Subversion Repositories planix.SVN

#include <u.h>
#include <libc.h>
#include <bio.h>
#include <regexp.h>
#include <ctype.h>

typedef struct Date     Date;
struct Date {
        Reprog *p;      /* an RE to match this date */
        Date *next;     /* pointer to next in list */
};

enum{
        Secondsperday = 24*60*60
};

Date *Base = nil;
Biobuf in;
int debug, matchyear;

void dates(Tm*);
void upper2lower(char*, char*, int);
void *emalloc(unsigned int);

void
usage(void)
{
        fprint(2, "usage: calendar [-dy] [-p days] [files ...]\n");
        exits("usage");
}

void
main(int argc, char *argv[])
{
        int i, fd, ahead;
        long now;
        char *line;
        Tm *tm;
        Date *d;
        char buf[1024];

        ahead = 0;
        ARGBEGIN{
        case 'y':
                matchyear = 1;
                break;
        case 'd':
                debug = 1;
                break;
        case 'p':
                ahead = atoi(EARGF(usage()));
                break;
        default:
                usage();
        }ARGEND;

        /* make a list of dates */
        now = time(0);
        tm = localtime(now);
        dates(tm);
        now += Secondsperday;
        tm = localtime(now);
        dates(tm);
        if(tm->wday == 6){
                now += Secondsperday;
                tm = localtime(now);
                dates(tm);
        }
        if(tm->wday == 0){
                now += Secondsperday;
                tm = localtime(now);
                dates(tm);
        }
        if(ahead){
                now = time(0);
                now += ahead * Secondsperday;
                tm = localtime(now);
                dates(tm);
        }

        for(i=0; i<argc || (i==0 && argc==0); i++){
                if(i==0 && argc==0)
                        snprint(buf, sizeof buf,
                                "/usr/%s/lib/calendar", getuser());
                else
                        strecpy(buf, buf+sizeof buf, argv[i]);
                fd = open(buf, OREAD);
                if(fd<0 || Binit(&in, fd, OREAD)<0){
                        fprint(2, "calendar: can't open %s: %r\n", buf);
                        exits("open");
                }

                /* go through the file */
                while(line = Brdline(&in, '\n')){
                        line[Blinelen(&in) - 1] = 0;
                        upper2lower(buf, line, sizeof buf);
                        for(d=Base; d; d=d->next)
                                if(regexec(d->p, buf, 0, 0)){
                                        print("%s\n", line);
                                        break;
                                }
                }
                close(fd);
        }
        exits("");
}

char *months[] = 
{
        "january",
        "february",
        "march",
        "april",
        "may",
        "june",
        "july",
        "august",
        "september",
        "october",
        "november",
        "december"
};
char *nth[] = {
        "first", 
        "second",
        "third",
        "fourth",
        "fifth"
};
char *days[] = {
        "sunday",
        "monday",
        "tuesday",
        "wednesday",
        "thursday",
        "friday",
        "saturday"
};

/*
 * Generate two Date structures.  First has month followed by day;
 * second has day followed by month.  Link them into list after
 * last, and return the first.
 */
void
dates(Tm *tm)
{
        Date *nd;
        char mo[128], day[128], buf[128];

        if(utflen(days[tm->wday]) > 3)
                snprint(day, sizeof day, "%3.3s(%s)?",
                        days[tm->wday], days[tm->wday]+3);
        else
                snprint(day, sizeof day, "%3.3s", days[tm->wday]);

        if(utflen(months[tm->mon]) > 3)
                snprint(mo, sizeof mo, "%3.3s(%s)?",
                        months[tm->mon], months[tm->mon]+3);
        else
                snprint(mo, sizeof mo, "%3.3s", months[tm->mon]);
        if (matchyear)
                snprint(buf, sizeof buf,
                        "^[\t ]*((%s( |\t)+)|(%d/))%d( |\t|$)(((%d|%d|%02d)( |\t|$))|[^0-9]|([0-9]+[^0-9 \t]))",
                        mo, tm->mon+1, tm->mday, tm->year+1900, tm->year%100, tm->year%100);
        else
                snprint(buf, sizeof buf,
                        "^[\t ]*((%s( |\t)+)|(%d/))%d( |\t|$)",
                        mo, tm->mon+1, tm->mday);
        if(debug)
                print("%s\n", buf);

        nd = emalloc(sizeof(Date));
        nd->p = regcomp(buf);
        nd->next = Base;        
        Base = nd;

        if (matchyear)
                snprint(buf, sizeof buf,
                        "^[\t ]*%d( |\t)+(%s)( |\t|$)(((%d|%d|%02d)( |\t|$))|[^0-9]|([0-9]+[^0-9 \t]))",
                        tm->mday, mo, tm->year+1900, tm->year%100, tm->year%100);
        else
                snprint(buf, sizeof buf,
                        "^[\t ]*%d( |\t)+(%s)( |\t|$)",
                        tm->mday, mo);
        if(debug)
                print("%s\n", buf);
        nd = emalloc(sizeof(Date));
        nd->p = regcomp(buf);   
        nd->next = Base;        
        Base = nd;

        snprint(buf, sizeof buf, "^[\t ]*every[ \t]+%s", day);
        if(debug)
                print("%s\n", buf);
        nd = emalloc(sizeof(Date));
        nd->p = regcomp(buf);   
        nd->next = Base;        
        Base = nd;

        snprint(buf, sizeof buf, "[\t ]*the[\t ]+%s[\t ]+%s", nth[(tm->mday-1)/7], day);
        if(debug)
                print("%s\n", buf);
        nd = emalloc(sizeof(Date));
        nd->p = regcomp(buf);   
        nd->next = Base;        
        Base = nd;
}

/*
 * Copy 'from' to 'to', converting to lower case
 */
void
upper2lower(char *to, char *from, int len)
{
        while(--len>0 && *from!='\0')
                *to++ = tolower(*from++);
        *to = 0;
}

/*
 * Call malloc and check for errors
 */
void*
emalloc(unsigned int n)
{
        void *p;

        p = malloc(n);
        if(p == 0){
                fprint(2, "calendar: malloc failed: %r\n");
                exits("malloc");
        }
        return p;
}