add front demo in this project

LFtid1056/cloudfront/code/log4cplus/helpers/eventcounter.h

@@ -0,0 +1,91 @@
+// -*- C++ -*-
+//
+//  Copyright (C) 2024, Vaclav Haisman. All rights reserved.
+//
+//  Redistribution and use in source and binary forms, with or without modifica-
+//  tion, are permitted provided that the following conditions are met:
+//
+//  1. Redistributions of  source code must  retain the above copyright  notice,
+//     this list of conditions and the following disclaimer.
+//
+//  2. Redistributions in binary form must reproduce the above copyright notice,
+//     this list of conditions and the following disclaimer in the documentation
+//     and/or other materials provided with the distribution.
+//
+//  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
+//  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+//  FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
+//  APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
+//  INDIRECT, INCIDENTAL, SPECIAL,  EXEMPLARY, OR CONSEQUENTIAL  DAMAGES (INCLU-
+//  DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
+//  OF USE, DATA, OR  PROFITS; OR BUSINESS  INTERRUPTION)  HOWEVER CAUSED AND ON
+//  ANY  THEORY OF LIABILITY,  WHETHER  IN CONTRACT,  STRICT LIABILITY,  OR TORT
+//  (INCLUDING  NEGLIGENCE OR  OTHERWISE) ARISING IN  ANY WAY OUT OF THE  USE OF
+//  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef LOG4CPLUS_HELPERS_EVENTCOUNTER_H
+#define LOG4CPLUS_HELPERS_EVENTCOUNTER_H
+
+#include <log4cplus/config.hxx>
+
+#if defined (LOG4CPLUS_HAVE_PRAGMA_ONCE)
+#pragma once
+#endif
+
+#include <log4cplus/thread/syncprims.h>
+#include <cstddef>
+#include <atomic>
+#include <chrono>
+
+
+namespace log4cplus {
+
+namespace helpers {
+
+class LOG4CPLUS_EXPORT BaseEventCounter
+{
+public:
+    BaseEventCounter ();
+    virtual ~BaseEventCounter ();
+
+    virtual std::size_t record_event ();
+
+protected:
+    std::atomic<std::size_t> event_count {0};
+};
+
+
+class LOG4CPLUS_EXPORT SteadyClockGate
+    : public BaseEventCounter
+{
+public:
+    using Clock = std::chrono::steady_clock;
+    using Duration = Clock::duration;
+    using TimePoint = std::chrono::time_point<Clock>;
+
+    struct LOG4CPLUS_EXPORT Info
+    {
+        ~Info ();
+
+        std::size_t count;
+        Duration time_span;
+    };
+
+    SteadyClockGate (SteadyClockGate::Duration pause_duraiton);
+    virtual ~SteadyClockGate ();
+
+    bool latch_open (Info &);
+
+private:
+    log4cplus::thread::SimpleMutex mtx;
+    Duration const pause_duration;
+    TimePoint timeout_point;
+    TimePoint prev_timeout_point;
+};
+
+
+} // namespace helpers
+
+} // namespace log4cplus
+
+#endif // LOG4CPLUS_HELPERS_EVENTCOUNTER_H