| // Copyright 2022 The Cobalt Authors. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #ifndef COBALT_WATCHDOG_WATCHDOG_H_ |
| #define COBALT_WATCHDOG_WATCHDOG_H_ |
| |
| #include <memory> |
| #include <string> |
| #include <unordered_map> |
| #include <vector> |
| |
| #include "base/values.h" |
| #include "cobalt/base/application_state.h" |
| #include "cobalt/persistent_storage/persistent_settings.h" |
| #include "cobalt/watchdog/singleton.h" |
| #include "starboard/common/atomic.h" |
| #include "starboard/common/condition_variable.h" |
| #include "starboard/common/mutex.h" |
| #include "starboard/thread.h" |
| #include "starboard/time.h" |
| |
| namespace cobalt { |
| namespace watchdog { |
| |
| // Client to monitor |
| typedef struct Client { |
| std::string name; |
| std::string description; |
| // List of strings optionally provided with each Ping. |
| base::Value ping_infos; |
| // Application state to continue monitoring client up to. Inclusive. |
| base::ApplicationState monitor_state; |
| // Maximum number of microseconds allowed between pings before triggering a |
| // Watchdog violation. |
| int64_t time_interval_microseconds; |
| // Number of microseconds to initially wait before Watchdog violations can be |
| // triggered. Reapplies after client resumes from idle state due to |
| // application state changes. |
| int64_t time_wait_microseconds; |
| // Epoch time when client was registered. |
| int64_t time_registered_microseconds; |
| // Monotonically increasing timestamp when client was registered. Used as the |
| // start value for time wait calculations. |
| SbTimeMonotonic time_registered_monotonic_microseconds; |
| // Epoch time when client was last pinged. Set by Ping() and Register() when |
| // in PING replace mode or set initially by Register(). |
| int64_t time_last_pinged_microseconds; |
| // Monotonically increasing timestamp when client was last updated. Set by |
| // Ping() and Register() when in PING replace mode or set initially by |
| // Register(). Also reset by Monitor() when in idle states or when a |
| // violation occurs. Prevents excessive violations as they must occur |
| // time_interval_microseconds apart rather than on each monitor loop. Used as |
| // the start value for time interval calculations. |
| SbTimeMonotonic time_last_updated_monotonic_microseconds; |
| } Client; |
| |
| // Register behavior with previously registered clients of the same name. |
| enum Replace { |
| NONE = 0, |
| PING = 1, |
| ALL = 2, |
| }; |
| |
| class Watchdog : public Singleton<Watchdog> { |
| public: |
| bool Initialize(persistent_storage::PersistentSettings* persistent_settings); |
| // Directly used for testing only. |
| bool InitializeCustom( |
| persistent_storage::PersistentSettings* persistent_settings, |
| std::string watchdog_file_name, int64_t watchdog_monitor_frequency); |
| bool InitializeStub(); |
| void Uninitialize(); |
| std::string GetWatchdogFilePath(); |
| std::vector<std::string> GetWatchdogViolationClientNames(); |
| void UpdateState(base::ApplicationState state); |
| bool Register(std::string name, std::string description, |
| base::ApplicationState monitor_state, |
| int64_t time_interval_microseconds, |
| int64_t time_wait_microseconds = 0, Replace replace = NONE); |
| bool Unregister(const std::string& name, bool lock = true); |
| bool Ping(const std::string& name); |
| bool Ping(const std::string& name, const std::string& info); |
| std::string GetWatchdogViolations( |
| const std::vector<std::string>& clients = {}, bool clear = true); |
| bool GetPersistentSettingWatchdogEnable(); |
| void SetPersistentSettingWatchdogEnable(bool enable_watchdog); |
| bool GetPersistentSettingWatchdogCrash(); |
| void SetPersistentSettingWatchdogCrash(bool can_trigger_crash); |
| |
| #if defined(_DEBUG) |
| // Sleeps threads based off of environment variables for Watchdog debugging. |
| void MaybeInjectDebugDelay(const std::string& name); |
| #endif // defined(_DEBUG) |
| |
| private: |
| void WriteWatchdogViolations(); |
| std::string ReadViolationFile(const char* file_path); |
| static void* Monitor(void* context); |
| static void UpdateViolationsMap(void* context, Client* client, |
| SbTimeMonotonic time_delta); |
| static void InitializeViolationsMap(void* context); |
| static void EvictWatchdogViolation(void* context); |
| static void MaybeWriteWatchdogViolations(void* context); |
| static void MaybeTriggerCrash(void* context); |
| |
| // The Watchdog violations json filename. |
| std::string watchdog_file_name_; |
| // The Watchdog violations json filepath. |
| std::string watchdog_file_path_; |
| // Access to persistent settings. |
| persistent_storage::PersistentSettings* persistent_settings_; |
| // Flag to disable Watchdog. When disabled, Watchdog behaves like a stub |
| // except that persistent settings can still be get/set. |
| bool is_disabled_; |
| // Creates a lock which ensures that each loop of monitor is atomic in that |
| // modifications to is_monitoring_, state_, and most importantly to the |
| // dictionaries containing Watchdog clients, client_map_ and violations_map_, |
| // only occur in between loops of monitor. API functions like Register(), |
| // Unregister(), Ping(), and GetWatchdogViolations() will be called by |
| // various threads and interact with these class variables. |
| starboard::Mutex mutex_; |
| // Tracks application state. |
| base::ApplicationState state_ = base::kApplicationStateStarted; |
| // Flag to trigger Watchdog violations writes to persistent storage. |
| bool pending_write_; |
| // Monotonically increasing timestamp when Watchdog violations were last |
| // written to persistent storage. 0 indicates that it has never been written. |
| SbTimeMonotonic time_last_written_microseconds_ = 0; |
| // Number of microseconds between writes. |
| int64_t write_wait_time_microseconds_; |
| // Dictionary of registered Watchdog clients. |
| std::unordered_map<std::string, std::unique_ptr<Client>> client_map_; |
| // Dictionary of lists of Watchdog violations represented as dictionaries. |
| std::unique_ptr<base::Value> violations_map_; |
| // Number of violations in violations_map_; |
| int violations_count_; |
| // Monitor thread. |
| SbThread watchdog_thread_; |
| // Flag to stop monitor thread. |
| starboard::atomic_bool is_monitoring_; |
| // Conditional Variable to wait and shutdown monitor thread. |
| starboard::ConditionVariable monitor_wait_ = |
| starboard::ConditionVariable(mutex_); |
| // The frequency in microseconds of monitor loops. |
| int64_t watchdog_monitor_frequency_; |
| |
| #if defined(_DEBUG) |
| starboard::Mutex delay_mutex_; |
| // Name of the client to inject a delay for. |
| std::string delay_name_ = ""; |
| // Monotonically increasing timestamp when a delay was last injected. 0 |
| // indicates that it has never been injected. |
| SbTimeMonotonic time_last_delayed_microseconds_ = 0; |
| // Number of microseconds between delays. |
| int64_t delay_wait_time_microseconds_ = 0; |
| // Number of microseconds to delay. |
| int64_t delay_sleep_time_microseconds_ = 0; |
| #endif |
| }; |
| |
| } // namespace watchdog |
| } // namespace cobalt |
| |
| #endif // COBALT_WATCHDOG_WATCHDOG_H_ |