Merge pull request #2260 from xmcclure/fix-testwaitany

Cleanup and crash fix around UnixSignal.WaitAny (bug #36214)

2 files changed, 7 insertions, 2 deletions

diff --git a/mcs/class/Mono.Posix/Mono.Unix/UnixSignal.cs b/mcs/class/Mono.Posix/Mono.Unix/UnixSignal.cs
index fe1f8beba8e..8e4eb5b8463 100644
--- a/mcs/class/Mono.Posix/Mono.Unix/UnixSignal.cs
+++ b/mcs/class/Mono.Posix/Mono.Unix/UnixSignal.cs
@@ -150,10 +150,12 @@ namespace Mono.Unix {
 			set {Interlocked.Exchange (ref Info->count, value);}
 		}
 
+		// signum, count, write_fd, pipecnt, and pipelock are read from a signal handler thread
+		// count and pipelock are both read and written from the signal handler thread
 		[Map]
 		struct SignalInfo {
-			public int signum, count, read_fd, write_fd, have_handler, pipecnt;
-			public IntPtr handler;
+			public int signum, count, read_fd, write_fd, pipecnt, pipelock, have_handler;
+			public IntPtr handler; // Backed-up handler to restore when signal unregistered
 		}
 
 		#region WaitHandle overrides
diff --git a/mcs/class/Mono.Posix/Test/Mono.Unix/UnixSignalTest.cs b/mcs/class/Mono.Posix/Test/Mono.Unix/UnixSignalTest.cs
index 14613104d9b..d621ad51d45 100644
--- a/mcs/class/Mono.Posix/Test/Mono.Unix/UnixSignalTest.cs
+++ b/mcs/class/Mono.Posix/Test/Mono.Unix/UnixSignalTest.cs
@@ -456,6 +456,7 @@ namespace MonoTests.Mono.Unix {
 				s.Close ();
 		}
 
+		// Create thread that issues many signals from a set of harmless signals
 		static Thread CreateRaiseStormThread (int max)
 		{
 			return new Thread (delegate () {
@@ -486,6 +487,7 @@ namespace MonoTests.Mono.Unix {
 			CloseSignals (usignals);
 		}
 
+		// Create thread that repeatedly registers then unregisters signal handlers
 		static Thread CreateSignalCreatorThread ()
 		{
 			return new Thread (delegate () {
@@ -523,6 +525,7 @@ namespace MonoTests.Mono.Unix {
 			CloseSignals (usignals);
 		}
 
+		// Create thread that blocks until at least one of the given signals is received
 		static Thread CreateWaitAnyThread (params UnixSignal[] usignals)
 		{
 			return new Thread (delegate () {