首先,POSIX规范规定文件描述符需要支持close-on-exec属性,修改前的vfs不支持close-on-exec,当exec系列函数执行时,进程所有的文件将会被关闭(0,1,2也重新被打开)。但是,系统有些时候是不能在exec时关闭全部文件的,例如在执行exec之前,就需要重定向进程的某些文件描述符时(使用dup2),就希望该文件不被关闭,继续保持重定向属性,shell执行进程并重定向其标准输出到文件,这是我们经常做的事情。 BREAKING CHANGE: 执行exec类函数后,进程拥有的文件描述符情况发生变化:修改前,默认关闭所有的进程文件描述符,0,1,2重新打开;修改后,除非文件描述符拥有FD_CLOEXEC标记,否则该描述符不会被关闭。 re #I3U81W Change-Id: I54e841ac88e9835ec23e97de0cbc906c4e11f5a4 Signed-off-by: Guangyao Ma <guangyao.ma@outlook.com>
94 lines
3.1 KiB
C
94 lines
3.1 KiB
C
/*
|
|
* Copyright (c) 2013-2019 Huawei Technologies Co., Ltd. All rights reserved.
|
|
* Copyright (c) 2020-2021 Huawei Device Co., Ltd. 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 copyright holder 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
|
|
*/
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include "errno.h"
|
|
#include "stdlib.h"
|
|
#include "string.h"
|
|
#include "dirent.h"
|
|
#include "unistd.h"
|
|
#include "sys/select.h"
|
|
#include "sys/stat.h"
|
|
#include "sys/prctl.h"
|
|
#include "fs/dirent_fs.h"
|
|
#include "vnode.h"
|
|
|
|
/****************************************************************************
|
|
* Name: fscheck
|
|
****************************************************************************/
|
|
int fscheck(const char *path)
|
|
{
|
|
int ret;
|
|
struct Vnode *vnode = NULL;
|
|
struct fs_dirent_s *dir = NULL;
|
|
|
|
/* Find the node matching the path. */
|
|
VnodeHold();
|
|
ret = VnodeLookup(path, &vnode, 0);
|
|
if (ret != OK) {
|
|
VnodeDrop();
|
|
goto errout;
|
|
}
|
|
|
|
dir = (struct fs_dirent_s *)zalloc(sizeof(struct fs_dirent_s));
|
|
if (!dir) {
|
|
/* Insufficient memory to complete the operation.*/
|
|
ret = -ENOMEM;
|
|
VnodeDrop();
|
|
goto errout;
|
|
}
|
|
|
|
if (vnode->vop && vnode->vop->Fscheck) {
|
|
ret = vnode->vop->Fscheck(vnode, dir);
|
|
if (ret != OK) {
|
|
VnodeDrop();
|
|
goto errout_with_direntry;
|
|
}
|
|
} else {
|
|
ret = -ENOSYS;
|
|
VnodeDrop();
|
|
goto errout_with_direntry;
|
|
}
|
|
VnodeDrop();
|
|
|
|
free(dir);
|
|
return 0;
|
|
|
|
errout_with_direntry:
|
|
free(dir);
|
|
errout:
|
|
set_errno(-ret);
|
|
return VFS_ERROR;
|
|
}
|