1 /* 2 * Copyright (C) 2018 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 INCLUDE_PERFETTO_EXT_BASE_FILE_UTILS_H_ 18 #define INCLUDE_PERFETTO_EXT_BASE_FILE_UTILS_H_ 19 20 #include <fcntl.h> // For mode_t & O_RDONLY/RDWR. Exists also on Windows. 21 #include <stddef.h> 22 23 #include <string> 24 25 #include "perfetto/base/build_config.h" 26 #include "perfetto/base/export.h" 27 #include "perfetto/ext/base/scoped_file.h" 28 #include "perfetto/ext/base/utils.h" 29 30 namespace perfetto { 31 namespace base { 32 33 #if PERFETTO_BUILDFLAG(PERFETTO_OS_WIN) 34 using FileOpenMode = int; 35 #else 36 using FileOpenMode = mode_t; 37 #endif 38 39 constexpr FileOpenMode kFileModeInvalid = static_cast<FileOpenMode>(-1); 40 41 bool ReadPlatformHandle(PlatformHandle, std::string* out); 42 bool ReadFileDescriptor(int fd, std::string* out); 43 bool ReadFileStream(FILE* f, std::string* out); 44 bool ReadFile(const std::string& path, std::string* out); 45 46 // A wrapper around read(2). It deals with Linux vs Windows includes. It also 47 // deals with handling EINTR. Has the same semantics of UNIX's read(2). 48 ssize_t Read(int fd, void* dst, size_t dst_size); 49 50 // Call write until all data is written or an error is detected. 51 // 52 // man 2 write: 53 // If a write() is interrupted by a signal handler before any bytes are 54 // written, then the call fails with the error EINTR; if it is 55 // interrupted after at least one byte has been written, the call 56 // succeeds, and returns the number of bytes written. 57 ssize_t WriteAll(int fd, const void* buf, size_t count); 58 59 ssize_t WriteAllHandle(PlatformHandle, const void* buf, size_t count); 60 61 ScopedFile OpenFile(const std::string& path, 62 int flags, 63 FileOpenMode = kFileModeInvalid); 64 65 // This is an alias for close(). It's to avoid leaking Windows.h in headers. 66 // Exported because ScopedFile is used in the /include/ext API by Chromium 67 // component builds. 68 int PERFETTO_EXPORT CloseFile(int fd); 69 70 bool FlushFile(int fd); 71 72 // Returns true if mkdir succeeds, false if it fails (see errno in that case). 73 bool Mkdir(const std::string& path); 74 75 // Calls rmdir() on UNIX, _rmdir() on Windows. 76 bool Rmdir(const std::string& path); 77 78 // Wrapper around access(path, F_OK). 79 bool FileExists(const std::string& path); 80 81 } // namespace base 82 } // namespace perfetto 83 84 #endif // INCLUDE_PERFETTO_EXT_BASE_FILE_UTILS_H_ 85