcInfoType(); // a new API function
+#else
+  foo = PyThreadState_GET()->exc_type; // direct field access
+#endif
+#endif
+
+// info about free variables
+// TODO(Daetalus) verify and fill more
+#ifdef CPYTHON_VERSION
+// TODO(Daetalus) see how Cython does this check
+#elif defined(PYSTON_VERSION)
+void PyCode_HasFreeVars(BoxedCode* code) {
+  return code->source->getScopeInfo()->takesClosure();
+}
+#else
+# error TODO pypy:PyCode_HasFreeVars not implemented for your python version
+#endif
+
+// TODO(Daetalus) add more stuff.
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif