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 #include <unistd.h> 22 23 /* 24 * TEMP_FAILURE_RETRY is defined by some, but not all, versions of 25 * <unistd.h>. (Alas, it is not as standard as we'd hoped!) So, if it's 26 * not already defined, then define it here. 27 */ 28 #ifndef TEMP_FAILURE_RETRY 29 /* Used to retry syscalls that can return EINTR. */ 30 #define TEMP_FAILURE_RETRY(exp) ({ \ 31 typeof (exp) _rc; \ 32 do { \ 33 _rc = (exp); \ 34 } while (_rc == -1 && errno == EINTR); \ 35 _rc; }) 36 #endif 37 38 #ifdef __cplusplus 39 extern "C" { 40 #endif 41 42 /* 43 * Ensure that directory exists with given mode and owners. 44 */ 45 extern int fs_prepare_dir(const char* path, mode_t mode, uid_t uid, gid_t gid); 46 47 /* 48 * Read single plaintext integer from given file, correctly handling files 49 * partially written with fs_write_atomic_int(). 50 */ 51 extern int fs_read_atomic_int(const char* path, int* value); 52 53 /* 54 * Write single plaintext integer to given file, creating backup while 55 * in progress. 56 */ 57 extern int fs_write_atomic_int(const char* path, int value); 58 59 /* 60 * Ensure that all directories along given path exist, creating parent 61 * directories as needed. Validates that given path is absolute and that 62 * it contains no relative "." or ".." paths or symlinks. Last path segment 63 * is treated as filename and ignored, unless the path ends with "/". 64 */ 65 extern int fs_mkdirs(const char* path, mode_t mode); 66 67 #ifdef __cplusplus 68 } 69 #endif 70 71 #endif /* __CUTILS_FS_H */ 72