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 Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the 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    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <dirent.h>
  20 #include <stdlib.h>
  21 #include <string.h>
  22 #include <errno.h>
  23
  24 #ifndef SCANDIR
  25 #define SCANDIR scandir
  26 #define READDIR __readdir
  27 #define DIRENT_TYPE struct dirent
  28 #endif
  29
  30 int
  31 SCANDIR (dir, namelist, select, cmp)
  32      const char *dir;
  33      DIRENT_TYPE ***namelist;
  34      int (*select) (const DIRENT_TYPE *);
  35      int (*cmp) (const void *, const void *);
  36 {
  37   DIR *dp = __opendir (dir);
  38   DIRENT_TYPE **v = NULL;
  39   size_t vsize = 0, i;
  40   DIRENT_TYPE *d;
  41   int save;
  42
  43   if (dp == NULL)
  44     return -1;
  45
  46   save = errno;
  47   __set_errno (0);
  48
  49   i = 0;
  50   while ((d = READDIR (dp)) != NULL)
  51     if (select == NULL || (*select) (d))
  52       {
  53         DIRENT_TYPE *vnew;
  54         size_t dsize;
  55
  56         /* Ignore errors from select or readdir */
  57         __set_errno (0);
  58
  59         if (__builtin_expect (i == vsize, 0))
  60           {
  61             DIRENT_TYPE **new;
  62             if (vsize == 0)
  63               vsize = 10;
  64             else
  65               vsize *= 2;
  66             new = (DIRENT_TYPE **) realloc (v, vsize * sizeof (*v));
  67             if (new == NULL)
  68               break;
  69             v = new;
  70           }
  71
  72         dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
  73         vnew = (DIRENT_TYPE *) malloc (dsize);
  74         if (vnew == NULL)
  75           break;
  76
  77         v[i++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize);
  78       }
  79
  80   if (__builtin_expect (errno, 0) != 0)
  81     {
  82       save = errno;
  83       (void) __closedir (dp);
  84       while (i > 0)
  85         free (v[--i]);
  86       free (v);
  87       __set_errno (save);
  88       return -1;
  89     }
  90
  91   (void) __closedir (dp);
  92   __set_errno (save);
  93
  94   /* Sort the list if we have a comparison function to sort with.  */
  95   if (cmp != NULL)
  96     qsort (v, i, sizeof (*v), cmp);
  97   *namelist = v;
  98   return i;
  99 }