1c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Copyright (c) 2009 The Chromium Authors. All rights reserved. 2c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use of this source code is governed by a BSD-style license that can be 3c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// found in the LICENSE file. 4c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 5c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#ifndef BASE_SAFE_STRERROR_POSIX_H_ 6c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#define BASE_SAFE_STRERROR_POSIX_H_ 73345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#pragma once 8c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 9c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#include <string> 10c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 11c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// BEFORE using anything from this file, first look at PLOG and friends in 12c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// logging.h and use them instead if applicable. 13c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// 14c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// This file declares safe, portable alternatives to the POSIX strerror() 15c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// function. strerror() is inherently unsafe in multi-threaded apps and should 16c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// never be used. Doing so can cause crashes. Additionally, the thread-safe 17c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// alternative strerror_r varies in semantics across platforms. Use these 18c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// functions instead. 19c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 20c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Thread-safe strerror function with dependable semantics that never fails. 21c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// It will write the string form of error "err" to buffer buf of length len. 22c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// If there is an error calling the OS's strerror_r() function then a message to 23c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// that effect will be printed into buf, truncating if necessary. The final 24c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// result is always null-terminated. The value of errno is never changed. 25c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// 26c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use this instead of strerror_r(). 27c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottvoid safe_strerror_r(int err, char *buf, size_t len); 28c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 29c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Calls safe_strerror_r with a buffer of suitable size and returns the result 30c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// in a C++ string. 31c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// 32c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// Use this instead of strerror(). Note though that safe_strerror_r will be 33c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// more robust in the case of heap corruption errors, since it doesn't need to 34c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott// allocate a string. 35c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scottstd::string safe_strerror(int err); 36c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott 37c7f5f8508d98d5952d42ed7648c2a8f30a4da156Patrick Scott#endif // BASE_SAFE_STRERROR_POSIX_H_ 38