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;
33 extern int DEBUGLEVEL;
40 #define TIME_T_MIN ((time_t)0 < (time_t) -1 ? (time_t) 0 \
41 : ~ (time_t) 0 << (sizeof (time_t) * CHAR_BIT - 1))
44 #define TIME_T_MAX (~ (time_t) 0 - TIME_T_MIN)
49 /*******************************************************************
50 a gettimeofday wrapper
51 ********************************************************************/
52 void GetTimeOfDay(struct timeval *tval)
54 #ifdef HAVE_GETTIMEOFDAY_TZ
55 gettimeofday(tval,NULL);
61 #define TM_YEAR_BASE 1900
63 /*******************************************************************
64 yield the difference between *A and *B, in seconds, ignoring leap seconds
65 ********************************************************************/
66 static int tm_diff(struct tm *a, struct tm *b)
68 int ay = a->tm_year + (TM_YEAR_BASE - 1);
69 int by = b->tm_year + (TM_YEAR_BASE - 1);
70 int intervening_leap_days =
71 (ay/4 - by/4) - (ay/100 - by/100) + (ay/400 - by/400);
73 int days = 365*years + intervening_leap_days + (a->tm_yday - b->tm_yday);
74 int hours = 24*days + (a->tm_hour - b->tm_hour);
75 int minutes = 60*hours + (a->tm_min - b->tm_min);
76 int seconds = 60*minutes + (a->tm_sec - b->tm_sec);
81 /*******************************************************************
82 return the UTC offset in seconds west of UTC, or 0 if it cannot be determined
83 ******************************************************************/
84 static int TimeZone(time_t t)
86 struct tm *tm = gmtime(&t);
94 return tm_diff(&tm_utc,tm);
99 /*******************************************************************
100 init the time differences
101 ********************************************************************/
104 serverzone = TimeZone(time(NULL));
106 if ((serverzone % 60) != 0) {
107 DEBUG(1,("WARNING: Your timezone is not a multiple of 1 minute.\n"));
110 DEBUG(4,("Serverzone is %d\n",serverzone));
114 /*******************************************************************
115 return the same value as TimeZone, but it should be more efficient.
117 We keep a table of DST offsets to prevent calling localtime() on each
118 call of this function. This saves a LOT of time on many unixes.
120 Updated by Paul Eggert <eggert@twinsun.com>
121 ********************************************************************/
122 static int TimeZoneFaster(time_t t)
124 static struct dst_table {time_t start,end; int zone;} *tdt, *dst_table = NULL;
125 static int table_size = 0;
129 if (t == 0) t = time(NULL);
131 /* Tunis has a 8 day DST region, we need to be careful ... */
132 #define MAX_DST_WIDTH (365*24*60*60)
133 #define MAX_DST_SKIP (7*24*60*60)
135 for (i=0;i<table_size;i++)
136 if (t >= dst_table[i].start && t <= dst_table[i].end) break;
139 zone = dst_table[i].zone;
144 tdt = (struct dst_table *)Realloc(dst_table,
145 sizeof(dst_table[0])*(i+1));
147 DEBUG(0,("TimeZoneFaster: out of memory!\n"));
148 SAFE_FREE(dst_table);
154 dst_table[i].zone = zone;
155 dst_table[i].start = dst_table[i].end = t;
157 /* no entry will cover more than 6 months */
158 low = t - MAX_DST_WIDTH/2;
162 high = t + MAX_DST_WIDTH/2;
166 /* widen the new entry using two bisection searches */
167 while (low+60*60 < dst_table[i].start) {
168 if (dst_table[i].start - low > MAX_DST_SKIP*2)
169 t = dst_table[i].start - MAX_DST_SKIP;
171 t = low + (dst_table[i].start-low)/2;
172 if (TimeZone(t) == zone)
173 dst_table[i].start = t;
178 while (high-60*60 > dst_table[i].end) {
179 if (high - dst_table[i].end > MAX_DST_SKIP*2)
180 t = dst_table[i].end + MAX_DST_SKIP;
182 t = high - (high-dst_table[i].end)/2;
183 if (TimeZone(t) == zone)
184 dst_table[i].end = t;
189 DEBUG(1,("Added DST entry from %s ",
190 asctime(localtime(&dst_table[i].start))));
191 DEBUG(1,("to %s (%d)\n",asctime(localtime(&dst_table[i].end)),
199 /****************************************************************************
200 return the UTC offset in seconds west of UTC, adjusted for extra time offset
201 **************************************************************************/
202 int TimeDiff(time_t t)
204 return TimeZoneFaster(t) + 60*extra_time_offset;
208 /****************************************************************************
209 return the UTC offset in seconds west of UTC, adjusted for extra time
210 offset, for a local time value. If ut = lt + LocTimeDiff(lt), then
211 lt = ut - TimeDiff(ut), but the converse does not necessarily hold near
212 daylight savings transitions because some local times are ambiguous.
213 LocTimeDiff(t) equals TimeDiff(t) except near daylight savings transitions.
214 +**************************************************************************/
215 static int LocTimeDiff(time_t lte)
217 time_t lt = lte - 60*extra_time_offset;
218 int d = TimeZoneFaster(lt);
221 /* if overflow occurred, ignore all the adjustments so far */
222 if (((lte < lt) ^ (extra_time_offset < 0)) | ((t < lt) ^ (d < 0)))
225 /* now t should be close enough to the true UTC to yield the right answer */
230 /****************************************************************************
231 try to optimise the localtime call, it can be quite expensive on some machines
232 ****************************************************************************/
233 struct tm *LocalTime(time_t *t)
242 #define TIME_FIXUP_CONSTANT (369.0*365.25*24*60*60-(3.0*24*60*60+6.0*60*60))
244 /****************************************************************************
245 interpret an 8 byte "filetime" structure to a time_t
246 It's originally in "100ns units since jan 1st 1601"
248 It appears to be kludge-GMT (at least for file listings). This means
249 its the GMT you get by taking a localtime and adding the
250 serverzone. This is NOT the same as GMT in some cases. This routine
251 converts this to real GMT.
252 ****************************************************************************/
253 time_t nt_time_to_unix(NTTIME *nt)
257 /* The next two lines are a fix needed for the
258 broken SCO compiler. JRA. */
259 time_t l_time_min = TIME_T_MIN;
260 time_t l_time_max = TIME_T_MAX;
262 if (nt->high == 0) return(0);
264 d = ((double)nt->high)*4.0*(double)(1<<30);
265 d += (nt->low&0xFFF00000);
268 /* now adjust by 369 years to make the secs since 1970 */
269 d -= TIME_FIXUP_CONSTANT;
271 if (!(l_time_min <= d && d <= l_time_max))
274 ret = (time_t)(d+0.5);
276 /* this takes us from kludge-GMT to real GMT */
278 ret += LocTimeDiff(ret);
285 /****************************************************************************
286 interprets an nt time into a unix time_t
287 ****************************************************************************/
288 time_t interpret_long_date(char *p)
293 return nt_time_to_unix(&nt);
296 /****************************************************************************
297 put a 8 byte filetime from a time_t
298 This takes real GMT as input and converts to kludge-GMT
299 ****************************************************************************/
300 void unix_to_nt_time(NTTIME *nt, time_t t)
312 nt->low = 0xffffffff;
313 nt->high = 0xffffffff;
317 /* this converts GMT to kludge-GMT */
318 t -= LocTimeDiff(t) - serverzone;
321 d += TIME_FIXUP_CONSTANT;
324 nt->high = (uint32)(d * (1.0/(4.0*(double)(1<<30))));
325 nt->low = (uint32)(d - ((double)nt->high)*4.0*(double)(1<<30));
329 /****************************************************************************
330 take an NTTIME structure, containing high / low time. convert to unix time.
331 lkclXXXX this may need 2 SIVALs not a memcpy. we'll see...
332 ****************************************************************************/
333 void put_long_date(char *p,time_t t)
336 unix_to_nt_time(&nt, t);
338 SIVAL(p, 4, nt.high);
341 /****************************************************************************
342 check if it's a null mtime
343 ****************************************************************************/
344 BOOL null_mtime(time_t mtime)
346 if (mtime == 0 || mtime == 0xFFFFFFFF || mtime == (time_t)-1)
351 /*******************************************************************
352 create a 16 bit dos packed date
353 ********************************************************************/
354 static uint16 make_dos_date1(struct tm *t)
357 ret = (((unsigned)(t->tm_mon+1)) >> 3) | ((t->tm_year-80) << 1);
358 ret = ((ret&0xFF)<<8) | (t->tm_mday | (((t->tm_mon+1) & 0x7) << 5));
362 /*******************************************************************
363 create a 16 bit dos packed time
364 ********************************************************************/
365 static uint16 make_dos_time1(struct tm *t)
368 ret = ((((unsigned)t->tm_min >> 3)&0x7) | (((unsigned)t->tm_hour) << 3));
369 ret = ((ret&0xFF)<<8) | ((t->tm_sec/2) | ((t->tm_min & 0x7) << 5));
373 /*******************************************************************
374 create a 32 bit dos packed date/time from some parameters
375 This takes a GMT time and returns a packed localtime structure
376 ********************************************************************/
377 static uint32 make_dos_date(time_t unixdate)
382 t = LocalTime(&unixdate);
386 ret = make_dos_date1(t);
387 ret = ((ret&0xFFFF)<<16) | make_dos_time1(t);
392 /*******************************************************************
393 put a dos date into a buffer (time/date format)
394 This takes GMT time and puts local time in the buffer
395 ********************************************************************/
396 void put_dos_date(char *buf,int offset,time_t unixdate)
398 uint32 x = make_dos_date(unixdate);
402 /*******************************************************************
403 put a dos date into a buffer (date/time format)
404 This takes GMT time and puts local time in the buffer
405 ********************************************************************/
406 void put_dos_date2(char *buf,int offset,time_t unixdate)
408 uint32 x = make_dos_date(unixdate);
409 x = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16);
413 /*******************************************************************
414 put a dos 32 bit "unix like" date into a buffer. This routine takes
415 GMT and converts it to LOCAL time before putting it (most SMBs assume
416 localtime for this sort of date)
417 ********************************************************************/
418 void put_dos_date3(char *buf,int offset,time_t unixdate)
420 if (!null_mtime(unixdate))
421 unixdate -= TimeDiff(unixdate);
422 SIVAL(buf,offset,unixdate);
425 /*******************************************************************
426 interpret a 32 bit dos packed date/time to some parameters
427 ********************************************************************/
428 static void interpret_dos_date(uint32 date,int *year,int *month,int *day,int *hour,int *minute,int *second)
432 p0=date&0xFF; p1=((date&0xFF00)>>8)&0xFF;
433 p2=((date&0xFF0000)>>16)&0xFF; p3=((date&0xFF000000)>>24)&0xFF;
435 *second = 2*(p0 & 0x1F);
436 *minute = ((p0>>5)&0xFF) + ((p1&0x7)<<3);
437 *hour = (p1>>3)&0xFF;
439 *month = ((p2>>5)&0xFF) + ((p3&0x1)<<3) - 1;
440 *year = ((p3>>1)&0xFF) + 80;
443 /*******************************************************************
444 create a unix date (int GMT) from a dos date (which is actually in
446 ********************************************************************/
447 time_t make_unix_date(void *date_ptr)
453 dos_date = IVAL(date_ptr,0);
455 if (dos_date == 0) return(0);
457 interpret_dos_date(dos_date,&t.tm_year,&t.tm_mon,
458 &t.tm_mday,&t.tm_hour,&t.tm_min,&t.tm_sec);
461 /* mktime() also does the local to GMT time conversion for us */
467 /*******************************************************************
468 like make_unix_date() but the words are reversed
469 ********************************************************************/
470 time_t make_unix_date2(void *date_ptr)
474 x = IVAL(date_ptr,0);
475 x2 = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16);
478 return(make_unix_date((void *)&x));
481 /*******************************************************************
482 create a unix GMT date from a dos date in 32 bit "unix like" format
483 these generally arrive as localtimes, with corresponding DST
484 ******************************************************************/
485 time_t make_unix_date3(void *date_ptr)
487 time_t t = (time_t)IVAL(date_ptr,0);
494 /***************************************************************************
495 return a HTTP/1.0 time string
496 ***************************************************************************/
497 char *http_timestring(time_t t)
500 struct tm *tm = LocalTime(&t);
503 slprintf(buf,sizeof(buf)-1,"%ld seconds since the Epoch",(long)t);
505 #ifndef HAVE_STRFTIME
506 fstrcpy(buf, asctime(tm));
507 if(buf[strlen(buf)-1] == '\n')
508 buf[strlen(buf)-1] = 0;
509 #else /* !HAVE_STRFTIME */
510 strftime(buf, sizeof(buf)-1, "%a, %d %b %Y %H:%M:%S %Z", tm);
511 #endif /* !HAVE_STRFTIME */
517 /****************************************************************************
518 Return the date and time as a string
519 ****************************************************************************/
521 char *timestring(BOOL hires)
523 static fstring TimeBuf;
530 t = (time_t)tp.tv_sec;
539 "%ld.%06ld seconds since the Epoch",
545 "%ld seconds since the Epoch",
551 strftime(TimeBuf,sizeof(TimeBuf)-1,"%Y/%m/%d %H:%M:%S",tm);
552 slprintf(TimeBuf+strlen(TimeBuf),
553 sizeof(TimeBuf)-1 - strlen(TimeBuf),
557 strftime(TimeBuf,100,"%Y/%m/%d %H:%M:%S",tm);
567 fstrcpy(TimeBuf, asctime(tm));
574 /****************************************************************************
575 return the best approximation to a 'create time' under UNIX from a stat
577 ****************************************************************************/
579 time_t get_create_time(SMB_STRUCT_STAT *st,BOOL fake_dirs)
583 if(S_ISDIR(st->st_mode) && fake_dirs)
584 return (time_t)315493200L; /* 1/1/1980 */
586 ret = MIN(st->st_ctime, st->st_mtime);
587 ret1 = MIN(ret, st->st_atime);
589 if(ret1 != (time_t)0)
593 * One of ctime, mtime or atime was zero (probably atime).
594 * Just return MIN(ctime, mtime).
599 /****************************************************************************
600 initialise an NTTIME to -1, which means "unknown" or "don't expire"
601 ****************************************************************************/
603 void init_nt_time(NTTIME *nt)
605 nt->high = 0x7FFFFFFF;
606 nt->low = 0xFFFFFFFF;