Make the C accelerator modules compatible with Python 3

This is just the first step toward full compatibility with Python 3: it
discloses some problems related to bytes-vs-str stricter rules that
needs to be sorted out.

dulwich/_diff_tree.c

@@ -32,6 +32,22 @@ typedef int Py_ssize_t;
 #define Py_SIZE(ob)             (((PyVarObject*)(ob))->ob_size)
 #endif
 
+#if PY_MAJOR_VERSION >= 3
+#define PyInt_FromLong PyLong_FromLong
+#define PyInt_AsLong PyLong_AsLong
+#define PyInt_AS_LONG PyLong_AS_LONG
+#define PyString_AS_STRING PyBytes_AS_STRING
+#define PyString_AsString PyBytes_AsString
+#define PyString_AsStringAndSize PyBytes_AsStringAndSize
+#define PyString_Check PyBytes_Check
+#define PyString_CheckExact PyBytes_CheckExact
+#define PyString_FromStringAndSize PyBytes_FromStringAndSize
+#define PyString_FromString PyBytes_FromString
+#define PyString_GET_SIZE PyBytes_GET_SIZE
+#define PyString_Size PyBytes_Size
+#define _PyString_Join _PyBytes_Join
+#endif
+
 static PyObject *tree_entry_cls = NULL, *null_entry = NULL,
 	*defaultdict_cls = NULL, *int_cls = NULL;
 static int block_size;
@@ -152,6 +168,17 @@ static int entry_path_cmp(PyObject *entry1, PyObject *entry2)
 	path1 = PyObject_GetAttrString(entry1, "path");
 	if (!path1)
 		goto done;
+
+#if PY_MAJOR_VERSION >= 3
+	/* XXX: Is FSConverter desiderable here? */
+	if (PyUnicode_Check(path1)) {
+		PyObject *bytes;
+		if (!PyUnicode_FSConverter(path1, &bytes))
+			goto done;
+		Py_DECREF(path1);
+		path1 = bytes;
+	}
+#endif
 	if (!PyString_Check(path1)) {
 		PyErr_SetString(PyExc_TypeError, "path is not a string");
 		goto done;
@@ -160,6 +187,17 @@ static int entry_path_cmp(PyObject *entry1, PyObject *entry2)
 	path2 = PyObject_GetAttrString(entry2, "path");
 	if (!path2)
 		goto done;
+
+#if PY_MAJOR_VERSION >= 3
+	/* XXX: Is FSConverter desiderable here? */
+	if (PyUnicode_Check(path2)) {
+		PyObject *bytes;
+		if (!PyUnicode_FSConverter(path2, &bytes))
+			goto done;
+		Py_DECREF(path2);
+		path2 = bytes;
+	}
+#endif
 	if (!PyString_Check(path2)) {
 		PyErr_SetString(PyExc_TypeError, "path is not a string");
 		goto done;
@@ -390,12 +428,28 @@ static PyMethodDef py_diff_tree_methods[] = {
 	{ NULL, NULL, 0, NULL }
 };
 
-PyMODINIT_FUNC
-init_diff_tree(void)
+static PyObject *
+moduleinit(void)
 {
 	PyObject *m, *objects_mod = NULL, *diff_tree_mod = NULL;
-        PyObject *block_size_obj = NULL;
+	PyObject *block_size_obj = NULL;
+
+#if PY_MAJOR_VERSION >= 3
+	static struct PyModuleDef moduledef = {
+		PyModuleDef_HEAD_INIT,
+		"_diff_tree",         /* m_name */
+		NULL,                 /* m_doc */
+		-1,                   /* m_size */
+		py_diff_tree_methods, /* m_methods */
+		NULL,                 /* m_reload */
+		NULL,                 /* m_traverse */
+		NULL,                 /* m_clear*/
+		NULL,                 /* m_free */
+	};
+	m = PyModule_Create(&moduledef);
+#else
 	m = Py_InitModule("_diff_tree", py_diff_tree_methods);
+#endif
 	if (!m)
 		goto error;
 
@@ -437,11 +491,8 @@ init_diff_tree(void)
 	}
 
 	Py_DECREF(diff_tree_mod);
-#if PY_MAJOR_VERSION < 3
-	return;
-#else
-	return NULL;
-#endif
+
+	return m;
 
 error:
 	Py_XDECREF(objects_mod);
@@ -450,9 +501,19 @@ error:
 	Py_XDECREF(block_size_obj);
 	Py_XDECREF(defaultdict_cls);
 	Py_XDECREF(int_cls);
-#if PY_MAJOR_VERSION < 3
-	return;
-#else
 	return NULL;
-#endif
 }
+
+#if PY_MAJOR_VERSION >= 3
+PyMODINIT_FUNC
+PyInit__diff_tree(void)
+{
+	return moduleinit();
+}
+#else
+PyMODINIT_FUNC
+init_diff_tree(void)
+{
+	moduleinit();
+}
+#endif

dulwich/_objects.c

@@ -25,6 +25,15 @@
 typedef int Py_ssize_t;
 #endif
 
+#if PY_MAJOR_VERSION >= 3
+#define PyInt_Check(obj) 0
+#define PyInt_CheckExact(obj) 0
+#define PyInt_AsLong PyLong_AsLong
+#define PyString_AS_STRING PyBytes_AS_STRING
+#define PyString_Check PyBytes_Check
+#define PyString_FromStringAndSize PyBytes_FromStringAndSize
+#endif
+
 #if defined(__MINGW32_VERSION) || defined(__APPLE__)
 size_t rep_strnlen(char *text, size_t maxlen);
 size_t rep_strnlen(char *text, size_t maxlen)
@@ -248,58 +257,69 @@ static PyMethodDef py_objects_methods[] = {
 	{ NULL, NULL, 0, NULL }
 };
 
-PyMODINIT_FUNC
-init_objects(void)
+static PyObject *
+moduleinit(void)
 {
 	PyObject *m, *objects_mod, *errors_mod;
 
-	m = Py_InitModule3("_objects", py_objects_methods, NULL);
-	if (m == NULL) {
-#if PY_MAJOR_VERSION < 3
-	  return;
+#if PY_MAJOR_VERSION >= 3
+	static struct PyModuleDef moduledef = {
+		PyModuleDef_HEAD_INIT,
+		"_objects",         /* m_name */
+		NULL,               /* m_doc */
+		-1,                 /* m_size */
+		py_objects_methods, /* m_methods */
+		NULL,               /* m_reload */
+		NULL,               /* m_traverse */
+		NULL,               /* m_clear*/
+		NULL,               /* m_free */
+	};
+	m = PyModule_Create(&moduledef);
 #else
-	  return NULL;
+	m = Py_InitModule3("_objects", py_objects_methods, NULL);
 #endif
+	if (m == NULL) {
+		return NULL;
 	}
 
 	errors_mod = PyImport_ImportModule("dulwich.errors");
 	if (errors_mod == NULL) {
-#if PY_MAJOR_VERSION < 3
-	  return;
-#else
-	  return NULL;
-#endif
+		return NULL;
 	}
 
 	object_format_exception_cls = PyObject_GetAttrString(
 		errors_mod, "ObjectFormatException");
 	Py_DECREF(errors_mod);
 	if (object_format_exception_cls == NULL) {
-#if PY_MAJOR_VERSION < 3
-	  return;
-#else
-	  return NULL;
-#endif
+		return NULL;
 	}
 
 	/* This is a circular import but should be safe since this module is
 	 * imported at at the very bottom of objects.py. */
 	objects_mod = PyImport_ImportModule("dulwich.objects");
 	if (objects_mod == NULL) {
-#if PY_MAJOR_VERSION < 3
-	  return;
-#else
-	  return NULL;
-#endif
+		return NULL;
 	}
 
 	tree_entry_cls = PyObject_GetAttrString(objects_mod, "TreeEntry");
 	Py_DECREF(objects_mod);
 	if (tree_entry_cls == NULL) {
-#if PY_MAJOR_VERSION < 3
-	  return;
-#else
-	  return NULL;
-#endif
+		return NULL;
 	}
+
+	return m;
+}
+
+#if PY_MAJOR_VERSION >= 3
+PyMODINIT_FUNC
+PyInit__objects(void)
+{
+	return moduleinit();
+}
+#else
+PyMODINIT_FUNC
+init_objects(void)
+{
+	moduleinit();
 }
+#endif

dulwich/_pack.c

@@ -20,6 +20,19 @@
 #include <Python.h>
 #include <stdint.h>
 
+#if PY_MAJOR_VERSION >= 3
+#define PyInt_FromLong PyLong_FromLong
+#define PyString_AS_STRING PyBytes_AS_STRING
+#define PyString_AsString PyBytes_AsString
+#define PyString_Check PyBytes_Check
+#define PyString_CheckExact PyBytes_CheckExact
+#define PyString_FromStringAndSize PyBytes_FromStringAndSize
+#define PyString_FromString PyBytes_FromString
+#define PyString_GET_SIZE PyBytes_GET_SIZE
+#define PyString_Size PyBytes_Size
+#define _PyString_Join _PyBytes_Join
+#endif
+
 static PyObject *PyExc_ApplyDeltaError = NULL;
 
 static int py_is_sha(PyObject *sha)
@@ -239,21 +252,53 @@ static PyMethodDef py_pack_methods[] = {
 	{ NULL, NULL, 0, NULL }
 };
 
-void init_pack(void)
+static PyObject *
+moduleinit(void)
 {
 	PyObject *m;
 	PyObject *errors_module;
 
 	errors_module = PyImport_ImportModule("dulwich.errors");
 	if (errors_module == NULL)
-		return;
+		return NULL;
 
 	PyExc_ApplyDeltaError = PyObject_GetAttrString(errors_module, "ApplyDeltaError");
 	Py_DECREF(errors_module);
 	if (PyExc_ApplyDeltaError == NULL)
-		return;
+		return NULL;
 
+#if PY_MAJOR_VERSION >= 3
+	static struct PyModuleDef moduledef = {
+	  PyModuleDef_HEAD_INIT,
+	  "_pack",         /* m_name */
+	  NULL,            /* m_doc */
+	  -1,              /* m_size */
+	  py_pack_methods, /* m_methods */
+	  NULL,            /* m_reload */
+	  NULL,            /* m_traverse */
+	  NULL,            /* m_clear*/
+	  NULL,            /* m_free */
+	};
+	m = PyModule_Create(&moduledef);
+#else
 	m = Py_InitModule3("_pack", py_pack_methods, NULL);
+#endif
 	if (m == NULL)
-		return;
+		return NULL;
+
+	return m;
+}
+
+#if PY_MAJOR_VERSION >= 3
+PyMODINIT_FUNC
+PyInit__pack(void)
+{
+	return moduleinit();
+}
+#else
+PyMODINIT_FUNC
+init_pack(void)
+{
+	moduleinit();
 }
+#endif