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

Change-Id: I11f167edfea428d9fab198ff00ff1364932d1b0b
diff --git a/ap/libc/glibc/glibc-2.23/sysdeps/posix/sigwait.c b/ap/libc/glibc/glibc-2.23/sysdeps/posix/sigwait.c
new file mode 100644
index 0000000..b9b3281
--- /dev/null
+++ b/ap/libc/glibc/glibc-2.23/sysdeps/posix/sigwait.c
@@ -0,0 +1,108 @@
+/* Implementation of sigwait function from POSIX.1c.
+   Copyright (C) 1996-2016 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
+
+   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 <stddef.h>		/* For NULL.  */
+#include <sysdep-cancel.h>
+
+/* This is our dummy signal handler we use here.  */
+static void ignore_signal (int sig);
+
+/* Place where to remember which signal we got.  Please note that this
+   implementation cannot be used for the threaded libc.  The
+   libpthread must provide an own version.  */
+static int was_sig;
+
+
+static int
+do_sigwait (const sigset_t *set, int *sig)
+{
+  sigset_t tmp_mask;
+  struct sigaction saved[NSIG];
+  struct sigaction action;
+  int save_errno;
+  int this;
+
+  /* Prepare set.  */
+  __sigfillset (&tmp_mask);
+
+  /* Unblock all signals in the SET and register our nice handler.  */
+  action.sa_handler = ignore_signal;
+  action.sa_flags = 0;
+  __sigfillset (&action.sa_mask);	/* Block all signals for handler.  */
+
+  /* Make sure we recognize error conditions by setting WAS_SIG to a
+     value which does not describe a legal signal number.  */
+  was_sig = -1;
+
+  for (this = 1; this < NSIG; ++this)
+    if (__sigismember (set, this))
+      {
+	/* Unblock this signal.  */
+	__sigdelset (&tmp_mask, this);
+
+	/* Register temporary action handler.  */
+	if (__sigaction (this, &action, &saved[this]) != 0)
+	  goto restore_handler;
+      }
+
+  /* Now we can wait for signals.  */
+  __sigsuspend (&tmp_mask);
+
+ restore_handler:
+  save_errno = errno;
+
+  while (--this >= 1)
+    if (__sigismember (set, this))
+      /* We ignore errors here since we must restore all handlers.  */
+      __sigaction (this, &saved[this], NULL);
+
+  __set_errno (save_errno);
+
+  /* Store the result and return.  */
+  *sig = was_sig;
+  return was_sig == -1 ? -1 : 0;
+}
+
+
+int
+__sigwait (const sigset_t *set, int *sig)
+{
+  if (SINGLE_THREAD_P)
+    return do_sigwait (set, sig);
+
+  int oldtype = LIBC_CANCEL_ASYNC ();
+
+  int result = do_sigwait (set, sig);
+
+  LIBC_CANCEL_RESET (oldtype);
+
+  return result;
+}
+libc_hidden_def (__sigwait)
+weak_alias (__sigwait, sigwait)
+
+
+static void
+ignore_signal (int sig)
+{
+  /* Remember the signal.  */
+  was_sig = sig;
+}