lib/timefmt.c

   1 /*
   2    Time formatting functions
   3
   4    Copyright (C) 1994-2022
   5    Free Software Foundation, Inc.
   6
   7    Written by:
   8    Miguel de Icaza, 1994, 1995, 1996
   9    Janne Kukonlehto, 1994, 1995, 1996
  10    Dugan Porter, 1994, 1995, 1996
  11    Jakub Jelinek, 1994, 1995, 1996
  12    Mauricio Plaza, 1994, 1995, 1996
  13
  14    The file_date routine is mostly from GNU's fileutils package,
  15    written by Richard Stallman and David MacKenzie.
  16
  17    This file is part of the Midnight Commander.
  18
  19    The Midnight Commander is free software: you can redistribute it
  20    and/or modify it under the terms of the GNU General Public License as
  21    published by the Free Software Foundation, either version 3 of the License,
  22    or (at your option) any later version.
  23
  24    The Midnight Commander is distributed in the hope that it will be useful,
  25    but WITHOUT ANY WARRANTY; without even the implied warranty of
  26    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27    GNU General Public License for more details.
  28
  29    You should have received a copy of the GNU General Public License
  30    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  31  */
  32
  33 /** \file
  34  *  \brief Source: time formatting functions
  35  */
  36
  37 #include <config.h>
  38
  39 #include <stdlib.h>
  40 #include <limits.h>             /* MB_LEN_MAX */
  41
  42 #include "lib/global.h"
  43 #include "lib/strutil.h"
  44
  45 #include "lib/timefmt.h"
  46
  47 /*** global variables ****************************************************************************/
  48
  49 char *user_recent_timeformat = NULL;    /* time format string for recent dates */
  50 char *user_old_timeformat = NULL;       /* time format string for older dates */
  51
  52 /*** file scope macro definitions ****************************************************************/
  53
  54 /*** file scope type declarations ****************************************************************/
  55
  56 /*** file scope variables ************************************************************************/
  57
  58 /*
  59  * Cache variable for the i18n_checktimelength function,
  60  * initially set to a clearly invalid value to show that
  61  * it hasn't been initialized yet.
  62  */
  63 static size_t i18n_timelength_cache = MAX_I18NTIMELENGTH + 1;
  64
  65 /*** file scope functions ************************************************************************/
  66
  67 /*** public functions ****************************************************************************/
  68
  69 /* --------------------------------------------------------------------------------------------- */
  70 /**
  71  * Check strftime() results. Some systems (i.e. Solaris) have different
  72  *  short-month and month name sizes for different locales
  73  */
  74 size_t
  75 i18n_checktimelength (void)
  76 {
  77     size_t length = 0;
  78     time_t testtime;
  79     struct tm *lt;
  80
  81     if (i18n_timelength_cache <= MAX_I18NTIMELENGTH)
  82         return i18n_timelength_cache;
  83
  84     testtime = time (NULL);
  85     lt = localtime (&testtime);
  86
  87     if (lt == NULL)
  88     {
  89         /* huh, localtime() doesnt seem to work ... falling back to "(invalid)" */
  90         length = str_term_width1 (_(INVALID_TIME_TEXT));
  91     }
  92     else
  93     {
  94         char buf[MB_LEN_MAX * MAX_I18NTIMELENGTH + 1];
  95         size_t tlen;
  96
  97         /* We are interested in the longest possible date */
  98         lt->tm_sec = lt->tm_min = lt->tm_hour = lt->tm_mday = 10;
  99
 100         /* Loop through all months to find out the longest one */
 101         for (lt->tm_mon = 0; lt->tm_mon < 12; lt->tm_mon++)
 102         {
 103             strftime (buf, sizeof (buf) - 1, user_recent_timeformat, lt);
 104             tlen = (size_t) str_term_width1 (buf);
 105             length = MAX (tlen, length);
 106             strftime (buf, sizeof (buf) - 1, user_old_timeformat, lt);
 107             tlen = (size_t) str_term_width1 (buf);
 108             length = MAX (tlen, length);
 109         }
 110
 111         tlen = (size_t) str_term_width1 (_(INVALID_TIME_TEXT));
 112         length = MAX (tlen, length);
 113     }
 114
 115     /* Don't handle big differences. Use standard value (email bug, please) */
 116     if (length > MAX_I18NTIMELENGTH || length < MIN_I18NTIMELENGTH)
 117         length = STD_I18NTIMELENGTH;
 118
 119     /* Save obtained value to the cache */
 120     i18n_timelength_cache = length;
 121
 122     return i18n_timelength_cache;
 123 }
 124
 125 /* --------------------------------------------------------------------------------------------- */
 126
 127 const char *
 128 file_date (time_t when)
 129 {
 130     static char timebuf[MB_LEN_MAX * MAX_I18NTIMELENGTH + 1];
 131     time_t current_time = time (NULL);
 132     const char *fmt;
 133
 134     if (current_time > when + 6L * 30L * 24L * 60L * 60L        /* Old. */
 135         || current_time < when - 60L * 60L)     /* In the future. */
 136         /* The file is fairly old or in the future.
 137            POSIX says the cutoff is 6 months old;
 138            approximate this by 6*30 days.
 139            Allow a 1 hour slop factor for what is considered "the future",
 140            to allow for NFS server/client clock disagreement.
 141            Show the year instead of the time of day.  */
 142
 143         fmt = user_old_timeformat;
 144     else
 145         fmt = user_recent_timeformat;
 146
 147     FMT_LOCALTIME (timebuf, sizeof (timebuf), fmt, when);
 148
 149     return timebuf;
 150 }
 151
 152 /* --------------------------------------------------------------------------------------------- */