1 // Copyright (c) 2012 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_DEBUG_STACK_TRACE_H_ 6 #define BASE_DEBUG_STACK_TRACE_H_ 7 8 #include <iosfwd> 9 #include <string> 10 11 #include "base/base_export.h" 12 #include "build/build_config.h" 13 14 #if defined(OS_POSIX) 15 #include <unistd.h> 16 #endif 17 18 #if defined(OS_WIN) 19 struct _EXCEPTION_POINTERS; 20 #endif 21 22 namespace base { 23 namespace debug { 24 25 // Enables stack dump to console output on exception and signals. 26 // When enabled, the process will quit immediately. This is meant to be used in 27 // unit_tests only! This is not thread-safe: only call from main thread. 28 BASE_EXPORT bool EnableInProcessStackDumping(); 29 30 // A stacktrace can be helpful in debugging. For example, you can include a 31 // stacktrace member in a object (probably around #ifndef NDEBUG) so that you 32 // can later see where the given object was created from. 33 class BASE_EXPORT StackTrace { 34 public: 35 // Creates a stacktrace from the current location. 36 StackTrace(); 37 38 // Creates a stacktrace from an existing array of instruction 39 // pointers (such as returned by Addresses()). |count| will be 40 // trimmed to |kMaxTraces|. 41 StackTrace(const void* const* trace, size_t count); 42 43 #if defined(OS_WIN) 44 // Creates a stacktrace for an exception. 45 // Note: this function will throw an import not found (StackWalk64) exception 46 // on system without dbghelp 5.1. 47 StackTrace(_EXCEPTION_POINTERS* exception_pointers); 48 #endif 49 50 // Copying and assignment are allowed with the default functions. 51 52 ~StackTrace(); 53 54 // Gets an array of instruction pointer values. |*count| will be set to the 55 // number of elements in the returned array. 56 const void* const* Addresses(size_t* count) const; 57 58 // Prints a backtrace to stderr 59 void PrintBacktrace() const; 60 61 // Resolves backtrace to symbols and write to stream. 62 void OutputToStream(std::ostream* os) const; 63 64 // Resolves backtrace to symbols and returns as string. 65 std::string ToString() const; 66 67 private: 68 // From http://msdn.microsoft.com/en-us/library/bb204633.aspx, 69 // the sum of FramesToSkip and FramesToCapture must be less than 63, 70 // so set it to 62. Even if on POSIX it could be a larger value, it usually 71 // doesn't give much more information. 72 static const int kMaxTraces = 62; 73 74 void* trace_[kMaxTraces]; 75 76 // The number of valid frames in |trace_|. 77 size_t count_; 78 }; 79 80 namespace internal { 81 82 #if defined(OS_POSIX) && !defined(OS_ANDROID) 83 // POSIX doesn't define any async-signal safe function for converting 84 // an integer to ASCII. We'll have to define our own version. 85 // itoa_r() converts a (signed) integer to ASCII. It returns "buf", if the 86 // conversion was successful or NULL otherwise. It never writes more than "sz" 87 // bytes. Output will be truncated as needed, and a NUL character is always 88 // appended. 89 BASE_EXPORT char *itoa_r(intptr_t i, 90 char *buf, 91 size_t sz, 92 int base, 93 size_t padding); 94 #endif // defined(OS_POSIX) && !defined(OS_ANDROID) 95 96 } // namespace internal 97 98 } // namespace debug 99 } // namespace base 100 101 #endif // BASE_DEBUG_STACK_TRACE_H_ 102
