| // Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef CHROME_BROWSER_DRIVE_EVENT_LOGGER_H_ |
| #define CHROME_BROWSER_DRIVE_EVENT_LOGGER_H_ |
| |
| #include <deque> |
| #include <string> |
| #include <vector> |
| |
| #include "base/basictypes.h" |
| #include "base/compiler_specific.h" |
| #include "base/logging.h" |
| #include "base/synchronization/lock.h" |
| #include "base/time/time.h" |
| |
| namespace drive { |
| |
| // The default history size used by EventLogger. |
| const int kDefaultHistorySize = 1000; |
| |
| // EventLogger is used to collect and expose text messages for diagnosing |
| // behaviors of Google APIs stuff. For instance, the collected messages are |
| // exposed to chrome:drive-internals. |
| class EventLogger { |
| public: |
| // Represents a single event log. |
| struct Event { |
| Event(int id, logging::LogSeverity severity, const std::string& what); |
| int id; // Monotonically increasing ID starting from 0. |
| logging::LogSeverity severity; // Severity of the event. |
| base::Time when; // When the event occurred. |
| std::string what; // What happened. |
| }; |
| |
| // Creates an event logger that keeps the latest kDefaultHistorySize events. |
| EventLogger(); |
| ~EventLogger(); |
| |
| // Logs a message and its severity. |
| // Can be called from any thread as long as the object is alive. |
| void LogRawString(logging::LogSeverity severity, const std::string& what); |
| |
| // Logs a message with formatting. |
| // Can be called from any thread as long as the object is alive. |
| void Log(logging::LogSeverity severity, const char* format, ...) |
| PRINTF_FORMAT(3, 4); |
| |
| // Sets the history size. The existing history is cleared. |
| // Can be called from any thread as long as the object is alive. |
| void SetHistorySize(size_t history_size); |
| |
| // Gets the list of latest events (the oldest event comes first). |
| // Can be called from any thread as long as the object is alive. |
| std::vector<Event> GetHistory(); |
| |
| private: |
| std::deque<Event> history_; // guarded by lock_. |
| size_t history_size_; // guarded by lock_. |
| int next_event_id_; // guarded by lock_. |
| base::Lock lock_; |
| |
| DISALLOW_COPY_AND_ASSIGN(EventLogger); |
| }; |
| |
| } // namespace drive |
| |
| #endif // CHROME_BROWSER_DRIVE_EVENT_LOGGER_H_ |