1 /*
2  * Copyright (C) 2009 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 #ifndef ART_LIBARTBASE_BASE_OS_H_
18 #define ART_LIBARTBASE_BASE_OS_H_
19 
20 #include <stdint.h>
21 
22 namespace unix_file {
23 class FdFile;
24 }  // namespace unix_file
25 
26 namespace art {
27 
28 typedef ::unix_file::FdFile File;
29 
30 // Interface to the underlying OS platform.
31 
32 class OS {
33  public:
34   // Open an existing file with read only access.
35   static File* OpenFileForReading(const char* name);
36 
37   // Open an existing file with read/write access.
38   static File* OpenFileReadWrite(const char* name);
39 
40   // Create an empty file with read/write access. This is a *new* file, that is, if the file
41   // already exists, it is *not* overwritten, but unlinked, and a new inode will be used.
42   static File* CreateEmptyFile(const char* name);
43 
44   // Create an empty file with write access. This is a *new* file, that is, if the file
45   // already exists, it is *not* overwritten, but unlinked, and a new inode will be used.
46   static File* CreateEmptyFileWriteOnly(const char* name);
47 
48   // Open a file with the specified open(2) flags.
49   static File* OpenFileWithFlags(const char* name, int flags, bool auto_flush = true);
50 
51   // Check if a file exists.
52   static bool FileExists(const char* name, bool check_file_type = true);
53 
54   // Check if a directory exists.
55   static bool DirectoryExists(const char* name);
56 
57   // Get the size of a file (or -1 if it does not exist).
58   static int64_t GetFileSizeBytes(const char* name);
59 };
60 
61 }  // namespace art
62 
63 #endif  // ART_LIBARTBASE_BASE_OS_H_
64