Fix incorrect implementation to clear per-thread pending signals

	* sigproc.cc (class pending_signals): Drop sigproc_init friendship.
	(pending_signals::clear): Fix implementation to avoid subsequent
	endless loop in wait_sig.  Improve comment.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

1 files changed, 11 insertions, 5 deletions

diff --git a/winsup/cygwin/sigproc.cc b/winsup/cygwin/sigproc.cc
index 387a71a69..fbc738d4f 100644
--- a/winsup/cygwin/sigproc.cc
+++ b/winsup/cygwin/sigproc.cc
@@ -82,7 +82,6 @@ public:
   void clear (_cygtls *tls);
   friend void __reg1 sig_dispatch_pending (bool);
   friend void WINAPI wait_sig (VOID *arg);
-  friend void sigproc_init ();
 };
 
 Static pending_signals sigq;
@@ -398,14 +397,21 @@ sig_clear (int sig)
   sigq.clear (sig);
 }
 
-/* Clear pending signals of specific thread.  Called from
+/* Clear pending signals of specific thread.  Called under TLS lock from
    _cygtls::remove_pending_sigs. */
 void
 pending_signals::clear (_cygtls *tls)
 {
-  for (int sig = 0; sig < NSIG + 1; ++sig)
-    if (sigs[sig].sigtls == tls)
-      clear (sig);
+  sigpacket *q = &start, *qnext;
+
+  while ((qnext = q->next))
+    {
+      if (qnext->sigtls == tls)
+	{
+	  q->next = qnext->next;
+	  qnext->si.si_signo = 0;
+	}
+    }
 }
 
 /* Clear pending signals of specific thread.  Called from _cygtls::remove */