dockapps/wmweather+/metar.c
2014-10-05 19:18:49 +01:00

437 lines
12 KiB
C

#include "config.h"
/* Copyright (C) 2002 Brad Jorsch <anomie@users.sourceforge.net>
This program 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 of the License, or
(at your option) any later version.
This program 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <unistd.h>
#if TM_IN_SYS_TIME
# if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
# else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# include <time.h>
# endif
# endif
#else
#include <time.h>
#endif
#include <string.h>
#include <ctype.h>
#include <math.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <pcre.h>
#include "wmweather+.h"
#include "metar.h"
#include "warnings.h"
#include "download.h"
#include "convert.h"
#include "die.h"
#include "sunzenith.h"
#include "moon.h"
#include "subst.h"
/* Important variables */
static time_t metar_time=0;
static char *metar_newfile=NULL;
static char *metar_file=NULL;
static char *metar_req[2]={ NULL, NULL };
struct current_weather current;
/* Regular Expressions */
static pcre *station_time;
static pcre *wind;
static pcre *weather;
static pcre *vis[4];
static pcre *temp;
static pcre *pressure;
static int ovecsize;
/* prototypes */
static int parse_metar(char *file);
/* functions */
static void reset_current(struct current_weather *c){
c->last_update=time(NULL);
c->month=0;
c->date=-1;
c->time=-1;
c->temp=999;
c->rh=-1;
c->winddir=-1;
c->windspeed=-1;
c->pressure=-1;
c->heatindex=999;
c->windchill=999;
c->sky=-1;
c->vis=7;
c->obs=0;
c->frz=0;
c->snow=0;
c->rain=0;
c->tstorm=0;
c->moon=NAN;
}
#define compile(var, re) \
var=pcre_compile(re, 0, (const char **)&e, &i, NULL); \
if(var==NULL) die("init_metar PCRE error: %s at %i", e, i); \
pcre_fullinfo(var, NULL, PCRE_INFO_CAPTURECOUNT, &i); \
if(i>ovecsize) ovecsize=i;
void init_metar(void){
int i;
char *e;
struct subst_val subs[]={
{ 's', STRING, &metar_station },
{ 0, 0, 0 }
};
snprintf(bigbuf, BIGBUF_LEN, "%s.metar.txt", metar_station);
metar_file=get_pid_filename(bigbuf);
snprintf(bigbuf, BIGBUF_LEN, "%s.new-metar.txt", metar_station);
metar_newfile=get_pid_filename(bigbuf);
if((metar_req[0]=subst(metar_uri, subs))==NULL) die("init_metar");
if(metar_post!=NULL && (metar_req[1]=subst(metar_post, subs))==NULL) die("init_metar");
metar_time=0;
ovecsize=0;
strncpy(bigbuf, metar_station, BIGBUF_LEN-25);
bigbuf[BIGBUF_LEN-25]='\0';
strcat(bigbuf, " ((?:\\d\\d)?)(\\d\\d\\d\\d)Z( .* )");
compile(station_time, bigbuf);
compile(wind, " (VRB|\\d\\d\\d)(\\d\\d\\d?)(?:G\\d\\d\\d?)?(KT|MPS|KMH)((?: \\d\\d\\dV\\d\\d\\d)?) ");
compile(weather, " ((?:-|\\+|VC)?)((?:MI|PR|BC|DR|BL|SH|TS|FZ)?)((?:DZ|RA|SN|SG|IC|PE|PL|GR|GS|UP){0,3})((?:BR|FG|FU|VA|DU|SA|HZ|PY)?)((?:PO|SQ|FC|SS|DS)?)\\b");
compile(vis[0], " (\\d+)SM ");
compile(vis[1], " (\\d+)/(\\d+)SM ");
compile(vis[2], " (\\d+) (\\d+)/(\\d+)SM ");
compile(vis[3], " (\\d{4})[NS]?[EW]? ");
compile(temp, " (M?\\d\\d\\d?)/((?:M?\\d\\d\\d?)?) ");
compile(pressure, " ([AQ])(\\d\\d\\d\\d) ");
ovecsize=(ovecsize+1)*3;
/* Remove stale file */
unlink(metar_file);
unlink(metar_newfile);
reset_current(&current);
current.last_update = 0; // This was not a real "update", just an init
}
#undef compile
static void metar_callback(char *filename, void *v){
struct stat statbuf;
if(stat(metar_newfile, &statbuf)>=0){
if(S_ISREG(statbuf.st_mode) && statbuf.st_size!=0
&& parse_metar(metar_newfile)){
rename(metar_newfile, metar_file);
} else {
unlink(metar_newfile);
if(!parse_metar(metar_file)) reset_current(&current);
}
}
update_warnings(v!=NULL);
}
void metar_cleanup(void){
unlink(metar_newfile);
unlink(metar_file);
}
void update_metar(int force){
time_t t;
t=time(NULL)/60;
if(!force && metar_time>t) return;
metar_time=t+15;
download_file(metar_newfile, metar_req[0], metar_req[1], force?DOWNLOAD_KILL_OTHER_REQUESTS:0, metar_callback, force?"":NULL);
}
#define get_substr(n, c) \
if(pcre_get_substring(s, ovector, ovalue, n, (const char **)&c)<0){ pcre_free_substring(s); return 0; }
static int parse_metar(char *file){
FILE *fp;
char *s, *c;
int ovector[ovecsize];
int ovalue;
int len;
float f;
int i, j;
reset_current(&current);
if((fp=fopen(file, "r"))==NULL) return 0;
len=fread(bigbuf, sizeof(char), BIGBUF_LEN-2, fp);
fclose(fp);
if(len<1) return 0;
for(i=0; i<len; i++){
if(isspace(bigbuf[i])) bigbuf[i]=' ';
}
c=strstr(bigbuf, " RMK");
if(c!=NULL) *(c+1)='\0';
c=strstr(bigbuf, " TEMPO");
s=strstr(bigbuf, " BECMG");
if(c!=NULL) *(c+1)='\0';
if(s!=NULL) *(s+1)='\0';
/* XXX: parse trend forecast data? */
len=strlen(bigbuf);
if(bigbuf[len-1]!=' '){
bigbuf[len++]=' ';
bigbuf[len]='\0';
}
/* Look for something like a METAR coded report */
ovalue=pcre_exec(station_time, NULL, bigbuf, len, 0, 0, ovector, ovecsize);
if(ovalue<=0) return 0;
if(pcre_get_substring(bigbuf, ovector, ovalue, 1, (const char **)&c)<0) return 0;
if(c[0]!='\0') current.date=atoi(c);
pcre_free_substring(c);
if(pcre_get_substring(bigbuf, ovector, ovalue, 2, (const char **)&c)<0) return 0;
current.time=atoi(c);
pcre_free_substring(c);
/* Chop off extraneous stuff */
if(pcre_get_substring(bigbuf, ovector, ovalue, 3, (const char **)&s)<0) return 0;
/* windspeed, winddir */
ovalue=pcre_exec(wind, NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(4, c);
if(c[0]!='\0'){
current.winddir=0;
} else {
pcre_free_substring(c);
get_substr(1, c);
if(c[0]=='V') current.winddir=0;
else current.winddir=((int)((atoi(c)+11.25)/22.5))%16+1;
}
pcre_free_substring(c);
get_substr(2, c);
current.windspeed=atoi(c);
pcre_free_substring(c);
get_substr(3, c);
if(c[0]=='M'){ /* MPS */
current.windspeed=mps2knots(current.windspeed);
} else if(c[0]=='K' && c[1]=='M'){ /* KMH */
current.windspeed=kph2knots(current.windspeed);
}
}
/* vis */
f=99;
c=strstr(s, " M1/4SM ");
if(c!=NULL){
f=0;
goto wind_done;
}
ovalue=pcre_exec(vis[2], NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(2, c);
i=atoi(c);
pcre_free_substring(c);
get_substr(3, c);
j=atoi(c);
pcre_free_substring(c);
get_substr(1, c);
f=atoi(c)+(float)i/j;
pcre_free_substring(c);
goto wind_done;
}
ovalue=pcre_exec(vis[1], NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(2, c);
i=atoi(c);
pcre_free_substring(c);
get_substr(1, c);
f=(float)atoi(c)/i;
pcre_free_substring(c);
goto wind_done;
}
ovalue=pcre_exec(vis[0], NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(1, c);
f=atoi(c);
pcre_free_substring(c);
goto wind_done;
}
c=strstr(s, " CAVOK ");
if(c!=NULL){
f=99;
current.sky=0;
goto wind_done;
}
ovalue=pcre_exec(vis[3], NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(1, c);
f=m2mi(atoi(c));
pcre_free_substring(c);
goto wind_done;
}
wind_done:
if(f<=6) current.vis=6;
if(f<=5) current.vis=5;
if(f<3) current.vis=4;
if(f<1) current.vis=3;
if(f<=.5) current.vis=2;
if(f<=.25) current.vis=1;
/* temp, rh */
ovalue=pcre_exec(temp, NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(1, c);
if(c[0]=='M') c[0]='-';
current.temp=atoi(c);
pcre_free_substring(c);
get_substr(2, c);
if(c[0]!='\0'){
if(c[0]=='M') c[0]='-';
current.rh=rh_C(current.temp, atoi(c));
}
pcre_free_substring(c);
}
/* pressure */
ovalue=pcre_exec(pressure, NULL, s, len, 0, 0, ovector, ovecsize);
if(ovalue>0){
get_substr(2, c);
i=atoi(c);
pcre_free_substring(c);
get_substr(1, c);
if(c[0]=='Q'){
current.pressure=hPa2inHg(i);
} else {
current.pressure=i/100.0;
}
pcre_free_substring(c);
}
/* sky */
if(strstr(s, " SKC")!=NULL || strstr(s, " CLR")!=NULL) current.sky=0;
if(strstr(s, " FEW")!=NULL) current.sky=1;
if(strstr(s, " SCT")!=NULL) current.sky=2;
if(strstr(s, " BKN")!=NULL) current.sky=3;
if(strstr(s, " OVC")!=NULL || strstr(s, " VV")!=NULL) current.sky=4;
/* obs, frz, snow, rain, tstorm */
/* There can be multiple weather chunks, so we while loop */
j=0;
while((ovalue=pcre_exec(weather, NULL, s, len, j, 0, ovector, ovecsize))>0){{
char *in, *de, *pp, *ob, *ot;
j=ovector[0]+1;
get_substr(0, c);
i=(c[1]=='\0');
pcre_free_substring(c);
if(i) continue;
get_substr(1, in);
get_substr(2, de);
get_substr(3, pp);
get_substr(4, ob);
get_substr(5, ot);
#define IN(haystack, needle) ((needle[0]=='\0')?0:strstr(haystack, needle))
if(current.obs<1 && strcmp(de, "FZ") && IN("BR|FG", ob))
current.obs=1;
if(current.obs<2 && IN("FU|VA|DU|SA|HZ|PY", ob))
current.obs=2;
if(current.obs<3 && IN("PO|SS|DS", ot))
current.obs=3;
if(current.obs<3 && IN("DR|BL", de)
&& (strstr(pp, "SN") || IN("DU|SA|PY", ob)))
current.obs=3;
if(!strcmp(ot, "FC")){
current.sky=5;
current.obs=99;
current.vis=7;
}
#undef IN
i=66;
if(in[0]=='-' || in[0]=='V') i=33;
if(in[0]=='+') i=99;
if(!strcmp(de, "SH")) i=33;
if(current.frz<i
&& ((!strcmp(de, "FZ") && (strstr(pp, "DZ") || strstr(pp, "RA")))
|| strstr(pp, "IC") || strstr(pp, "PE") || strstr(pp, "PL")
|| strstr(pp, "GR") || strstr(pp, "GS")))
current.frz=i;
if(current.snow<i && strcmp(de, "BL")
&& (strstr(pp, "SN") || strstr(pp, "SG")))
current.snow=i;
if(current.rain<i && (strstr(pp, "UP")
|| (strcmp(de, "FZ")
&& (strstr(pp, "DZ") || strstr(pp, "RA")))))
current.rain=i;
if(current.tstorm<i && !strcmp(de, "TS"))
current.tstorm=i;
pcre_free_substring(in);
pcre_free_substring(de);
pcre_free_substring(pp);
pcre_free_substring(ob);
pcre_free_substring(ot);
}}
if(current.obs==99) current.obs=0;
pcre_free_substring(s); /* Done parsing! Just a few final calculations... */
current.heatindex=heatindex_C(current.temp, current.rh);
current.windchill=windchill_C(current.temp, current.windspeed);
/* Figure out the proper month... */
{
int mon, day, year, time2; /* holds UTC */
int y; /* with current.*, holds local time */
time_t t=time(NULL);
struct tm *tm=gmtime(&t);
current.month=tm->tm_mon+1;
if(tm->tm_mday<current.date) current.month--;
if(current.month<1){ current.month+=12; tm->tm_year--; }
y=year=tm->tm_year;
mon=current.month;
day=current.date;
time2=current.time;
current.time=utc2local((int)current.time, &current.month, &current.date, &y, NULL);
if(latitude!=999 && calcSolarZenith(latitude, longitude, year, mon, day, hm2min(time2))>90)
current.moon=calc_moon(current.month, current.date, y, current.time);
}
return 1;
}
#undef get_substr