sys/src/cmd/calendar.c

   1 #include <u.h>
   2 #include <libc.h>
   3 #include <bio.h>
   4 #include <regexp.h>
   5 #include <ctype.h>
   6
   7 typedef struct Date     Date;
   8 struct Date {
   9         Reprog *p;      /* an RE to match this date */
  10         Date *next;     /* pointer to next in list */
  11 };
  12
  13 enum{
  14         Secondsperday = 24*60*60
  15 };
  16
  17 Date *Base = nil;
  18 Biobuf in;
  19 int debug, matchyear;
  20
  21 void dates(Tm*);
  22 void upper2lower(char*, char*, int);
  23 void *emalloc(unsigned int);
  24
  25 void
  26 usage(void)
  27 {
  28         fprint(2, "usage: calendar [-dy] [-p days] [files ...]\n");
  29         exits("usage");
  30 }
  31
  32 void
  33 main(int argc, char *argv[])
  34 {
  35         int i, fd, ahead;
  36         long now;
  37         char *line;
  38         Tm *tm;
  39         Date *d;
  40         char buf[1024];
  41
  42         ahead = 0;
  43         ARGBEGIN{
  44         case 'y':
  45                 matchyear = 1;
  46                 break;
  47         case 'd':
  48                 debug = 1;
  49                 break;
  50         case 'p':
  51                 ahead = atoi(EARGF(usage()));
  52                 break;
  53         default:
  54                 usage();
  55         }ARGEND;
  56
  57         /* make a list of dates */
  58         now = time(0);
  59         tm = localtime(now);
  60         dates(tm);
  61         now += Secondsperday;
  62         tm = localtime(now);
  63         dates(tm);
  64         if(tm->wday == 6){
  65                 now += Secondsperday;
  66                 tm = localtime(now);
  67                 dates(tm);
  68         }
  69         if(tm->wday == 0){
  70                 now += Secondsperday;
  71                 tm = localtime(now);
  72                 dates(tm);
  73         }
  74         if(ahead){
  75                 now = time(0);
  76                 now += ahead * Secondsperday;
  77                 tm = localtime(now);
  78                 dates(tm);
  79         }
  80
  81         for(i=0; i<argc || (i==0 && argc==0); i++){
  82                 if(i==0 && argc==0)
  83                         snprint(buf, sizeof buf,
  84                                 "/usr/%s/lib/calendar", getuser());
  85                 else
  86                         strecpy(buf, buf+sizeof buf, argv[i]);
  87                 fd = open(buf, OREAD);
  88                 if(fd<0 || Binit(&in, fd, OREAD)<0){
  89                         fprint(2, "calendar: can't open %s: %r\n", buf);
  90                         exits("open");
  91                 }
  92
  93                 /* go through the file */
  94                 while(line = Brdline(&in, '\n')){
  95                         line[Blinelen(&in) - 1] = 0;
  96                         upper2lower(buf, line, sizeof buf);
  97                         for(d=Base; d; d=d->next)
  98                                 if(regexec(d->p, buf, 0, 0)){
  99                                         print("%s\n", line);
 100                                         break;
 101                                 }
 102                 }
 103                 close(fd);
 104         }
 105         exits("");
 106 }
 107
 108 char *months[] =
 109 {
 110         "january",
 111         "february",
 112         "march",
 113         "april",
 114         "may",
 115         "june",
 116         "july",
 117         "august",
 118         "september",
 119         "october",
 120         "november",
 121         "december"
 122 };
 123 char *nth[] = {
 124         "first",
 125         "second",
 126         "third",
 127         "fourth",
 128         "fifth"
 129 };
 130 char *days[] = {
 131         "sunday",
 132         "monday",
 133         "tuesday",
 134         "wednesday",
 135         "thursday",
 136         "friday",
 137         "saturday"
 138 };
 139
 140 /*
 141  * Generate two Date structures.  First has month followed by day;
 142  * second has day followed by month.  Link them into list after
 143  * last, and return the first.
 144  */
 145 void
 146 dates(Tm *tm)
 147 {
 148         Date *nd;
 149         char mo[128], day[128], buf[128];
 150
 151         if(utflen(days[tm->wday]) > 3)
 152                 snprint(day, sizeof day, "%3.3s(%s)?",
 153                         days[tm->wday], days[tm->wday]+3);
 154         else
 155                 snprint(day, sizeof day, "%3.3s", days[tm->wday]);
 156
 157         if(utflen(months[tm->mon]) > 3)
 158                 snprint(mo, sizeof mo, "%3.3s(%s)?",
 159                         months[tm->mon], months[tm->mon]+3);
 160         else
 161                 snprint(mo, sizeof mo, "%3.3s", months[tm->mon]);
 162         if (matchyear)
 163                 snprint(buf, sizeof buf,
 164                         "^[\t ]*((%s( |\t)+)|(%d/))%d( |\t|$)(((%d|%d|%02d)( |\t|$))|[^0-9]|([0-9]+[^0-9 \t]))",
 165                         mo, tm->mon+1, tm->mday, tm->year+1900, tm->year%100, tm->year%100);
 166         else
 167                 snprint(buf, sizeof buf,
 168                         "^[\t ]*((%s( |\t)+)|(%d/))%d( |\t|$)",
 169                         mo, tm->mon+1, tm->mday);
 170         if(debug)
 171                 print("%s\n", buf);
 172
 173         nd = emalloc(sizeof(Date));
 174         nd->p = regcomp(buf);
 175         nd->next = Base;
 176         Base = nd;
 177
 178         if (matchyear)
 179                 snprint(buf, sizeof buf,
 180                         "^[\t ]*%d( |\t)+(%s)( |\t|$)(((%d|%d|%02d)( |\t|$))|[^0-9]|([0-9]+[^0-9 \t]))",
 181                         tm->mday, mo, tm->year+1900, tm->year%100, tm->year%100);
 182         else
 183                 snprint(buf, sizeof buf,
 184                         "^[\t ]*%d( |\t)+(%s)( |\t|$)",
 185                         tm->mday, mo);
 186         if(debug)
 187                 print("%s\n", buf);
 188         nd = emalloc(sizeof(Date));
 189         nd->p = regcomp(buf);
 190         nd->next = Base;
 191         Base = nd;
 192
 193         snprint(buf, sizeof buf, "^[\t ]*every[ \t]+%s", day);
 194         if(debug)
 195                 print("%s\n", buf);
 196         nd = emalloc(sizeof(Date));
 197         nd->p = regcomp(buf);
 198         nd->next = Base;
 199         Base = nd;
 200
 201         snprint(buf, sizeof buf, "[\t ]*the[\t ]+%s[\t ]+%s", nth[(tm->mday-1)/7], day);
 202         if(debug)
 203                 print("%s\n", buf);
 204         nd = emalloc(sizeof(Date));
 205         nd->p = regcomp(buf);
 206         nd->next = Base;
 207         Base = nd;
 208 }
 209
 210 /*
 211  * Copy 'from' to 'to', converting to lower case
 212  */
 213 void
 214 upper2lower(char *to, char *from, int len)
 215 {
 216         while(--len>0 && *from!='\0')
 217                 *to++ = tolower(*from++);
 218         *to = 0;
 219 }
 220
 221 /*
 222  * Call malloc and check for errors
 223  */
 224 void*
 225 emalloc(unsigned int n)
 226 {
 227         void *p;
 228
 229         p = malloc(n);
 230         if(p == 0){
 231                 fprint(2, "calendar: malloc failed: %r\n");
 232                 exits("malloc");
 233         }
 234         return p;
 235 }