dirent/scandir.c

   1 /* Copyright (C) 1992-1998, 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <dirent.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <errno.h>
  23
  24 int
  25 scandir (dir, namelist, select, cmp)
  26      const char *dir;
  27      struct dirent ***namelist;
  28      int (*select) (const struct dirent *);
  29      int (*cmp) (const void *, const void *);
  30 {
  31   DIR *dp = __opendir (dir);
  32   struct dirent **v = NULL;
  33   size_t vsize = 0, i;
  34   struct dirent *d;
  35   int save;
  36
  37   if (dp == NULL)
  38     return -1;
  39
  40   save = errno;
  41   __set_errno (0);
  42
  43   i = 0;
  44   while ((d = __readdir (dp)) != NULL)
  45     if (select == NULL || (*select) (d))
  46       {
  47         struct dirent *vnew;
  48         size_t dsize;
  49
  50         /* Ignore errors from select or readdir */
  51         __set_errno (0);
  52
  53         if (__builtin_expect (i == vsize, 0))
  54           {
  55             struct dirent **new;
  56             if (vsize == 0)
  57               vsize = 10;
  58             else
  59               vsize *= 2;
  60             new = (struct dirent **) realloc (v, vsize * sizeof (*v));
  61             if (new == NULL)
  62               break;
  63             v = new;
  64           }
  65
  66         dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
  67         vnew = (struct dirent *) malloc (dsize);
  68         if (vnew == NULL)
  69           break;
  70
  71         v[i++] = (struct dirent *) memcpy (vnew, d, dsize);
  72       }
  73
  74   if (__builtin_expect (errno, 0) != 0)
  75     {
  76       save = errno;
  77       (void) __closedir (dp);
  78       while (i > 0)
  79         free (v[--i]);
  80       free (v);
  81       __set_errno (save);
  82       return -1;
  83     }
  84
  85   (void) __closedir (dp);
  86   __set_errno (save);
  87
  88   /* Sort the list if we have a comparison function to sort with.  */
  89   if (cmp != NULL)
  90     qsort (v, i, sizeof (*v), cmp);
  91   *namelist = v;
  92   return i;
  93 }