source: trunk/coreutils/src/date.c@ 2555

/* date - print or set the system date and time
   Copyright (C) 1989-2006 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

   David MacKenzie <[email protected]> */

#include <config.h>
#include <stdio.h>
#include <getopt.h>
#include <sys/types.h>
#if HAVE_LANGINFO_CODESET
# include <langinfo.h>
#endif

#include "system.h"
#include "argmatch.h"
#include "error.h"
#include "getdate.h"
#include "getline.h"
#include "inttostr.h"
#include "posixtm.h"
#include "quote.h"
#include "stat-time.h"
#include "fprintftime.h"

/* The official name of this program (e.g., no `g' prefix).  */
#define PROGRAM_NAME "date"

#define AUTHORS "David MacKenzie"

int putenv ();

static bool show_date (const char *format, struct timespec when);

enum Time_spec
{
  /* Display only the date.  */
  TIME_SPEC_DATE,
  /* Display date, hours, minutes, and seconds.  */
  TIME_SPEC_SECONDS,
  /* Similar, but display nanoseconds. */
  TIME_SPEC_NS,

  /* Put these last, since they aren't valid for --rfc-3339.  */

  /* Display date and hour.  */
  TIME_SPEC_HOURS,
  /* Display date, hours, and minutes.  */
  TIME_SPEC_MINUTES
};

static char const *const time_spec_string[] =
{
  /* Put "hours" and "minutes" first, since they aren't valid for
     --rfc-3339.  */
  "hours", "minutes",
  "date", "seconds", "ns", NULL
};
static enum Time_spec const time_spec[] =
{
  TIME_SPEC_HOURS, TIME_SPEC_MINUTES,
  TIME_SPEC_DATE, TIME_SPEC_SECONDS, TIME_SPEC_NS
};
ARGMATCH_VERIFY (time_spec_string, time_spec);

/* A format suitable for Internet RFC 2822.  */
static char const rfc_2822_format[] = "%a, %d %b %Y %H:%M:%S %z";

/* The name this program was run with, for error messages. */
char *program_name;

/* For long options that have no equivalent short option, use a
   non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
enum
{
  RFC_3339_OPTION = CHAR_MAX + 1
};

static char const short_options[] = "d:f:I::r:Rs:u";

static struct option const long_options[] =
{
  {"date", required_argument, NULL, 'd'},
  {"file", required_argument, NULL, 'f'},
  {"iso-8601", optional_argument, NULL, 'I'}, /* Deprecated.  */
  {"reference", required_argument, NULL, 'r'},
  {"rfc-822", no_argument, NULL, 'R'},
  {"rfc-2822", no_argument, NULL, 'R'},
  {"rfc-3339", required_argument, NULL, RFC_3339_OPTION},
  {"set", required_argument, NULL, 's'},
  {"uct", no_argument, NULL, 'u'},
  {"utc", no_argument, NULL, 'u'},
  {"universal", no_argument, NULL, 'u'},
  {GETOPT_HELP_OPTION_DECL},
  {GETOPT_VERSION_OPTION_DECL},
  {NULL, 0, NULL, 0}
};

#if LOCALTIME_CACHE
# define TZSET tzset ()
#else
# define TZSET /* empty */
#endif

#ifdef _DATE_FMT
# define DATE_FMT_LANGINFO() nl_langinfo (_DATE_FMT)
#else
# define DATE_FMT_LANGINFO() ""
#endif

void
usage (int status)
{
  if (status != EXIT_SUCCESS)
    fprintf (stderr, _("Try `%s --help' for more information.\n"),
             program_name);
  else
    {
      printf (_("\
Usage: %s [OPTION]... [+FORMAT]\n\
  or:  %s [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]\n\
"),
              program_name, program_name);
      fputs (_("\
Display the current time in the given FORMAT, or set the system date.\n\
\n\
  -d, --date=STRING         display time described by STRING, not `now'\n\
  -f, --file=DATEFILE       like --date once for each line of DATEFILE\n\
"), stdout);
      fputs (_("\
  -r, --reference=FILE      display the last modification time of FILE\n\
  -R, --rfc-2822            output date and time in RFC 2822 format\n\
      --rfc-3339=TIMESPEC   output date and time in RFC 3339 format.\n\
                            TIMESPEC=`date', `seconds', or `ns' for\n\
                            date and time to the indicated precision.\n\
  -s, --set=STRING          set time described by STRING\n\
  -u, --utc, --universal    print or set Coordinated Universal Time\n\
"), stdout);
      fputs (HELP_OPTION_DESCRIPTION, stdout);
      fputs (VERSION_OPTION_DESCRIPTION, stdout);
      fputs (_("\
\n\
FORMAT controls the output.  The only valid option for the second form\n\
specifies Coordinated Universal Time.  Interpreted sequences are:\n\
\n\
  %%   a literal %\n\
  %a   locale's abbreviated weekday name (e.g., Sun)\n\
"), stdout);
      fputs (_("\
  %A   locale's full weekday name (e.g., Sunday)\n\
  %b   locale's abbreviated month name (e.g., Jan)\n\
  %B   locale's full month name (e.g., January)\n\
  %c   locale's date and time (e.g., Thu Mar  3 23:05:25 2005)\n\
"), stdout);
      fputs (_("\
  %C   century; like %Y, except omit last two digits (e.g., 21)\n\
  %d   day of month (e.g, 01)\n\
  %D   date; same as %m/%d/%y\n\
  %e   day of month, space padded; same as %_d\n\
"), stdout);
      fputs (_("\
  %F   full date; same as %Y-%m-%d\n\
  %g   last two digits of year of ISO week number (see %G)\n\
  %G   year of ISO week number (see %V); normally useful only with %V\n\
"), stdout);
      fputs (_("\
  %h   same as %b\n\
  %H   hour (00..23)\n\
  %I   hour (01..12)\n\
  %j   day of year (001..366)\n\
"), stdout);
      fputs (_("\
  %k   hour ( 0..23)\n\
  %l   hour ( 1..12)\n\
  %m   month (01..12)\n\
  %M   minute (00..59)\n\
"), stdout);
      fputs (_("\
  %n   a newline\n\
  %N   nanoseconds (000000000..999999999)\n\
  %p   locale's equivalent of either AM or PM; blank if not known\n\
  %P   like %p, but lower case\n\
  %r   locale's 12-hour clock time (e.g., 11:11:04 PM)\n\
  %R   24-hour hour and minute; same as %H:%M\n\
  %s   seconds since 1970-01-01 00:00:00 UTC\n\
"), stdout);
      fputs (_("\
  %S   second (00..60)\n\
  %t   a tab\n\
  %T   time; same as %H:%M:%S\n\
  %u   day of week (1..7); 1 is Monday\n\
"), stdout);
      fputs (_("\
  %U   week number of year, with Sunday as first day of week (00..53)\n\
  %V   ISO week number, with Monday as first day of week (01..53)\n\
  %w   day of week (0..6); 0 is Sunday\n\
  %W   week number of year, with Monday as first day of week (00..53)\n\
"), stdout);
      fputs (_("\
  %x   locale's date representation (e.g., 12/31/99)\n\
  %X   locale's time representation (e.g., 23:13:48)\n\
  %y   last two digits of year (00..99)\n\
  %Y   year\n\
"), stdout);
      fputs (_("\
  %z   +hhmm numeric timezone (e.g., -0400)\n\
  %:z  +hh:mm numeric timezone (e.g., -04:00)\n\
  %::z  +hh:mm:ss numeric time zone (e.g., -04:00:00)\n\
  %:::z  numeric time zone with : to necessary precision (e.g., -04, +05:30)\n\
  %Z   alphabetic time zone abbreviation (e.g., EDT)\n\
\n\
By default, date pads numeric fields with zeroes.\n\
The following optional flags may follow `%':\n\
\n\
  - (hyphen) do not pad the field\n\
  _ (underscore) pad with spaces\n\
  0 (zero) pad with zeros\n\
  ^ use upper case if possible\n\
  # use opposite case if possible\n\
"), stdout);
      fputs (_("\
\n\
After any flags comes an optional field width, as a decimal number;\n\
then an optional modifier, which is either\n\
E to use the locale's alternate representations if available, or\n\
O to use the locale's alternate numeric symbols if available.\n\
"), stdout);
      printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
    }
  exit (status);
}

/* Parse each line in INPUT_FILENAME as with --date and display each
   resulting time and date.  If the file cannot be opened, tell why
   then exit.  Issue a diagnostic for any lines that cannot be parsed.
   Return true if successful.  */

static bool
batch_convert (const char *input_filename, const char *format)
{
  bool ok;
  FILE *in_stream;
  char *line;
  size_t buflen;
  struct timespec when;

  if (STREQ (input_filename, "-"))
    {
      input_filename = _("standard input");
      in_stream = stdin;
    }
  else
    {