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 70 行

/* $Id: uptime.c,v 1.18 2003/10/19 16:55:39 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 <config.h>
#include <glibtop/error.h>
#include <glibtop/uptime.h>

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

/* Init function. */

void
glibtop_init_uptime_s (glibtop *server)
{
	server->sysdeps.uptime = _glibtop_sysdeps_uptime;
}

/* Provides uptime and idle time. */

#define FILENAME	"/proc/uptime"

void
glibtop_get_uptime_s (glibtop *server, glibtop_uptime *buf)
{
	char buffer [BUFSIZ], *p;
	int fd, len;

	glibtop_init_s (&server, GLIBTOP_SYSDEPS_UPTIME, 0);

	memset (buf, 0, sizeof (glibtop_uptime));

	fd = open (FILENAME, O_RDONLY);
	if (fd < 0)
		glibtop_error_io_r (server, "open (%s)", FILENAME);

	len = read (fd, buffer, BUFSIZ-1);
	if (len < 0)
		glibtop_error_io_r (server, "read (%s)", FILENAME);

	close (fd);

	buffer [len] = '\0';

	buf->uptime   = strtod (buffer, &p);
	buf->idletime = strtod (p, &p);

	buf->flags = _glibtop_sysdeps_uptime;
}