zte's code,first commit

Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/build/uClibc/libc/sysdeps/linux/c6x/sigaction.c b/ap/build/uClibc/libc/sysdeps/linux/c6x/sigaction.c
new file mode 100644
index 0000000..ed90f05
--- /dev/null
+++ b/ap/build/uClibc/libc/sysdeps/linux/c6x/sigaction.c
@@ -0,0 +1,124 @@
+/*
+   Copyright (C) 2010 Texas Instruments Incorporated
+   Adapted from i386 version by Mark Salter <msalter@redhat.com>
+
+   Copyright (C) 1997, 1998, 1999, 2000 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 Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.
+
+   Totally hacked up for uClibc by Erik Andersen <andersen@codepoet.org>
+   */
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include <bits/kernel_sigaction.h>
+#ifdef __UCLIBC_HAS_THREADS_NATIVE__
+# include <pthreadP.h>	/* SIGCANCEL */
+#endif
+
+#define SA_RESTORER	0x04000000
+
+extern __typeof(sigaction) __libc_sigaction;
+
+extern void restore_rt(void) __asm__ ("__restore_rt") attribute_hidden;
+extern void restore(void) __asm__ ("__restore") attribute_hidden;
+
+/* If ACT is not NULL, change the action for SIG to *ACT.
+   If OACT is not NULL, put the old action for SIG in *OACT.  */
+int __libc_sigaction (int sig, const struct sigaction *act, struct sigaction *oact)
+{
+    int result;
+    struct kernel_sigaction kact, koact;
+
+#ifdef SIGCANCEL
+    if (sig == SIGCANCEL) {
+	__set_errno (EINVAL);
+	return -1;
+    }
+#endif
+
+    if (act) {
+	kact.k_sa_handler = act->sa_handler;
+	memcpy (&kact.sa_mask, &act->sa_mask, sizeof (kact.sa_mask));
+	kact.sa_flags = act->sa_flags;
+
+	kact.sa_flags = act->sa_flags | SA_RESTORER;
+	kact.sa_restorer = ((act->sa_flags & SA_SIGINFO)
+		? &restore_rt : &restore);
+    }
+
+    /* XXX The size argument hopefully will have to be changed to the
+       real size of the user-level sigset_t.  */
+    result = __syscall_rt_sigaction(sig, act ? __ptrvalue (&kact) : NULL,
+	    oact ? __ptrvalue (&koact) : NULL, _NSIG / 8);
+
+    if (oact && result >= 0) {
+	oact->sa_handler = koact.k_sa_handler;
+	memcpy (&oact->sa_mask, &koact.sa_mask, sizeof (oact->sa_mask));
+	oact->sa_flags = koact.sa_flags;
+	oact->sa_restorer = koact.sa_restorer;
+    }
+    return result;
+}
+
+#ifndef LIBC_SIGACTION
+# ifndef __UCLIBC_HAS_THREADS__
+strong_alias(__libc_sigaction,sigaction)
+libc_hidden_def(sigaction)
+# else
+weak_alias(__libc_sigaction,sigaction)
+libc_hidden_weak(sigaction)
+# endif
+#endif
+
+
+/* NOTE: Please think twice before making any changes to the bits of
+   code below.  GDB needs some intimate knowledge about it to
+   recognize them as signal trampolines, and make backtraces through
+   signal handlers work right.  Important are both the names
+   (__restore and __restore_rt) and the exact instruction sequence.
+   If you ever feel the need to make any changes, please notify the
+   appropriate GDB maintainer.  */
+
+#define RESTORE(name, syscall) RESTORE2 (name, syscall)
+#define RESTORE2(name, syscall) \
+__asm__						\
+  (						\
+   "    .text\n"				\
+   "    .global " #name "\n"			\
+   "__" #name ":\n"				\
+   "	MVK " #syscall ",B0\n"			\
+   "	SWE\n"					\
+   "	NOP\n"					\
+   "	NOP\n"					\
+   "	NOP\n"					\
+   "	NOP\n"					\
+   "	NOP\n"					\
+   "	NOP\n"					\
+   );
+
+#ifdef __NR_rt_sigaction
+/* The return code for realtime-signals.  */
+RESTORE (restore_rt, __NR_rt_sigreturn)
+#endif
+
+#ifdef __NR_sigreturn
+/* For the boring old signals.  */
+RESTORE (restore, __NR_sigreturn)
+#endif