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 "libgfortran.h"
  27
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30
  31 #undef HAVE_NO_DATE_TIME
  32 #if TIME_WITH_SYS_TIME
  33 #  include <sys/time.h>
  34 #  include <time.h>
  35 #else
  36 #  if HAVE_SYS_TIME_H
  37 #    include <sys/time.h>
  38 #  else
  39 #    ifdef HAVE_TIME_H
  40 #      include <time.h>
  41 #    else
  42 #      define HAVE_NO_DATE_TIME
  43 #    endif  /* HAVE_TIME_H  */
  44 #  endif  /* HAVE_SYS_TIME_H  */
  45 #endif  /* TIME_WITH_SYS_TIME  */
  46
  47 #ifndef abs
  48 #define abs(x) ((x)>=0 ? (x) : -(x))
  49 #endif
  50
  51 /* DATE_AND_TIME ([DATE, TIME, ZONE, VALUES])
  52
  53    Description: Returns data on the real-time clock and date in a form
  54    compatible with the representations defined in ISO 8601:1988.
  55
  56    Class: Non-elemental subroutine.
  57
  58    Arguments:
  59
  60    DATE (optional) shall be scalar and of type default character, and
  61    shall be of length at least 8 in order to contain the complete
  62    value. It is an INTENT (OUT) argument. Its leftmost 8 characters
  63    are assigned a value of the form CCYYMMDD, where CC is the century,
  64    YY the year within the century, MM the month within the year, and
  65    DD the day within the month. If there is no date available, they
  66    are assigned blanks.
  67
  68    TIME (optional) shall be scalar and of type default character, and
  69    shall be of length at least 10 in order to contain the complete
  70    value. It is an INTENT (OUT) argument. Its leftmost 10 characters
  71    are assigned a value of the form hhmmss.sss, where hh is the hour
  72    of the day, mm is the minutes of the hour, and ss.sss is the
  73    seconds and milliseconds of the minute. If there is no clock
  74    available, they are assigned blanks.
  75
  76    ZONE (optional) shall be scalar and of type default character, and
  77    shall be of length at least 5 in order to contain the complete
  78    value. It is an INTENT (OUT) argument. Its leftmost 5 characters
  79    are assigned a value of the form ±hhmm, where hh and mm are the
  80    time difference with respect to Coordinated Universal Time (UTC) in
  81    hours and parts of an hour expressed in minutes, respectively. If
  82    there is no clock available, they are assigned blanks.
  83
  84    VALUES (optional) shall be of type default integer and of rank
  85    one. It is an INTENT (OUT) argument. Its size shall be at least
  86    8. The values returned in VALUES are as follows:
  87
  88       VALUES (1) the year (for example, 2003), or HUGE (0) if there is
  89       no date available;
  90
  91       VALUES (2) the month of the year, or HUGE (0) if there
  92       is no date available;
  93
  94       VALUES (3) the day of the month, or HUGE (0) if there is no date
  95       available;
  96
  97       VALUES (4) the time difference with respect to Coordinated
  98       Universal Time (UTC) in minutes, or HUGE (0) if this information
  99       is not available;
 100
 101       VALUES (5) the hour of the day, in the range of 0 to 23, or HUGE
 102       (0) if there is no clock;
 103
 104       VALUES (6) the minutes of the hour, in the range 0 to 59, or
 105       HUGE (0) if there is no clock;
 106
 107       VALUES (7) the seconds of the minute, in the range 0 to 60, or
 108       HUGE (0) if there is no clock;
 109
 110       VALUES (8) the milliseconds of the second, in the range 0 to
 111       999, or HUGE (0) if there is no clock.
 112
 113    NULL pointer represent missing OPTIONAL arguments.  All arguments
 114    have INTENT(OUT).  Because of the -i8 option, we must implement
 115    VALUES for INTEGER(kind=4) and INTEGER(kind=8).
 116
 117    Based on libU77's date_time_.c.
 118
 119    TODO :
 120    - Check year boundaries.
 121    - There is no STDC/POSIX way to get VALUES(8).  A GNUish way may
 122      be to use ftime.
 123 */
 124
 125 void
 126 date_and_time (char *__date,
 127                char *__time,
 128                char *__zone,
 129                gfc_array_i4 *__values,
 130                GFC_INTEGER_4 __date_len,
 131                GFC_INTEGER_4 __time_len,
 132                GFC_INTEGER_4 __zone_len)
 133 {
 134 #define DATE_LEN 8
 135 #define TIME_LEN 10
 136 #define ZONE_LEN 5
 137 #define VALUES_SIZE 8
 138   char date[DATE_LEN + 1];
 139   char timec[TIME_LEN + 1];
 140   char zone[ZONE_LEN + 1];
 141   GFC_INTEGER_4 values[VALUES_SIZE];
 142
 143 #ifndef HAVE_NO_DATE_TIME
 144   time_t lt = time (NULL);
 145   struct tm local_time = *localtime (&lt);
 146   struct tm UTC_time = *gmtime (&lt);
 147
 148   /* All arguments can be derived from VALUES.  */
 149   values[0] = 1900 + local_time.tm_year;
 150   values[1] = 1 + local_time.tm_mon;
 151   values[2] = local_time.tm_mday;
 152   values[3] = (local_time.tm_min - UTC_time.tm_min +
 153                60 * (local_time.tm_hour - UTC_time.tm_hour +
 154                      24 * (local_time.tm_yday - UTC_time.tm_yday)));
 155   values[4] = local_time.tm_hour;
 156   values[5] = local_time.tm_min;
 157   values[6] = local_time.tm_sec;
 158 #if HAVE_GETTIMEOFDAY
 159     {
 160       struct timeval tp;
 161 #  if GETTIMEOFDAY_ONE_ARGUMENT
 162       if (!gettimeofday (&tp))
 163 #  else
 164 #    if HAVE_STRUCT_TIMEZONE
 165       struct timezone tzp;
 166
 167       /* Some systems such as HP-UX, do have struct timezone, but
 168          gettimeofday takes void* as the 2nd arg.  However, the
 169          effect of passing anything other than a null pointer is
 170          unspecified on HPUX.  Configure checks if gettimeofday
 171          actually fails with a non-NULL arg and pretends that
 172          struct timezone is missing if it does fail.  */
 173       if (!gettimeofday (&tp, &tzp))
 174 #    else
 175       if (!gettimeofday (&tp, (void *) 0))
 176 #    endif /* HAVE_STRUCT_TIMEZONE  */
 177 #  endif /* GETTIMEOFDAY_ONE_ARGUMENT  */
 178         values[7] = tp.tv_usec / 1000;
 179     }
 180 #else
 181    values[7] = GFC_INTEGER_4_HUGE;
 182 #endif /* HAVE_GETTIMEOFDAY */
 183
 184   if (__date)
 185     {
 186       snprintf (date, DATE_LEN + 1, "%04d%02d%02d",
 187                 values[0], values[1], values[2]);
 188     }
 189
 190   if (__time)
 191     {
 192       snprintf (timec, TIME_LEN + 1, "%02d%02d%02d.%03d",
 193                 values[4], values[5], values[6], values[7]);
 194     }
 195
 196   if (__zone)
 197     {
 198       snprintf (zone, ZONE_LEN + 1, "%+03d%02d",
 199                 values[3] / 60, abs (values[3] % 60));
 200     }
 201 #else /* if defined HAVE_NO_DATE_TIME  */
 202   /* We really have *nothing* to return, so return blanks and HUGE(0).  */
 203     {
 204       int i;
 205
 206       memset (date, ' ', DATE_LEN);
 207       date[DATE_LEN] = '\0';
 208
 209       memset (timec, ' ', TIME_LEN);
 210       time[TIME_LEN] = '\0';
 211
 212       memset (zone, ' ', ZONE_LEN);
 213       zone[ZONE_LEN] = '\0';
 214
 215       for (i = 0; i < VALUES_SIZE; i++)
 216         values[i] = GFC_INTEGER_4_HUGE;
 217     }
 218 #endif  /* HAVE_NO_DATE_TIME  */
 219
 220   /* Copy the values into the arguments.  */
 221   if (__values)
 222     {
 223       int i;
 224       size_t len, delta, elt_size;
 225
 226       elt_size = GFC_DESCRIPTOR_SIZE (__values);
 227       len = __values->dim[0].ubound + 1 - __values->dim[0].lbound;
 228       delta = __values->dim[0].stride;
 229       if (delta == 0)
 230         delta = 1;
 231
 232       assert (len >= VALUES_SIZE);
 233       /* Cope with different type kinds.  */
 234       if (elt_size == 4)
 235         {
 236           GFC_INTEGER_4 *vptr4 = __values->data;
 237
 238           for (i = 0; i < VALUES_SIZE; i++, vptr4 += delta)
 239             {
 240               *vptr4 = values[i];
 241             }
 242         }
 243       else if (elt_size == 8)
 244         {
 245           GFC_INTEGER_8 *vptr8 = (GFC_INTEGER_8 *)__values->data;
 246
 247           for (i = 0; i < VALUES_SIZE; i++, vptr8 += delta)
 248             {
 249               if (values[i] == GFC_INTEGER_4_HUGE)
 250                 *vptr8 = GFC_INTEGER_8_HUGE;
 251               else
 252                 *vptr8 = values[i];
 253             }
 254         }
 255       else
 256         abort ();
 257     }
 258
 259   if (__zone)
 260     {
 261       assert (__zone_len >= ZONE_LEN);
 262       fstrcpy (__zone, ZONE_LEN, zone, ZONE_LEN);
 263     }
 264
 265   if (__time)
 266     {
 267       assert (__time_len >= TIME_LEN);
 268       fstrcpy (__time, TIME_LEN, timec, TIME_LEN);
 269     }
 270
 271   if (__date)
 272     {
 273       assert (__date_len >= DATE_LEN);
 274       fstrcpy (__date, DATE_LEN, date, DATE_LEN);
 275     }
 276 #undef DATE_LEN
 277 #undef TIME_LEN
 278 #undef ZONE_LEN
 279 #undef VALUES_SIZE
 280 }