google3/third_party/grte/v4_src/glibc-2.19/debug/wcscpy_chk.c

/* Copyright (C) 1995-2014 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1995.

   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 <stddef.h>
#include <wchar.h>


/* Copy SRC to DEST.  */
wchar_t *
__wcscpy_chk (wchar_t *dest, const wchar_t *src, size_t n)
{
  wint_t c;
  wchar_t *wcp;

  if (__alignof__ (wchar_t) >= sizeof (wchar_t))
    {
      const ptrdiff_t off = dest - src - 1;

      wcp = (wchar_t *) src;

      do
	{
	  if (__builtin_expect (n-- == 0, 0))
	    __chk_fail ();
	  c = *wcp++;
	  wcp[off] = c;
	}
      while (c != L'\0');
    }
  else
    {
      wcp = dest;

      do
	{
	  if (__builtin_expect (n-- == 0, 0))
	    __chk_fail ();
	  c = *src++;
	  *wcp++ = c;
	}
      while (c != L'\0');
    }

  return dest;
}