readdir.c revision 4fd606d1f5abe38e1f42c38de1d2e895166bd0f4
/** @file
Get next entry in a directory.
Copyright (c) 2010 - 2011, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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. 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
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SUCH DAMAGE.
NetBSD: readdir.c,v 1.24 2008/05/04 18:53:26 tonnerre Exp
readdir.c 8.3 (Berkeley) 9/29/94
*/
#include <sys/cdefs.h>
#include <namespace.h>
#include <reentrant.h>
#include <extern.h>
#include <sys/param.h>
#include <sys/stdint.h>
#include <stdio.h>
#include <dirent.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
/*
* get next entry in a directory.
*/
struct dirent *
_readdir_unlocked(DIR *dirp, int skipdeleted)
{
struct dirent *dp;
for (;;) {
if (dirp->dd_loc >= dirp->dd_size) {
if (dirp->dd_flags & __DTF_READALL)
return (NULL);
dirp->dd_loc = 0;
}
if (dirp->dd_loc == 0 && !(dirp->dd_flags & __DTF_READALL)) {
dirp->dd_size = (long)read(dirp->dd_fd, dirp->dd_buf, (size_t)dirp->dd_len);
if (dirp->dd_size <= 0)
return (NULL);
}
dp = (struct dirent *) (void *)(dirp->dd_buf + (size_t)dirp->dd_loc);
if ((intptr_t)dp & _DIRENT_ALIGN(dp))/* bogus pointer check */
return (NULL);
dirp->dd_loc += (long)dp->Size;
if ((dp->Attribute & DT_HIDDEN) && (dirp->dd_flags & DTF_HIDEW))
continue;
return (dp);
}
}
struct dirent *
readdir(DIR *dirp)
{
struct dirent *dp;
#ifdef _REENTRANT
if (__isthreaded) {
mutex_lock((mutex_t *)dirp->dd_lock);
dp = _readdir_unlocked(dirp, 1);
mutex_unlock((mutex_t *)dirp->dd_lock);
}
else
#endif
dp = _readdir_unlocked(dirp, 1);
return (dp);
}
int
readdir_r(DIR *dirp, struct dirent *entry, struct dirent **result)
{
struct dirent *dp;
int saved_errno;
saved_errno = errno;
errno = 0;
#ifdef _REENTRANT
if (__isthreaded) {
mutex_lock((mutex_t *)dirp->dd_lock);
if ((dp = _readdir_unlocked(dirp, 1)) != NULL)
memcpy(entry, dp, (size_t)_DIRENT_SIZE(dp));
mutex_unlock((mutex_t *)dirp->dd_lock);
}
else
#endif
if ((dp = _readdir_unlocked(dirp, 1)) != NULL)
memcpy(entry, dp, (size_t)_DIRENT_SIZE(dp));
if (errno != 0) {
if (dp == NULL)
return (errno);
} else
errno = saved_errno;
if (dp != NULL)
*result = entry;
else
*result = NULL;
return (0);
}