Trace.h

//
//  Created by Ryan Huffman on 2016-12-14
//  Copyright 2013-2016 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//
 
#pragma once
#ifndef hifi_Trace_h
#define hifi_Trace_h
 
#include <cstdint>
#include <mutex>
 
#include <QtCore/QString>
#include <QtCore/QVariantMap>
#include <QtCore/QHash>
#include <QtCore/QSet>
#include <QtCore/QLoggingCategory>
 
#include "DependencyManager.h"
 
namespace tracing {
 
bool enabled();
 
using TraceTimestamp = uint64_t;
 
enum EventType : char {
    DurationBegin = 'B',
    DurationEnd = 'E',
 
    Complete = 'X',
    Instant = 'i',
    Counter = 'C',
 
    AsyncNestableStart = 'b',
    AsyncNestableInstant = 'n',
    AsyncNestableEnd = 'e',
 
    FlowStart = 's',
    FlowStep = 't',
    FlowEnd = 'f',
 
    Sample = 'P',
 
    ObjectCreated = 'N',
    ObjectSnapshot = 'O',
    ObjectDestroyed = 'D',
 
    Metadata = 'M',
 
    MemoryDumpGlobal = 'V',
    MemoryDumpProcess = 'v',
 
    Mark = 'R',
 
    ClockSync = 'c',
 
    ContextEnter = '(',
    ContextLeave = ')'
};
 
struct TraceEvent {
    QString id;
    QString name;
    EventType type;
    qint64 timestamp;
    qint64 processID;
    qint64 threadID;
    const QLoggingCategory& category;
    QVariantMap args;
    QVariantMap extra;
 
    void writeJson(QTextStream& out) const;
};
 
class Tracer : public Dependency {
public:
    static int64_t now();
    void traceEvent(const QLoggingCategory& category, 
        const QString& name, EventType type,
        const QString& id = "", 
        const QVariantMap& args = QVariantMap(), const QVariantMap& extra = QVariantMap());
 
    void traceEvent(const QLoggingCategory& category, 
        const QString& name, EventType type,
        int64_t timestamp,
        const QString& id = "", 
        const QVariantMap& args = QVariantMap(), const QVariantMap& extra = QVariantMap());
 
    void startTracing();
    void stopTracing();
    void serialize(const QString& file);
    bool isEnabled() const { return _enabled; }
 
private:
    void traceEvent(const QLoggingCategory& category, 
        const QString& name, EventType type,
        qint64 timestamp, qint64 processID, qint64 threadID,
        const QString& id = "",
        const QVariantMap& args = QVariantMap(), const QVariantMap& extra = QVariantMap());
 
    bool _enabled { false };
    std::list<TraceEvent> _events;
    std::list<TraceEvent> _metadataEvents;
    std::mutex _eventsMutex;
};
 
inline void traceEvent(const QLoggingCategory& category, int64_t timestamp, const QString& name, EventType type, const QString& id = "", const QVariantMap& args = {}, const QVariantMap& extra = {}) {
    if (!DependencyManager::isSet<Tracer>()) {
        return;
    }
    const auto& tracer = DependencyManager::get<Tracer>();
    if (tracer) {
        tracer->traceEvent(category, name, type, timestamp, id, args, extra);
    }
}
 
inline void traceEvent(const QLoggingCategory& category, const QString& name, EventType type, const QString& id = "", const QVariantMap& args = {}, const QVariantMap& extra = {}) {
    if (!DependencyManager::isSet<Tracer>()) {
        return;
    }
    const auto& tracer = DependencyManager::get<Tracer>();
    if (tracer) {
        tracer->traceEvent(category, name, type, id, args, extra);
    }
}
 
inline void traceEvent(const QLoggingCategory& category, const QString& name, EventType type, int id, const QVariantMap& args = {}, const QVariantMap& extra = {}) {
    traceEvent(category, name, type, QString::number(id), args, extra);
}
 
}
 
#endif // hifi_Trace_h