openharmony_kernel_liteos_m/components/fs/vfs/vfs_files.c

99 lines
3.0 KiB
C

/*
* Copyright (c) 2022-2022 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.
*/
#include "vfs_files.h"
#include "errno.h"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"
#include "los_config.h"
#include "vfs_config.h"
#include "vfs_mount.h"
#include "vfs_operations.h"
static struct File g_files[NR_OPEN_DEFAULT];
int FileToFd(const struct File *file)
{
if (file == NULL) {
return (int)LOS_NOK;
}
return file - g_files + MIN_START_FD;
}
struct File *FdToFile(int fd)
{
if ((fd < MIN_START_FD) || (fd >= CONFIG_NFILE_DESCRIPTORS)) {
return NULL;
}
return &g_files[fd - MIN_START_FD];
}
struct File *VfsFileGet(void)
{
int i;
/* protected by g_fsMutex */
for (i = 0; i < NR_OPEN_DEFAULT; i++) {
if (g_files[i].fStatus == FILE_STATUS_NOT_USED) {
g_files[i].fStatus = FILE_STATUS_INITING;
return &g_files[i];
}
}
return NULL;
}
struct File *VfsFileGetSpec(int fd)
{
if ((fd < MIN_START_FD) || (fd >= CONFIG_NFILE_DESCRIPTORS)) {
return NULL;
}
if (g_files[fd - MIN_START_FD].fStatus == FILE_STATUS_NOT_USED) {
g_files[fd - MIN_START_FD].fStatus = FILE_STATUS_INITING;
return &g_files[fd - MIN_START_FD];
}
return NULL;
}
void VfsFilePut(struct File *file)
{
if (file == NULL) {
return;
}
file->fFlags = 0;
file->fFops = NULL;
file->fData = NULL;
file->fMp = NULL;
file->fOffset = 0;
file->fOwner = -1;
file->fullPath = NULL;
file->fStatus = FILE_STATUS_NOT_USED;
}