Protect against spurious wake-ups while waiting on the condition variable

when tearing down the notifier thread [Bug# 1222872].

2 files changed, 14 insertions, 6 deletions

diff --git a/ChangeLog b/ChangeLog
index 592000a..e9b1abb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2005-07-01  Zoran Vasiljevic <vasiljevic@users.sourceforge.net>
+
+	* unix/tclUnixNotfy.c: protect against spurious wake-ups while
+	waiting on the condition variable when tearing down the notifier
+	thread [Bug# 1222872].
+
 2005-06-28  Mo DeJong  <mdejong@users.sourceforge.net>
 
 	* generic/tclExecute.c (TclExecuteByteCode):
diff --git a/unix/tclUnixNotfy.c b/unix/tclUnixNotfy.c
index 1976433..b0052d4 100644
--- a/unix/tclUnixNotfy.c
+++ b/unix/tclUnixNotfy.c
@@ -11,7 +11,7 @@
  * See the file "license.terms" for information on usage and redistribution
  * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
  *
- * RCS: @(#) $Id: tclUnixNotfy.c,v 1.26 2005/06/01 09:38:05 dkf Exp $
+ * RCS: @(#) $Id: tclUnixNotfy.c,v 1.27 2005/07/01 10:29:12 vasiljevic Exp $
  */
 
 #ifndef HAVE_COREFOUNDATION /* Darwin/Mac OS X CoreFoundation notifier
@@ -273,7 +273,7 @@ Tcl_FinalizeNotifier(clientData)
      */
 
     if (notifierCount == 0) {
-	int result, ignored;
+	int result;
 	if (triggerPipe < 0) {
 	    Tcl_Panic("Tcl_FinalizeNotifier: notifier pipe not initialized");
 	}
@@ -286,13 +286,15 @@ Tcl_FinalizeNotifier(clientData)
 	 * not just close the pipe and check for EOF in the notifier
 	 * thread because if a background child process was created with
 	 * exec, select() would not register the EOF on the pipe until the
-	 * child processes had terminated. [Bug: 4139]
+	 * child processes had terminated. [Bug: 4139] [Bug: 1222872]
 	 */
+
 	write(triggerPipe, "q", 1);
 	close(triggerPipe);
-
-	Tcl_ConditionWait(&notifierCV, &notifierMutex, NULL);
-	result = Tcl_JoinThread(notifierThread, &ignored);
+	while(triggerPipe >= 0) {
+	    Tcl_ConditionWait(&notifierCV, &notifierMutex, NULL);
+	}
+	result = Tcl_JoinThread(notifierThread, NULL);
 	if (result) {
 	    Tcl_Panic("Tcl_FinalizeNotifier: unable to join notifier thread");
 	}