source: vendor/3.6.23/source3/lib/time.c

/* 
   Unix SMB/CIFS implementation.
   time handling functions

   Copyright (C) Andrew Tridgell                1992-2004
   Copyright (C) Stefan (metze) Metzmacher      2002   
   Copyright (C) Jeremy Allison                 2007

   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 3 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, see <http://www.gnu.org/licenses/>.
*/

#include "includes.h"

/**
 * @file
 * @brief time handling functions
 */


#define NTTIME_INFINITY (NTTIME)0x8000000000000000LL

#if (SIZEOF_LONG == 8)
#define TIME_FIXUP_CONSTANT_INT 11644473600L
#elif (SIZEOF_LONG_LONG == 8)
#define TIME_FIXUP_CONSTANT_INT 11644473600LL
#endif


/**
  parse a nttime as a large integer in a string and return a NTTIME
*/
NTTIME nttime_from_string(const char *s)
{
        return strtoull(s, NULL, 0);
}

/**************************************************************
 Handle conversions between time_t and uint32, taking care to
 preserve the "special" values.
**************************************************************/

uint32_t convert_time_t_to_uint32_t(time_t t)
{
#if (defined(SIZEOF_TIME_T) && (SIZEOF_TIME_T == 8))
        /* time_t is 64-bit. */
        if (t == 0x8000000000000000LL) {
                return 0x80000000;
        } else if (t == 0x7FFFFFFFFFFFFFFFLL) {
                return 0x7FFFFFFF;
        }
#endif
        return (uint32_t)t;
}

time_t convert_uint32_t_to_time_t(uint32_t u)
{
#if (defined(SIZEOF_TIME_T) && (SIZEOF_TIME_T == 8))
        /* time_t is 64-bit. */
        if (u == 0x80000000) {
                return (time_t)0x8000000000000000LL;
        } else if (u == 0x7FFFFFFF) {
                return (time_t)0x7FFFFFFFFFFFFFFFLL;
        }
#endif
        return (time_t)u;
}

/****************************************************************************
 Check if NTTIME is 0.
****************************************************************************/

bool nt_time_is_zero(const NTTIME *nt)
{
        return (*nt == 0);
}

/****************************************************************************
 Convert ASN.1 GeneralizedTime string to unix-time.
 Returns 0 on failure; Currently ignores timezone. 
****************************************************************************/

time_t generalized_to_unix_time(const char *str)
{ 
        struct tm tm;

        ZERO_STRUCT(tm);

        if (sscanf(str, "%4d%2d%2d%2d%2d%2d", 
                   &tm.tm_year, &tm.tm_mon, &tm.tm_mday, 
                   &tm.tm_hour, &tm.tm_min, &tm.tm_sec) != 6) {
                return 0;
        }
        tm.tm_year -= 1900;
        tm.tm_mon -= 1;

        return timegm(&tm);
}

/*******************************************************************
 Accessor function for the server time zone offset.
 set_server_zone_offset() must have been called first.
******************************************************************/

static int server_zone_offset;

int get_server_zone_offset(void)
{
        return server_zone_offset;
}

/*******************************************************************
 Initialize the server time zone offset. Called when a client connects.
******************************************************************/

int set_server_zone_offset(time_t t)
{
        server_zone_offset = get_time_zone(t);
        return server_zone_offset;
}

/***************************************************************************
 Server versions of the above functions.
***************************************************************************/

void srv_put_dos_date(char *buf,int offset,time_t unixdate)
{
        push_dos_date((uint8_t *)buf, offset, unixdate, server_zone_offset);
}

void srv_put_dos_date2(char *buf,int offset, time_t unixdate)
{
        push_dos_date2((uint8_t *)buf, offset, unixdate, server_zone_offset);
}

void srv_put_dos_date3(char *buf,int offset,time_t unixdate)
{
        push_dos_date3((uint8_t *)buf, offset, unixdate, server_zone_offset);
}

void round_timespec(enum timestamp_set_resolution res, struct timespec *ts)
{
        switch (res) {
                case TIMESTAMP_SET_SECONDS:
                        round_timespec_to_sec(ts);
                        break;
                case TIMESTAMP_SET_MSEC:
                        round_timespec_to_usec(ts);
                        break;
                case TIMESTAMP_SET_NT_OR_BETTER:
                        /* No rounding needed. */
                        break;
        }
}

/****************************************************************************
 Take a Unix time and convert to an NTTIME structure and place in buffer 
 pointed to by p, rounded to the correct resolution.
****************************************************************************/

void put_long_date_timespec(enum timestamp_set_resolution res, char *p, struct timespec ts)
{
        NTTIME nt;
        round_timespec(res, &ts);
        unix_timespec_to_nt_time(&nt, ts);
        SIVAL(p, 0, nt & 0xFFFFFFFF);
        SIVAL(p, 4, nt >> 32);
}

void put_long_date(char *p, time_t t)
{
        struct timespec ts;
        ts.tv_sec = t;
        ts.tv_nsec = 0;
        put_long_date_timespec(TIMESTAMP_SET_SECONDS, p, ts);
}

void dos_filetime_timespec(struct timespec *tsp)
{
        tsp->tv_sec &= ~1;
        tsp->tv_nsec = 0;
}

/*******************************************************************
 Create a unix date (int GMT) from a dos date (which is actually in
 localtime).
********************************************************************/

time_t make_unix_date(const void *date_ptr, int zone_offset)
{
        uint32_t 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;
  
        ret = timegm(&t);

        ret += zone_offset;

        return(ret);
}

/*******************************************************************
 Like make_unix_date() but the words are reversed.
********************************************************************/

time_t make_unix_date2(const void *date_ptr, int zone_offset)
{
        uint32_t x,x2;

        x = IVAL(date_ptr,0);
        x2 = ((x&0xFFFF)<<16) | ((x&0xFFFF0000)>>16);
        SIVAL(&x,0,x2);

        return(make_unix_date((const void *)&x, zone_offset));
}

/*******************************************************************
 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(const void *date_ptr, int zone_offset)
{
        time_t t = (time_t)IVAL(date_ptr,0);
        if (!null_time(t)) {
                t += zone_offset;
        }
        return(t);
}

time_t srv_make_unix_date(const void *date_ptr)
{
        return make_unix_date(date_ptr, server_zone_offset);
}

time_t srv_make_unix_date2(const void *date_ptr)
{
        return make_unix_date2(date_ptr, server_zone_offset);
}

time_t srv_make_unix_date3(const void *date_ptr)
{
        return make_unix_date3(date_ptr, server_zone_offset);
}

/****************************************************************************
 Convert a normalized timeval to a timespec.
****************************************************************************/

struct timespec convert_timeval_to_timespec(const struct timeval tv)
{
        struct timespec ts;
        ts.tv_sec = tv.tv_sec;
        ts.tv_nsec = tv.tv_usec * 1000;
        return ts;
}

/****************************************************************************
 Convert a normalized timespec to a timeval.
****************************************************************************/

struct timeval convert_timespec_to_timeval(const struct timespec ts)
{
        struct timeval tv;
        tv.tv_sec = ts.tv_sec;
        tv.tv_usec = ts.tv_nsec / 1000;
        return tv;
}

/****************************************************************************
 Return a timespec for the current time
****************************************************************************/

struct timespec timespec_current(void)
{
        struct timespec ts;
        clock_gettime(CLOCK_REALTIME, &ts);
        return ts;
}

/****************************************************************************
 Return the lesser of two timespecs.
****************************************************************************/

struct timespec timespec_min(const struct timespec *ts1,
                           const struct timespec *ts2)
{
        if (ts1->tv_sec < ts2->tv_sec) return *ts1;
        if (ts1->tv_sec > ts2->tv_sec) return *ts2;
        if (ts1->tv_nsec < ts2->tv_nsec) return *ts1;
        return *ts2;
}

/****************************************************************************
  compare two timespec structures. 
  Return -1 if ts1 < ts2
  Return 0 if ts1 == ts2
  Return 1 if ts1 > ts2
****************************************************************************/

int timespec_compare(const struct timespec *ts1, const struct timespec *ts2)
{
        if (ts1->tv_sec  > ts2->tv_sec)  return 1;
        if (ts1->tv_sec  < ts2->tv_sec)  return -1;
        if (ts1->tv_nsec > ts2->tv_nsec) return 1;
        if (ts1->tv_nsec < ts2->tv_nsec) return -1;
        return 0;
}

/****************************************************************************
 Round up a timespec if nsec > 500000000, round down if lower,
 then zero nsec.
****************************************************************************/

void round_timespec_to_sec(struct timespec *ts)
{
        ts->tv_sec = convert_timespec_to_time_t(*ts);
        ts->tv_nsec = 0;
}

/****************************************************************************
 Round a timespec to usec value.
****************************************************************************/

void round_timespec_to_usec(struct timespec *ts)
{
        struct timeval tv = convert_timespec_to_timeval(*ts);
        *ts = convert_timeval_to_timespec(tv);
        while (ts->tv_nsec > 1000000000) {
                ts->tv_sec += 1;
                ts->tv_nsec -= 1000000000;
        }
}

/****************************************************************************
 Interprets an nt time into a unix struct timespec.
 Differs from nt_time_to_unix in that an 8 byte value of 0xffffffffffffffff
 will be returned as (time_t)-1, whereas nt_time_to_unix returns 0 in this case.
****************************************************************************/

struct timespec interpret_long_date(const char *p)
{
        NTTIME nt;
        nt = IVAL(p,0) + ((uint64_t)IVAL(p,4) << 32);
        if (nt == (uint64_t)-1) {
                struct timespec ret;
                ret.tv_sec = (time_t)-1;
                ret.tv_nsec = 0;
                return ret;
        }
        return nt_time_to_unix_timespec(&nt);
}

/*******************************************************************
 Re-read the smb serverzone value.
******************************************************************/

static struct timeval start_time_hires;

void TimeInit(void)
{
        set_server_zone_offset(time(NULL));

        DEBUG(4,("TimeInit: Serverzone is %d\n", server_zone_offset));

        /* Save the start time of this process. */
        if (start_time_hires.tv_sec == 0 && start_time_hires.tv_usec == 0) {
                GetTimeOfDay(&start_time_hires);
        }
}

/**********************************************************************
 Return a timeval struct of the uptime of this process. As TimeInit is
 done before a daemon fork then this is the start time from the parent
 daemon start. JRA.
***********************************************************************/

void get_process_uptime(struct timeval *ret_time)
{
        struct timeval time_now_hires;

        GetTimeOfDay(&time_now_hires);
        ret_time->tv_sec = time_now_hires.tv_sec - start_time_hires.tv_sec;
        if (time_now_hires.tv_usec < start_time_hires.tv_usec) {
                ret_time->tv_sec -= 1;
                ret_time->tv_usec = 1000000 + (time_now_hires.tv_usec - start_time_hires.tv_usec);
        } else {
                ret_time->tv_usec = time_now_hires.tv_usec - start_time_hires.tv_usec;
        }
}

/**
 * @brief Get the startup time of the server.
 *
 * @param[out] ret_time A pointer to a timveal structure to set the startup
 *                      time.
 */
void get_startup_time(struct timeval *ret_time)
{
        ret_time->tv_sec = start_time_hires.tv_sec;
        ret_time->tv_usec = start_time_hires.tv_usec;
}


/****************************************************************************
 Convert a NTTIME structure to a time_t.
 It's originally in "100ns units".

 This is an absolute version of the one above.
 By absolute I mean, it doesn't adjust from 1/1/1601 to 1/1/1970
 if the NTTIME was 5 seconds, the time_t is 5 seconds. JFM
****************************************************************************/

time_t nt_time_to_unix_abs(const NTTIME *nt)
{
        uint64_t d;

        if (*nt == 0) {
                return (time_t)0;
        }

        if (*nt == (uint64_t)-1) {
                return (time_t)-1;
        }

        if (*nt == NTTIME_INFINITY) {
                return (time_t)-1;
        }

        /* reverse the time */
        /* it's a negative value, turn it to positive */
        d=~*nt;

        d += 1000*1000*10/2;
        d /= 1000*1000*10;

        if (!(TIME_T_MIN <= ((time_t)d) && ((time_t)d) <= TIME_T_MAX)) {
                return (time_t)0;
        }

        return (time_t)d;
}

time_t uint64s_nt_time_to_unix_abs(const uint64_t *src)
{
        NTTIME nttime;
        nttime = *src;
        return nt_time_to_unix_abs(&nttime);
}

/****************************************************************************
 Put a 8 byte filetime from a struct timespec. Uses GMT.
****************************************************************************/

void unix_timespec_to_nt_time(NTTIME *nt, struct timespec ts)
{
        uint64_t d;

        if (ts.tv_sec ==0 && ts.tv_nsec == 0) {
                *nt = 0;
                return;
        }
        if (ts.tv_sec == TIME_T_MAX) {
                *nt = 0x7fffffffffffffffLL;
                return;
        }               
        if (ts.tv_sec == (time_t)-1) {
                *nt = (uint64_t)-1;
                return;
        }               

        d = ts.tv_sec;
        d += TIME_FIXUP_CONSTANT_INT;
        d *= 1000*1000*10;
        /* d is now in 100ns units. */
        d += (ts.tv_nsec / 100);

        *nt = d;
}

#if 0
void nt_time_to_unix_timespec(struct timespec *ts, NTTIME t)
{
        if (ts == NULL) {
                return;
        }

        /* t starts in 100 nsec units since 1601-01-01. */

        t *= 100;
        /* t is now in nsec units since 1601-01-01. */

        t -= TIME_FIXUP_CONSTANT*1000*1000*100;
        /* t is now in nsec units since the UNIX epoch 1970-01-01. */

        ts->tv_sec  = t / 1000000000LL;

        if (TIME_T_MIN > ts->tv_sec || ts->tv_sec > TIME_T_MAX) {
                ts->tv_sec  = 0;
                ts->tv_nsec = 0;
                return;
        }

        ts->tv_nsec = t - ts->tv_sec*1000000000LL;
}
#endif

/****************************************************************************
 Convert a time_t to a NTTIME structure

 This is an absolute version of the one above.
 By absolute I mean, it doesn't adjust from 1/1/1970 to 1/1/1601
 If the time_t was 5 seconds, the NTTIME is 5 seconds. JFM
****************************************************************************/

void unix_to_nt_time_abs(NTTIME *nt, time_t t)
{
        double d;

        if (t==0) {
                *nt = 0;
                return;
        }

        if (t == TIME_T_MAX) {
                *nt = 0x7fffffffffffffffLL;
                return;
        }
                
        if (t == (time_t)-1) {
                /* that's what NT uses for infinite */
                *nt = NTTIME_INFINITY;
                return;
        }               

        d = (double)(t);
        d *= 1.0e7;

        *nt = (NTTIME)d;

        /* convert to a negative value */
        *nt=~*nt;
}


/****************************************************************************
 Utility function that always returns a const string even if localtime
 and asctime fail.
****************************************************************************/

const char *time_to_asc(const time_t t)
{
        const char *asct;
        struct tm *lt = localtime(&t);

        if (!lt) {
                return "unknown time";
        }

        asct = asctime(lt);
        if (!asct) {
                return "unknown time";
        }
        return asct;
}

const char *display_time(NTTIME nttime)
{
        float high;
        float low;
        int sec;
        int days, hours, mins, secs;

        if (nttime==0)
                return "Now";

        if (nttime==NTTIME_INFINITY)
                return "Never";

        high = 65536;   
        high = high/10000;
        high = high*65536;
        high = high/1000;
        high = high * (~(nttime >> 32));

        low = ~(nttime & 0xFFFFFFFF);
        low = low/(1000*1000*10);

        sec=(int)(high+low);

        days=sec/(60*60*24);
        hours=(sec - (days*60*60*24)) / (60*60);
        mins=(sec - (days*60*60*24) - (hours*60*60) ) / 60;
        secs=sec - (days*60*60*24) - (hours*60*60) - (mins*60);

        return talloc_asprintf(talloc_tos(), "%u days, %u hours, %u minutes, "
                               "%u seconds", days, hours, mins, secs);
}

bool nt_time_is_set(const NTTIME *nt)
{
        if (*nt == 0x7FFFFFFFFFFFFFFFLL) {
                return false;
        }

        if (*nt == NTTIME_INFINITY) {
                return false;
        }

        return true;
}