* mtime.c: high resolution time management functions
* Functions are prototyped in vlc_mtime.h.
*****************************************************************************
- * Copyright (C) 1998-2007 the VideoLAN team
+ * Copyright (C) 1998-2007 VLC authors and VideoLAN
* Copyright © 2006-2007 Rémi Denis-Courmont
* $Id$
*
* Rémi Denis-Courmont <rem$videolan,org>
* Gisle Vanem
*
- * 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
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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.
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Lesser 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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
-#include <vlc/vlc.h>
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
-#include <time.h> /* clock_gettime(), clock_nanosleep() */
+#include <vlc_common.h>
#include <assert.h>
-#include <errno.h>
-
-
-#if defined( PTH_INIT_IN_PTH_H ) /* GNU Pth */
-# include <pth.h>
-#endif
#ifdef HAVE_UNISTD_H
-# include <unistd.h> /* select() */
-#endif
-
-#ifdef HAVE_KERNEL_OS_H
-# include <kernel/OS.h>
-#endif
-
-#if defined( WIN32 ) || defined( UNDER_CE )
-# include <windows.h>
-#endif
-#if defined(HAVE_SYS_TIME_H)
-# include <sys/time.h>
+# include <unistd.h>
#endif
-
-#if !defined(HAVE_STRUCT_TIMESPEC)
-struct timespec
-{
- time_t tv_sec;
- int32_t tv_nsec;
-};
+#if !defined (_POSIX_TIMERS) || defined (_WIN32)
+# define _POSIX_TIMERS (-1)
#endif
-
-#if defined(HAVE_NANOSLEEP) && !defined(HAVE_DECL_NANOSLEEP)
-int nanosleep(struct timespec *, struct timespec *);
-#endif
-
-#if (!defined (_POSIX_CLOCK_SELECTION)) || (_POSIX_CLOCK_SELECTION < 0)
-/*
- * We cannot use the monotonic clock is clock selection is not available,
- * as it would screw vlc_cond_timedwait() completely. Instead, we have to
- * stick to the realtime clock. Nevermind it screws everything when ntpdate
- * warps the wall clock.
- */
-# undef CLOCK_MONOTONIC
-# define CLOCK_MONOTONIC CLOCK_REALTIME
-# ifndef HAVE_CLOCK_NANOSLEEP
-# error We have quite a situation here! Fix me if it ever happens.
-# endif
+#if (_POSIX_TIMERS > 0)
+# include <time.h> /* clock_gettime() */
+#else
+# include <sys/time.h>
#endif
/**
*/
char *mstrtime( char *psz_buffer, mtime_t date )
{
- static mtime_t ll1000 = 1000, ll60 = 60, ll24 = 24;
+ static const mtime_t ll1000 = 1000, ll60 = 60, ll24 = 24;
snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%02d:%02d:%02d-%03d.%03d",
(int) (date / (ll1000 * ll1000 * ll60 * ll60) % ll24),
* \param psz_buffer should be a buffer at least MSTRTIME_MAX_SIZE characters
* \return psz_buffer is returned so this can be used as printf parameter.
*/
-char *secstotimestr( char *psz_buffer, int i_seconds )
-{
- int i_hours, i_mins;
- i_mins = i_seconds / 60;
- i_hours = i_mins / 60 ;
- if( i_hours )
- {
- snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%d:%2.2d:%2.2d",
- (int) i_hours,
- (int) (i_mins % 60),
- (int) (i_seconds % 60) );
- }
- else
- {
- snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%2.2d:%2.2d",
- (int) i_mins ,
- (int) (i_seconds % 60) );
- }
- return( psz_buffer );
-}
-
-/**
- * Return a value that is no bigger than the clock precision
- * (possibly zero).
- */
-static inline unsigned mprec( void )
+char *secstotimestr( char *psz_buffer, int32_t i_seconds )
{
-#if defined (HAVE_CLOCK_NANOSLEEP)
- struct timespec ts;
- if( clock_getres( CLOCK_MONOTONIC, &ts ))
- clock_getres( CLOCK_REALTIME, &ts );
-
- return ts.tv_nsec / 1000;
-#endif
- return 0;
-}
-
-static unsigned prec = 0;
-static volatile mtime_t cached_time = 0;
-
-/**
- * Return high precision date
- *
- * Uses the gettimeofday() function when possible (1 MHz resolution) or the
- * ftime() function (1 kHz resolution).
- */
-mtime_t mdate( void )
-{
- mtime_t res;
-
-#if defined (HAVE_CLOCK_NANOSLEEP)
- struct timespec ts;
-
- /* Try to use POSIX monotonic clock if available */
- if( clock_gettime( CLOCK_MONOTONIC, &ts ) == EINVAL )
- /* Run-time fallback to real-time clock (always available) */
- (void)clock_gettime( CLOCK_REALTIME, &ts );
-
- res = ((mtime_t)ts.tv_sec * (mtime_t)1000000)
- + (mtime_t)(ts.tv_nsec / 1000);
-
-#elif defined( HAVE_KERNEL_OS_H )
- res = real_time_clock_usecs();
-
-#elif defined( WIN32 ) || defined( UNDER_CE )
- /* We don't need the real date, just the value of a high precision timer */
- static mtime_t freq = I64C(-1);
-
- if( freq == I64C(-1) )
+ if( unlikely(i_seconds < 0) )
{
- /* Extract from the Tcl source code:
- * (http://www.cs.man.ac.uk/fellowsd-bin/TIP/7.html)
- *
- * Some hardware abstraction layers use the CPU clock
- * in place of the real-time clock as a performance counter
- * reference. This results in:
- * - inconsistent results among the processors on
- * multi-processor systems.
- * - unpredictable changes in performance counter frequency
- * on "gearshift" processors such as Transmeta and
- * SpeedStep.
- * There seems to be no way to test whether the performance
- * counter is reliable, but a useful heuristic is that
- * if its frequency is 1.193182 MHz or 3.579545 MHz, it's
- * derived from a colorburst crystal and is therefore
- * the RTC rather than the TSC. If it's anything else, we
- * presume that the performance counter is unreliable.
- */
- LARGE_INTEGER buf;
-
- freq = ( QueryPerformanceFrequency( &buf ) &&
- (buf.QuadPart == I64C(1193182) || buf.QuadPart == I64C(3579545) ) )
- ? buf.QuadPart : 0;
+ secstotimestr( psz_buffer + 1, -i_seconds );
+ *psz_buffer = '-';
+ return psz_buffer;
}
- if( freq != 0 )
- {
- LARGE_INTEGER counter;
- QueryPerformanceCounter (&counter);
+ div_t d;
- /* Convert to from (1/freq) to microsecond resolution */
- /* We need to split the division to avoid 63-bits overflow */
- lldiv_t d = lldiv (counter.QuadPart, freq);
+ d = div( i_seconds, 60 );
+ i_seconds = d.rem;
+ d = div( d.quot, 60 );
- res = (d.quot * 1000000) + ((d.rem * 1000000) / freq);
- }
+ if( d.quot )
+ snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%u:%02u:%02u",
+ d.quot, d.rem, i_seconds );
else
- {
- /* Fallback on GetTickCount() which has a milisecond resolution
- * (actually, best case is about 10 ms resolution)
- * GetTickCount() only returns a DWORD thus will wrap after
- * about 49.7 days so we try to detect the wrapping. */
-
- static CRITICAL_SECTION date_lock;
- static mtime_t i_previous_time = I64C(-1);
- static int i_wrap_counts = -1;
-
- if( i_wrap_counts == -1 )
- {
- /* Initialization */
- i_previous_time = I64C(1000) * GetTickCount();
- InitializeCriticalSection( &date_lock );
- i_wrap_counts = 0;
- }
-
- EnterCriticalSection( &date_lock );
- res = I64C(1000) *
- (i_wrap_counts * I64C(0x100000000) + GetTickCount());
- if( i_previous_time > res )
- {
- /* Counter wrapped */
- i_wrap_counts++;
- res += I64C(0x100000000) * 1000;
- }
- i_previous_time = res;
- LeaveCriticalSection( &date_lock );
- }
-#else
- struct timeval tv_date;
-
- /* gettimeofday() cannot fail given &tv_date is a valid address */
- (void)gettimeofday( &tv_date, NULL );
- res = (mtime_t) tv_date.tv_sec * 1000000 + (mtime_t) tv_date.tv_usec;
-#endif
-
- return cached_time = res;
-}
-
-/**
- * Wait for a date
- *
- * This function uses select() and an system date function to wake up at a
- * precise date. It should be used for process synchronization. If current date
- * is posterior to wished date, the function returns immediately.
- * \param date The date to wake up at
- */
-void mwait( mtime_t date )
-{
- if( prec == 0 )
- prec = mprec();
-
- /* If the deadline is already elapsed, or within the clock precision,
- * do not even bother the clock. */
- if( ( date - cached_time ) < (mtime_t)prec ) // OK: mtime_t is signed
- return;
-
-#if 0 && defined (HAVE_CLOCK_NANOSLEEP)
- lldiv_t d = lldiv( date, 1000000 );
- struct timespec ts = { d.quot, d.rem * 1000 };
-
- int val;
- while( ( val = clock_nanosleep( CLOCK_MONOTONIC, TIMER_ABSTIME, &ts,
- NULL ) ) == EINTR );
- if( val == EINVAL )
- {
- ts.tv_sec = d.quot; ts.tv_nsec = d.rem * 1000;
- while( clock_nanosleep( CLOCK_REALTIME, 0, &ts, NULL ) == EINTR );
- }
-#else
-
- mtime_t delay = date - mdate();
- if( delay > 0 )
- msleep( delay );
-
-#endif
-}
-
-/**
- * More precise sleep()
- *
- * Portable usleep() function.
- * \param delay the amount of time to sleep
- */
-void msleep( mtime_t delay )
-{
- mtime_t earlier = cached_time;
-
-#if defined( HAVE_CLOCK_NANOSLEEP )
- lldiv_t d = lldiv( delay, 1000000 );
- struct timespec ts = { d.quot, d.rem * 1000 };
-
- int val;
- while( ( val = clock_nanosleep( CLOCK_MONOTONIC, 0, &ts, &ts ) ) == EINTR );
- if( val == EINVAL )
- {
- ts.tv_sec = d.quot; ts.tv_nsec = d.rem * 1000;
- while( clock_nanosleep( CLOCK_REALTIME, 0, &ts, &ts ) == EINTR );
- }
-
-#elif defined( HAVE_KERNEL_OS_H )
- snooze( delay );
-
-#elif defined( PTH_INIT_IN_PTH_H )
- pth_usleep( delay );
-
-#elif defined( ST_INIT_IN_ST_H )
- st_usleep( delay );
-
-#elif defined( WIN32 ) || defined( UNDER_CE )
- Sleep( (int) (delay / 1000) );
-
-#elif defined( HAVE_NANOSLEEP )
- struct timespec ts_delay;
-
- ts_delay.tv_sec = delay / 1000000;
- ts_delay.tv_nsec = (delay % 1000000) * 1000;
-
- while( nanosleep( &ts_delay, &ts_delay ) && ( errno == EINTR ) );
-
-#else
- struct timeval tv_delay;
-
- tv_delay.tv_sec = delay / 1000000;
- tv_delay.tv_usec = delay % 1000000;
-
- /* If a signal is caught, you are screwed. Update your OS to nanosleep()
- * or clock_nanosleep() if this is an issue. */
- select( 0, NULL, NULL, NULL, &tv_delay );
-#endif
-
- earlier += delay;
- if( cached_time < earlier )
- cached_time = earlier;
+ snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%02u:%02u",
+ d.rem, i_seconds );
+ return psz_buffer;
}
/*
void date_Change( date_t *p_date, uint32_t i_divider_n, uint32_t i_divider_d )
{
+ /* change time scale of remainder */
+ p_date->i_remainder = p_date->i_remainder * i_divider_n / p_date->i_divider_num;
p_date->i_divider_num = i_divider_n;
p_date->i_divider_den = i_divider_d;
}
*/
mtime_t date_Increment( date_t *p_date, uint32_t i_nb_samples )
{
- mtime_t i_dividend = (mtime_t)i_nb_samples * 1000000;
- p_date->date += i_dividend / p_date->i_divider_num * p_date->i_divider_den;
- p_date->i_remainder += (int)(i_dividend % p_date->i_divider_num);
+ mtime_t i_dividend = i_nb_samples * CLOCK_FREQ * p_date->i_divider_den;
+ lldiv_t d = lldiv( i_dividend, p_date->i_divider_num );
+
+ p_date->date += d.quot;
+ p_date->i_remainder += (int)d.rem;
if( p_date->i_remainder >= p_date->i_divider_num )
{
/* This is Bresenham algorithm. */
- p_date->date += p_date->i_divider_den;
+ assert( p_date->i_remainder < 2*p_date->i_divider_num);
+ p_date->date += 1;
p_date->i_remainder -= p_date->i_divider_num;
}
return p_date->date;
}
-#ifndef HAVE_GETTIMEOFDAY
-
-#ifdef WIN32
-
-/*
- * Number of micro-seconds between the beginning of the Windows epoch
- * (Jan. 1, 1601) and the Unix epoch (Jan. 1, 1970).
+/**
+ * Decrement the date and return the result, taking into account
+ * rounding errors.
*
- * This assumes all Win32 compilers have 64-bit support.
+ * \param date to decrement
+ * \param decrementation in number of samples
+ * \return date value
*/
-#if defined(_MSC_VER) || defined(_MSC_EXTENSIONS) || defined(__WATCOMC__)
-# define DELTA_EPOCH_IN_USEC 11644473600000000Ui64
-#else
-# define DELTA_EPOCH_IN_USEC 11644473600000000ULL
-#endif
-
-static uint64_t filetime_to_unix_epoch (const FILETIME *ft)
+mtime_t date_Decrement( date_t *p_date, uint32_t i_nb_samples )
{
- uint64_t res = (uint64_t) ft->dwHighDateTime << 32;
+ mtime_t i_dividend = (mtime_t)i_nb_samples * 1000000 * p_date->i_divider_den;
+ p_date->date -= i_dividend / p_date->i_divider_num;
+ unsigned i_rem_adjust = i_dividend % p_date->i_divider_num;
- res |= ft->dwLowDateTime;
- res /= 10; /* from 100 nano-sec periods to usec */
- res -= DELTA_EPOCH_IN_USEC; /* from Win epoch to Unix epoch */
- return (res);
-}
-
-static int gettimeofday (struct timeval *tv, void *tz )
-{
- FILETIME ft;
- uint64_t tim;
-
- if (!tv) {
- return VLC_EGENERIC;
+ if( p_date->i_remainder < i_rem_adjust )
+ {
+ /* This is Bresenham algorithm. */
+ assert( p_date->i_remainder > -p_date->i_divider_num);
+ p_date->date -= 1;
+ p_date->i_remainder += p_date->i_divider_num;
}
- GetSystemTimeAsFileTime (&ft);
- tim = filetime_to_unix_epoch (&ft);
- tv->tv_sec = (long) (tim / 1000000L);
- tv->tv_usec = (long) (tim % 1000000L);
- return (0);
-}
-#endif
+ p_date->i_remainder -= i_rem_adjust;
-#endif
+ return p_date->date;
+}
/**
* @return NTP 64-bits timestamp in host byte order.
*/
uint64_t NTPtime64 (void)
{
+#if (_POSIX_TIMERS > 0)
struct timespec ts;
-#if defined (CLOCK_REALTIME)
+
clock_gettime (CLOCK_REALTIME, &ts);
#else
+ struct timeval tv;
+ struct
{
- struct timeval tv;
- gettimeofday (&tv, NULL);
- ts.tv_sec = tv.tv_sec;
- ts.tv_nsec = tv.tv_usec * 1000;
- }
+ uint32_t tv_sec;
+ uint32_t tv_nsec;
+ } ts;
+
+ gettimeofday (&tv, NULL);
+ ts.tv_sec = tv.tv_sec;
+ ts.tv_nsec = tv.tv_usec * 1000;
#endif
/* Convert nanoseconds to 32-bits fraction (232 picosecond units) */
projects / vlc / blobdiff