xref: /kernel/liteos_m/components/fs/vfs/vfs_files.c (revision 3d8536b4)
1/*
2 * Copyright (c) 2022-2022 Huawei Device Co., Ltd. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without modification,
5 * are permitted provided that the following conditions are met:
6 *
7 * 1. Redistributions of source code must retain the above copyright notice, this list of
8 *    conditions and the following disclaimer.
9 *
10 * 2. Redistributions in binary form must reproduce the above copyright notice, this list
11 *    of conditions and the following disclaimer in the documentation and/or other materials
12 *    provided with the distribution.
13 *
14 * 3. Neither the name of the copyright holder nor the names of its contributors may be used
15 *    to endorse or promote products derived from this software without specific prior written
16 *    permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
20 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
21 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
22 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
23 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
24 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
25 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
26 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
27 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
28 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30#include "vfs_files.h"
31#include "errno.h"
32#include "stdio.h"
33#include "stdlib.h"
34#include "string.h"
35#include "los_config.h"
36#include "vfs_config.h"
37#include "vfs_mount.h"
38#include "vfs_operations.h"
39
40static struct File g_files[NR_OPEN_DEFAULT];
41
42int FileToFd(const struct File *file)
43{
44    if (file == NULL) {
45        return (int)LOS_NOK;
46    }
47    return file - g_files + MIN_START_FD;
48}
49
50struct File *FdToFile(int fd)
51{
52    if ((fd < MIN_START_FD) || (fd >= CONFIG_NFILE_DESCRIPTORS)) {
53        return NULL;
54    }
55    return &g_files[fd - MIN_START_FD];
56}
57
58struct File *VfsFileGet(void)
59{
60    int i;
61    /* protected by g_fsMutex */
62    for (i = 0; i < NR_OPEN_DEFAULT; i++) {
63        if (g_files[i].fStatus == FILE_STATUS_NOT_USED) {
64            g_files[i].fStatus = FILE_STATUS_INITING;
65            return &g_files[i];
66        }
67    }
68
69    return NULL;
70}
71
72struct File *VfsFileGetSpec(int fd)
73{
74    if ((fd < MIN_START_FD) || (fd >= CONFIG_NFILE_DESCRIPTORS)) {
75        return NULL;
76    }
77    if (g_files[fd - MIN_START_FD].fStatus == FILE_STATUS_NOT_USED) {
78        g_files[fd - MIN_START_FD].fStatus = FILE_STATUS_INITING;
79        return &g_files[fd - MIN_START_FD];
80    }
81
82    return NULL;
83}
84
85void VfsFilePut(struct File *file)
86{
87    if (file == NULL) {
88        return;
89    }
90    file->fFlags = 0;
91    file->fFops = NULL;
92    file->fData = NULL;
93    file->fMp = NULL;
94    file->fOffset = 0;
95    file->fOwner = -1;
96    file->fullPath = NULL;
97    file->fStatus = FILE_STATUS_NOT_USED;
98}
99