[Feature][ZXW-33]merge ZXW 0428 version

Change-Id: I11f167edfea428d9fab198ff00ff1364932d1b0b
diff --git a/ap/libc/glibc/glibc-2.23/nptl/pthread_sigmask.c b/ap/libc/glibc/glibc-2.23/nptl/pthread_sigmask.c
new file mode 100644
index 0000000..b87f7fc
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/nptl/pthread_sigmask.c
@@ -0,0 +1,36 @@
+/* Examine and change blocked signals for a thread.  Generic POSIX version.
+   Copyright (C) 2014-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <signal.h>
+#include <pthreadP.h>
+
+#if defined SIGCANCEL || defined SIGTIMER || defined SIGSETXID
+# error "This implementation assumes no internal-only signal numbers."
+#endif
+
+int
+pthread_sigmask (int how, const sigset_t *newmask, sigset_t *oldmask)
+{
+  /* Here we assume that sigprocmask actually does everything right.
+     The only difference is the return value protocol.  */
+  int result = sigprocmask (how, newmask, oldmask);
+  if (result < 0)
+    result = errno;
+  return result;
+}