1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/ipc/chromium/src/base/tracked.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,128 @@
1.4 +// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
1.5 +// Use of this source code is governed by a BSD-style license that can be
1.6 +// found in the LICENSE file.
1.7 +
1.8 +//------------------------------------------------------------------------------
1.9 +// Tracked is the base class for all tracked objects. During construction, it
1.10 +// registers the fact that an instance was created, and at destruction time, it
1.11 +// records that event. The instance may be tagged with a name, which is refered
1.12 +// to as its Location. The Location is a file and line number, most
1.13 +// typically indicated where the object was constructed. In some cases, as the
1.14 +// object's significance is refined (for example, a Task object is augmented to
1.15 +// do additonal things), its Location may be redefined to that later location.
1.16 +
1.17 +// Tracking includes (for each instance) recording the birth thread, death
1.18 +// thread, and duration of life (from construction to destruction). All this
1.19 +// data is accumulated and filtered for review at about:objects.
1.20 +
1.21 +#ifndef BASE_TRACKED_H_
1.22 +#define BASE_TRACKED_H_
1.23 +
1.24 +#include <string>
1.25 +
1.26 +#include "base/time.h"
1.27 +
1.28 +#ifndef NDEBUG
1.29 +#ifndef TRACK_ALL_TASK_OBJECTS
1.30 +#define TRACK_ALL_TASK_OBJECTS
1.31 +#endif // TRACK_ALL_TASK_OBJECTS
1.32 +#endif // NDEBUG
1.33 +
1.34 +namespace tracked_objects {
1.35 +
1.36 +//------------------------------------------------------------------------------
1.37 +// Location provides basic info where of an object was constructed, or was
1.38 +// significantly brought to life.
1.39 +
1.40 +class Location {
1.41 + public:
1.42 + // Constructor should be called with a long-lived char*, such as __FILE__.
1.43 + // It assumes the provided value will persist as a global constant, and it
1.44 + // will not make a copy of it.
1.45 + Location(const char* function_name, const char* file_name, int line_number)
1.46 + : function_name_(function_name),
1.47 + file_name_(file_name),
1.48 + line_number_(line_number) { }
1.49 +
1.50 + // Provide a default constructor for easy of debugging.
1.51 + Location()
1.52 + : function_name_("Unknown"),
1.53 + file_name_("Unknown"),
1.54 + line_number_(-1) { }
1.55 +
1.56 + // Comparison operator for insertion into a std::map<> hash tables.
1.57 + // All we need is *some* (any) hashing distinction. Strings should already
1.58 + // be unique, so we don't bother with strcmp or such.
1.59 + // Use line number as the primary key (because it is fast, and usually gets us
1.60 + // a difference), and then pointers as secondary keys (just to get some
1.61 + // distinctions).
1.62 + bool operator < (const Location& other) const {
1.63 + if (line_number_ != other.line_number_)
1.64 + return line_number_ < other.line_number_;
1.65 + if (file_name_ != other.file_name_)
1.66 + return file_name_ < other.file_name_;
1.67 + return function_name_ < other.function_name_;
1.68 + }
1.69 +
1.70 + const char* function_name() const { return function_name_; }
1.71 + const char* file_name() const { return file_name_; }
1.72 + int line_number() const { return line_number_; }
1.73 +
1.74 + void Write(bool display_filename, bool display_function_name,
1.75 + std::string* output) const;
1.76 +
1.77 + // Write function_name_ in HTML with '<' and '>' properly encoded.
1.78 + void WriteFunctionName(std::string* output) const;
1.79 +
1.80 + private:
1.81 + const char* const function_name_;
1.82 + const char* const file_name_;
1.83 + const int line_number_;
1.84 +};
1.85 +
1.86 +
1.87 +//------------------------------------------------------------------------------
1.88 +// Define a macro to record the current source location.
1.89 +
1.90 +#define FROM_HERE tracked_objects::Location(__FUNCTION__, __FILE__, __LINE__)
1.91 +
1.92 +
1.93 +//------------------------------------------------------------------------------
1.94 +
1.95 +
1.96 +class Births;
1.97 +
1.98 +class Tracked {
1.99 + public:
1.100 + Tracked();
1.101 + virtual ~Tracked();
1.102 +
1.103 + // Used to record the FROM_HERE location of a caller.
1.104 + void SetBirthPlace(const Location& from_here);
1.105 +
1.106 + // When a task sits around a long time, such as in a timer, or object watcher,
1.107 + // this method should be called when the task becomes active, and its
1.108 + // significant lifetime begins (and its waiting to be woken up has passed).
1.109 + void ResetBirthTime();
1.110 +
1.111 + bool MissingBirthplace() const;
1.112 +
1.113 + private:
1.114 +#ifdef TRACK_ALL_TASK_OBJECTS
1.115 +
1.116 + // Pointer to instance were counts of objects with the same birth location
1.117 + // (on the same thread) are stored.
1.118 + Births* tracked_births_;
1.119 + // The time this object was constructed. If its life consisted of a long
1.120 + // waiting period, and then it became active, then this value is generally
1.121 + // reset before the object begins it active life.
1.122 + base::Time tracked_birth_time_;
1.123 +
1.124 +#endif // TRACK_ALL_TASK_OBJECTS
1.125 +
1.126 + DISALLOW_COPY_AND_ASSIGN(Tracked);
1.127 +};
1.128 +
1.129 +} // namespace tracked_objects
1.130 +
1.131 +#endif // BASE_TRACKED_H_
