• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright (C) 2012 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 __CUTILS_FS_H
18 #define __CUTILS_FS_H
19 
20 #include <sys/types.h>
21 
22 /*
23  * TEMP_FAILURE_RETRY is defined by some, but not all, versions of
24  * <unistd.h>. (Alas, it is not as standard as we'd hoped!) So, if it's
25  * not already defined, then define it here.
26  */
27 #ifndef TEMP_FAILURE_RETRY
28 /* Used to retry syscalls that can return EINTR. */
29 #define TEMP_FAILURE_RETRY(exp) ({         \
30     typeof (exp) _rc;                      \
31     do {                                   \
32         _rc = (exp);                       \
33     } while (_rc == -1 && errno == EINTR); \
34     _rc; })
35 #endif
36 
37 #ifdef __cplusplus
38 extern "C" {
39 #endif
40 
41 /*
42  * Ensure that directory exists with given mode and owners.
43  */
44 extern int fs_prepare_dir(const char* path, mode_t mode, uid_t uid, gid_t gid);
45 
46 /*
47  * Read single plaintext integer from given file, correctly handling files
48  * partially written with fs_write_atomic_int().
49  */
50 extern int fs_read_atomic_int(const char* path, int* value);
51 
52 /*
53  * Write single plaintext integer to given file, creating backup while
54  * in progress.
55  */
56 extern int fs_write_atomic_int(const char* path, int value);
57 
58 /*
59  * Ensure that all directories along given path exist, creating parent
60  * directories as needed.  Validates that given path is absolute and that
61  * it contains no relative "." or ".." paths or symlinks.  Last path segment
62  * is treated as filename and ignored, unless the path ends with "/".
63  */
64 extern int fs_mkdirs(const char* path, mode_t mode);
65 
66 #ifdef __cplusplus
67 }
68 #endif
69 
70 #endif /* __CUTILS_FS_H */
71