base/safe_strerror_posix.h

   1 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef BASE_SAFE_STRERROR_POSIX_H_
   6 #define BASE_SAFE_STRERROR_POSIX_H_
   7 #pragma once
   8
   9 #include <string>
  10
  11 #include "base/base_export.h"
  12
  13 // BEFORE using anything from this file, first look at PLOG and friends in
  14 // logging.h and use them instead if applicable.
  15 //
  16 // This file declares safe, portable alternatives to the POSIX strerror()
  17 // function. strerror() is inherently unsafe in multi-threaded apps and should
  18 // never be used. Doing so can cause crashes. Additionally, the thread-safe
  19 // alternative strerror_r varies in semantics across platforms. Use these
  20 // functions instead.
  21
  22 // Thread-safe strerror function with dependable semantics that never fails.
  23 // It will write the string form of error "err" to buffer buf of length len.
  24 // If there is an error calling the OS's strerror_r() function then a message to
  25 // that effect will be printed into buf, truncating if necessary. The final
  26 // result is always null-terminated. The value of errno is never changed.
  27 //
  28 // Use this instead of strerror_r().
  29 BASE_EXPORT void safe_strerror_r(int err, char *buf, size_t len);
  30
  31 // Calls safe_strerror_r with a buffer of suitable size and returns the result
  32 // in a C++ string.
  33 //
  34 // Use this instead of strerror(). Note though that safe_strerror_r will be
  35 // more robust in the case of heap corruption errors, since it doesn't need to
  36 // allocate a string.
  37 BASE_EXPORT std::string safe_strerror(int err);
  38
  39 #endif  // BASE_SAFE_STRERROR_POSIX_H_