2 Unix SMB/Netbios implementation.
4 time handling functions
5 Copyright (C) Andrew Tridgell 1992-1998
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program 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 General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 This stuff was largely rewritten by Paul Eggert <eggert@twinsun.com>
31 int extra_time_offset = 0;
38 #define TIME_T_MIN ((time_t)0 < (time_t) -1 ? (time_t) 0 \
39 : ~ (time_t) 0 << (sizeof (time_t) * CHAR_BIT - 1))
42 #define TIME_T_MAX (~ (time_t) 0 - TIME_T_MIN)
47 /*******************************************************************
48 a gettimeofday wrapper
49 ********************************************************************/
50 void GetTimeOfDay(struct timeval *tval)
52 #ifdef HAVE_GETTIMEOFDAY_TZ
53 gettimeofday(tval,NULL);
59 #define TM_YEAR_BASE 1900
61 /*******************************************************************
62 yield the difference between *A and *B, in seconds, ignoring leap seconds
63 ********************************************************************/
64 static int tm_diff(struct tm *a, struct tm *b)
66 int ay = a->tm_year + (TM_YEAR_BASE - 1);
67 int by = b->tm_year + (TM_YEAR_BASE - 1);
68 int intervening_leap_days =
69 (ay/4 - by/4) - (ay/100 - by/100) + (ay/400 - by/400);
71 int days = 365*years + intervening_leap_days + (a->tm_yday - b->tm_yday);
72 int hours = 24*days + (a->tm_hour - b->tm_hour);
73 int minutes = 60*hours + (a->tm_min - b->tm_min);
74 int seconds = 60*minutes + (a->tm_sec - b->tm_sec);
79 /*******************************************************************
80 return the UTC offset in seconds west of UTC, or 0 if it cannot be determined
81 ******************************************************************/
82 static int TimeZone(time_t t)
84 struct tm *tm = gmtime(&t);
92 return tm_diff(&tm_utc,tm);
97 /*******************************************************************
98 init the time differences
99 ********************************************************************/
102 serverzone = TimeZone(time(NULL));
104 if ((serverzone % 60) != 0) {
105 DEBUG(1,("WARNING: Your timezone is not a multiple of 1 minute.\n"));
108 DEBUG(4,("Serverzone is %d\n",serverzone));
112 /*******************************************************************
113 return the same value as TimeZone, but it should be more efficient.
115 We keep a table of DST offsets to prevent calling localtime() on each
116 call of this function. This saves a LOT of time on many unixes.
118 Updated by Paul Eggert <eggert@twinsun.com>
119 ********************************************************************/
120 static int TimeZoneFaster(time_t t)
122 static struct dst_table {time_t start,end; int zone;} *tdt, *dst_table = NULL;
123 static int table_size = 0;
127 if (t == 0) t = time(NULL);
129 /* Tunis has a 8 day DST region, we need to be careful ... */
130 #define MAX_DST_WIDTH (365*24*60*60)
131 #define MAX_DST_SKIP (7*24*60*60)
133 for (i=0;i<table_size;i++)
134 if (t >= dst_table[i].start && t <= dst_table[i].end) break;
137 zone = dst_table[i].zone;
142 tdt = (struct dst_table *)Realloc(dst_table,
143 sizeof(dst_table[0])*(i+1));
145 DEBUG(0,("TimeZoneFaster: out of memory!\n"));
146 SAFE_FREE(dst_table);
152 dst_table[i].zone = zone;
153 dst_table[i].start = dst_table[i].end = t;
155 /* no entry will cover more than 6 months */
156 low = t - MAX_DST_WIDTH/2;
160 high = t + MAX_DST_WIDTH/2;
164 /* widen the new entry using two bisection searches */
165 while (low+60*60 < dst_table[i].start) {
166 if (dst_table[i].start - low > MAX_DST_SKIP*2)
167 t = dst_table[i].start - MAX_DST_SKIP;
169 t = low + (dst_table[i].start-low)/2;
170 if (TimeZone(t) == zone)
171 dst_table[i].start = t;
176 while (high-60*60 > dst_table[i].end) {
177 if (high - dst_table[i].end > MAX_DST_SKIP*2)
178 t = dst_table[i].end + MAX_DST_SKIP;
180 t = high - (high-dst_table[i].end)/2;
181 if (TimeZone(t) == zone)
182 dst_table[i].end = t;
187 DEBUG(1,("Added DST entry from %s ",
188 asctime(localtime(&dst_table[i].start))));
189 DEBUG(1,("to %s (%d)\n",asctime(localtime(&dst_table[i].end)),
197 /****************************************************************************
198 return the UTC offset in seconds west of UTC, adjusted for extra time offset
199 **************************************************************************/
200 int TimeDiff(time_t t)
202 return TimeZoneFaster(t) + 60*extra_time_offset;
206 /****************************************************************************
207 return the UTC offset in seconds west of UTC, adjusted for extra time
208 offset, for a local time value. If ut = lt + LocTimeDiff(lt), then
209 lt = ut - TimeDiff(ut), but the converse does not necessarily hold near
210 daylight savings transitions because some local times are ambiguous.
211 LocTimeDiff(t) equals TimeDiff(t) except near daylight savings transitions.
212 +**************************************************************************/
213 static int LocTimeDiff(time_t lte)
215 time_t lt = lte - 60*extra_time_offset;
216 int d = TimeZoneFaster(lt);
219 /* if overflow occurred, ignore all the adjustments so far */
220 if (((lte < lt) ^ (extra_time_offset < 0)) | ((t < lt) ^ (d < 0)))
223 /* now t should be close enough to the true UTC to yield the right answer */
228 /****************************************************************************
229 try to optimise the localtime call, it can be quite expensive on some machines
230 ****************************************************************************/
231 struct tm *LocalTime(time_t *t)
240 #define TIME_FIXUP_CONSTANT (369.0*365.25*24*60*60-(3.0*24*60*60+6.0*60*60))
242 /****************************************************************************
243 interpret an 8 byte "filetime" structure to a time_t
244 It's originally in "100ns units since jan 1st 1601"
246 It appears to be kludge-GMT (at least for file listings). This means
247 its the GMT you get by taking a localtime and adding the
248 serverzone. This is NOT the same as GMT in some cases. This routine
249 converts this to real GMT.
250 ****************************************************************************/
251 time_t nt_time_to_unix(NTTIME *nt)
255 /* The next two lines are a fix needed for the
256 broken SCO compiler. JRA. */
257 time_t l_time_min = TIME_T_MIN;
258 time_t l_time_max = TIME_T_MAX;
260 if (nt->high == 0) return(0);
262 d = ((double)nt->high)*4.0*(double)(1<<30);
263 d += (nt->low&0xFFF00000);
266 /* now adjust by 369 years to make the secs since 1970 */
267 d -= TIME_FIXUP_CONSTANT;
269 if (!(l_time_min <= d && d <= l_time_max))
272 ret = (time_t)(d+0.5);
274 /* this takes us from kludge-GMT to real GMT */
276 ret += LocTimeDiff(ret);
283 /****************************************************************************
284 interprets an nt time into a unix time_t
285 ****************************************************************************/
286 time_t interpret_long_date(char *p)
291 return nt_time_to_unix(&nt);
294 /****************************************************************************
295 put a 8 byte filetime from a time_t
296 This takes real GMT as input and converts to kludge-GMT
297 ****************************************************************************/
298 void unix_to_nt_time(NTTIME *nt, time_t t)
310 nt->low = 0xffffffff;
311 nt->high = 0xffffffff;
315 /* this converts GMT to kludge-GMT */
316 t -= LocTimeDiff(t) - serverzone;
319 d += TIME_FIXUP_CONSTANT;
322 nt->high = (uint32)(d * (1.0/(4.0*(double)(1<<30))));
323 nt->low = (uint32)(d - ((double)nt->high)*4.0*(double)(1<<30));
327 /****************************************************************************
328 take an NTTIME structure, containing high / low time. convert to unix time.
329 lkclXXXX this may need 2 SIVALs not a memcpy. we'll see...
330 ****************************************************************************/
331 void put_long_date(char *p,time_t t)
334 unix_to_nt_time(&nt, t);
336 SIVAL(p, 4, nt.high);
339 /****************************************************************************
340 check if it's a null mtime
341 ****************************************************************************/
342 BOOL null_mtime(time_t mtime)
344 if (mtime == 0 || mtime == 0xFFFFFFFF || mtime == (time_t)-1)
349 /*******************************************************************
350 create a 16 bit dos packed date
351 ********************************************************************/
352 static uint16 make_dos_date1(struct tm *t)
355 ret = (((unsigned)(t->tm_mon+1)) >> 3) | ((t->tm_year-80) << 1);
356 ret = ((ret&0xFF)<<8) | (t->tm_mday | (((t->tm_mon+1) & 0x7) << 5));
360 /*******************************************************************
361 create a 16 bit dos packed time
362 ********************************************************************/
363 static uint16 make_dos_time1(struct tm *t)
366 ret = ((((unsigned)t->tm_min >> 3)&0x7) | (((unsigned)t->tm_hour) << 3));
367 ret = ((ret&0xFF)<<8) | ((t->tm_sec/2) | ((t->tm_min & 0x7) << 5));
371 /*******************************************************************
372 create a 32 bit dos packed date/time from some parameters
373 This takes a GMT time and returns a packed localtime structure
374 ********************************************************************/
375 static uint32 make_dos_date(time_t unixdate)
380 t = LocalTime(&unixdate);
384 ret = make_dos_date1(t);
385 ret = ((ret&0xFFFF)<<16) | make_dos_time1(t);
390 /*******************************************************************
391 put a dos date into a buffer (time/date format)
392 This takes GMT time and puts local time in the buffer
393 ********************************************************************/
394 void put_dos_date(char *buf,int offset,time_t unixdate)
396 uint32 x = make_dos_date(unixdate);
400 /*******************************************************************
401 put a dos date into a buffer (date/time format)
402 This takes GMT time and puts local time in the buffer
403 ********************************************************************/
404 void put_dos_date2(char *buf,int offset,time_t unixdate)
406 uint32 x = make_dos_date(unixdate);
407 x = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16);
411 /*******************************************************************
412 put a dos 32 bit "unix like" date into a buffer. This routine takes
413 GMT and converts it to LOCAL time before putting it (most SMBs assume
414 localtime for this sort of date)
415 ********************************************************************/
416 void put_dos_date3(char *buf,int offset,time_t unixdate)
418 if (!null_mtime(unixdate))
419 unixdate -= TimeDiff(unixdate);
420 SIVAL(buf,offset,unixdate);
423 /*******************************************************************
424 interpret a 32 bit dos packed date/time to some parameters
425 ********************************************************************/
426 static void interpret_dos_date(uint32 date,int *year,int *month,int *day,int *hour,int *minute,int *second)
430 p0=date&0xFF; p1=((date&0xFF00)>>8)&0xFF;
431 p2=((date&0xFF0000)>>16)&0xFF; p3=((date&0xFF000000)>>24)&0xFF;
433 *second = 2*(p0 & 0x1F);
434 *minute = ((p0>>5)&0xFF) + ((p1&0x7)<<3);
435 *hour = (p1>>3)&0xFF;
437 *month = ((p2>>5)&0xFF) + ((p3&0x1)<<3) - 1;
438 *year = ((p3>>1)&0xFF) + 80;
441 /*******************************************************************
442 create a unix date (int GMT) from a dos date (which is actually in
444 ********************************************************************/
445 time_t make_unix_date(void *date_ptr)
451 dos_date = IVAL(date_ptr,0);
453 if (dos_date == 0) return(0);
455 interpret_dos_date(dos_date,&t.tm_year,&t.tm_mon,
456 &t.tm_mday,&t.tm_hour,&t.tm_min,&t.tm_sec);
459 /* mktime() also does the local to GMT time conversion for us */
465 /*******************************************************************
466 like make_unix_date() but the words are reversed
467 ********************************************************************/
468 time_t make_unix_date2(void *date_ptr)
472 x = IVAL(date_ptr,0);
473 x2 = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16);
476 return(make_unix_date((void *)&x));
479 /*******************************************************************
480 create a unix GMT date from a dos date in 32 bit "unix like" format
481 these generally arrive as localtimes, with corresponding DST
482 ******************************************************************/
483 time_t make_unix_date3(void *date_ptr)
485 time_t t = (time_t)IVAL(date_ptr,0);
492 /***************************************************************************
493 return a HTTP/1.0 time string
494 ***************************************************************************/
495 char *http_timestring(time_t t)
498 struct tm *tm = LocalTime(&t);
501 slprintf(buf,sizeof(buf)-1,"%ld seconds since the Epoch",(long)t);
503 #ifndef HAVE_STRFTIME
504 fstrcpy(buf, asctime(tm));
505 if(buf[strlen(buf)-1] == '\n')
506 buf[strlen(buf)-1] = 0;
507 #else /* !HAVE_STRFTIME */
508 strftime(buf, sizeof(buf)-1, "%a, %d %b %Y %H:%M:%S %Z", tm);
509 #endif /* !HAVE_STRFTIME */
515 /****************************************************************************
516 Return the date and time as a string
517 ****************************************************************************/
519 char *timestring(BOOL hires)
521 static fstring TimeBuf;
528 t = (time_t)tp.tv_sec;
537 "%ld.%06ld seconds since the Epoch",
543 "%ld seconds since the Epoch",
549 strftime(TimeBuf,sizeof(TimeBuf)-1,"%Y/%m/%d %H:%M:%S",tm);
550 slprintf(TimeBuf+strlen(TimeBuf),
551 sizeof(TimeBuf)-1 - strlen(TimeBuf),
555 strftime(TimeBuf,100,"%Y/%m/%d %H:%M:%S",tm);
565 fstrcpy(TimeBuf, asctime(tm));
572 /****************************************************************************
573 return the best approximation to a 'create time' under UNIX from a stat
575 ****************************************************************************/
577 time_t get_create_time(SMB_STRUCT_STAT *st,BOOL fake_dirs)
581 if(S_ISDIR(st->st_mode) && fake_dirs)
582 return (time_t)315493200L; /* 1/1/1980 */
584 ret = MIN(st->st_ctime, st->st_mtime);
585 ret1 = MIN(ret, st->st_atime);
587 if(ret1 != (time_t)0)
591 * One of ctime, mtime or atime was zero (probably atime).
592 * Just return MIN(ctime, mtime).
597 /****************************************************************************
598 initialise an NTTIME to -1, which means "unknown" or "don't expire"
599 ****************************************************************************/
601 void init_nt_time(NTTIME *nt)
603 nt->high = 0x7FFFFFFF;
604 nt->low = 0xFFFFFFFF;