From: Antoine Pitrou <solipsis@pitrou.net>
Date: Wed, 9 Nov 2011 23:33:50 +0000 (+0100)
Subject: Issue #13373: multiprocessing.Queue.get() could sometimes block indefinitely
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6a570d6b9af07a03859dd2175086e45ab60f4ee9;p=python

Issue #13373: multiprocessing.Queue.get() could sometimes block indefinitely
when called with a timeout.  Patch by Arnaud Ysmal.
---

diff --git a/Lib/multiprocessing/queues.py b/Lib/multiprocessing/queues.py
index b7eecefa20..433c7e29de 100644
--- a/Lib/multiprocessing/queues.py
+++ b/Lib/multiprocessing/queues.py
@@ -126,7 +126,11 @@ class Queue(object):
             if not self._rlock.acquire(block, timeout):
                 raise Empty
             try:
-                if not self._poll(block and (deadline-time.time()) or 0.0):
+                if block:
+                    timeout = deadline - time.time()
+                    if timeout < 0 or not self._poll(timeout):
+                        raise Empty
+                elif not self._poll():
                     raise Empty
                 res = self._recv()
                 self._sem.release()
diff --git a/Misc/ACKS b/Misc/ACKS
index 97c961cb12..e6d9865bff 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -924,6 +924,7 @@ Bob Yodlowski
 Danny Yoo
 George Yoshida
 Masazumi Yoshikawa
+Arnaud Ysmal
 Bernard Yue
 Moshe Zadka
 Milan Zamazal
diff --git a/Misc/NEWS b/Misc/NEWS
index 21fdbdce81..9517677ee2 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -76,6 +76,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #13373: multiprocessing.Queue.get() could sometimes block indefinitely
+  when called with a timeout.  Patch by Arnaud Ysmal.
+
 - Issue #3067: Enhance the documentation and docstring of
   locale.setlocale().