libgfortran/intrinsics/date_and_time.c

   1 /* Implementation of the DATE_AND_TIME intrinsic.
   2    Copyright (C) 2003, 2004 Free Software Foundation, Inc.
   3    Contributed by Steven Bosscher.
   4
   5 This file is part of the GNU Fortran 95 runtime library (libgfor).
   6
   7 Libgfor is free software; you can redistribute it and/or
   8 modify it under the terms of the GNU Lesser General Public
   9 License as published by the Free Software Foundation; either
  10 version 2.1 of the License, or (at your option) any later version.
  11
  12 Libgfor is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU Lesser General Public License for more details.
  16
  17 You should have received a copy of the GNU Lesser General Public
  18 License along with libgfor; see the file COPYING.LIB.  If not,
  19 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include <sys/types.h>
  24 #include <string.h>
  25 #include <assert.h>
  26 #include <stdio.h>
  27 #include <stdlib.h>
  28 #include "libgfortran.h"
  29
  30 #undef HAVE_NO_DATE_TIME
  31 #if TIME_WITH_SYS_TIME
  32 #  include <sys/time.h>
  33 #  include <time.h>
  34 #else
  35 #  if HAVE_SYS_TIME_H
  36 #    include <sys/time.h>
  37 #  else
  38 #    ifdef HAVE_TIME_H
  39 #      include <time.h>
  40 #    else
  41 #      define HAVE_NO_DATE_TIME
  42 #    endif  /* HAVE_TIME_H  */
  43 #  endif  /* HAVE_SYS_TIME_H  */
  44 #endif  /* TIME_WITH_SYS_TIME  */
  45
  46 #ifndef abs
  47 #define abs(x) ((x)>=0 ? (x) : -(x))
  48 #endif
  49
  50 /* DATE_AND_TIME ([DATE, TIME, ZONE, VALUES])
  51
  52    Description: Returns data on the real-time clock and date in a form
  53    compatible with the representations defined in ISO 8601:1988.
  54
  55    Class: Non-elemental subroutine.
  56
  57    Arguments:
  58
  59    DATE (optional) shall be scalar and of type default character, and
  60    shall be of length at least 8 in order to contain the complete
  61    value. It is an INTENT (OUT) argument. Its leftmost 8 characters
  62    are assigned a value of the form CCYYMMDD, where CC is the century,
  63    YY the year within the century, MM the month within the year, and
  64    DD the day within the month. If there is no date available, they
  65    are assigned blanks.
  66
  67    TIME (optional) shall be scalar and of type default character, and
  68    shall be of length at least 10 in order to contain the complete
  69    value. It is an INTENT (OUT) argument. Its leftmost 10 characters
  70    are assigned a value of the form hhmmss.sss, where hh is the hour
  71    of the day, mm is the minutes of the hour, and ss.sss is the
  72    seconds and milliseconds of the minute. If there is no clock
  73    available, they are assigned blanks.
  74
  75    ZONE (optional) shall be scalar and of type default character, and
  76    shall be of length at least 5 in order to contain the complete
  77    value. It is an INTENT (OUT) argument. Its leftmost 5 characters
  78    are assigned a value of the form ±hhmm, where hh and mm are the
  79    time difference with respect to Coordinated Universal Time (UTC) in
  80    hours and parts of an hour expressed in minutes, respectively. If
  81    there is no clock available, they are assigned blanks.
  82
  83    VALUES (optional) shall be of type default integer and of rank
  84    one. It is an INTENT (OUT) argument. Its size shall be at least
  85    8. The values returned in VALUES are as follows:
  86
  87       VALUES (1) the year (for example, 2003), or HUGE (0) if there is
  88       no date available;
  89
  90       VALUES (2) the month of the year, or HUGE (0) if there
  91       is no date available;
  92
  93       VALUES (3) the day of the month, or HUGE (0) if there is no date
  94       available;
  95
  96       VALUES (4) the time difference with respect to Coordinated
  97       Universal Time (UTC) in minutes, or HUGE (0) if this information
  98       is not available;
  99
 100       VALUES (5) the hour of the day, in the range of 0 to 23, or HUGE
 101       (0) if there is no clock;
 102
 103       VALUES (6) the minutes of the hour, in the range 0 to 59, or
 104       HUGE (0) if there is no clock;
 105
 106       VALUES (7) the seconds of the minute, in the range 0 to 60, or
 107       HUGE (0) if there is no clock;
 108
 109       VALUES (8) the milliseconds of the second, in the range 0 to
 110       999, or HUGE (0) if there is no clock.
 111
 112    NULL pointer represent missing OPTIONAL arguments.  All arguments
 113    have INTENT(OUT).  Because of the -i8 option, we must implement
 114    VALUES for INTEGER(kind=4) and INTEGER(kind=8).
 115
 116    Based on libU77's date_time_.c.
 117
 118    TODO :
 119    - Check year boundaries.
 120    - There is no STDC/POSIX way to get VALUES(8).  A GNUish way may
 121      be to use ftime.
 122 */
 123
 124 void
 125 date_and_time (char *__date,
 126                char *__time,
 127                char *__zone,
 128                gfc_array_i4 *__values,
 129                GFC_INTEGER_4 __date_len,
 130                GFC_INTEGER_4 __time_len,
 131                GFC_INTEGER_4 __zone_len)
 132 {
 133 #define DATE_LEN 8
 134 #define TIME_LEN 10
 135 #define ZONE_LEN 5
 136 #define VALUES_SIZE 8
 137   char date[DATE_LEN + 1];
 138   char timec[TIME_LEN + 1];
 139   char zone[ZONE_LEN + 1];
 140   GFC_INTEGER_4 values[VALUES_SIZE];
 141
 142 #ifndef HAVE_NO_DATE_TIME
 143   time_t lt = time (NULL);
 144   struct tm local_time = *localtime (&lt);
 145   struct tm UTC_time = *gmtime (&lt);
 146
 147   /* All arguments can be derived from VALUES.  */
 148   values[0] = 1900 + local_time.tm_year;
 149   values[1] = 1 + local_time.tm_mon;
 150   values[2] = local_time.tm_mday;
 151   values[3] = (local_time.tm_min - UTC_time.tm_min +
 152                60 * (local_time.tm_hour - UTC_time.tm_hour +
 153                      24 * (local_time.tm_yday - UTC_time.tm_yday)));
 154   values[4] = local_time.tm_hour;
 155   values[5] = local_time.tm_min;
 156   values[6] = local_time.tm_sec;
 157 #if HAVE_GETTIMEOFDAY
 158     {
 159       struct timeval tp;
 160 #  if GETTIMEOFDAY_ONE_ARGUMENT
 161       if (!gettimeofday (&tp))
 162 #  else
 163 #    if HAVE_STRUCT_TIMEZONE
 164       struct timezone tzp;
 165
 166       /* Some systems such as HP-UX, do have struct timezone, but
 167          gettimeofday takes void* as the 2nd arg.  However, the
 168          effect of passing anything other than a null pointer is
 169          unspecified on HPUX.  Configure checks if gettimeofday
 170          actually fails with a non-NULL arg and pretends that
 171          struct timezone is missing if it does fail.  */
 172       if (!gettimeofday (&tp, &tzp))
 173 #    else
 174       if (!gettimeofday (&tp, (void *) 0))
 175 #    endif /* HAVE_STRUCT_TIMEZONE  */
 176 #  endif /* GETTIMEOFDAY_ONE_ARGUMENT  */
 177         values[7] = tp.tv_usec / 1000;
 178     }
 179 #else
 180    values[7] = GFC_INTEGER_4_HUGE;
 181 #endif /* HAVE_GETTIMEOFDAY */
 182
 183   if (__date)
 184     {
 185       snprintf (date, DATE_LEN + 1, "%04d%02d%02d",
 186                 values[0], values[1], values[2]);
 187     }
 188
 189   if (__time)
 190     {
 191       snprintf (timec, TIME_LEN + 1, "%02d%02d%02d.%03d",
 192                 values[4], values[5], values[6], values[7]);
 193     }
 194
 195   if (__zone)
 196     {
 197       snprintf (zone, ZONE_LEN + 1, "%+03d%02d",
 198                 values[3] / 60, abs (values[3] % 60));
 199     }
 200 #else /* if defined HAVE_NO_DATE_TIME  */
 201   /* We really have *nothing* to return, so return blanks and HUGE(0).  */
 202     {
 203       int i;
 204
 205       memset (date, ' ', DATE_LEN);
 206       date[DATE_LEN] = '\0';
 207
 208       memset (timec, ' ', TIME_LEN);
 209       time[TIME_LEN] = '\0';
 210
 211       memset (zone, ' ', ZONE_LEN);
 212       zone[ZONE_LEN] = '\0';
 213
 214       for (i = 0; i < VALUES_SIZE; i++)
 215         values[i] = GFC_INTEGER_4_HUGE;
 216     }
 217 #endif  /* HAVE_NO_DATE_TIME  */
 218
 219   /* Copy the values into the arguments.  */
 220   if (__values)
 221     {
 222       int i;
 223       size_t len, delta, elt_size;
 224
 225       elt_size = GFC_DESCRIPTOR_SIZE (__values);
 226       len = __values->dim[0].ubound + 1 - __values->dim[0].lbound;
 227       delta = __values->dim[0].stride;
 228       if (delta == 0)
 229         delta = 1;
 230
 231       assert (len >= VALUES_SIZE);
 232       /* Cope with different type kinds.  */
 233       if (elt_size == 4)
 234         {
 235           GFC_INTEGER_4 *vptr4 = __values->data;
 236
 237           for (i = 0; i < VALUES_SIZE; i++, vptr4 += delta)
 238             {
 239               *vptr4 = values[i];
 240             }
 241         }
 242       else if (elt_size == 8)
 243         {
 244           GFC_INTEGER_8 *vptr8 = (GFC_INTEGER_8 *)__values->data;
 245
 246           for (i = 0; i < VALUES_SIZE; i++, vptr8 += delta)
 247             {
 248               if (values[i] == GFC_INTEGER_4_HUGE)
 249                 *vptr8 = GFC_INTEGER_8_HUGE;
 250               else
 251                 *vptr8 = values[i];
 252             }
 253         }
 254       else
 255         abort ();
 256     }
 257
 258   if (__zone)
 259     {
 260       assert (__zone_len >= ZONE_LEN);
 261       fstrcpy (__zone, ZONE_LEN, zone, ZONE_LEN);
 262     }
 263
 264   if (__time)
 265     {
 266       assert (__time_len >= TIME_LEN);
 267       fstrcpy (__time, TIME_LEN, timec, TIME_LEN);
 268     }
 269
 270   if (__date)
 271     {
 272       assert (__date_len >= DATE_LEN);
 273       fstrcpy (__date, DATE_LEN, date, DATE_LEN);
 274     }
 275 #undef DATE_LEN
 276 #undef TIME_LEN
 277 #undef ZONE_LEN
 278 #undef VALUES_SIZE
 279 }