[Python-checkins] cpython (3.2): Fixes issue #9535: Fix pending signals that have been received but not

[gregory.p.smith]

http://hg.python.org/cpython/rev/ba45976c2801
changeset:   80358:ba45976c2801
branch:      3.2
parent:      80354:a1db815d0829
user:        Gregory P. Smith <greg at krypto.org>
date:        Sat Nov 10 20:33:07 2012 -0800
summary:
  Fixes issue #9535: Fix pending signals that have been received but not
yet handled by Python to not persist after os.fork() in the child process.

files:
  Misc/NEWS              |   3 +++
  Modules/signalmodule.c |  16 ++++++++++++++++
  2 files changed, 19 insertions(+), 0 deletions(-)


diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -10,6 +10,9 @@
 Core and Builtins
 -----------------
 
+- Issue #9535: Fix pending signals that have been received but not yet
+  handled by Python to not persist after os.fork() in the child process.
+
 - Issue #15001: fix segfault on "del sys.module['__main__']". Patch by Victor
   Stinner.
 
diff --git a/Modules/signalmodule.c b/Modules/signalmodule.c
--- a/Modules/signalmodule.c
+++ b/Modules/signalmodule.c
@@ -987,9 +987,25 @@
     return 0;
 }
 
+static void
+_clear_pending_signals(void)
+{
+    int i;
+    if (!is_tripped)
+        return;
+    is_tripped = 0;
+    for (i = 1; i < NSIG; ++i) {
+        Handlers[i].tripped = 0;
+    }
+}
+
 void
 PyOS_AfterFork(void)
 {
+    /* Clear the signal flags after forking so that they aren't handled
+     * in both processes if they came in just before the fork() but before
+     * the interpreter had an opportunity to call the handlers.  issue9535. */
+    _clear_pending_signals();
 #ifdef WITH_THREAD
     /* PyThread_ReInitTLS() must be called early, to make sure that the TLS API
      * can be called safely. */

-- 
Repository URL: http://hg.python.org/cpython