New PyGILState_ API - implements pep 311, from patch 684256.

2 files changed, 53 insertions, 50 deletions

diff --git a/Modules/_testcapimodule.c b/Modules/_testcapimodule.c
index b3da398..b52e965 100644
--- a/Modules/_testcapimodule.c
+++ b/Modules/_testcapimodule.c
@@ -7,6 +7,10 @@
 
 #include "Python.h"
 
+#ifdef WITH_THREAD
+#include "pythread.h"
+#endif /* WITH_THREAD */
+
 static PyObject *TestError;	/* set to exception object in init */
 
 /* Raise TestError with test_name + ": " + msg, and return NULL. */
@@ -535,6 +539,46 @@ raise_exception(PyObject *self, PyObject *args)
 	return NULL;
 }
 
+#ifdef WITH_THREAD
+
+void _make_call(void *callable)
+{
+	PyObject *rc;
+	PyGILState_STATE s = PyGILState_Ensure();
+	rc = PyObject_CallFunction(callable, "");
+	Py_XDECREF(rc);
+	PyGILState_Release(s);
+}
+
+static PyObject *
+test_thread_state(PyObject *self, PyObject *args)
+{
+	PyObject *fn;
+	if (!PyArg_ParseTuple(args, "O:test_thread_state", &fn))
+		return NULL;
+	/* Ensure Python is setup for threading */
+	PyEval_InitThreads();
+	/* Start a new thread for our callback. */
+	PyThread_start_new_thread( _make_call, fn);
+	/* Make the callback with the thread lock held by this thread */
+	_make_call(fn);
+	/* Do it all again, but this time with the thread-lock released */
+	Py_BEGIN_ALLOW_THREADS
+	_make_call(fn);
+	Py_END_ALLOW_THREADS
+	/* And once more with and without a thread
+	   XXX - should use a lock and work out exactly what we are trying 
+	   to test <wink> 
+	*/
+	Py_BEGIN_ALLOW_THREADS
+	PyThread_start_new_thread( _make_call, fn);
+	_make_call(fn);
+	Py_END_ALLOW_THREADS
+	Py_INCREF(Py_None);
+	return Py_None;
+}
+#endif
+
 static PyMethodDef TestMethods[] = {
 	{"raise_exception",	raise_exception,		 METH_VARARGS},
 	{"test_config",		(PyCFunction)test_config,	 METH_NOARGS},
@@ -554,6 +598,9 @@ static PyMethodDef TestMethods[] = {
 #ifdef Py_USING_UNICODE
 	{"test_u_code",		(PyCFunction)test_u_code,	 METH_NOARGS},
 #endif
+#ifdef WITH_THREAD
+	{"_test_thread_state", (PyCFunction)test_thread_state, METH_VARARGS},
+#endif
 	{NULL, NULL} /* sentinel */
 };
 
diff --git a/Modules/posixmodule.c b/Modules/posixmodule.c
index 9bf52f3..d34756a 100644
--- a/Modules/posixmodule.c
+++ b/Modules/posixmodule.c
@@ -4354,22 +4354,11 @@ _PyPopen(char *cmdstring, int mode, int n)
  * exit code as the result of the close() operation.  This permits the
  * files to be closed in any order - it is always the close() of the
  * final handle that will return the exit code.
+ *
+ * NOTE: This function is currently called with the GIL released.
+ * hence we use the GILState API to manage our state.
  */
 
- /* RED_FLAG 31-Aug-2000 Tim
-  * This is always called (today!) between a pair of
-  * Py_BEGIN_ALLOW_THREADS/ Py_END_ALLOW_THREADS
-  * macros.  So the thread running this has no valid thread state, as
-  * far as Python is concerned.  However, this calls some Python API
-  * functions that cannot be called safely without a valid thread
-  * state, in particular PyDict_GetItem.
-  * As a temporary hack (although it may last for years ...), we
-  * *rely* on not having a valid thread state in this function, in
-  * order to create our own "from scratch".
-  * This will deadlock if _PyPclose is ever called by a thread
-  * holding the global lock.
-  */
-
 static int _PyPclose(FILE *file)
 {
 	int result;
@@ -4378,40 +4367,16 @@ static int _PyPclose(FILE *file)
 	PyObject *procObj, *hProcessObj, *intObj, *fileObj;
 	long file_count;
 #ifdef WITH_THREAD
-	PyInterpreterState* pInterpreterState;
-	PyThreadState* pThreadState;
+	PyGILState_STATE state;
 #endif
 
 	/* Close the file handle first, to ensure it can't block the
 	 * child from exiting if it's the last handle.
 	 */
 	result = fclose(file);
-
 #ifdef WITH_THREAD
-	/* Bootstrap a valid thread state into existence. */
-	pInterpreterState = PyInterpreterState_New();
-	if (!pInterpreterState) {
-		/* Well, we're hosed now!  We don't have a thread
-		 * state, so can't call a nice error routine, or raise
-		 * an exception.  Just die.
-		 */
-		 Py_FatalError("unable to allocate interpreter state "
-		 	       "when closing popen object");
-		 return -1;  /* unreachable */
-	}
-	pThreadState = PyThreadState_New(pInterpreterState);
-	if (!pThreadState) {
-		 Py_FatalError("unable to allocate thread state "
-		 	       "when closing popen object");
-		 return -1;  /* unreachable */
-	}
-	/* Grab the global lock.  Note that this will deadlock if the
-	 * current thread already has the lock! (see RED_FLAG comments
-	 * before this function)
-	 */
-	PyEval_RestoreThread(pThreadState);
+	state = PyGILState_Ensure();
 #endif
-
 	if (_PyPopenProcs) {
 		if ((fileObj = PyLong_FromVoidPtr(file)) != NULL &&
 		    (procObj = PyDict_GetItem(_PyPopenProcs,
@@ -4470,17 +4435,8 @@ static int _PyPclose(FILE *file)
 	} /* if _PyPopenProcs */
 
 #ifdef WITH_THREAD
-	/* Tear down the thread & interpreter states.
-	 * Note that interpreter state clear & delete functions automatically
-	 * call the thread clear & delete functions, and indeed insist on
-	 * doing that themselves.  The lock must be held during the clear, but
-	 * need not be held during the delete.
-	 */
-	PyInterpreterState_Clear(pInterpreterState);
-	PyEval_ReleaseThread(pThreadState);
-	PyInterpreterState_Delete(pInterpreterState);
+	PyGILState_Release(state);
 #endif
-
 	return result;
 }