system.c

#include <sys/types.h>
#include <sys/sysctl.h>

#include <err.h>
#include <stdbool.h>
#include <sysexits.h>
#include <unistd.h>

#include "common.h"
#include "system.h"

#define INVALID_MODE_ERROR "Invalid fan mode"
#define PERMISSION_ERROR "Not enough permissions"
#define KELVIN_TO_CELSIUS(t) ((t-2732+5)/10)

static int idx_cur_level;
static int mib_set_fan_level[4];
static int mib_get_temp_level[4];
static int mib_get_temp_level_alt[5];
static bool temp_alt = false;

static void levelDown(const struct Level *levels);
static void levelUp(const struct Level *levels);

/*sets fan in either manual or auto mode, in manual sets the lowest defined level and calculates mib_get_fan_level and mib_get_temp_level*/ 
void
setFan(int mode, const struct Level *levels)
{
	switch (mode) {
	case MANUAL:
	case AUTO:
		/*set fan in manual mode*/
		if (sysctlbyname("dev.acpi_ibm.0.fan",NULL,NULL,&mode,sizeof(int)) == -1)
			err(EX_NOPERM, PERMISSION_ERROR);

		if (mode == AUTO)
			break;

		/*get mib for dev.acpi_ibm.0.fan_level*/
		size_t len=4; 
		sysctlnametomib("dev.acpi_ibm.0.fan_level",mib_set_fan_level,&len);

		/*get mib for dev.acpi_ibm.0.thermal*/
		len = 4;
		if (sysctlnametomib("dev.acpi_ibm.0.thermal",mib_get_temp_level,&len) == -1)
		{
			len = 5;
			/*get mib for hw.acpi.thermal.tz0.temperature*/
			sysctlnametomib("hw.acpi.thermal.tz0.temperature",mib_get_temp_level_alt,&len);
			temp_alt=true;
		}

		/*set lowest available level*/
		len = 4;

		sysctl(mib_set_fan_level,4,NULL,NULL,&levels[0].number,sizeof(int));
		idx_cur_level = 0;
		break;
	default:
		errx(EX_SOFTWARE, INVALID_MODE_ERROR);
	}
}

void
adjustLevel(int t, const struct Config *conf) /*t for temp*/
{
		if( t < conf->levels[idx_cur_level].min_max[0] )
			levelDown(conf->levels);

		else if( t > conf->levels[idx_cur_level].min_max[1])
			levelUp(conf->levels);
}

static void
levelUp(const struct Level *levels)
{
	sysctl(mib_set_fan_level,4,NULL,NULL,&levels[idx_cur_level+1].number,sizeof(int));
	idx_cur_level++;
}

static void
levelDown(const struct Level *levels)
{
	sysctl(mib_set_fan_level,4,NULL,NULL,&levels[idx_cur_level-1].number,sizeof(int));
	idx_cur_level--;
}

int
getTemp()
{
	int temp[8]={0};
	size_t len = 8*sizeof(int);
	if(temp_alt)
	{
		sysctl(mib_get_temp_level_alt,5,&temp,&len,NULL,0);
		return KELVIN_TO_CELSIUS(temp[0]);
	}
	else
		sysctl(mib_get_temp_level,4,&temp,&len,NULL,0);

	return temp[0];

}