blob: b31d5e410233df633381269d5997bdc962947fe1 [file] [log] [blame]
// Copyright 2015 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.
#include <map>
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/threading/thread_checker.h"
#include "tools/battor_agent/battor_connection.h"
#include "tools/battor_agent/battor_error.h"
namespace battor {
// A BattOrAgent is a class used to asynchronously communicate with a BattOr for
// the purpose of collecting power samples. A BattOr is an external USB device
// that's capable of recording accurate, high-frequency (2000Hz) power samples.
// The serial connection is automatically opened when the first command
// (e.g. StartTracing(), StopTracing(), etc.) is issued, and automatically
// closed when either StopTracing() or the destructor is called. For Telemetry,
// this means that the connection must be reinitialized for every command that's
// issued because a new BattOrAgent is constructed. For Chromium, we use the
// same BattOrAgent for multiple commands and thus avoid having to reinitialize
// the serial connection.
// This class is NOT thread safe. Any interactions with this class that involve
// IO (i.e. any interactions that require a callback) must be done from the
// same IO thread, which must also have a running MessageLoop.
class BattOrAgent : public BattOrConnection::Listener,
public base::SupportsWeakPtr<BattOrAgent> {
// The listener interface that must be implemented in order to interact with
// the BattOrAgent.
class Listener {
virtual void OnStartTracingComplete(BattOrError error) = 0;
virtual void OnStopTracingComplete(const std::string& trace,
BattOrError error) = 0;
virtual void OnRecordClockSyncMarkerComplete(BattOrError error) = 0;
const std::string& path,
Listener* listener,
scoped_refptr<base::SingleThreadTaskRunner> file_thread_task_runner,
scoped_refptr<base::SingleThreadTaskRunner> ui_thread_task_runner);
virtual ~BattOrAgent();
void StartTracing();
void StopTracing();
void RecordClockSyncMarker(const std::string& marker);
// Returns whether the BattOr is able to record clock sync markers in its own
// trace log.
static bool SupportsExplicitClockSync() { return true; }
// BattOrConnection::Listener implementation.
void OnConnectionOpened(bool success) override;
void OnBytesSent(bool success) override;
void OnMessageRead(bool success,
BattOrMessageType type,
scoped_ptr<std::vector<char>> bytes) override;
// The connection that knows how to communicate with the BattOr in terms of
// protocol primitives. This is protected so that it can be replaced with a
// fake in testing.
scoped_ptr<BattOrConnection> connection_;
enum class Command {
enum class Action {
// Actions required to connect to a BattOr.
// Actions required for starting tracing.
// Actions required for stopping tracing.
// Actions required for recording a clock sync marker.
// Performs an action.
void PerformAction(Action action);
// Performs an action after a delay.
void PerformDelayedAction(Action action, base::TimeDelta delay);
// Requests a connection to the BattOr.
void BeginConnect();
// Sends a control message over the connection.
void SendControlMessage(BattOrControlMessageType type,
uint16_t param1,
uint16_t param2);
// Completes the command with the specified error.
void CompleteCommand(BattOrError error);
// Returns a formatted version of samples_ with timestamps and real units.
std::string SamplesToString();
// The listener that handles the commands' results. It must outlive the agent.
Listener* listener_;
// The last action executed by the agent. This should only be updated in
// PerformAction().
Action last_action_;
// The tracing command currently being executed by the agent.
Command command_;
// A map from the sample number (including samples from the calibration frame)
// to the ID of the clock sync marker that is associated with that sample
// number. If we ever have to store a large number of these, consider using an
// unordered map.
std::map<uint32_t, std::string> clock_sync_markers_;
// The clock sync marker being recorded (if we're currently recording one).
std::string pending_clock_sync_marker_;
// The time at which the last clock sync marker was recorded.
base::TimeTicks last_clock_sync_time_;
// Checker to make sure that this is only ever called on the IO thread.
base::ThreadChecker thread_checker_;
// The BattOr's EEPROM (which is required for calibration).
scoped_ptr<BattOrEEPROM> battor_eeprom_;
// The first frame (required for calibration).
std::vector<RawBattOrSample> calibration_frame_;
// The actual data samples recorded.
std::vector<RawBattOrSample> samples_;
// The expected sequence number of the next frame. We use this to ensure that
// we receive frames in order.
uint32_t next_sequence_number_;
// The number of times that we've attempted to read the last message.
uint8_t num_read_attempts_;
} // namespace battor