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/*
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)opendir.c 8.2 (Berkeley) 2/12/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/param.h>
#include <sys/stat.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
/*
* open a directory.
*/
DIR *
opendir(name)
const char *name;
{
register DIR *dirp;
register int fd;
int saved_errno;
struct stat sb;
/*
* stat() before open() because opening of special files may be
* harmful. fstat() after open because the file may have changed.
*/
if (stat(name, &sb) != 0)
return NULL;
if (!S_ISDIR(sb.st_mode)) {
errno = ENOTDIR;
return NULL;
}
if ((fd = open(name, O_RDONLY | O_NONBLOCK)) == -1)
return NULL;
dirp = NULL;
if (fstat(fd, &sb) != 0)
goto fail;
if (!S_ISDIR(sb.st_mode)) {
errno = ENOTDIR;
goto fail;
}
if (fcntl(fd, F_SETFD, FD_CLOEXEC) == -1 ||
(dirp = malloc(sizeof(DIR))) == NULL)
goto fail;
/*
* Use the system page size if that is a multiple of DIRBLKSIZ
* this could speed things up in some cases we hope
*/
dirp->dd_len = getpagesize();
if ((dirp->dd_len % DIRBLKSIZ) != 0)
dirp->dd_len = DIRBLKSIZ;
dirp->dd_buf = malloc(dirp->dd_len);
if (dirp->dd_buf == NULL)
goto fail;
dirp->dd_fd = fd;
dirp->dd_loc = 0;
dirp->dd_seek = 0;
/*
* Set up seek point for rewinddir.
*/
dirp->dd_rewind = telldir(dirp);
return dirp;
fail:
saved_errno = errno;
free(dirp);
close(fd);
errno = saved_errno;
return NULL;
}
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