io/getwd.c

   1 /* Obsolete function to get current working directory.
   2    Copyright (C) 1991-2015 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <limits.h>
  21 #include <string.h>
  22 #include <unistd.h>
  23
  24
  25 char *
  26 getwd (buf)
  27      char *buf;
  28 {
  29 #ifndef PATH_MAX
  30 #define PATH_MAX 1024
  31 #endif
  32   char tmpbuf[PATH_MAX];
  33
  34   if (buf == NULL)
  35     {
  36       __set_errno (EINVAL);
  37       return NULL;
  38     }
  39
  40   if (__getcwd (tmpbuf, PATH_MAX) == NULL)
  41     {
  42       /* We use 1024 here since it should really be enough and because
  43          this is a safe value.  */
  44       __strerror_r (errno, buf, 1024);
  45       return NULL;
  46     }
  47
  48   /* This is completely unsafe.  Nobody can say how big the user
  49      provided buffer is.  Perhaps the application and the libc
  50      disagree about the value of PATH_MAX.  */
  51   return strcpy (buf, tmpbuf);
  52 }
  53
  54 link_warning (getwd,
  55               "the `getwd' function is dangerous and should not be used.")