Skip to content

Commit aefa7eb

Browse files
serhiy-storchakavstinner
authored andcommitted
bpo-6532: Make the thread id an unsigned integer. (#781)
* bpo-6532: Make the thread id an unsigned integer. From C API side the type of results of PyThread_start_new_thread() and PyThread_get_thread_ident(), the id parameter of PyThreadState_SetAsyncExc(), and the thread_id field of PyThreadState changed from "long" to "unsigned long". * Restore a check in thread_get_ident().
1 parent 1e2147b commit aefa7eb

27 files changed

+116
-88
lines changed

Doc/c-api/init.rst

Lines changed: 4 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -830,7 +830,7 @@ been created.
830830
the caller should assume no current thread state is available.
831831
832832
833-
.. c:function:: int PyThreadState_SetAsyncExc(long id, PyObject *exc)
833+
.. c:function:: int PyThreadState_SetAsyncExc(unsigned long id, PyObject *exc)
834834
835835
Asynchronously raise an exception in a thread. The *id* argument is the thread
836836
id of the target thread; *exc* is the exception object to be raised. This
@@ -840,6 +840,9 @@ been created.
840840
zero if the thread id isn't found. If *exc* is :const:`NULL`, the pending
841841
exception (if any) for the thread is cleared. This raises no exceptions.
842842
843+
.. versionchanged:: 3.7
844+
The type of the *id* parameter changed from :c:type:`long` to
845+
:c:type:`unsigned long`.
843846
844847
.. c:function:: void PyEval_AcquireThread(PyThreadState *tstate)
845848

Doc/whatsnew/3.7.rst

Lines changed: 10 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -185,6 +185,16 @@ Deprecated
185185
(Contributed by Serhiy Storchaka in :issue:`28692`.)
186186

187187

188+
Changes in the C API
189+
--------------------
190+
191+
- The type of results of :c:func:`PyThread_start_new_thread` and
192+
:c:func:`PyThread_get_thread_ident`, and the *id* parameter of
193+
:c:func:`PyThreadState_SetAsyncExc` changed from :c:type:`long` to
194+
:c:type:`unsigned long`.
195+
(Contributed by Serhiy Storchaka in :issue:`6532`.)
196+
197+
188198
Removed
189199
=======
190200

Include/pystate.h

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -108,7 +108,7 @@ typedef struct _ts {
108108
int gilstate_counter;
109109

110110
PyObject *async_exc; /* Asynchronous exception to raise */
111-
long thread_id; /* Thread id where this tstate was created */
111+
unsigned long thread_id; /* Thread id where this tstate was created */
112112

113113
int trash_delete_nesting;
114114
PyObject *trash_delete_later;
@@ -200,7 +200,7 @@ PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
200200

201201
PyAPI_FUNC(PyThreadState *) PyThreadState_Swap(PyThreadState *);
202202
PyAPI_FUNC(PyObject *) PyThreadState_GetDict(void);
203-
PyAPI_FUNC(int) PyThreadState_SetAsyncExc(long, PyObject *);
203+
PyAPI_FUNC(int) PyThreadState_SetAsyncExc(unsigned long, PyObject *);
204204

205205

206206
/* Variable and macro for in-line access to current thread state */

Include/pythread.h

Lines changed: 6 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -17,10 +17,14 @@ typedef enum PyLockStatus {
1717
PY_LOCK_INTR
1818
} PyLockStatus;
1919

20+
#ifndef Py_LIMITED_API
21+
#define PYTHREAD_INVALID_THREAD_ID ((unsigned long)-1)
22+
#endif
23+
2024
PyAPI_FUNC(void) PyThread_init_thread(void);
21-
PyAPI_FUNC(long) PyThread_start_new_thread(void (*)(void *), void *);
25+
PyAPI_FUNC(unsigned long) PyThread_start_new_thread(void (*)(void *), void *);
2226
PyAPI_FUNC(void) PyThread_exit_thread(void);
23-
PyAPI_FUNC(long) PyThread_get_thread_ident(void);
27+
PyAPI_FUNC(unsigned long) PyThread_get_thread_ident(void);
2428

2529
PyAPI_FUNC(PyThread_type_lock) PyThread_allocate_lock(void);
2630
PyAPI_FUNC(void) PyThread_free_lock(PyThread_type_lock);

Lib/_dummy_thread.py

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -69,7 +69,7 @@ def get_ident():
6969
available, it is safe to assume that the current process is the
7070
only thread. Thus a constant can be safely returned.
7171
"""
72-
return -1
72+
return 1
7373

7474
def allocate_lock():
7575
"""Dummy implementation of _thread.allocate_lock()."""

Lib/test/test_dummy_thread.py

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -111,8 +111,7 @@ def test_exit(self):
111111
def test_ident(self):
112112
self.assertIsInstance(_thread.get_ident(), int,
113113
"_thread.get_ident() returned a non-integer")
114-
self.assertNotEqual(_thread.get_ident(), 0,
115-
"_thread.get_ident() returned 0")
114+
self.assertGreater(_thread.get_ident(), 0)
116115

117116
def test_LockType(self):
118117
self.assertIsInstance(_thread.allocate_lock(), _thread.LockType,

Lib/test/test_sys.py

Lines changed: 3 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -393,6 +393,9 @@ def g456():
393393
thread_id = thread_info[0]
394394

395395
d = sys._current_frames()
396+
for tid in d:
397+
self.assertIsInstance(tid, int)
398+
self.assertGreater(tid, 0)
396399

397400
main_id = threading.get_ident()
398401
self.assertIn(main_id, d)

Lib/test/test_threading.py

Lines changed: 6 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -181,6 +181,7 @@ def test_PyThreadState_SetAsyncExc(self):
181181
ctypes = import_module("ctypes")
182182

183183
set_async_exc = ctypes.pythonapi.PyThreadState_SetAsyncExc
184+
set_async_exc.argtypes = (ctypes.c_ulong, ctypes.py_object)
184185

185186
class AsyncExc(Exception):
186187
pass
@@ -189,9 +190,11 @@ class AsyncExc(Exception):
189190

190191
# First check it works when setting the exception from the same thread.
191192
tid = threading.get_ident()
193+
self.assertIsInstance(tid, int)
194+
self.assertGreater(tid, 0)
192195

193196
try:
194-
result = set_async_exc(ctypes.c_long(tid), exception)
197+
result = set_async_exc(tid, exception)
195198
# The exception is async, so we might have to keep the VM busy until
196199
# it notices.
197200
while True:
@@ -237,7 +240,7 @@ def run(self):
237240
# Try a thread id that doesn't make sense.
238241
if verbose:
239242
print(" trying nonsensical thread id")
240-
result = set_async_exc(ctypes.c_long(-1), exception)
243+
result = set_async_exc(-1, exception)
241244
self.assertEqual(result, 0) # no thread states modified
242245

243246
# Now raise an exception in the worker thread.
@@ -250,7 +253,7 @@ def run(self):
250253
self.assertFalse(t.finished)
251254
if verbose:
252255
print(" attempting to raise asynch exception in worker")
253-
result = set_async_exc(ctypes.c_long(t.id), exception)
256+
result = set_async_exc(t.id, exception)
254257
self.assertEqual(result, 1) # one thread state modified
255258
if verbose:
256259
print(" waiting for worker to say it caught the exception")

Lib/threading.py

Lines changed: 2 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -993,14 +993,14 @@ def _delete(self):
993993
#
994994
# Must take care to not raise an exception if _dummy_thread is being
995995
# used (and thus this module is being used as an instance of
996-
# dummy_threading). _dummy_thread.get_ident() always returns -1 since
996+
# dummy_threading). _dummy_thread.get_ident() always returns 1 since
997997
# there is only one thread if _dummy_thread is being used. Thus
998998
# len(_active) is always <= 1 here, and any Thread instance created
999999
# overwrites the (if any) thread currently registered in _active.
10001000
#
10011001
# An instance of _MainThread is always created by 'threading'. This
10021002
# gets overwritten the instant an instance of Thread is created; both
1003-
# threads return -1 from _dummy_thread.get_ident() and thus have the
1003+
# threads return 1 from _dummy_thread.get_ident() and thus have the
10041004
# same key in the dict. So when the _MainThread instance created by
10051005
# 'threading' tries to clean itself up when atexit calls this method
10061006
# it gets a KeyError if another Thread instance was created.

Misc/NEWS

Lines changed: 4 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -813,6 +813,10 @@ Windows
813813
C API
814814
-----
815815

816+
- bpo-6532: The type of results of PyThread_start_new_thread() and
817+
PyThread_get_thread_ident(), and the id parameter of
818+
PyThreadState_SetAsyncExc() changed from "long" to "unsigned long".
819+
816820
- Issue #27867: Function PySlice_GetIndicesEx() is deprecated and replaced with
817821
a macro if Py_LIMITED_API is not set or set to the value between 0x03050400
818822
and 0x03060000 (not including) or 0x03060100 or higher. Added functions

0 commit comments

Comments
 (0)