debug/wcscpy_chk.c

   1 /* Copyright (C) 1995-2022 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <stddef.h>
  19 #include <wchar.h>
  20
  21
  22 /* Copy SRC to DEST.  */
  23 wchar_t *
  24 __wcscpy_chk (wchar_t *dest, const wchar_t *src, size_t n)
  25 {
  26   wint_t c;
  27   wchar_t *wcp;
  28
  29   if (__alignof__ (wchar_t) >= sizeof (wchar_t))
  30     {
  31       const ptrdiff_t off = dest - src - 1;
  32
  33       wcp = (wchar_t *) src;
  34
  35       do
  36         {
  37           if (__glibc_unlikely (n-- == 0))
  38             __chk_fail ();
  39           c = *wcp++;
  40           wcp[off] = c;
  41         }
  42       while (c != L'\0');
  43     }
  44   else
  45     {
  46       wcp = dest;
  47
  48       do
  49         {
  50           if (__glibc_unlikely (n-- == 0))
  51             __chk_fail ();
  52           c = *src++;
  53           *wcp++ = c;
  54         }
  55       while (c != L'\0');
  56     }
  57
  58   return dest;
  59 }