Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include "dat.h"

Place nowhere = {
        Undef, Undef
};

static void
setlat(Place *p, double lat)
{
        p->lat = lat;
}

static void
setlon(Place *p, double lon)
{
        p->lon = lon;
}

static int
printlatlon(char *p, int n, double lat, char po, char ne)
{
        char c;
        double d;
        int deg, min, sec;

        if(lat > 0)
                c = po;
        else if(lat < 0){
                c = ne;
                lat = -lat;
        } else
                c = ' ';
        sec = 3600 * modf(lat, &d);
        deg = d;
        min = sec/60;
        sec = sec % 60;
        return snprint(p, n, "%#3.3d°%#2.2d′%#2.2d″%c", deg, min, sec, c);
}

int
placeconv(Fmt *fp)
{
        char str[256];
        int n;
        Place pl;

        pl = va_arg(fp->args, Place);
        n = 0;
        n += printlatlon(str+n, sizeof(str)-n, pl.lat, 'N', 'S');
        n += snprint(str+n, sizeof(str)-n, ", ");
        printlatlon(str+n, sizeof(str)-n, pl.lon, 'E', 'W');
        return fmtstrcpy(fp, str);
}

int
strtolatlon(char *p, char **ep, Place *pl)
{
        double latlon;
        int neg = 0;

        while(*p == '0') p++;
        latlon = strtod(p, &p);
        if(latlon < 0){
                latlon = -latlon;
                neg = 1;
        }
        if(*p == ':'){
                p++;
                while(*p == '0') p++;
                latlon += strtod(p, &p)/60.0;
                if(*p == ':'){
                        p++;
                        while(*p == '0') p++;
                        latlon += strtod(p, &p)/3600.0;
                }
        }
        switch (*p++){
        case 'N':
        case 'n':
                if(neg) latlon = -latlon;
                if(pl->lat != Undef)
                        return -1;
                setlat(pl, latlon);
                break;
        case 'S':
        case 's':
                if(!neg) latlon = -latlon;
                if(pl->lat != Undef)
                        return -1;
                setlat(pl, latlon);
                break;
        case 'E':
        case 'e':
                if(neg) latlon = -latlon;
                if(pl->lon != Undef)
                        return -1;
                setlon(pl, latlon);
                break;
        case 'W':
        case 'w':
                if(!neg) latlon = -latlon;
                if(pl->lon != Undef)
                        return -1;
                setlon(pl, latlon);
                break;
        case '\0':
        case ' ':
        case '\t':
        case '\n':
                p--;
                if(neg) latlon = -latlon;
                if(pl->lat == Undef){
                        setlat(pl, latlon);
                } else if(pl->lon == Undef){
                        latlon = -latlon;
                        setlon(pl, latlon);
                } else return -1;
                break;
        default:
                return -1;
        }
        if(ep)
                *ep = p;
        return 0;
}

Place
strtopos(char *p, char **ep)
{
        Place pl = nowhere;

        if(strtolatlon(p, &p, &pl) < 0)
                return nowhere;
        while(*p == ' ' || *p == '\t' || *p == '\n')
                p++;
        if(strtolatlon(p, &p, &pl) < 0)
                return nowhere;
        if(ep)
                *ep = p;
        return pl;
}

static void
rtcset(long t)          /* We may use this some day */
{
        static int fd;
        long r;
        int n;
        char buf[32];

        if(fd <= 0 && (fd = open("#r/rtc", ORDWR)) < 0){
                fprint(2, "Can't open #r/rtc: %r\n");
                return;
        }
        n = read(fd, buf, sizeof buf - 1);
        if(n <= 0){
                fprint(2, "Can't read #r/rtc: %r\n");
                return;
        }
        buf[n] = '\0';
        r = strtol(buf, nil, 0);
        if(r <= 0){
                fprint(2, "ridiculous #r/rtc: %ld\n", r);
                return;
        }
        if(r - t > 1 || t - r > 0){
                seek(fd, 0, 0);
                fprint(fd, "%ld", t);
                fprint(2, "correcting #r/rtc: %ld → %ld\n", r, t);
        }
        seek(fd, 0, 0);
}