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/* $Id$
* $URL$
*
* plugin for load average
*
* Copyright (C) 2003 Michael Reinelt <michael@reinelt.co.at>
* Copyright (C) 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
*
* This file is part of LCD4Linux.
*
* LCD4Linux 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, or (at your option)
* any later version.
*
* LCD4Linux 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.
*
*/
/*
* exported functions:
*
* int plugin_init_loadavg (void)
* adds functions for load average
*
*/
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <fcntl.h>
#include "debug.h"
#include "plugin.h"
#ifndef HAVE_GETLOADAVG
static int fd = -2;
int getloadavg(double loadavg[], int nelem)
{
char buf[65], *p;
ssize_t nread;
int i;
if (fd == -2)
fd = open("/proc/loadavg", O_RDONLY);
if (fd < 0)
return -1;
lseek(fd, 0, SEEK_SET);
nread = read(fd, buf, sizeof buf - 1);
if (nread < 0)
return -1;
buf[nread - 1] = '\0';
if (nelem > 3)
nelem = 3;
p = buf;
for (i = 0; i < nelem; ++i) {
char *endp;
loadavg[i] = strtod(p, &endp);
if (endp == NULL || endp == p)
/* This should not happen. The format of /proc/loadavg
must have changed. Don't return with what we have,
signal an error. */
return -1;
p = endp;
}
return i;
}
#endif
static void my_loadavg(RESULT * result, RESULT * arg1)
{
static int nelem = -1;
int index, age;
static double loadavg[3];
static struct timeval last_value;
struct timeval now;
gettimeofday(&now, NULL);
age = (now.tv_sec - last_value.tv_sec) * 1000 + (now.tv_usec - last_value.tv_usec) / 1000;
/* reread every 10 msec only */
if (nelem == -1 || age == 0 || age > 10) {
nelem = getloadavg(loadavg, 3);
if (nelem < 0) {
error("getloadavg() failed!");
SetResult(&result, R_STRING, "");
return;
}
last_value = now;
}
index = R2N(arg1);
if (index < 1 || index > nelem) {
error("loadavg(%d): index out of range!", index);
SetResult(&result, R_STRING, "");
return;
}
SetResult(&result, R_NUMBER, &(loadavg[index - 1]));
return;
}
int plugin_init_loadavg(void)
{
AddFunction("loadavg", 1, my_loadavg);
return 0;
}
void plugin_exit_loadavg(void)
{
#ifndef HAVE_GETLOADAVG
if (fd > 0)
close(fd);
fd = -2;
#endif
}
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