src/vmstime.c

   1 /* Time support for VMS.
   2    Copyright (C) 1993 Free Software Foundation.
   3
   4 This file is part of GNU Emacs.
   5
   6 GNU Emacs is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Emacs is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Emacs; see the file COPYING.  If not, write to
  18 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 #include <config.h>
  22 #include "vmstime.h"
  23
  24 long timezone=0;
  25 int daylight=0;
  26
  27 static char tzname_default[20]="";
  28 static char tzname_dst[20]="";
  29
  30 char *tzname[2] = { tzname_default, tzname_dst };
  31
  32 static long internal_daylight=0;
  33 static char daylight_set=0;
  34
  35 static long read_time(const char *nptr, const char **endptr,
  36                       int sign_allowed_p)
  37 {
  38   int t;
  39
  40   *endptr = nptr;
  41
  42   /* This routine trusts the user very much, and does no checks!
  43       The only exception is this: */
  44   if (!sign_allowed_p && (*nptr == '-' || *nptr == '+'))
  45     return 0;
  46
  47   t = strtol(*endptr, endptr, 10) * 3600;
  48   if (**endptr != ':' || **endptr == '+' || **endptr == '-')
  49     return t;
  50   (*endptr)++;
  51
  52   t = t + strtol(*endptr, endptr, 10) * 60;
  53   if (**endptr != ':' || **endptr == '+' || **endptr == '-')
  54     return t;
  55   (*endptr)++;
  56
  57   return t + strtol(*endptr, endptr, 10);
  58 }
  59
  60 static void read_dst_time(const char *nptr, const char **endptr,
  61                           int *m, int *n, int *d,
  62                           int *leap_p)
  63 {
  64   time_t bintim = time(0);
  65   struct tm *lc = localtime(&bintim);
  66
  67   *leap_p = 1;
  68   *m = 0;                       /* When m and n are 0, a Julian */
  69   *n = 0;                       /* date has been inserted in d */
  70
  71   switch(*nptr)
  72     {
  73     case 'M':
  74       {
  75         /* This routine counts on the user to have specified "Mm.n.d",
  76            where 1 <= n <= 5, 1 <= m <= 12, 0 <= d <= 6 */
  77
  78         *m = strtol(++nptr, endptr, 10);
  79         (*endptr)++;            /* Skip the dot */
  80         *n = strtol(*endptr, endptr, 10);
  81         (*endptr)++;            /* Skip the dot */
  82         *d = strtol(*endptr, endptr, 10);
  83
  84         return;
  85       }
  86     case 'J':
  87       *leap_p = 0;              /* Never count with leap years */
  88     default: /* trust the user to have inserted a number! */
  89       *d = strtol(++nptr, endptr, 10);
  90       return;
  91     }
  92 }
  93
  94 struct vms_vectim
  95 {
  96   short year, month, day, hour, minute, second, centi_second;
  97 };
  98 static void find_dst_time(int m, int n, long d,
  99                           int hour, int minute, int second,
 100                           int leap_p,
 101                           long vms_internal_time[2])
 102 {
 103   long status = SYS$GETTIM(vms_internal_time);
 104   struct vms_vectim vms_vectime;
 105   status = SYS$NUMTIM(&vms_vectime, vms_internal_time);
 106
 107   if (m == 0 && n == 0)
 108     {
 109       long tmp_vms_internal_time[2][2];
 110       long day_of_year;
 111       long tmp_operation = LIB$K_DAY_OF_YEAR;
 112
 113       status = LIB$CVT_FROM_INTERNAL_TIME(&tmp_operation, &day_of_year,
 114                                           vms_internal_time);
 115
 116       vms_vectime.month = 2;
 117       vms_vectime.day = 29;
 118       status = LIB$CVT_VECTIM(&vms_vectime, tmp_vms_internal_time[0]);
 119       if (status & 1) /* This is a leap year */
 120         {
 121           if (!leap_p && d > 59)
 122             d ++;               /* If we don't count with 29th Feb,
 123                                    and this is a leap year, count up,
 124                                    to make day 60 really become the
 125                                    1st March. */
 126         }
 127       /* 1st January, at midnight */
 128       vms_vectime.month = 1;
 129       vms_vectime.day = 1;
 130       vms_vectime.hour = hour;
 131       vms_vectime.minute = minute;
 132       vms_vectime.second = second;
 133       vms_vectime.centi_second = 0;
 134       status = LIB$CVT_VECTIM(&vms_vectime, tmp_vms_internal_time[0]);
 135       tmp_operation = LIB$K_DELTA_DAYS;
 136       status = LIB$CVT_TO_INTERNAL_TIME(&tmp_operation, &d,
 137                                         tmp_vms_internal_time[1]);
 138       /* now, tmp_vms_interval_time[0] contains 1st Jan, 00:00:00,
 139          and  tmp_vms_interval_time[1] contains delta time +d days.
 140          Let's just add them together */
 141       status = LIB$ADD_TIMES(tmp_vms_internal_time[0],
 142                              tmp_vms_internal_time[1],
 143                              vms_internal_time);
 144     }
 145   else
 146     {
 147       long tmp_vms_internal_time[2];
 148       long day_of_week;
 149       long tmp_operation = LIB$K_DAY_OF_YEAR;
 150
 151       if (d == 0) /* 0 is Sunday, which isn't compatible with VMS,
 152                      where day_of_week is 1 -- 7, and 1 is Monday */
 153         {
 154           d = 7; /* So a simple conversion is required */
 155         }
 156       vms_vectime.month = m;
 157       vms_vectime.day = 1;
 158       vms_vectime.hour = hour;
 159       vms_vectime.minute = minute;
 160       vms_vectime.second = second;
 161       vms_vectime.centi_second = 0;
 162       status = LIB$CVT_VECTIM(&vms_vectime, tmp_vms_internal_time);
 163       tmp_operation = LIB$K_DAY_OF_WEEK;
 164       status = LIB$CVT_FROM_INTERNAL_TIME(&tmp_operation, &day_of_week,
 165                                           tmp_vms_internal_time);
 166       d -= day_of_week;
 167       if (d < 0)
 168         {
 169           d += 7;
 170         }
 171       vms_vectime.day += (n-1)*7 + d;
 172       status = LIB$CVT_VECTIM(&vms_vectime, vms_internal_time);
 173       if (!(status & 1))
 174         {
 175           vms_vectime.day -= 7; /* n was probably 5 */
 176           status = LIB$CVT_VECTIM(&vms_vectime, vms_internal_time);
 177         }
 178     }
 179 }
 180
 181 static cmp_vms_internal_times(long vms_internal_time1[2],
 182                               long vms_internal_time2[2])
 183 {
 184   if (vms_internal_time1[1] < vms_internal_time2[1])
 185     return -1;
 186   else
 187     if (vms_internal_time1[1] > vms_internal_time2[1])
 188       return 1;
 189
 190   if (vms_internal_time1[0] < vms_internal_time2[0])
 191     return -1;
 192   else
 193     if (vms_internal_time1[0] > vms_internal_time2[0])
 194       return 1;
 195
 196   return 0;
 197 }
 198
 199 /* -------------------------- Global routines ------------------------------ */
 200
 201 #ifdef tzset
 202 #undef tzset
 203 #endif
 204 void sys_tzset()
 205 {
 206   char *TZ;
 207   char *p, *q;
 208
 209   if (daylight_set)
 210     return;
 211
 212   daylight = 0;
 213
 214   if ((TZ = getenv("TZ")) == 0)
 215     return;
 216
 217   p = TZ;
 218   q = tzname[0];
 219
 220   while(*p != '\0'
 221         && (*p <'0' || *p > '9') && *p != '-' && *p != '+' && *p != ',')
 222     *q++ = *p++;
 223   *q = '\0';
 224
 225   /* This is special for VMS, so I don't care if it doesn't exist anywhere
 226      else */
 227
 228   timezone = read_time(p, &p, 1);
 229
 230   q = tzname[1];
 231
 232   while(*p != '\0'
 233         && (*p <'0' || *p > '9') && *p != '-' && *p != '+' && *p != ',')
 234     *q++ = *p++;
 235   *q = '\0';
 236
 237   if (*p != '-' && *p != '+' && !(*p >='0' && *p <= '9'))
 238     internal_daylight = timezone - 3600;
 239   else
 240     internal_daylight = read_time(p, &p, 1);
 241
 242   if (*p == ',')
 243     {
 244       int start_m;
 245       int start_n;
 246       int start_d;
 247       int start_leap_p;
 248       int start_hour=2, start_minute=0, start_second=0;
 249
 250       p++;
 251       read_dst_time(p, &p, &start_m, &start_n, &start_d, &start_leap_p);
 252       if (*p == '/')
 253         {
 254           long tmp = read_time (++p, &p, 0);
 255           start_hour = tmp / 3600;
 256           start_minute = (tmp % 3600) / 60;
 257           start_second = tmp % 60;
 258         }
 259       if (*p == ',')
 260         {
 261           int end_m;
 262           int end_n;
 263           int end_d;
 264           int end_leap_p;
 265           int end_hour=2, end_minute=0, end_second=0;
 266
 267           p++;
 268           read_dst_time(p, &p, &end_m, &end_n, &end_d, &end_leap_p);
 269           if (*p == '/')
 270             {
 271               long tmp = read_time (++p, &p, 0);
 272               end_hour = tmp / 3600;
 273               end_minute = (tmp % 3600) / 60;
 274               end_second = tmp % 60;
 275             }
 276           {
 277             long vms_internal_time[3][2];
 278             find_dst_time(start_m, start_n, start_d,
 279                           start_hour, start_minute, start_second,
 280                           start_leap_p,
 281                           vms_internal_time[0]);
 282             SYS$GETTIM(&vms_internal_time[1]);
 283             find_dst_time(end_m, end_n, end_d,
 284                           end_hour, end_minute, end_second,
 285                           end_leap_p,
 286                           vms_internal_time[2]);
 287             if (cmp_vms_internal_times(vms_internal_time[0],
 288                                       vms_internal_time[1]) < 0
 289                 && cmp_vms_internal_times(vms_internal_time[1],
 290                                          vms_internal_time[2]) < 0)
 291               daylight = 1;
 292           }
 293         }
 294     }
 295 }
 296
 297 #ifdef localtime
 298 #undef localtime
 299 #endif
 300 struct tm *sys_localtime(time_t *clock)
 301 {
 302   struct tm *tmp = localtime(clock);
 303
 304   sys_tzset();
 305   tmp->tm_isdst = daylight;
 306
 307   return tmp;
 308 }
 309
 310 #ifdef gmtime
 311 #undef gmtime
 312 #endif
 313 struct tm *sys_gmtime(time_t *clock)
 314 {
 315   static struct tm gmt;
 316   struct vms_vectim tmp_vectime;
 317   long vms_internal_time[3][2];
 318   long tmp_operation = LIB$K_DELTA_SECONDS;
 319   long status;
 320   long tmp_offset;
 321   char tmp_o_sign;
 322
 323   sys_tzset();
 324
 325   if (daylight)
 326     tmp_offset = internal_daylight;
 327   else
 328     tmp_offset = timezone;
 329
 330   if (tmp_offset < 0)
 331     {
 332       tmp_o_sign = -1;
 333       tmp_offset = -tmp_offset;
 334     }
 335   else
 336     tmp_o_sign = 1;
 337
 338   status = LIB$CVT_TO_INTERNAL_TIME(&tmp_operation, &tmp_offset,
 339                                     vms_internal_time[1]);
 340   status = SYS$GETTIM(vms_internal_time[0]);
 341   if (tmp_o_sign < 0)
 342     {
 343       status = LIB$SUB_TIMES(vms_internal_time[0],
 344                              vms_internal_time[1],
 345                              vms_internal_time[2]);
 346     }
 347   else
 348     {
 349       status = LIB$ADD_TIMES(vms_internal_time[0],
 350                              vms_internal_time[1],
 351                              vms_internal_time[2]);
 352     }
 353
 354   status = SYS$NUMTIM(&tmp_vectime, vms_internal_time[2]);
 355   gmt.tm_sec = tmp_vectime.second;
 356   gmt.tm_min = tmp_vectime.minute;
 357   gmt.tm_hour = tmp_vectime.hour;
 358   gmt.tm_mday = tmp_vectime.day;
 359   gmt.tm_mon = tmp_vectime.month - 1;
 360   gmt.tm_year = tmp_vectime.year - 1900;
 361
 362   tmp_operation = LIB$K_DAY_OF_WEEK;
 363   status = LIB$CVT_FROM_INTERNAL_TIME(&tmp_operation,
 364                                       &gmt.tm_wday,
 365                                       vms_internal_time[2]);
 366   if (gmt.tm_wday == 7) gmt.tm_wday = 0;
 367
 368   tmp_operation = LIB$K_DAY_OF_YEAR;
 369   status = LIB$CVT_FROM_INTERNAL_TIME(&tmp_operation,
 370                                       &gmt.tm_yday,
 371                                       vms_internal_time[2]);
 372   gmt.tm_yday--;
 373   gmt.tm_isdst = daylight;
 374
 375   return &gmt;
 376 }
 377