dirent/scandir.c

   1 /* Copyright (C) 1992, 1993, 1994, 1995, 1996 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
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <dirent.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <errno.h>
  24
  25 int
  26 DEFUN(scandir, (dir, namelist, select, cmp),
  27       CONST char *dir AND
  28       struct dirent ***namelist AND
  29       int EXFUN((*select), (struct dirent *)) AND
  30       int EXFUN((*cmp), (CONST PTR, CONST PTR)))
  31 {
  32   DIR *dp = opendir (dir);
  33   struct dirent **v = NULL;
  34   size_t vsize = 0, i;
  35   struct dirent *d;
  36   int save;
  37
  38   if (dp == NULL)
  39     return -1;
  40
  41   save = errno;
  42   errno = 0;
  43
  44   i = 0;
  45   while ((d = readdir (dp)) != NULL)
  46     if (select == NULL || (*select) (d))
  47       {
  48         size_t dsize;
  49
  50         if (i == vsize)
  51           {
  52             struct dirent **new;
  53             if (vsize == 0)
  54               vsize = 10;
  55             else
  56               vsize *= 2;
  57             new = (struct dirent **) realloc (v, vsize * sizeof (*v));
  58             if (new == NULL)
  59               {
  60               lose:
  61                 errno = ENOMEM;
  62                 break;
  63               }
  64             v = new;
  65           }
  66
  67         dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
  68         v[i] = (struct dirent *) malloc (dsize);
  69         if (v[i] == NULL)
  70           goto lose;
  71
  72         memcpy (v[i++], d, dsize);
  73       }
  74
  75   if (errno != 0)
  76     {
  77       save = errno;
  78       (void) closedir (dp);
  79       while (i > 0)
  80         free (v[--i]);
  81       free (v);
  82       errno = save;
  83       return -1;
  84     }
  85
  86   (void) closedir (dp);
  87   errno = save;
  88
  89   /* Sort the list if we have a comparison function to sort with.  */
  90   if (cmp != NULL)
  91     qsort (v, i, sizeof (*v), cmp);
  92   *namelist = v;
  93   return i;
  94 }