~drizzle-trunk/drizzle/development

815.1.1 by Monty Taylor
Add timegm which is missing on Solaris.
1
/* Convert a `struct tm' to a time_t value.
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   Copyright (C) 1993-1999, 2002-2005, 2006, 2007 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   Contributed by Paul Eggert <eggert@twinsun.com>.
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   This program is free software; you can redistribute it and/or modify
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   it under the terms of the GNU Lesser General Public License as published by
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   the Free Software Foundation; either version 2, or (at your option)
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   any later version.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public License along
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   with this program; if not, write to the Free Software Foundation,
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   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
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20
/* Define this to have a standalone program to test this implementation of
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   mktime.  */
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/* #define DEBUG 1 */
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24
#ifndef _LIBC
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# include <config.h>
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#endif
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28
/* Assume that leap seconds are possible, unless told otherwise.
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   If the host has a `zic' command with a `-L leapsecondfilename' option,
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   then it supports leap seconds; otherwise it probably doesn't.  */
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#ifndef LEAP_SECONDS_POSSIBLE
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# define LEAP_SECONDS_POSSIBLE 1
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#endif
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#include <time.h>
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37
#include <limits.h>
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#include <string.h>		/* For the real memcpy prototype.  */
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#if DEBUG
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# include <stdio.h>
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# include <stdlib.h>
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/* Make it work even if the system's libc has its own mktime routine.  */
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# define mktime my_mktime
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#endif /* DEBUG */
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/* Shift A right by B bits portably, by dividing A by 2**B and
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   truncating towards minus infinity.  A and B should be free of side
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   effects, and B should be in the range 0 <= B <= INT_BITS - 2, where
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   INT_BITS is the number of useful bits in an int.  GNU code can
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   assume that INT_BITS is at least 32.
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54
   ISO C99 says that A >> B is implementation-defined if A < 0.  Some
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   implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift
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   right in the usual way when A < 0, so SHR falls back on division if
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   ordinary A >> B doesn't seem to be the usual signed shift.  */
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#define SHR(a, b)	\
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  (-1 >> 1 == -1	\
60
   ? (a) >> (b)		\
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   : (a) / (1 << (b)) - ((a) % (1 << (b)) < 0))
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63
/* The extra casts in the following macros work around compiler bugs,
64
   e.g., in Cray C 5.0.3.0.  */
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66
/* True if the arithmetic type T is an integer type.  bool counts as
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   an integer.  */
68
#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
69
70
/* True if negative values of the signed integer type T use two's
71
   complement, ones' complement, or signed magnitude representation,
72
   respectively.  Much GNU code assumes two's complement, but some
73
   people like to be portable to all possible C hosts.  */
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#define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
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#define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
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#define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
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78
/* True if the arithmetic type T is signed.  */
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#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
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81
/* The maximum and minimum values for the integer type T.  These
82
   macros have undefined behavior if T is signed and has padding bits.
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   If this is a problem for you, please let us know how to fix it for
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   your host.  */
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#define TYPE_MINIMUM(t) \
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  ((t) (! TYPE_SIGNED (t) \
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	? (t) 0 \
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	: TYPE_SIGNED_MAGNITUDE (t) \
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	? ~ (t) 0 \
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	: ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
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#define TYPE_MAXIMUM(t) \
92
  ((t) (! TYPE_SIGNED (t) \
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	? (t) -1 \
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	: ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))
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96
#ifndef TIME_T_MIN
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# define TIME_T_MIN TYPE_MINIMUM (time_t)
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#endif
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#ifndef TIME_T_MAX
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# define TIME_T_MAX TYPE_MAXIMUM (time_t)
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#endif
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#define TIME_T_MIDPOINT (SHR (TIME_T_MIN + TIME_T_MAX, 1) + 1)
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104
/* Verify a requirement at compile-time (unlike assert, which is runtime).  */
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#define verify(name, assertion) struct name { char a[(assertion) ? 1 : -1]; }
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107
verify (time_t_is_integer, TYPE_IS_INTEGER (time_t));
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verify (twos_complement_arithmetic, TYPE_TWOS_COMPLEMENT (int));
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/* The code also assumes that signed integer overflow silently wraps
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   around, but this assumption can't be stated without causing a
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   diagnostic on some hosts.  */
112
113
#define EPOCH_YEAR 1970
114
#define TM_YEAR_BASE 1900
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verify (base_year_is_a_multiple_of_100, TM_YEAR_BASE % 100 == 0);
116
117
/* Return 1 if YEAR + TM_YEAR_BASE is a leap year.  */
118
static inline int
119
leapyear (long int year)
120
{
121
  /* Don't add YEAR to TM_YEAR_BASE, as that might overflow.
122
     Also, work even if YEAR is negative.  */
123
  return
124
    ((year & 3) == 0
125
     && (year % 100 != 0
126
	 || ((year / 100) & 3) == (- (TM_YEAR_BASE / 100) & 3)));
127
}
128
129
/* How many days come before each month (0-12).  */
130
#ifndef _LIBC
131
static
132
#endif
133
const unsigned short int __mon_yday[2][13] =
134
  {
135
    /* Normal years.  */
136
    { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334, 365 },
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    /* Leap years.  */
138
    { 0, 31, 60, 91, 121, 152, 182, 213, 244, 274, 305, 335, 366 }
139
  };
140
141
142
#ifndef _LIBC
143
/* Portable standalone applications should supply a <time.h> that
144
   declares a POSIX-compliant localtime_r, for the benefit of older
145
   implementations that lack localtime_r or have a nonstandard one.
146
   See the gnulib time_r module for one way to implement this.  */
147
# undef __localtime_r
148
# define __localtime_r localtime_r
149
# define __mktime_internal mktime_internal
150
#endif
151
152
/* Return an integer value measuring (YEAR1-YDAY1 HOUR1:MIN1:SEC1) -
153
   (YEAR0-YDAY0 HOUR0:MIN0:SEC0) in seconds, assuming that the clocks
154
   were not adjusted between the time stamps.
155
156
   The YEAR values uses the same numbering as TP->tm_year.  Values
157
   need not be in the usual range.  However, YEAR1 must not be less
158
   than 2 * INT_MIN or greater than 2 * INT_MAX.
159
160
   The result may overflow.  It is the caller's responsibility to
161
   detect overflow.  */
162
163
static inline time_t
164
ydhms_diff (long int year1, long int yday1, int hour1, int min1, int sec1,
165
	    int year0, int yday0, int hour0, int min0, int sec0)
166
{
167
  verify (C99_integer_division, -1 / 2 == 0);
168
  verify (long_int_year_and_yday_are_wide_enough,
169
	  INT_MAX <= LONG_MAX / 2 || TIME_T_MAX <= UINT_MAX);
170
171
  /* Compute intervening leap days correctly even if year is negative.
172
     Take care to avoid integer overflow here.  */
173
  int a4 = SHR (year1, 2) + SHR (TM_YEAR_BASE, 2) - ! (year1 & 3);
174
  int b4 = SHR (year0, 2) + SHR (TM_YEAR_BASE, 2) - ! (year0 & 3);
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  int a100 = a4 / 25 - (a4 % 25 < 0);
176
  int b100 = b4 / 25 - (b4 % 25 < 0);
177
  int a400 = SHR (a100, 2);
178
  int b400 = SHR (b100, 2);
179
  int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400);
180
181
  /* Compute the desired time in time_t precision.  Overflow might
182
     occur here.  */
183
  time_t tyear1 = year1;
184
  time_t years = tyear1 - year0;
185
  time_t days = 365 * years + yday1 - yday0 + intervening_leap_days;
186
  time_t hours = 24 * days + hour1 - hour0;
187
  time_t minutes = 60 * hours + min1 - min0;
188
  time_t seconds = 60 * minutes + sec1 - sec0;
189
  return seconds;
190
}
191
192
193
/* Return a time_t value corresponding to (YEAR-YDAY HOUR:MIN:SEC),
194
   assuming that *T corresponds to *TP and that no clock adjustments
195
   occurred between *TP and the desired time.
196
   If TP is null, return a value not equal to *T; this avoids false matches.
197
   If overflow occurs, yield the minimal or maximal value, except do not
198
   yield a value equal to *T.  */
199
static time_t
200
guess_time_tm (long int year, long int yday, int hour, int min, int sec,
201
	       const time_t *t, const struct tm *tp)
202
{
203
  if (tp)
204
    {
205
      time_t d = ydhms_diff (year, yday, hour, min, sec,
206
			     tp->tm_year, tp->tm_yday,
207
			     tp->tm_hour, tp->tm_min, tp->tm_sec);
208
      time_t t1 = *t + d;
209
      if ((t1 < *t) == (TYPE_SIGNED (time_t) ? d < 0 : TIME_T_MAX / 2 < d))
210
	return t1;
211
    }
212
213
  /* Overflow occurred one way or another.  Return the nearest result
214
     that is actually in range, except don't report a zero difference
215
     if the actual difference is nonzero, as that would cause a false
216
     match; and don't oscillate between two values, as that would
217
     confuse the spring-forward gap detector.  */
218
  return (*t < TIME_T_MIDPOINT
219
	  ? (*t <= TIME_T_MIN + 1 ? *t + 1 : TIME_T_MIN)
220
	  : (TIME_T_MAX - 1 <= *t ? *t - 1 : TIME_T_MAX));
221
}
222
223
/* Use CONVERT to convert *T to a broken down time in *TP.
224
   If *T is out of range for conversion, adjust it so that
225
   it is the nearest in-range value and then convert that.  */
226
static struct tm *
227
ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
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		time_t *t, struct tm *tp)
229
{
230
  struct tm *r = convert (t, tp);
231
232
  if (!r && *t)
233
    {
234
      time_t bad = *t;
235
      time_t ok = 0;
236
237
      /* BAD is a known unconvertible time_t, and OK is a known good one.
238
	 Use binary search to narrow the range between BAD and OK until
239
	 they differ by 1.  */
240
      while (bad != ok + (bad < 0 ? -1 : 1))
241
	{
242
	  time_t mid = *t = (bad < 0
243
			     ? bad + ((ok - bad) >> 1)
244
			     : ok + ((bad - ok) >> 1));
245
	  r = convert (t, tp);
246
	  if (r)
247
	    ok = mid;
248
	  else
249
	    bad = mid;
250
	}
251
252
      if (!r && ok)
253
	{
254
	  /* The last conversion attempt failed;
255
	     revert to the most recent successful attempt.  */
256
	  *t = ok;
257
	  r = convert (t, tp);
258
	}
259
    }
260
261
  return r;
262
}
263
264
265
/* Convert *TP to a time_t value, inverting
266
   the monotonic and mostly-unit-linear conversion function CONVERT.
267
   Use *OFFSET to keep track of a guess at the offset of the result,
268
   compared to what the result would be for UTC without leap seconds.
269
   If *OFFSET's guess is correct, only one CONVERT call is needed.
270
   This function is external because it is used also by timegm.c.  */
271
time_t
272
__mktime_internal (struct tm *tp,
273
		   struct tm *(*convert) (const time_t *, struct tm *),
274
		   time_t *offset)
275
{
276
  time_t t, gt, t0, t1, t2;
277
  struct tm tm;
278
279
  /* The maximum number of probes (calls to CONVERT) should be enough
280
     to handle any combinations of time zone rule changes, solar time,
281
     leap seconds, and oscillations around a spring-forward gap.
282
     POSIX.1 prohibits leap seconds, but some hosts have them anyway.  */
283
  int remaining_probes = 6;
284
285
  /* Time requested.  Copy it in case CONVERT modifies *TP; this can
286
     occur if TP is localtime's returned value and CONVERT is localtime.  */
287
  int sec = tp->tm_sec;
288
  int min = tp->tm_min;
289
  int hour = tp->tm_hour;
290
  int mday = tp->tm_mday;
291
  int mon = tp->tm_mon;
292
  int year_requested = tp->tm_year;
293
  int isdst = tp->tm_isdst;
294
295
  /* 1 if the previous probe was DST.  */
296
  int dst2;
297
298
  /* Ensure that mon is in range, and set year accordingly.  */
299
  int mon_remainder = mon % 12;
300
  int negative_mon_remainder = mon_remainder < 0;
301
  int mon_years = mon / 12 - negative_mon_remainder;
302
  long int lyear_requested = year_requested;
303
  long int year = lyear_requested + mon_years;
304
305
  /* The other values need not be in range:
306
     the remaining code handles minor overflows correctly,
307
     assuming int and time_t arithmetic wraps around.
308
     Major overflows are caught at the end.  */
309
310
  /* Calculate day of year from year, month, and day of month.
311
     The result need not be in range.  */
312
  int mon_yday = ((__mon_yday[leapyear (year)]
313
		   [mon_remainder + 12 * negative_mon_remainder])
314
		  - 1);
315
  long int lmday = mday;
316
  long int yday = mon_yday + lmday;
317
318
  time_t guessed_offset = *offset;
319
320
  int sec_requested = sec;
321
322
  if (LEAP_SECONDS_POSSIBLE)
323
    {
324
      /* Handle out-of-range seconds specially,
325
	 since ydhms_tm_diff assumes every minute has 60 seconds.  */
326
      if (sec < 0)
327
	sec = 0;
328
      if (59 < sec)
329
	sec = 59;
330
    }
331
332
  /* Invert CONVERT by probing.  First assume the same offset as last
333
     time.  */
334
335
  t0 = ydhms_diff (year, yday, hour, min, sec,
336
		   EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, - guessed_offset);
337
338
  if (TIME_T_MAX / INT_MAX / 366 / 24 / 60 / 60 < 3)
339
    {
340
      /* time_t isn't large enough to rule out overflows, so check
341
	 for major overflows.  A gross check suffices, since if t0
342
	 has overflowed, it is off by a multiple of TIME_T_MAX -
343
	 TIME_T_MIN + 1.  So ignore any component of the difference
344
	 that is bounded by a small value.  */
345
346
      /* Approximate log base 2 of the number of time units per
347
	 biennium.  A biennium is 2 years; use this unit instead of
348
	 years to avoid integer overflow.  For example, 2 average
349
	 Gregorian years are 2 * 365.2425 * 24 * 60 * 60 seconds,
350
	 which is 63113904 seconds, and rint (log2 (63113904)) is
351
	 26.  */
352
      int ALOG2_SECONDS_PER_BIENNIUM = 26;
353
      int ALOG2_MINUTES_PER_BIENNIUM = 20;
354
      int ALOG2_HOURS_PER_BIENNIUM = 14;
355
      int ALOG2_DAYS_PER_BIENNIUM = 10;
356
      int LOG2_YEARS_PER_BIENNIUM = 1;
357
358
      int approx_requested_biennia =
359
	(SHR (year_requested, LOG2_YEARS_PER_BIENNIUM)
360
	 - SHR (EPOCH_YEAR - TM_YEAR_BASE, LOG2_YEARS_PER_BIENNIUM)
361
	 + SHR (mday, ALOG2_DAYS_PER_BIENNIUM)
362
	 + SHR (hour, ALOG2_HOURS_PER_BIENNIUM)
363
	 + SHR (min, ALOG2_MINUTES_PER_BIENNIUM)
364
	 + (LEAP_SECONDS_POSSIBLE
365
	    ? 0
366
	    : SHR (sec, ALOG2_SECONDS_PER_BIENNIUM)));
367
368
      int approx_biennia = SHR (t0, ALOG2_SECONDS_PER_BIENNIUM);
369
      int diff = approx_biennia - approx_requested_biennia;
370
      int abs_diff = diff < 0 ? - diff : diff;
371
372
      /* IRIX 4.0.5 cc miscaculates TIME_T_MIN / 3: it erroneously
373
	 gives a positive value of 715827882.  Setting a variable
374
	 first then doing math on it seems to work.
375
	 (ghazi@caip.rutgers.edu) */
376
      time_t time_t_max = TIME_T_MAX;
377
      time_t time_t_min = TIME_T_MIN;
378
      time_t overflow_threshold =
379
	(time_t_max / 3 - time_t_min / 3) >> ALOG2_SECONDS_PER_BIENNIUM;
380
381
      if (overflow_threshold < abs_diff)
382
	{
383
	  /* Overflow occurred.  Try repairing it; this might work if
384
	     the time zone offset is enough to undo the overflow.  */
385
	  time_t repaired_t0 = -1 - t0;
386
	  approx_biennia = SHR (repaired_t0, ALOG2_SECONDS_PER_BIENNIUM);
387
	  diff = approx_biennia - approx_requested_biennia;
388
	  abs_diff = diff < 0 ? - diff : diff;
389
	  if (overflow_threshold < abs_diff)
390
	    return -1;
391
	  guessed_offset += repaired_t0 - t0;
392
	  t0 = repaired_t0;
393
	}
394
    }
395
396
  /* Repeatedly use the error to improve the guess.  */
397
398
  for (t = t1 = t2 = t0, dst2 = 0;
399
       (gt = guess_time_tm (year, yday, hour, min, sec, &t,
400
			    ranged_convert (convert, &t, &tm)),
401
	t != gt);
402
       t1 = t2, t2 = t, t = gt, dst2 = tm.tm_isdst != 0)
403
    if (t == t1 && t != t2
404
	&& (tm.tm_isdst < 0
405
	    || (isdst < 0
406
		? dst2 <= (tm.tm_isdst != 0)
407
		: (isdst != 0) != (tm.tm_isdst != 0))))
408
      /* We can't possibly find a match, as we are oscillating
409
	 between two values.  The requested time probably falls
410
	 within a spring-forward gap of size GT - T.  Follow the common
411
	 practice in this case, which is to return a time that is GT - T
412
	 away from the requested time, preferring a time whose
413
	 tm_isdst differs from the requested value.  (If no tm_isdst
414
	 was requested and only one of the two values has a nonzero
415
	 tm_isdst, prefer that value.)  In practice, this is more
416
	 useful than returning -1.  */
417
      goto offset_found;
418
    else if (--remaining_probes == 0)
419
      return -1;
420
421
  /* We have a match.  Check whether tm.tm_isdst has the requested
422
     value, if any.  */
423
  if (isdst != tm.tm_isdst && 0 <= isdst && 0 <= tm.tm_isdst)
424
    {
425
      /* tm.tm_isdst has the wrong value.  Look for a neighboring
426
	 time with the right value, and use its UTC offset.
427
428
	 Heuristic: probe the adjacent timestamps in both directions,
429
	 looking for the desired isdst.  This should work for all real
430
	 time zone histories in the tz database.  */
431
432
      /* Distance between probes when looking for a DST boundary.  In
433
	 tzdata2003a, the shortest period of DST is 601200 seconds
434
	 (e.g., America/Recife starting 2000-10-08 01:00), and the
435
	 shortest period of non-DST surrounded by DST is 694800
436
	 seconds (Africa/Tunis starting 1943-04-17 01:00).  Use the
437
	 minimum of these two values, so we don't miss these short
438
	 periods when probing.  */
439
      int stride = 601200;
440
441
      /* The longest period of DST in tzdata2003a is 536454000 seconds
442
	 (e.g., America/Jujuy starting 1946-10-01 01:00).  The longest
443
	 period of non-DST is much longer, but it makes no real sense
444
	 to search for more than a year of non-DST, so use the DST
445
	 max.  */
446
      int duration_max = 536454000;
447
448
      /* Search in both directions, so the maximum distance is half
449
	 the duration; add the stride to avoid off-by-1 problems.  */
450
      int delta_bound = duration_max / 2 + stride;
451
452
      int delta, direction;
453
454
      for (delta = stride; delta < delta_bound; delta += stride)
455
	for (direction = -1; direction <= 1; direction += 2)
456
	  {
457
	    time_t ot = t + delta * direction;
458
	    if ((ot < t) == (direction < 0))
459
	      {
460
		struct tm otm;
461
		ranged_convert (convert, &ot, &otm);
462
		if (otm.tm_isdst == isdst)
463
		  {
464
		    /* We found the desired tm_isdst.
465
		       Extrapolate back to the desired time.  */
466
		    t = guess_time_tm (year, yday, hour, min, sec, &ot, &otm);
467
		    ranged_convert (convert, &t, &tm);
468
		    goto offset_found;
469
		  }
470
	      }
471
	  }
472
    }
473
474
 offset_found:
475
  *offset = guessed_offset + t - t0;
476
477
  if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec)
478
    {
479
      /* Adjust time to reflect the tm_sec requested, not the normalized value.
480
	 Also, repair any damage from a false match due to a leap second.  */
481
      int sec_adjustment = (sec == 0 && tm.tm_sec == 60) - sec;
482
      t1 = t + sec_requested;
483
      t2 = t1 + sec_adjustment;
484
      if (((t1 < t) != (sec_requested < 0))
485
	  | ((t2 < t1) != (sec_adjustment < 0))
486
	  | ! convert (&t2, &tm))
487
	return -1;
488
      t = t2;
489
    }
490
491
  *tp = tm;
492
  return t;
493
}
494
495
496
/* FIXME: This should use a signed type wide enough to hold any UTC
497
   offset in seconds.  'int' should be good enough for GNU code.  We
498
   can't fix this unilaterally though, as other modules invoke
499
   __mktime_internal.  */
500
static time_t localtime_offset;
501
502
/* Convert *TP to a time_t value.  */
503
time_t
504
mktime (struct tm *tp)
505
{
506
#ifdef _LIBC
507
  /* POSIX.1 8.1.1 requires that whenever mktime() is called, the
508
     time zone names contained in the external variable `tzname' shall
509
     be set as if the tzset() function had been called.  */
510
  __tzset ();
511
#endif
512
513
  return __mktime_internal (tp, __localtime_r, &localtime_offset);
514
}
515
516
#ifdef weak_alias
517
weak_alias (mktime, timelocal)
518
#endif
519
520
#ifdef _LIBC
521
libc_hidden_def (mktime)
522
libc_hidden_weak (timelocal)
523
#endif
524

525
#if DEBUG
526
527
static int
528
not_equal_tm (const struct tm *a, const struct tm *b)
529
{
530
  return ((a->tm_sec ^ b->tm_sec)
531
	  | (a->tm_min ^ b->tm_min)
532
	  | (a->tm_hour ^ b->tm_hour)
533
	  | (a->tm_mday ^ b->tm_mday)
534
	  | (a->tm_mon ^ b->tm_mon)
535
	  | (a->tm_year ^ b->tm_year)
536
	  | (a->tm_yday ^ b->tm_yday)
537
	  | (a->tm_isdst ^ b->tm_isdst));
538
}
539
540
static void
541
print_tm (const struct tm *tp)
542
{
543
  if (tp)
544
    printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
545
	    tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
546
	    tp->tm_hour, tp->tm_min, tp->tm_sec,
547
	    tp->tm_yday, tp->tm_wday, tp->tm_isdst);
548
  else
549
    printf ("0");
550
}
551
552
static int
553
check_result (time_t tk, struct tm tmk, time_t tl, const struct tm *lt)
554
{
555
  if (tk != tl || !lt || not_equal_tm (&tmk, lt))
556
    {
557
      printf ("mktime (");
558
      print_tm (lt);
559
      printf (")\nyields (");
560
      print_tm (&tmk);
561
      printf (") == %ld, should be %ld\n", (long int) tk, (long int) tl);
562
      return 1;
563
    }
564
565
  return 0;
566
}
567
568
int
569
main (int argc, char **argv)
570
{
571
  int status = 0;
572
  struct tm tm, tmk, tml;
573
  struct tm *lt;
574
  time_t tk, tl, tl1;
575
  char trailer;
576
577
  if ((argc == 3 || argc == 4)
578
      && (sscanf (argv[1], "%d-%d-%d%c",
579
		  &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer)
580
	  == 3)
581
      && (sscanf (argv[2], "%d:%d:%d%c",
582
		  &tm.tm_hour, &tm.tm_min, &tm.tm_sec, &trailer)
583
	  == 3))
584
    {
585
      tm.tm_year -= TM_YEAR_BASE;
586
      tm.tm_mon--;
587
      tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]);
588
      tmk = tm;
589
      tl = mktime (&tmk);
590
      lt = localtime (&tl);
591
      if (lt)
592
	{
593
	  tml = *lt;
594
	  lt = &tml;
595
	}
596
      printf ("mktime returns %ld == ", (long int) tl);
597
      print_tm (&tmk);
598
      printf ("\n");
599
      status = check_result (tl, tmk, tl, lt);
600
    }
601
  else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0))
602
    {
603
      time_t from = atol (argv[1]);
604
      time_t by = atol (argv[2]);
605
      time_t to = atol (argv[3]);
606
607
      if (argc == 4)
608
	for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
609
	  {
610
	    lt = localtime (&tl);
611
	    if (lt)
612
	      {
613
		tmk = tml = *lt;
614
		tk = mktime (&tmk);
615
		status |= check_result (tk, tmk, tl, &tml);
616
	      }
617
	    else
618
	      {
619
		printf ("localtime (%ld) yields 0\n", (long int) tl);
620
		status = 1;
621
	      }
622
	    tl1 = tl + by;
623
	    if ((tl1 < tl) != (by < 0))
624
	      break;
625
	  }
626
      else
627
	for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
628
	  {
629
	    /* Null benchmark.  */
630
	    lt = localtime (&tl);
631
	    if (lt)
632
	      {
633
		tmk = tml = *lt;
634
		tk = tl;
635
		status |= check_result (tk, tmk, tl, &tml);
636
	      }
637
	    else
638
	      {
639
		printf ("localtime (%ld) yields 0\n", (long int) tl);
640
		status = 1;
641
	      }
642
	    tl1 = tl + by;
643
	    if ((tl1 < tl) != (by < 0))
644
	      break;
645
	  }
646
    }
647
  else
648
    printf ("Usage:\
649
\t%s YYYY-MM-DD HH:MM:SS [ISDST] # Test given time.\n\
650
\t%s FROM BY TO # Test values FROM, FROM+BY, ..., TO.\n\
651
\t%s FROM BY TO - # Do not test those values (for benchmark).\n",
652
	    argv[0], argv[0], argv[0]);
653
654
  return status;
655
}
656
657
#endif /* DEBUG */
658

659
/*
660
Local Variables:
661
compile-command: "gcc -DDEBUG -Wall -W -O -g mktime.c -o mktime"
662
End:
663
*/