Fix use of PyContext* APIs in 3.7.1

See https://bugs.python.org/issue34762 for details.

Author: 1st1

uvloop/cbhandles.pyx

@@ -15,11 +15,9 @@ cdef class Handle:
             self._source_traceback = extract_stack()
 
     cdef inline _set_context(self, object context):
-        cdef PyContext* current_context
-
         if PY37:
             if context is None:
-                context = copy_current_context()
+                context = Context_CopyCurrent()
             self.context = context
         else:
             if context is not None:
@@ -54,7 +52,7 @@ cdef class Handle:
         try:
             if PY37:
                 assert self.context is not None
-                PyContext_Enter(<PyContext*>self.context)
+                Context_Enter(self.context)
 
             if cb_type == 1:
                 callback = self.arg1
@@ -103,7 +101,7 @@ cdef class Handle:
             context = self.context
             Py_DECREF(self)
             if PY37:
-                PyContext_Exit(<PyContext*>context)
+                Context_Exit(context)
 
     cdef _cancel(self):
         self._cancelled = 1
@@ -181,7 +179,7 @@ cdef class TimerHandle:
 
         if PY37:
             if context is None:
-                context = copy_current_context()
+                context = Context_CopyCurrent()
             self.context = context
         else:
             if context is not None:
@@ -239,7 +237,7 @@ cdef class TimerHandle:
         try:
             if PY37:
                 assert self.context is not None
-                PyContext_Enter(<PyContext*>self.context)
+                Context_Enter(self.context)
 
             if args is not None:
                 callback(*args)
@@ -267,7 +265,7 @@ cdef class TimerHandle:
             context = self.context
             Py_DECREF(self)
             if PY37:
-                PyContext_Exit(<PyContext*>context)
+                Context_Exit(context)
 
     # Public API
 
@@ -402,15 +400,3 @@ cdef extract_stack():
 
     stack.reverse()
     return stack
-
-
-cdef copy_current_context():
-    cdef PyContext* current_context
-
-    if PY37:
-        current_context = PyContext_CopyCurrent()
-        py_context = <object>current_context
-        Py_XDECREF(<PyObject*>current_context)
-        return py_context
-
-    raise NotImplementedError('"contextvars" support requires Python 3.7+')

uvloop/includes/compat.h

@@ -31,24 +31,53 @@ int epoll_ctl(int epfd, int op, int fd, struct epoll_event *event) {};
 
 
 #if PY_VERSION_HEX < 0x03070000
-typedef struct {
-    PyObject_HEAD
-} PyContext;
 
-PyContext * PyContext_CopyCurrent(void) {
-    abort();
+PyObject * Context_CopyCurrent(void) {
+    PyErr_SetString(PyExc_NotImplementedError,
+                    '"contextvars" support requires Python 3.7+');
     return NULL;
 };
 
-int PyContext_Enter(PyContext *ctx) {
-    abort();
+int Context_Enter(PyObject *ctx) {
+    PyErr_SetString(PyExc_NotImplementedError,
+                    '"contextvars" support requires Python 3.7+');
     return -1;
 }
 
-int PyContext_Exit(PyContext *ctx) {
-    abort();
+int Context_Exit(PyObject *ctx) {
+    PyErr_SetString(PyExc_NotImplementedError,
+                    '"contextvars" support requires Python 3.7+');
     return -1;
 }
+
+#elif PY_VERSION_HEX < 0x03070100
+
+PyObject * Context_CopyCurrent(void) {
+    return (PyObject *)PyContext_CopyCurrent();
+};
+
+int Context_Enter(PyObject *ctx) {
+    return PyContext_Enter((PyContext *)ctx);
+}
+
+int Context_Exit(PyObject *ctx) {
+    return PyContext_Exit((PyContext *)ctx);
+}
+
+#else
+
+PyObject * Context_CopyCurrent(void) {
+    return PyContext_CopyCurrent();
+};
+
+int Context_Enter(PyObject *ctx) {
+    return PyContext_Enter(ctx);
+}
+
+int Context_Exit(PyObject *ctx) {
+    return PyContext_Exit(ctx);
+}
+
 #endif
 
 

uvloop/includes/python.pxd

@@ -18,6 +18,10 @@ cdef extern from "includes/compat.h":
     int PyContext_Enter(PyContext *) except -1
     int PyContext_Exit(PyContext *) except -1
 
+    object Context_CopyCurrent()
+    int Context_Enter(object) except -1
+    int Context_Exit(object) except -1
+
     void PyOS_BeforeFork()
     void PyOS_AfterFork_Parent()
     void PyOS_AfterFork_Child()

uvloop/loop.pyx

@@ -12,10 +12,9 @@ from .includes.python cimport PY_VERSION_HEX, \
                               PyUnicode_EncodeFSDefault, \
                               PyErr_SetInterrupt, \
                               _Py_RestoreSignals, \
-                              PyContext, \
-                              PyContext_CopyCurrent, \
-                              PyContext_Enter, \
-                              PyContext_Exit, \
+                              Context_CopyCurrent, \
+                              Context_Enter, \
+                              Context_Exit, \
                               PyOS_AfterFork_Parent, PyOS_AfterFork_Child, \
                               PyOS_BeforeFork