/* Unix SMB/Netbios implementation. Version 1.9. time handling functions Copyright (C) Andrew Tridgell 1992-1998 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 of the License, 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include "includes.h" /* This stuff was largely rewritten by Paul Eggert <eggert@twinsun.com> in May 1996 */ int serverzone=0; int extra_time_offset = 0; extern int DEBUGLEVEL; #ifndef CHAR_BIT #define CHAR_BIT 8 #endif #ifndef TIME_T_MIN #define TIME_T_MIN ((time_t)0 < (time_t) -1 ? (time_t) 0 \ : ~ (time_t) 0 << (sizeof (time_t) * CHAR_BIT - 1)) #endif #ifndef TIME_T_MAX #define TIME_T_MAX (~ (time_t) 0 - TIME_T_MIN) #endif /******************************************************************* a gettimeofday wrapper ********************************************************************/ void GetTimeOfDay(struct timeval *tval) { #ifdef HAVE_GETTIMEOFDAY_TZ gettimeofday(tval,NULL); #else gettimeofday(tval); #endif } #define TM_YEAR_BASE 1900 /******************************************************************* yield the difference between *A and *B, in seconds, ignoring leap seconds ********************************************************************/ static int tm_diff(struct tm *a, struct tm *b) { int ay = a->tm_year + (TM_YEAR_BASE - 1); int by = b->tm_year + (TM_YEAR_BASE - 1); int intervening_leap_days = (ay/4 - by/4) - (ay/100 - by/100) + (ay/400 - by/400); int years = ay - by; int days = 365*years + intervening_leap_days + (a->tm_yday - b->tm_yday); int hours = 24*days + (a->tm_hour - b->tm_hour); int minutes = 60*hours + (a->tm_min - b->tm_min); int seconds = 60*minutes + (a->tm_sec - b->tm_sec); return seconds; } /******************************************************************* return the UTC offset in seconds west of UTC, or 0 if it cannot be determined ******************************************************************/ static int TimeZone(time_t t) { struct tm *tm = gmtime(&t); struct tm tm_utc; if (!tm) return 0; tm_utc = *tm; tm = localtime(&t); if (!tm) return 0; return tm_diff(&tm_utc,tm); } /******************************************************************* init the time differences ********************************************************************/ void TimeInit(void) { serverzone = TimeZone(time(NULL)); if ((serverzone % 60) != 0) { DEBUG(1,("WARNING: Your timezone is not a multiple of 1 minute.\n")); } DEBUG(4,("Serverzone is %d\n",serverzone)); } /******************************************************************* return the same value as TimeZone, but it should be more efficient. We keep a table of DST offsets to prevent calling localtime() on each call of this function. This saves a LOT of time on many unixes. Updated by Paul Eggert <eggert@twinsun.com> ********************************************************************/ static int TimeZoneFaster(time_t t) { static struct dst_table {time_t start,end; int zone;} *dst_table = NULL; static int table_size = 0; int i; int zone = 0; if (t == 0) t = time(NULL); /* Tunis has a 8 day DST region, we need to be careful ... */ #define MAX_DST_WIDTH (365*24*60*60) #define MAX_DST_SKIP (7*24*60*60) for (i=0;i<table_size;i++) if (t >= dst_table[i].start && t <= dst_table[i].end) break; if (i<table_size) { zone = dst_table[i].zone; } else { time_t low,high; zone = TimeZone(t); dst_table = (struct dst_table *)Realloc(dst_table, sizeof(dst_table[0])*(i+1)); if (!dst_table) { table_size = 0; } else { table_size++; dst_table[i].zone = zone; dst_table[i].start = dst_table[i].end = t; /* no entry will cover more than 6 months */ low = t - MAX_DST_WIDTH/2; if (t < low) low = TIME_T_MIN; high = t + MAX_DST_WIDTH/2; if (high < t) high = TIME_T_MAX; /* widen the new entry using two bisection searches */ while (low+60*60 < dst_table[i].start) { if (dst_table[i].start - low > MAX_DST_SKIP*2) t = dst_table[i].start - MAX_DST_SKIP; else t = low + (dst_table[i].start-low)/2; if (TimeZone(t) == zone) dst_table[i].start = t; else low = t; } while (high-60*60 > dst_table[i].end) { if (high - dst_table[i].end > MAX_DST_SKIP*2) t = dst_table[i].end + MAX_DST_SKIP; else t = high - (high-dst_table[i].end)/2; if (TimeZone(t) == zone) dst_table[i].end = t; else high = t; } #if 0 DEBUG(1,("Added DST entry from %s ", asctime(localtime(&dst_table[i].start)))); DEBUG(1,("to %s (%d)\n",asctime(localtime(&dst_table[i].end)), dst_table[i].zone)); #endif } } return zone; } /**************************************************************************** return the UTC offset in seconds west of UTC, adjusted for extra time offset **************************************************************************/ int TimeDiff(time_t t) { return TimeZoneFaster(t) + 60*extra_time_offset; } /**************************************************************************** return the UTC offset in seconds west of UTC, adjusted for extra time offset, for a local time value. If ut = lt + LocTimeDiff(lt), then lt = ut - TimeDiff(ut), but the converse does not necessarily hold near daylight savings transitions because some local times are ambiguous. LocTimeDiff(t) equals TimeDiff(t) except near daylight savings transitions. +**************************************************************************/ static int LocTimeDiff(time_t lte) { time_t lt = lte - 60*extra_time_offset; int d = TimeZoneFaster(lt); time_t t = lt + d; /* if overflow occurred, ignore all the adjustments so far */ if (((lte < lt) ^ (extra_time_offset < 0)) | ((t < lt) ^ (d < 0))) t = lte; /* now t should be close enough to the true UTC to yield the right answer */ return TimeDiff(t); } /**************************************************************************** try to optimise the localtime call, it can be quite expensive on some machines ****************************************************************************/ struct tm *LocalTime(time_t *t) { time_t t2 = *t; t2 -= TimeDiff(t2); return(gmtime(&t2)); } #define TIME_FIXUP_CONSTANT (369.0*365.25*24*60*60-(3.0*24*60*60+6.0*60*60)) /**************************************************************************** interpret an 8 byte "filetime" structure to a time_t It's originally in "100ns units since jan 1st 1601" It appears to be kludge-GMT (at least for file listings). This means its the GMT you get by taking a localtime and adding the serverzone. This is NOT the same as GMT in some cases. This routine converts this to real GMT. ****************************************************************************/ time_t nt_time_to_unix(NTTIME *nt) { double d; time_t ret; /* The next two lines are a fix needed for the broken SCO compiler. JRA. */ time_t l_time_min = TIME_T_MIN; time_t l_time_max = TIME_T_MAX; if (nt->high == 0) return(0); d = ((double)nt->high)*4.0*(double)(1<<30); d += (nt->low&0xFFF00000); d *= 1.0e-7; /* now adjust by 369 years to make the secs since 1970 */ d -= TIME_FIXUP_CONSTANT; if (!(l_time_min <= d && d <= l_time_max)) return(0); ret = (time_t)(d+0.5); /* this takes us from kludge-GMT to real GMT */ ret -= serverzone; ret += LocTimeDiff(ret); return(ret); } /**************************************************************************** interprets an nt time into a unix time_t ****************************************************************************/ time_t interpret_long_date(char *p) { NTTIME nt; nt.low = IVAL(p,0); nt.high = IVAL(p,4); return nt_time_to_unix(&nt); } /**************************************************************************** put a 8 byte filetime from a time_t This takes real GMT as input and converts to kludge-GMT ****************************************************************************/ void unix_to_nt_time(NTTIME *nt, time_t t) { double d; if (t==0) { nt->low = 0; nt->high = 0; return; } /* this converts GMT to kludge-GMT */ t -= LocTimeDiff(t) - serverzone; d = (double)(t); d += TIME_FIXUP_CONSTANT; d *= 1.0e7; nt->high = (uint32)(d * (1.0/(4.0*(double)(1<<30)))); nt->low = (uint32)(d - ((double)nt->high)*4.0*(double)(1<<30)); } /**************************************************************************** take an NTTIME structure, containing high / low time. convert to unix time. lkclXXXX this may need 2 SIVALs not a memcpy. we'll see... ****************************************************************************/ void put_long_date(char *p,time_t t) { NTTIME nt; unix_to_nt_time(&nt, t); SIVAL(p, 0, nt.low); SIVAL(p, 4, nt.high); } /**************************************************************************** check if it's a null mtime ****************************************************************************/ BOOL null_mtime(time_t mtime) { if (mtime == 0 || mtime == 0xFFFFFFFF || mtime == (time_t)-1) return(True); return(False); } /******************************************************************* create a 16 bit dos packed date ********************************************************************/ static uint16 make_dos_date1(struct tm *t) { uint16 ret=0; ret = (((unsigned)(t->tm_mon+1)) >> 3) | ((t->tm_year-80) << 1); ret = ((ret&0xFF)<<8) | (t->tm_mday | (((t->tm_mon+1) & 0x7) << 5)); return(ret); } /******************************************************************* create a 16 bit dos packed time ********************************************************************/ static uint16 make_dos_time1(struct tm *t) { uint16 ret=0; ret = ((((unsigned)t->tm_min >> 3)&0x7) | (((unsigned)t->tm_hour) << 3)); ret = ((ret&0xFF)<<8) | ((t->tm_sec/2) | ((t->tm_min & 0x7) << 5)); return(ret); } /******************************************************************* create a 32 bit dos packed date/time from some parameters This takes a GMT time and returns a packed localtime structure ********************************************************************/ static uint32 make_dos_date(time_t unixdate) { struct tm *t; uint32 ret=0; t = LocalTime(&unixdate); if (!t) return 0xFFFFFFFF; ret = make_dos_date1(t); ret = ((ret&0xFFFF)<<16) | make_dos_time1(t); return(ret); } /******************************************************************* put a dos date into a buffer (time/date format) This takes GMT time and puts local time in the buffer ********************************************************************/ void put_dos_date(char *buf,int offset,time_t unixdate) { uint32 x = make_dos_date(unixdate); SIVAL(buf,offset,x); } /******************************************************************* put a dos date into a buffer (date/time format) This takes GMT time and puts local time in the buffer ********************************************************************/ void put_dos_date2(char *buf,int offset,time_t unixdate) { uint32 x = make_dos_date(unixdate); x = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16); SIVAL(buf,offset,x); } /******************************************************************* put a dos 32 bit "unix like" date into a buffer. This routine takes GMT and converts it to LOCAL time before putting it (most SMBs assume localtime for this sort of date) ********************************************************************/ void put_dos_date3(char *buf,int offset,time_t unixdate) { if (!null_mtime(unixdate)) unixdate -= TimeDiff(unixdate); SIVAL(buf,offset,unixdate); } /******************************************************************* interpret a 32 bit dos packed date/time to some parameters ********************************************************************/ static void interpret_dos_date(uint32 date,int *year,int *month,int *day,int *hour,int *minute,int *second) { uint32 p0,p1,p2,p3; p0=date&0xFF; p1=((date&0xFF00)>>8)&0xFF; p2=((date&0xFF0000)>>16)&0xFF; p3=((date&0xFF000000)>>24)&0xFF; *second = 2*(p0 & 0x1F); *minute = ((p0>>5)&0xFF) + ((p1&0x7)<<3); *hour = (p1>>3)&0xFF; *day = (p2&0x1F); *month = ((p2>>5)&0xFF) + ((p3&0x1)<<3) - 1; *year = ((p3>>1)&0xFF) + 80; } /******************************************************************* create a unix date (int GMT) from a dos date (which is actually in localtime) ********************************************************************/ time_t make_unix_date(void *date_ptr) { uint32 dos_date=0; struct tm t; time_t ret; dos_date = IVAL(date_ptr,0); if (dos_date == 0) return(0); interpret_dos_date(dos_date,&t.tm_year,&t.tm_mon, &t.tm_mday,&t.tm_hour,&t.tm_min,&t.tm_sec); t.tm_isdst = -1; /* mktime() also does the local to GMT time conversion for us */ ret = mktime(&t); return(ret); } /******************************************************************* like make_unix_date() but the words are reversed ********************************************************************/ time_t make_unix_date2(void *date_ptr) { uint32 x,x2; x = IVAL(date_ptr,0); x2 = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16); SIVAL(&x,0,x2); return(make_unix_date((void *)&x)); } /******************************************************************* create a unix GMT date from a dos date in 32 bit "unix like" format these generally arrive as localtimes, with corresponding DST ******************************************************************/ time_t make_unix_date3(void *date_ptr) { time_t t = (time_t)IVAL(date_ptr,0); if (!null_mtime(t)) t += LocTimeDiff(t); return(t); } /*************************************************************************** return a HTTP/1.0 time string ***************************************************************************/ char *http_timestring(time_t t) { static fstring buf; struct tm *tm = LocalTime(&t); if (!tm) slprintf(buf,sizeof(buf)-1,"%ld seconds since the Epoch",(long)t); else #ifndef HAVE_STRFTIME fstrcpy(buf, asctime(tm)); #else /* !HAVE_STRFTIME */ strftime(buf, sizeof(buf)-1, "%a, %d %b %Y %H:%M:%S %Z", tm); #endif /* !HAVE_STRFTIME */ return buf; } /**************************************************************************** return the date and time as a string ****************************************************************************/ char *timestring(void ) { static fstring TimeBuf; time_t t = time(NULL); struct tm *tm = LocalTime(&t); if (!tm) { slprintf(TimeBuf,sizeof(TimeBuf)-1,"%ld seconds since the Epoch",(long)t); } else { #ifdef HAVE_STRFTIME strftime(TimeBuf,100,"%Y/%m/%d %T",tm); #else fstrcpy(TimeBuf, asctime(tm)); #endif } return(TimeBuf); } /**************************************************************************** return the best approximation to a 'create time' under UNIX from a stat structure. ****************************************************************************/ time_t get_create_time(SMB_STRUCT_STAT *st,BOOL fake_dirs) { time_t ret, ret1; if(S_ISDIR(st->st_mode) && fake_dirs) return (time_t)315493200L; /* 1/1/1980 */ ret = MIN(st->st_ctime, st->st_mtime); ret1 = MIN(ret, st->st_atime); if(ret1 != (time_t)0) return ret1; /* * One of ctime, mtime or atime was zero (probably atime). * Just return MIN(ctime, mtime). */ return ret; }