/* flashy.c */
/* program for displaying the current processor usage as a bar of leds on the
 * parallel port.  Uses the parapin driver/library  http://parapin.sf.net */
/* 1/26/05 eric buehl; eric@thebuehls.com */

#define SAMPLE 500000  /* the delay time between sampling processor usage */

#include <stdio.h>
#include <parapin.h>

int main(int argc, char ** argv)
{
	FILE * proc;
	char buffer[25];
	long user_i=0,user=0;
	long nice_i=0,nice=0;
	long system_i=0,system=0;
	long idle_i=0,idle=0;
	float usage=0.0;
	int x=0;

	pin_init_user(LPT1);
	pin_mode(LP_PIN02, LP_OUTPUT);
	
	while(1)
	{
		clear_pin((1<<8)-1);
		x=((1<<((int)(7*usage+1)))-1);
		set_pin(x);
		if(argc-1)
			printf("%f  %i\n",usage,x);
		proc=fopen("/proc/stat","r");
		if(proc==NULL) return -1;
		/* seek to the part about the cpu; the part we want! */
		while(strcmp(buffer,"cpu")&&buffer[0]!=EOF)
			fscanf(proc,"%s",&buffer);
		fscanf(proc,"%s",buffer);
		user_i=atoi(buffer);
		fscanf(proc,"%s",buffer);
		nice_i=atoi(buffer);
		fscanf(proc,"%s",buffer);
		system_i=atoi(buffer);
		fscanf(proc,"%s",buffer);
		idle_i=atoi(buffer);
		
		/* compute the current processor usage in percent as a decimal */
		usage=1-((float)(idle_i-idle)/((user_i-user)+(nice_i-nice)+(system_i-system)+(idle_i-idle)));
		
		user=user_i;
		nice=nice_i;
		system=system_i;
		idle=idle_i;
	
		fclose(proc);
		usleep(SAMPLE);
	}

}