sys/src/cmd/date.c

   1 #include <u.h>
   2 #include <libc.h>
   3
   4 static char *day[] = {
   5         "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat",
   6 };
   7
   8 static char *mon[] = {
   9         "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul",
  10         "Aug", "Sep", "Oct", "Nov", "Dec"
  11 };
  12
  13 int uflg, nflg, iflg, tflg, mflg;
  14
  15 char*
  16 isodate(Tm *t)
  17 {
  18         static char c[26]; /* leave room to append isotime */
  19         snprint(c, 11, "%04d-%02d-%02d",
  20                 t->year + 1900, t->mon + 1, t->mday);
  21         return c;
  22 }
  23
  24 char*
  25 isotime(Tm *t)
  26 {
  27         int tz;
  28         char *c, *d;
  29         d = isodate(t);
  30         c = d+10;
  31         snprint(c, 10, "T%02d:%02d:%02d",
  32                 t->hour, t->min, t->sec); /* append to isodate */
  33         tz = t->tzoff / 60;
  34         if(t->tzoff) {
  35                 /* localtime */
  36                 if (t->tzoff > 0) {
  37                         c[9] = '+';
  38                 } else {
  39                         c[9] = '-';
  40                         tz = -tz;
  41                 }
  42                 snprint(c+10, 6, "%02d:%02d", tz / 60, tz % 60);
  43         } else {
  44                 c[9] = 'Z';
  45                 c[10] = 0;
  46         }
  47         return d;
  48 }
  49
  50 char *
  51 mailtime(Tm *t)
  52 {
  53         static char c[64];
  54         char *sgn;
  55         int off;
  56
  57         sgn = "+";
  58         if(t->tzoff < 0)
  59                 sgn = "";
  60         off = (t->tzoff/3600)*100 + (t->tzoff/60)%60;
  61         snprint(c, sizeof(c), "%s, %.2d %s %.4d %.2d:%.2d:%.2d %s%.4d",
  62                 day[t->wday], t->mday, mon[t->mon], t->year + 1900,
  63                 t->hour, t->min, t->sec, sgn, off);
  64         return c;
  65 }
  66
  67 void
  68 main(int argc, char *argv[])
  69 {
  70         ulong now;
  71         Tm *tm;
  72         ARGBEGIN{
  73         case 'n':       nflg = 1; break;
  74         case 'u':       uflg = 1; break;
  75         case 't':       tflg = 1; /* implies -i */
  76         case 'i':       iflg = 1; break;
  77         case 'm':       mflg = 1; break;
  78         default:        fprint(2, "usage: date [-itunm] [seconds]\n"); exits("usage");
  79         }ARGEND
  80
  81         if(argc == 1)
  82                 now = strtoul(*argv, 0, 0);
  83         else
  84                 now = time(0);
  85
  86         if(nflg)
  87                 print("%ld\n", now);
  88         else {
  89                 tm = uflg ? gmtime(now) : localtime(now);
  90                 if(iflg) {
  91                         if(tflg)
  92                                 print("%s\n", isotime(tm));
  93                         else
  94                                 print("%s\n", isodate(tm));
  95                 } else if(mflg)
  96                         print("%s\n", mailtime(tm));
  97                 else
  98                         print("%s", asctime(tm));
  99         }
 100         exits(0);
 101 }