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/* Stub for readlink(). 
   Copyright (C) 2003-2007, 2009-2013 Free Software Foundation, Inc. 
 
   This program is free software: you can redistribute it and/or modify 
   it under the terms of the GNU General Public License as published by 
   the Free Software Foundation; either version 3 of the License, or 
   (at your option) any later version. 
 
   This program 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 General Public License for more details. 
 
   You should have received a copy of the GNU General Public License 
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */ 
 
#include <config.h> 
 
/* Specification.  */ 
#include <unistd.h> 
 
#include <errno.h> 
#include <string.h> 
#include <sys/stat.h> 
 
#if !HAVE_READLINK 
 
/* readlink() substitute for systems that don't have a readlink() function, 
   such as DJGPP 2.03 and mingw32.  */ 
 
ssize_t 
readlink (const char *name, char *buf _GL_UNUSED, 
          size_t bufsize _GL_UNUSED) 
{ 
  struct stat statbuf; 
 
  /* In general we should use lstat() here, not stat().  But on platforms 
     without symbolic links, lstat() - if it exists - would be equivalent to 
     stat(), therefore we can use stat().  This saves us a configure check.  */ 
  if (stat (name, &statbuf) >= 0) 
    errno = EINVAL; 
  return -1; 
} 
 
#else /* HAVE_READLINK */ 
 
# undef readlink 
 
/* readlink() wrapper that uses correct types, for systems like cygwin 
   1.5.x where readlink returns int, and which rejects trailing slash, 
   for Solaris 9.  */ 
 
ssize_t 
rpl_readlink (const char *name, char *buf, size_t bufsize) 
{ 
# if READLINK_TRAILING_SLASH_BUG 
  size_t len = strlen (name); 
  if (len && name[len - 1] == '/') 
    { 
      /* Even if name without the slash is a symlink to a directory, 
         both lstat() and stat() must resolve the trailing slash to 
         the directory rather than the symlink.  We can therefore 
         safely use stat() to distinguish between EINVAL and 
         ENOTDIR/ENOENT, avoiding extra overhead of rpl_lstat().  */ 
      struct stat st; 
      if (stat (name, &st) == 0) 
        errno = EINVAL; 
      return -1; 
    } 
# endif /* READLINK_TRAILING_SLASH_BUG */ 
  return readlink (name, buf, bufsize); 
} 
 
#endif /* HAVE_READLINK */