hangdetector_utils.h

/*
 * If not stated otherwise in this file or this component's Licenses.txt file the
 * following copyright and licenses apply:
 *
 * Copyright 2016 RDK Management
 *
 * 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 HANGDETECTOR_UTILS_H
#define HANGDETECTOR_UTILS_H
 
#include <glib.h>
#include "logger.h"
 
#include <thread>
#include <atomic>
#include <sys/types.h>
#include <unistd.h>
 
namespace Utils
{
 
class HangDetector
{
    std::unique_ptr<std::thread> m_thread;
    std::atomic_bool m_running {false};
    std::atomic_int  m_resetCount {0};
    std::atomic_int m_threshold {30};
 
    void runWatchDog()
    {
        while(m_running)
        {
            std::this_thread::sleep_for(std::chrono::seconds(1));
            if (m_resetCount > m_threshold)
            {
                printf("hang detected\n"); fflush(stdout);
                kill(getpid(), SIGFPE);
            }
            else if (m_resetCount > (m_threshold / 2))
            {
                printf("hang detector will force crash in %d seconds...\n", m_threshold - m_resetCount); fflush(stdout);
            }
            ++m_resetCount;
        }
    }
 
    void resetWatchDog()
    {
        m_resetCount = 0;
    }
 
    void initThreshold()
    {
        const char* var = getenv("RTRMFPLAYER_HANG_DETECTOR_THRESHOLD_SEC");
        if (var)
        {
            try
            {
                int tmp = std::atoi(var);
                if (tmp > 5)
                {
                    m_threshold = tmp;
                }
            } catch (...) {}
        }
    }
 
public:
    ~HangDetector()
    {
        stop();
    }
 
    void start()
    {
        if (m_thread)
            return;
        initThreshold();
 
        m_running = true;
 
        g_timeout_add_seconds(1, [](gpointer data) -> gboolean {
            static_cast<HangDetector*>(data)->resetWatchDog();
            return G_SOURCE_CONTINUE;
        }, this);
 
        m_thread.reset(new std::thread(&HangDetector::runWatchDog, this));
    }
 
    void stop()
    {
        m_running = true;
        m_thread->join();
    }
};
 
} // namespace utils
 
#endif // HANGDETECTOR_H