1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include "os.h"
18
19#include <sys/types.h>
20#include <sys/stat.h>
21#include <fcntl.h>
22#include <cstddef>
23#include <memory>
24
25#include "base/logging.h"
26#include "base/unix_file/fd_file.h"
27
28namespace art {
29
30File* OS::OpenFileForReading(const char* name) {
31  return OpenFileWithFlags(name, O_RDONLY);
32}
33
34File* OS::OpenFileReadWrite(const char* name) {
35  return OpenFileWithFlags(name, O_RDWR);
36}
37
38static File* CreateEmptyFile(const char* name, int extra_flags) {
39  // In case the file exists, unlink it so we get a new file. This is necessary as the previous
40  // file may be in use and must not be changed.
41  unlink(name);
42
43  return OS::OpenFileWithFlags(name, O_CREAT | extra_flags);
44}
45
46File* OS::CreateEmptyFile(const char* name) {
47  return art::CreateEmptyFile(name, O_RDWR | O_TRUNC);
48}
49
50File* OS::CreateEmptyFileWriteOnly(const char* name) {
51  return art::CreateEmptyFile(name, O_WRONLY | O_TRUNC | O_NOFOLLOW | O_CLOEXEC);
52}
53
54File* OS::OpenFileWithFlags(const char* name, int flags) {
55  CHECK(name != nullptr);
56  std::unique_ptr<File> file(new File);
57  if (!file->Open(name, flags, 0666)) {
58    return nullptr;
59  }
60  return file.release();
61}
62
63bool OS::FileExists(const char* name) {
64  struct stat st;
65  if (stat(name, &st) == 0) {
66    return S_ISREG(st.st_mode);  // TODO: Deal with symlinks?
67  } else {
68    return false;
69  }
70}
71
72bool OS::DirectoryExists(const char* name) {
73  struct stat st;
74  if (stat(name, &st) == 0) {
75    return S_ISDIR(st.st_mode);  // TODO: Deal with symlinks?
76  } else {
77    return false;
78  }
79}
80
81}  // namespace art
82