gui/dboxinfo: move cpu load calculation to dedicated thread ...

... that keeps history; show load graph


Origin commit data
------------------
Branch: ni/coolstream
Commit: ce18925333
Author: vanhofen <vanhofen@gmx.de>
Date: 2013-12-30 (Mon, 30 Dec 2013)



------------------
This commit was generated by Migit

src/system/sysload.cpp

@@ -0,0 +1,115 @@
+/*
+	Neutrino-HD
+
+	License: GPL
+
+	(C) 2013 martii
+
+	This program is free software; you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation; either version 2 of the License, or
+	(at your option) any later version.
+
+	This program is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with this program; if not, write to the Free Software
+	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef __USE_FILE_OFFSET64
+#define __USE_FILE_OFFSET64 1
+#endif
+
+#include <string>
+#include <iostream>
+#include <fstream>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/vfs.h>
+#include <fcntl.h>
+#include <time.h>
+#include <stdarg.h>
+#include <global.h>
+#include <system/set_threadname.h>
+#include <system/sysload.h>
+
+static cSysLoad *instance = NULL;
+
+cSysLoad *cSysLoad::getInstance(void)
+{
+	if (!instance)
+		instance = new cSysLoad;
+	return instance;
+}
+
+void *cSysLoad::Run(void *arg)
+{
+	set_threadname("sysload");
+
+	class cSysLoad *caller = (class cSysLoad *)arg;
+	unsigned long stat_idle = 0, stat_total = 0;
+
+	while (caller->running) {
+		std::ifstream in("/proc/stat");
+		if (in.is_open()) {
+			std::string line;
+			while (getline(in, line)) {
+				unsigned long _stat_user, _stat_nice, _stat_system, _stat_idle;
+				if (4 == sscanf(line.c_str(), "cpu %lu %lu %lu %lu", &_stat_user, &_stat_nice, &_stat_system, &_stat_idle)) {
+					if (stat_total) {
+						unsigned long div = _stat_user + _stat_nice + _stat_system + _stat_idle - stat_total;
+						caller->data_last = (int)(1000 - 1000 * (_stat_idle - stat_idle) / div);
+						if (caller->data_avail < caller->data_size) {
+							caller->data[caller->data_avail++] = caller->data_last;
+						} else {
+							memmove(caller->data, caller->data + 1, (caller->data_size - 1) * sizeof(int));
+							caller->data[caller->data_size - 1] = caller->data_last;
+						}
+					}
+					stat_idle = _stat_idle;
+					stat_total = _stat_user + _stat_nice + _stat_system + _stat_idle;
+					break;
+				}
+			}
+			in.close();
+		}
+
+		timespec ts;
+		clock_gettime(CLOCK_REALTIME, &ts);
+		ts.tv_sec += caller->period;
+		sem_timedwait(&caller->sem, &ts);
+	}
+	pthread_exit(NULL);
+}
+
+cSysLoad::cSysLoad(void)
+{
+	data_last = -1;
+	data_avail = 0;
+	period = 5;
+	data_size = 1800/period;
+	data = new int[data_size];
+	for (unsigned int i = 0; i < data_size; i++)
+		data[i] = -1;
+	running = true;
+	sem_init(&sem, 0, 0);
+	if (pthread_create(&thr, NULL, Run, this))
+		running = false;
+}
+
+cSysLoad::~cSysLoad(void)
+{
+	if (running) {
+		running = false;
+		sem_post(&sem);
+		pthread_join(thr, NULL);
+	}
+	sem_destroy(&sem);
+	delete[] data;
+}