sysdeps/generic/dl-origin.h

   1 /* Find path of executable.
   2    Copyright (C) 1998 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 /* Generally it is not possible to implement this.  We have to fall
  22    back on a solution where the user provides the information.  */
  23 extern const char *_dl_origin_path;
  24
  25 static inline const char *
  26 get_origin (void)
  27 {
  28   char *result = (char *) -1;
  29   /* We use the environment variable LD_ORIGIN_PATH.  If it is set make
  30      a copy and strip out trailing slashes.  */
  31   if (_dl_origin_path != NULL)
  32     {
  33       size_t len = strlen (_dl_origin_path);
  34       result = malloc (len + 1);
  35       if (result == NULL)
  36         result = (char *) -1;
  37       else
  38         {
  39           char *cp = __mempcpy (result, _dl_origin_path, len);
  40           while (cp > result + 1 && cp[-1] == '/')
  41             --cp;
  42           *cp = '\0';
  43         }
  44     }
  45
  46   return result;
  47 }