dirent/scandir.c

   1 /* Copyright (C) 1992, 1993, 1994, 1995 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 <errno.h>
  23
  24 int
  25 DEFUN(scandir, (dir, namelist, select, cmp),
  26       CONST char *dir AND
  27       struct dirent ***namelist AND
  28       int EXFUN((*select), (struct dirent *)) AND
  29       int EXFUN((*cmp), (CONST PTR, CONST PTR)))
  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   errno = 0;
  42
  43   i = 0;
  44   while ((d = readdir (dp)) != NULL)
  45     if (select == NULL || (*select) (d))
  46       {
  47         if (i == vsize)
  48           {
  49             struct dirent **new;
  50             if (vsize == 0)
  51               vsize = 10;
  52             else
  53               vsize *= 2;
  54             new = (struct dirent **) realloc (v, vsize * sizeof (*v));
  55             if (new == NULL)
  56               {
  57               lose:
  58                 errno = ENOMEM;
  59                 break;
  60               }
  61             v = new;
  62           }
  63
  64         v[i] = (struct dirent *) malloc (sizeof (**v));
  65         if (v[i] == NULL)
  66           goto lose;
  67
  68         *v[i++] = *d;
  69       }
  70
  71   if (errno != 0)
  72     {
  73       save = errno;
  74       (void) closedir (dp);
  75       while (i > 0)
  76         free (v[--i]);
  77       free (v);
  78       errno = save;
  79       return -1;
  80     }
  81
  82   (void) closedir (dp);
  83   errno = save;
  84
  85   /* Sort the list if we have a comparison function to sort with.  */
  86   if (cmp != NULL)
  87     qsort (v, i, sizeof (*v), cmp);
  88   *namelist = v;
  89   return i;
  90 }