scandir.c

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/* Copyright (C) 1992-1998, 2000 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   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., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

/*
 * $Id: scandir.c,v 1.1 2002-12-05 01:50:22 rtv Exp $
 *
 * taken from glibc, modified slightly for standalone compilation, and used as
 * a fallback implementation when scandir() is not available. - BPG
 */

#include <dirent.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

int
scandir(dir, namelist, select, cmp)
     const char *dir;
     struct dirent ***namelist;
     int (*select) (const struct dirent *);
     int (*cmp) (const void *, const void *);
{
  DIR *dp = opendir (dir);
  struct dirent **v = NULL;
  size_t vsize = 0, i;
  struct dirent *d;
  int save;

  if (dp == NULL)
    return -1;

  save = errno;
  errno = 0;

  i = 0;
  while ((d = readdir (dp)) != NULL)
    if (select == NULL || (*select) (d))
      {
        struct dirent *vnew;
        size_t dsize;

        /* Ignore errors from select or readdir */
        errno = 0;

        if (i == vsize)
          {
            struct dirent **new;
            if (vsize == 0)
              vsize = 10;
            else
              vsize *= 2;
            new = (struct dirent **) realloc (v, vsize * sizeof (*v));
            if (new == NULL)
              break;
            v = new;
          }

        dsize = &d->d_name[strlen(d->d_name)+1] - (char *) d;
        vnew = (struct dirent *) malloc (dsize);
        if (vnew == NULL)
          break;

        v[i++] = (struct dirent *) memcpy (vnew, d, dsize);
      }

  if (errno != 0)
    {
      save = errno;
      (void) closedir (dp);
      while (i > 0)
        free (v[--i]);
      free (v);
      errno = save;
      return -1;
    }

  (void) closedir (dp);
  errno = save;

  /* Sort the list if we have a comparison function to sort with.  */
  if (cmp != NULL)
    qsort (v, i, sizeof (*v), cmp);
  *namelist = v;
  return i;
}