1 /*
2 * Copyright (c) 2023 Huawei Device Co., Ltd.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15
16 #include "file_utils.h"
17
18 #include <sys/types.h>
19 #include <unistd.h>
20
21 #include "dfs_error.h"
22 #include "utils_log.h"
23
24 namespace OHOS {
25 namespace FileManagement {
ReadFile(int fd,off_t offset,size_t size,void * data)26 int64_t FileUtils::ReadFile(int fd, off_t offset, size_t size, void *data)
27 {
28 if ((fd < 0) || (offset < 0) || (size < 0) || (data == nullptr)) {
29 LOGE("invalid params, fd %{public}d, offset %{public}d, size %{public}zu, or buf is null", fd,
30 static_cast<int>(offset), size);
31 return -1;
32 }
33
34 off_t err = lseek(fd, offset, SEEK_SET);
35 if (err < 0) {
36 return -errno;
37 }
38
39 size_t readLen = 0;
40 while (readLen < size) {
41 ssize_t ret = read(fd, data, size - readLen);
42 if (ret < 0) {
43 LOGE("read failed, errno %{public}d, fd=%{public}d", errno, fd);
44 return ret;
45 } else if (ret == 0) {
46 break;
47 }
48 readLen += ret;
49 }
50
51 return readLen;
52 }
53
WriteFile(int fd,const void * data,off_t offset,size_t size)54 int64_t FileUtils::WriteFile(int fd, const void *data, off_t offset, size_t size)
55 {
56 if ((fd < 0) || (offset < 0) || (size < 0) || (data == nullptr)) {
57 LOGE("invalid params, fd %{public}d, offset %{public}d, size %{public}zu, or buf is null", fd,
58 static_cast<int>(offset), size);
59 return -1;
60 }
61
62 off_t err = lseek(fd, offset, SEEK_SET);
63 if (err < 0) {
64 return -errno;
65 }
66
67 size_t writeLen = 0;
68 while (writeLen < size) {
69 ssize_t ret = write(fd, data, size - writeLen);
70 if (ret <= 0) {
71 LOGE("write failed, errno %{public}d, fd=%{public}d", errno, fd);
72 return ret;
73 }
74 writeLen += ret;
75 }
76
77 return writeLen;
78 }
79 } // namespace FileManagement
80 } // namespace OHOS
81