/* Work around platform bugs in stat.

   Copyright (C) 2009-2015 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/>.  */

/* written by Eric Blake */

/* If the user's config.h happens to include <sys/stat.h>, let it include only

   the system's <sys/stat.h> here, so that orig_stat doesn't recurse to

   rpl_stat.  */

#define __need_system_sys_stat_h

#include <config.h>

/* Get the original definition of stat.  It might be defined as a macro.  */

#include <sys/types.h>

#include <sys/stat.h>

#undef __need_system_sys_stat_h

#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__

# if _GL_WINDOWS_64_BIT_ST_SIZE

#  undef stat /* avoid warning on mingw64 with _FILE_OFFSET_BITS=64 */

#  define stat _stati64

#  define REPLACE_FUNC_STAT_DIR 1

#  undef REPLACE_FUNC_STAT_FILE

# elif REPLACE_FUNC_STAT_FILE

/* mingw64 has a broken stat() function, based on _stat(), in libmingwex.a.

   Bypass it.  */

#  define stat _stat

#  define REPLACE_FUNC_STAT_DIR 1

#  undef REPLACE_FUNC_STAT_FILE

# endif

#endif

static int

orig_stat (const char *filename, struct stat *buf)

{

  return stat (filename, buf);

}

/* Specification.  */

/* Write "sys/stat.h" here, not <sys/stat.h>, otherwise OSF/1 5.1 DTK cc

   eliminates this include because of the preliminary #include <sys/stat.h>

   above.  */

#include "sys/stat.h"

#include <errno.h>

#include <limits.h>

#include <stdbool.h>

#include <string.h>

#include "dosname.h"

#include "verify.h"

#if REPLACE_FUNC_STAT_DIR

# include "pathmax.h"

  /* The only known systems where REPLACE_FUNC_STAT_DIR is needed also

     have a constant PATH_MAX.  */

# ifndef PATH_MAX

#  error "Please port this replacement to your platform"

# endif

#endif

/* Store information about NAME into ST.  Work around bugs with

   trailing slashes.  Mingw has other bugs (such as st_ino always

   being 0 on success) which this wrapper does not work around.  But

   at least this implementation provides the ability to emulate fchdir

   correctly.  */

int

rpl_stat (char const *name, struct stat *st)

{

  int result = orig_stat (name, st);

#if REPLACE_FUNC_STAT_FILE

  /* Solaris 9 mistakenly succeeds when given a non-directory with a

     trailing slash.  */

  if (result == 0 && !S_ISDIR (st->st_mode))

    {

      size_t len = strlen (name);

      if (ISSLASH (name[len - 1]))

        {

          errno = ENOTDIR;

          return -1;

        }

    }

#endif /* REPLACE_FUNC_STAT_FILE */

#if REPLACE_FUNC_STAT_DIR

  if (result == -1 && errno == ENOENT)

    {

      /* Due to mingw's oddities, there are some directories (like

         c:\) where stat() only succeeds with a trailing slash, and

         other directories (like c:\windows) where stat() only

         succeeds without a trailing slash.  But we want the two to be

         synonymous, since chdir() manages either style.  Likewise, Mingw also

         reports ENOENT for names longer than PATH_MAX, when we want

         ENAMETOOLONG, and for stat("file/"), when we want ENOTDIR.

         Fortunately, mingw PATH_MAX is small enough for stack

         allocation.  */

      char fixed_name[PATH_MAX + 1] = {0};

      size_t len = strlen (name);

      bool check_dir = false;

      verify (PATH_MAX <= 4096);

      if (PATH_MAX <= len)

        errno = ENAMETOOLONG;

      else if (len)

        {

          strcpy (fixed_name, name);

          if (ISSLASH (fixed_name[len - 1]))

            {

              check_dir = true;

              while (len && ISSLASH (fixed_name[len - 1]))

                fixed_name[--len] = '\0';

              if (!len)

                fixed_name[0] = '/';

            }

          else

            fixed_name[len++] = '/';

          result = orig_stat (fixed_name, st);

          if (result == 0 && check_dir && !S_ISDIR (st->st_mode))

            {

              result = -1;

              errno = ENOTDIR;

            }

        }

    }

#endif /* REPLACE_FUNC_STAT_DIR */

  return result;

}