diplodocus.org Git - nmh/blob - docs/historical/mh-jun-1982/Extras/libh/date.c

   1 #ifdef COMMENT
   2         Proprietary Rand Corporation, 1981.
   3         Further distribution of this software
   4         subject to the terms of the Rand
   5         license agreement.
   6 #endif
   7
   8 /** Version of date.c in s1 modified to be a subroutine
   9 *  it is called with a string and returns a pointer to ints.
  10 *  ie,          ip = date(string);
  11 *  returns 0 if it fails.
  12 *  only error message is bad conversion if string is illegal.
  13 *  The only legal format is ########[ps]
  14 *  where the int field is fixed input and 'p' forces PM by adding 12 hours
  15 *  and 's' would force standard savings time
  16 */
  17 int     timbuf[2];
  18 char    *cbp;
  19 int *cpx;
  20 int     dmsize[];
  21 date(string)
  22 char *string;
  23 {
  24         extern int timezone, *localtime();
  25
  26         cbp = string;
  27         if(gtime()) {
  28                 write(2, "bad conversion\n", 15);
  29                 return(0);
  30         }
  31         if (*cbp != 's') {
  32         /* convert to Greenwich time, on assumption of Standard time. */
  33                 dpadd(timbuf, timezone);
  34         /* Now fix up to local daylight time. */
  35                 if ((cpx = localtime(timbuf))[8])
  36                         dpadd(timbuf, -1*60*60);
  37         }
  38         return(timbuf);
  39 }
  40
  41 gtime()
  42 {
  43         register int i;
  44         register int y, t;
  45         int d, h, m;
  46         extern int *localtime();
  47         int nt[2];
  48
  49         t = gpair();
  50         if(t<1 || t>12)
  51                 goto bad;
  52         d = gpair();
  53         if(d<1 || d>31)
  54                 goto bad;
  55         h = gpair();
  56         if(h == 24) {
  57                 h = 0;
  58                 d++;
  59         }
  60         m = gpair();
  61         if(m<0 || m>59)
  62                 goto bad;
  63         y = gpair();
  64         if (y<0) {
  65                 time(nt);
  66                 y = localtime(nt)[5];
  67         }
  68         if (*cbp == 'p')
  69                 h =+ 12;
  70         if (h<0 || h>23)
  71                 goto bad;
  72         timbuf[0] = 0;
  73         timbuf[1] = 0;
  74         y =+ 1900;
  75         for(i=1970; i<y; i++)
  76                 gdadd(dysize(i));
  77         /* Leap year */
  78         if (dysize(y)==366 && t >= 3)
  79                 gdadd(1);
  80         while(--t)
  81                 gdadd(dmsize[t-1]);
  82         gdadd(d-1);
  83         gmdadd(24, h);
  84         gmdadd(60, m);
  85         gmdadd(60, 0);
  86         return(0);
  87
  88 bad:
  89         return(1);
  90 }
  91
  92 gdadd(n)
  93 {
  94         register char *t;
  95
  96         t = timbuf[1]+n;
  97         if(t < timbuf[1])
  98                 timbuf[0]++;
  99         timbuf[1] = t;
 100 }
 101
 102 gmdadd(m, n)
 103 {
 104         register int t1;
 105
 106         timbuf[0] =* m;
 107         t1 = timbuf[1];
 108         while(--m)
 109                 gdadd(t1);
 110         gdadd(n);
 111 }
 112
 113 gpair()
 114 {
 115         register int c, d;
 116         register char *cp;
 117
 118         cp = cbp;
 119         if(*cp == 0)
 120                 return(-1);
 121         c = (*cp++ - '0') * 10;
 122         if (c<0 || c>100)
 123                 return(-1);
 124         if(*cp == 0)
 125                 return(-1);
 126         if ((d = *cp++ - '0') < 0 || d > 9)
 127                 return(-1);
 128         cbp = cp;
 129         return (c+d);
 130 }