uptime.c

来自「linux 操作系统下对系统资源监控程序的编写」· C语言 代码 · 共 62 行

/* $Id: uptime.c,v 1.14 2003/10/19 16:55:56 carlos Exp $ */

/* Copyright (C) 1998-99 Martin Baulig
   This file is part of LibGTop 1.0.

   Contributed by Martin Baulig <[e-mail]>, April 1998.

   LibGTop 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.

   LibGTop 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 LibGTop; see the file COPYING. If not, write to the
   Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.
*/

#include <glibtop.h>
#include <glibtop/cpu.h>
#include <glibtop/uptime.h>

#include <glibtop_suid.h>

static const unsigned long _glibtop_sysdeps_uptime =
(1 << GLIBTOP_UPTIME_UPTIME) + (1 << GLIBTOP_UPTIME_IDLETIME);

/* Provides uptime and idle time. */

void
glibtop_get_uptime_p (glibtop *server, glibtop_uptime *buf)
{
	glibtop_cpu cpu;

	glibtop_init_p (server, (1 << GLIBTOP_SYSDEPS_UPTIME), 0);

	/* Get currect cpu usage. */

	glibtop_get_cpu_p (server, &cpu);

	/* Make sure all required fields are present. */

	if (((cpu.flags & (1 << GLIBTOP_CPU_TOTAL)) == 0) ||
	    ((cpu.flags & (1 << GLIBTOP_CPU_IDLE)) == 0) ||
	    ((cpu.flags & (1 << GLIBTOP_CPU_FREQUENCY)) == 0) ||
	    (cpu.frequency == 0))
		return;

	/* Simply calculate uptime and idle time from
	 * cpu usage. */

	buf->uptime = (double) cpu.total / (double) cpu.frequency;
	buf->idletime = (double) cpu.idle / (double) cpu.frequency;

	buf->flags = _glibtop_sysdeps_uptime;
}