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