zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/build/uClibc/libc/signal/signal.c b/ap/build/uClibc/libc/signal/signal.c
new file mode 100644
index 0000000..644617c
--- /dev/null
+++ b/ap/build/uClibc/libc/signal/signal.c
@@ -0,0 +1,54 @@
+/* BSD-like signal function.
+   Copyright (C) 1991,1992,1996,1997,2000,2002,2005
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>	/* For the real memset prototype.  */
+
+sigset_t _sigintr attribute_hidden;		/* Set by siginterrupt.  */
+
+/* Set the handler for the signal SIG to HANDLER,
+   returning the old handler, or SIG_ERR on error.  */
+__sighandler_t
+signal (int sig, __sighandler_t handler)
+{
+  struct sigaction act, oact;
+
+  /* Check signal extents to protect __sigismember.  */
+  if (handler == SIG_ERR || sig < 1 || sig >= NSIG)
+    {
+      __set_errno (EINVAL);
+      return SIG_ERR;
+    }
+
+  act.sa_handler = handler;
+  __sigemptyset (&act.sa_mask);
+  __sigaddset (&act.sa_mask, sig);
+  act.sa_flags = __sigismember (&_sigintr, sig) ? 0 : SA_RESTART;
+  /* In Linux (as of 2.6.25), fails only if sig is SIGKILL or SIGSTOP */
+  if (sigaction (sig, &act, &oact) < 0)
+    return SIG_ERR;
+
+  return oact.sa_handler;
+}
+libc_hidden_def(signal)
+#ifdef __UCLIBC_SUSV3_LEGACY__
+strong_alias(signal,bsd_signal)
+#endif