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Diffstat (limited to 'source/lib/time.c')
| -rw-r--r-- | source/lib/time.c | 495 |
1 files changed, 495 insertions, 0 deletions
diff --git a/source/lib/time.c b/source/lib/time.c new file mode 100644 index 00000000000..0b6e6df9b07 --- /dev/null +++ b/source/lib/time.c @@ -0,0 +1,495 @@ +/* + Unix SMB/Netbios implementation. + Version 1.9. + time handling functions + Copyright (C) Andrew Tridgell 1992-1995 + + 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 (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 GETTIMEOFDAY1 + gettimeofday(tval); +#else + gettimeofday(tval,NULL); +#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 + ******************************************************************/ +static int TimeZone(time_t t) +{ + struct tm tm_utc = *(gmtime(&t)); + return tm_diff(&tm_utc,localtime(&t)); +} + + +/******************************************************************* +init the time differences +********************************************************************/ +void TimeInit(void) +{ + serverzone = TimeZone(time(NULL)); + 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; + + /* 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; + } + + high = low + MAX_DST_WIDTH/2; + if (high < t) + high = TIME_T_MAX; + + 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 expenive 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 interpret_long_date(char *p) +{ + double d; + time_t ret; + uint32 tlow,thigh; + tlow = IVAL(p,0); + thigh = IVAL(p,4); + + if (thigh == 0) return(0); + + d = ((double)thigh)*4.0*(double)(1<<30); + d += (tlow&0xFFF00000); + d *= 1.0e-7; + + /* now adjust by 369 years to make the secs since 1970 */ + d -= TIME_FIXUP_CONSTANT; + + if (!(TIME_T_MIN <= d && d <= TIME_T_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); +} + + +/**************************************************************************** +put a 8 byte filetime from a time_t +This takes real GMT as input and converts to kludge-GMT +****************************************************************************/ +void put_long_date(char *p,time_t t) +{ + uint32 tlow,thigh; + double d; + + if (t==0) { + SIVAL(p,0,0); SIVAL(p,4,0); + return; + } + + /* this converts GMT to kludge-GMT */ + t -= TimeDiff(t) - serverzone; + + d = (double) (t); + + d += TIME_FIXUP_CONSTANT; + + d *= 1.0e7; + + thigh = (uint32)(d * (1.0/(4.0*(double)(1<<30)))); + tlow = (uint32)(d - ((double)thigh)*4.0*(double)(1<<30)); + + SIVAL(p,0,tlow); + SIVAL(p,4,thigh); +} + + +/**************************************************************************** +check if it's a null mtime +****************************************************************************/ +static 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(time_t unixdate,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(time_t unixdate,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); + + ret = make_dos_date1(unixdate,t); + ret = ((ret&0xFFFF)<<16) | make_dos_time1(unixdate,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 = IVAL(date_ptr,0); + if (!null_mtime(t)) + t += LocTimeDiff(t); + return(t); +} + +/**************************************************************************** +set the time on a file +****************************************************************************/ +BOOL set_filetime(char *fname,time_t mtime) +{ + struct utimbuf times; + + if (null_mtime(mtime)) return(True); + + times.modtime = times.actime = mtime; + + if (sys_utime(fname,×)) { + DEBUG(4,("set_filetime(%s) failed: %s\n",fname,strerror(errno))); + } + + return(True); +} + + +/**************************************************************************** + return the date and time as a string +****************************************************************************/ +char *timestring(void ) +{ + static char TimeBuf[100]; + time_t t = time(NULL); + struct tm *tm = LocalTime(&t); + +#ifdef NO_STRFTIME + strcpy(TimeBuf, asctime(tm)); +#elif defined(CLIX) || defined(CONVEX) + strftime(TimeBuf,100,"%m/%d/%y %I:%M:%S %p",tm); +#elif defined(AMPM) + strftime(TimeBuf,100,"%D %r",tm); +#elif defined(TZ_TIME) + { + int zone = TimeDiff(t); + int absZoneMinutes = (zone<0 ? -zone : zone) / 60; + size_t len = strftime(TimeBuf,sizeof(TimeBuf)-6,"%D %T",tm); + sprintf(TimeBuf+len," %c%02d%02d", + zone<0?'+':'-',absZoneMinutes/60,absZoneMinutes%60); + } +#else + strftime(TimeBuf,100,"%D %T",tm); +#endif + return(TimeBuf); +} + |