/* Copyright (C) 1991, 1992 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ian Lance Taylor (ian@airs.com).

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.

The GNU C Library 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
Library General Public License for more details.

You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.

Modified by Ian Lance Taylor for Taylor UUCP, June 1992, and October 1993.  */

#include "uucp.h"

#include "sysdep.h"

#include <errno.h>

#if HAVE_LIMITS_H
#include <limits.h>
#endif

#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif

#if HAVE_OPENDIR
#if HAVE_DIRENT_H
#include <dirent.h>
#else /* ! HAVE_DIRENT_H */
#include <sys/dir.h>
#define dirent direct
#endif /* ! HAVE_DIRENT_H */
#endif /* HAVE_OPENDIR */

#if HAVE_FTW_H
#include <ftw.h>
#endif

#ifndef PATH_MAX
#ifdef MAXPATHLEN
#define PATH_MAX MAXPATHLEN
#else
#define PATH_MAX 1024
#endif
#endif

/* Traverse one level of a directory tree.  */

static int
ftw_dir (dirs, level, descriptors, dir, len, func)
     DIR **dirs;
     int level;
     int descriptors;
     char *dir;
     size_t len;
     int (*func) P((const char *file, struct stat *status, int flag));
{
  int got;
  struct dirent *entry;

  got = 0;

  errno = 0;

  while ((entry = readdir (dirs[level])) != NULL)
    {
      size_t namlen;
      struct stat s;
      int flag, ret, newlev;

      ++got;

      namlen = strlen (entry->d_name);
      if (entry->d_name[0] == '.'
	  && (namlen == 1 ||
	      (namlen == 2 && entry->d_name[1] == '.')))
	{
	  errno = 0;
	  continue;
	}

      if (namlen + len + 1 > PATH_MAX)
	{
#ifdef ENAMETOOLONG
	  errno = ENAMETOOLONG;
#else
	  errno = ENOMEM;
#endif
	  return -1;
	}

      dir[len] = '/';
      memcpy ((dir + len + 1), entry->d_name, namlen + 1);

      if (stat (dir, &s) < 0)
	{
	  if (errno != EACCES)
	    return -1;
	  flag = FTW_NS;
	}
      else if (S_ISDIR (s.st_mode))
	{
	  newlev = (level + 1) % descriptors;

	  if (dirs[newlev] != NULL)
	    closedir (dirs[newlev]);

	  dirs[newlev] = opendir (dir);
	  if (dirs[newlev] != NULL)
	    flag = FTW_D;
	  else
	    {
	      if (errno != EACCES)
		return -1;
	      flag = FTW_DNR;
	    }
	}
      else
	flag = FTW_F;

      ret = (*func) (dir, &s, flag);

      if (flag == FTW_D)
	{
	  if (ret == 0)
	    ret = ftw_dir (dirs, newlev, descriptors, dir,
			   namlen + len + 1, func);
	  if (dirs[newlev] != NULL)
	    {
	      int save;

	      save = errno;
	      closedir (dirs[newlev]);
	      errno = save;
	      dirs[newlev] = NULL;
	    }
	}

      if (ret != 0)
	return ret;

      if (dirs[level] == NULL)
	{
	  int skip;

	  dir[len] = '\0';
	  dirs[level] = opendir (dir);
	  if (dirs[level] == NULL)
	    return -1;
	  skip = got;
	  while (skip-- != 0)
	    {
	      errno = 0;
	      if (readdir (dirs[level]) == NULL)
		return errno == 0 ? 0 : -1;
	    }
	}

      errno = 0;
    }

  return errno == 0 ? 0 : -1;
}

/* Call a function on every element in a directory tree.  */

int
ftw (dir, func, descriptors)
     const char *dir;
     int (*func) P((const char *file, struct stat *status, int flag));
     int descriptors;
{
  DIR **dirs;
  int c;
  DIR **p;
  size_t len;
  char buf[PATH_MAX + 1];
  struct stat s;
  int flag, ret;

  if (descriptors <= 0)
    descriptors = 1;

  dirs = (DIR **) malloc (descriptors * sizeof (DIR *));
  if (dirs == NULL)
    return -1;
  c = descriptors;
  p = dirs;
  while (c-- != 0)
    *p++ = NULL;

  len = strlen (dir);
  memcpy (buf, dir, len + 1);

  if (stat (dir, &s) < 0)
    {
      if (errno != EACCES)
	{
	  free ((pointer) dirs);
	  return -1;
	}
      flag = FTW_NS;
    }
  else if (S_ISDIR (s.st_mode))
    {
      dirs[0] = opendir (dir);
      if (dirs[0] != NULL)
	flag = FTW_D;
      else
	{
	  if (errno != EACCES)
	    {
	      free ((pointer) dirs);
	      return -1;
	    }
	  flag = FTW_DNR;
	}
    }
  else
    flag = FTW_F;

  ret = (*func) (buf, &s, flag);

  if (flag == FTW_D)
    {
      if (ret == 0)
	{
	  if (len == 1 && *buf == '/')
	    len = 0;
	  ret = ftw_dir (dirs, 0, descriptors, buf, len, func);
	}
      if (dirs[0] != NULL)
	{
	  int save;

	  save = errno;
	  closedir (dirs[0]);
	  errno = save;
	}
    }

  free ((pointer) dirs);
  return ret;
}
