conky/metarinfo.c

#include "conky.h"
#include <string.h>
#include "ftp.h"
#include <math.h>
#include <pthread.h>
#include "metarinfo.h"

/* for threads */
static int status = 0;


int calculateRelativeHumidity(int temp, int dew) {
	float rh = 0.0;
	rh = 100.0 * powf ((112 - (0.1 * temp)+dew ) / (112 + (0.9 * temp)), 8);
	return (int)rh;
}

int calculateWindChill(int temperatureC, int windKn) {
	double windKmh = knTokph(windKn);
	return (int)(13.112+0.6215*temperatureC - 11.37*powf(windKmh,.16) + 0.3965*temperatureC*powf(windKmh,.16) );
}

int knTokph(int knSpeed ){
	return (knSpeed * 1.852);
}

const char *calculateWindDirectionString(int degree) {
	if (degree < 22.5) {
		return "North";
	} else if (degree < 67.5){
		return "Northeast";
	} else if (degree < 112.5) {
		return "East";
	} else if (degree < 157.5) {
		return "Southeast";
	} else if (degree < 202.5){
		return "South";
	} else if (degree < 247.5) {
		return "Southwest";
	} else if (degree < 292.5) {
		return "West";
	} else if (degree < 337.5){
		return "Northwest";
	} else {
		return "North";
	}
}
const char*calculateShortWindDirectionString(int degree){
	if (degree < 22.5) {
		return "N";
	} else if (degree < 67.5){
		return "NE";
	} else if (degree < 112.5) {
		return "E";
	} else if (degree < 157.5) {
		return "SE";
	} else if (degree < 202.5){
		return "S";
	} else if (degree < 247.5) {
		return "SW";
	} else if (degree < 292.5) {
		return "W";
	} else if (degree < 337.5){
		return "NW";
	} else {
		return "N";
	}
}

void ftpData(void *userData, const char *data, int len)
{

	if (len <= 0)
		return;

	if ( data != NULL ){
		line = strdup(data);
	}
}


void *fetch_ftp( ) {
		// try three times if it fails
	int tries = 0;
	do {
		if (tries > 0) {
			/* this happens too often, so i'll leave it commented fprintf(stderr, "METAR update failed for some reason, retry %i\n", tries); */
			sleep(15); /* give it some time in case the server is busy or down */
		}
		tries++;
		if ( strlen(metar_station) != 8 ){
			fprintf(stderr,"You didn't supply a valid station code\n");     
			return;
		}
		if (metar_server == NULL)
			metar_server = strdup("weather.noaa.gov");
		if (metar_path == NULL)
			metar_path = strdup("/data/observations/metar/stations");
		
		int res;
		initFtp();
		res = connectFtp(metar_server, 0);
		if (res < 0) {
			fprintf(stderr, "Couldn't connect to %s\n", metar_server);
			return;
		}
		res = changeFtpDirectory(metar_path);
		if (res < 0) {
			fprintf(stderr, "Metar update failed (couldn't CWD to %s)\n", metar_path);
			disconnectFtp();
			return;
		}
		if (res == 0) {
			fprintf(stderr,
				"Metar update failed\n");
			return;
		}
		if (getFtp(ftpData, NULL, metar_station) < 0) {
			fprintf(stderr, "Failed to get file %s\n", metar_station);
		}
		
		disconnectFtp();
		if ( line != NULL ){
			dcdNetMETAR(line, &data);
			free(line);
			line = NULL;
			ftp_ok = 1;
			metar_worked = 1;
		}
		else {
			ftp_ok = 0;
		}

	} while (ftp_ok == 0 && tries < 3);
	status = 1;
}

static pthread_t thread1;

void update_metar() {
	int  iret1;
	if (!status) {
		status = 2;
		iret1 = pthread_create( &thread1, NULL, fetch_ftp, NULL);
	}
	else if (status == 2) { /* thread is still running.  what else can we do? */
		return;
	}
	else {
		pthread_join( thread1, NULL);
		status = 2;
		iret1 = pthread_create( &thread1, NULL, fetch_ftp, NULL);
	}
	
}