[Python-checkins] cpython (3.1): Issue #11768: The signal handler of the signal module only calls

Mon Apr 18 16:30:25 CEST 2011

http://hg.python.org/cpython/rev/319f7af9ee5e
changeset: 69423:319f7af9ee5e
branch: 3.1
parent: 69418:6e090d78857c
user: Victor Stinner <victor.stinner at haypocalc.com>
date: Mon Apr 18 16:25:56 2011 +0200
summary:
 Issue #11768: The signal handler of the signal module only calls
Py_AddPendingCall() for the first signal to fix a deadlock on reentrant or
parallel calls. PyErr_SetInterrupt() writes also into the wake up file.
files:
 Misc/NEWS | 4 ++++
 Modules/signalmodule.c | 26 ++++++++++++++++----------
 2 files changed, 20 insertions(+), 10 deletions(-)

diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -55,6 +55,10 @@
 Library
 -------
 
+- Issue #11768: The signal handler of the signal module only calls
+ Py_AddPendingCall() for the first signal to fix a deadlock on reentrant or
+ parallel calls. PyErr_SetInterrupt() writes also into the wake up file.
+
 - Issue #11467: Fix urlparse behavior when handling urls which contains scheme
 specific part only digits. Patch by Santoso Wijaya.
 
diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -164,6 +164,20 @@
 }
 
 static void
+trip_signal(int sig_num)
+{
+ Handlers[sig_num].tripped = 1;
+ if (is_tripped)
+ return;
+ /* Set is_tripped after setting .tripped, as it gets
+ cleared in PyErr_CheckSignals() before .tripped. */
+ is_tripped = 1;
+ Py_AddPendingCall(checksignals_witharg, NULL);
+ if (wakeup_fd != -1)
+ write(wakeup_fd, "0円", 1);
+}
+
+static void
 signal_handler(int sig_num)
 {
 int save_errno = errno;
@@ -180,13 +194,7 @@
 if (getpid() == main_pid)
 #endif
 {
- Handlers[sig_num].tripped = 1;
- /* Set is_tripped after setting .tripped, as it gets
- cleared in PyErr_CheckSignals() before .tripped. */
- is_tripped = 1;
- Py_AddPendingCall(checksignals_witharg, NULL);
- if (wakeup_fd != -1)
- write(wakeup_fd, "0円", 1);
+ trip_signal(sig_num);
 }
 
 #ifndef HAVE_SIGACTION
@@ -932,9 +940,7 @@
 void
 PyErr_SetInterrupt(void)
 {
- is_tripped = 1;
- Handlers[SIGINT].tripped = 1;
- Py_AddPendingCall((int (*)(void *))PyErr_CheckSignals, NULL);
+ trip_signal(SIGINT);
 }
 
 void
-- 
Repository URL: http://hg.python.org/cpython
