glibc/dirent/scandirat.c

155 lines
3.5 KiB
C

/* Copyright (C) 1992-2012 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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* We need to avoid the header declaration of scandir64, because
the types don't match scandir and then the compiler will
complain about the mismatch when we do the alias below. */
#define scandirat64 __renamed_scandirat64
#include <dirent.h>
#undef scandirat64
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <bits/libc-lock.h>
#ifndef SCANDIRAT
# define SCANDIRAT scandirat
# define READDIR __readdir
# define DIRENT_TYPE struct dirent
#endif
#ifndef SKIP_SCANDIR_CANCEL
void
__scandir_cancel_handler (void *arg)
{
struct scandir_cancel_struct *cp = arg;
size_t i;
void **v = cp->v;
for (i = 0; i < cp->cnt; ++i)
free (v[i]);
free (v);
(void) __closedir (cp->dp);
}
#endif
int
SCANDIRAT (dfd, dir, namelist, select, cmp)
int dfd;
const char *dir;
DIRENT_TYPE ***namelist;
int (*select) (const DIRENT_TYPE *);
int (*cmp) (const DIRENT_TYPE **, const DIRENT_TYPE **);
{
DIR *dp = __opendirat (dfd, dir);
DIRENT_TYPE **v = NULL;
size_t vsize = 0;
struct scandir_cancel_struct c;
DIRENT_TYPE *d;
int save;
if (dp == NULL)
return -1;
save = errno;
__set_errno (0);
c.dp = dp;
c.v = NULL;
c.cnt = 0;
__libc_cleanup_push (__scandir_cancel_handler, &c);
while ((d = READDIR (dp)) != NULL)
{
int use_it = select == NULL;
if (! use_it)
{
use_it = select (d);
/* The select function might have changed errno. It was
zero before and it need to be again to make the latter
tests work. */
__set_errno (0);
}
if (use_it)
{
DIRENT_TYPE *vnew;
size_t dsize;
/* Ignore errors from select or readdir */
__set_errno (0);
if (__builtin_expect (c.cnt == vsize, 0))
{
DIRENT_TYPE **new;
if (vsize == 0)
vsize = 10;
else
vsize *= 2;
new = (DIRENT_TYPE **) realloc (v, vsize * sizeof (*v));
if (new == NULL)
break;
v = new;
c.v = (void *) v;
}
dsize = &d->d_name[_D_ALLOC_NAMLEN (d)] - (char *) d;
vnew = (DIRENT_TYPE *) malloc (dsize);
if (vnew == NULL)
break;
v[c.cnt++] = (DIRENT_TYPE *) memcpy (vnew, d, dsize);
}
}
if (__builtin_expect (errno, 0) != 0)
{
save = errno;
while (c.cnt > 0)
free (v[--c.cnt]);
free (v);
c.cnt = -1;
}
else
{
/* Sort the list if we have a comparison function to sort with. */
if (cmp != NULL)
qsort (v, c.cnt, sizeof (*v),
(int (*) (const void *, const void *)) cmp);
*namelist = v;
}
__libc_cleanup_pop (0);
(void) __closedir (dp);
__set_errno (save);
return c.cnt;
}
libc_hidden_def (SCANDIRAT)
#ifdef _DIRENT_MATCHES_DIRENT64
weak_alias (scandirat, scandirat64)
#endif