1 // Copyright 2011 The Chromium Authors
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 PARTITION_ALLOC_PARTITION_ALLOC_BASE_POSIX_SAFE_STRERROR_H_
6 #define PARTITION_ALLOC_PARTITION_ALLOC_BASE_POSIX_SAFE_STRERROR_H_
7 
8 #include <cstddef>
9 #include <string>
10 
11 #include "partition_alloc/partition_alloc_base/component_export.h"
12 
13 namespace partition_alloc::internal::base {
14 
15 // BEFORE using anything from this file, first look at PLOG and friends in
16 // logging.h and use them instead if applicable.
17 //
18 // This file declares safe, portable alternatives to the POSIX strerror()
19 // function. strerror() is inherently unsafe in multi-threaded apps and should
20 // never be used. Doing so can cause crashes. Additionally, the thread-safe
21 // alternative strerror_r varies in semantics across platforms. Use these
22 // functions instead.
23 
24 // Thread-safe strerror function with dependable semantics that never fails.
25 // It will write the string form of error "err" to buffer buf of length len.
26 // If there is an error calling the OS's strerror_r() function then a message to
27 // that effect will be printed into buf, truncating if necessary. The final
28 // result is always null-terminated. The value of errno is never changed.
29 //
30 // Use this instead of strerror_r().
31 PA_COMPONENT_EXPORT(PARTITION_ALLOC_BASE)
32 void safe_strerror_r(int err, char* buf, size_t len);
33 
34 // Calls safe_strerror_r with a buffer of suitable size and returns the result
35 // in a C++ string.
36 //
37 // Use this instead of strerror(). Note though that safe_strerror_r will be
38 // more robust in the case of heap corruption errors, since it doesn't need to
39 // allocate a string.
40 PA_COMPONENT_EXPORT(PARTITION_ALLOC_BASE) std::string safe_strerror(int err);
41 
42 }  // namespace partition_alloc::internal::base
43 
44 #endif  // PARTITION_ALLOC_PARTITION_ALLOC_BASE_POSIX_SAFE_STRERROR_H_
45