1/* PO/POT file timestamps.
2   Copyright (C) 1995-1998, 2000-2003 Free Software Foundation, Inc.
3   Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>, April 1995.
4
5   This program is free software; you can redistribute it and/or modify
6   it under the terms of the GNU General Public License as published by
7   the Free Software Foundation; either version 2, or (at your option)
8   any later version.
9
10   This program is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   GNU General Public License for more details.
14
15   You should have received a copy of the GNU General Public License
16   along with this program; if not, write to the Free Software Foundation,
17   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
18
19#ifdef HAVE_CONFIG_H
20# include <config.h>
21#endif
22
23/* Specification.  */
24#include "po-time.h"
25
26#include "xerror.h"
27
28
29#define TM_YEAR_ORIGIN 1900
30
31/* Yield A - B, measured in seconds.  */
32static long
33difftm (const struct tm *a, const struct tm *b)
34{
35  int ay = a->tm_year + TM_YEAR_ORIGIN - 1;
36  int by = b->tm_year + TM_YEAR_ORIGIN - 1;
37  /* Some compilers cannot handle this as a single return statement.  */
38  long days = (
39	       /* difference in day of year  */
40	       a->tm_yday - b->tm_yday
41	       /* + intervening leap days  */
42	       + ((ay >> 2) - (by >> 2))
43	       - (ay / 100 - by / 100)
44	       + ((ay / 100 >> 2) - (by / 100 >> 2))
45	       /* + difference in years * 365  */
46	       + (long) (ay - by) * 365l);
47
48  return 60l * (60l * (24l * days + (a->tm_hour - b->tm_hour))
49	        + (a->tm_min - b->tm_min))
50	 + (a->tm_sec - b->tm_sec);
51}
52
53
54char *
55po_strftime (const time_t *tp)
56{
57  struct tm local_time;
58  char tz_sign;
59  long tz_min;
60
61  local_time = *localtime (tp);
62  tz_sign = '+';
63  tz_min = difftm (&local_time, gmtime (tp)) / 60;
64  if (tz_min < 0)
65    {
66      tz_min = -tz_min;
67      tz_sign = '-';
68    }
69  return xasprintf ("%d-%02d-%02d %02d:%02d%c%02ld%02ld",
70		    local_time.tm_year + TM_YEAR_ORIGIN,
71		    local_time.tm_mon + 1,
72		    local_time.tm_mday,
73		    local_time.tm_hour,
74		    local_time.tm_min,
75		    tz_sign, tz_min / 60, tz_min % 60);
76}
77