base/safe_strerror_posix.h

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