X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=src%2Fmisc%2Fmtime.c;h=115dbe9ffc6cce42a2ef2e9a5dde211a035b9fd1;hb=599fbde71fba4397aa62fe81f957ee641654997c;hp=324feea0705357fca0840a1b4d3ce7779881ac95;hpb=a04423daf678b33f451c5d24d7129d95957e4318;p=vlc diff --git a/src/misc/mtime.c b/src/misc/mtime.c index 324feea070..115dbe9ffc 100644 --- a/src/misc/mtime.c +++ b/src/misc/mtime.c @@ -1,17 +1,20 @@ /***************************************************************************** * mtime.c: high resolution time management functions - * Functions are prototyped in mtime.h. + * Functions are prototyped in vlc_mtime.h. ***************************************************************************** - * Copyright (C) 1998-2001, 2003 VideoLAN - * $Id: mtime.c,v 1.39 2003/12/03 21:50:50 sigmunau Exp $ + * Copyright (C) 1998-2007 the VideoLAN team + * Copyright © 2006-2007 Rémi Denis-Courmont + * $Id$ * * Authors: Vincent Seguin + * Rémi Denis-Courmont + * 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 * (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 @@ -19,25 +22,23 @@ * * 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., 59 Temple Place - Suite 330, Boston, MA 02111, USA. + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA. *****************************************************************************/ -/* - * TODO: - * see if using Linux real-time extensions is possible and profitable - */ - /***************************************************************************** * Preamble *****************************************************************************/ -#include /* sprintf() */ - -#include -#if defined( PTH_INIT_IN_PTH_H ) /* GNU Pth */ -# include +#ifdef HAVE_CONFIG_H +# include "config.h" #endif +#include + +#include /* clock_gettime(), clock_nanosleep() */ +#include +#include + #ifdef HAVE_UNISTD_H # include /* select() */ #endif @@ -48,11 +49,20 @@ #if defined( WIN32 ) || defined( UNDER_CE ) # include -#else +# include +#endif + +#if defined(HAVE_SYS_TIME_H) # include #endif -#if defined(HAVE_NANOSLEEP) && !defined(HAVE_STRUCT_TIMESPEC) +#if defined(__APPLE__) && !defined(__powerpc__) && !defined(__ppc__) && !defined(__ppc64__) +#define USE_APPLE_MACH 1 +# include +# include +#endif + +#if !defined(HAVE_STRUCT_TIMESPEC) struct timespec { time_t tv_sec; @@ -64,19 +74,37 @@ struct timespec int nanosleep(struct timespec *, struct timespec *); #endif +#if !defined (_POSIX_CLOCK_SELECTION) +# define _POSIX_CLOCK_SELECTION (-1) +#endif + +# if (_POSIX_CLOCK_SELECTION < 0) +/* + * We cannot use the monotonic clock if 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 up when ntpdate + * warps the wall clock. + */ +# undef CLOCK_MONOTONIC +# define CLOCK_MONOTONIC CLOCK_REALTIME +#elif !defined (HAVE_CLOCK_NANOSLEEP) +/* Clock selection without clock in the first place, I don't think so. */ +# error We have quite a situation here! Fix me if it ever happens. +#endif + /** * Return a date in a readable format * * This function converts a mtime date into a string. * psz_buffer should be a buffer long enough to store the formatted - * date. + * date. * \param date to be converted * \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 *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), @@ -97,79 +125,133 @@ char *mstrtime( char *psz_buffer, mtime_t date ) * \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 ) +char *secstotimestr( char *psz_buffer, int32_t i_seconds ) { - snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%d:%2.2d:%2.2d", - (int) (i_seconds / (60 *60)), - (int) ((i_seconds / 60) % 60), - (int) (i_seconds % 60) ); - return( psz_buffer ); + if( unlikely(i_seconds < 0) ) + { + secstotimestr( psz_buffer + 1, -i_seconds ); + *psz_buffer = '-'; + return psz_buffer; + } + + div_t d; + + d = div( i_seconds, 60 ); + i_seconds = d.rem; + d = div( d.quot, 60 ); + + if( d.quot ) + snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%u:%02u:%02u", + d.quot, d.rem, i_seconds ); + else + snprintf( psz_buffer, MSTRTIME_MAX_SIZE, "%02u:%02u", + d.rem, i_seconds ); + return psz_buffer; } +#if defined (HAVE_CLOCK_NANOSLEEP) +static unsigned prec = 0; + +static void mprec_once( void ) +{ + struct timespec ts; + if( clock_getres( CLOCK_MONOTONIC, &ts )) + clock_getres( CLOCK_REALTIME, &ts ); + + prec = ts.tv_nsec / 1000; +} +#endif + +/** + * Return a value that is no bigger than the clock precision + * (possibly zero). + */ +static inline unsigned mprec( void ) +{ +#if defined (HAVE_CLOCK_NANOSLEEP) + static pthread_once_t once = PTHREAD_ONCE_INIT; + pthread_once( &once, mprec_once ); + return prec; +#else + return 0; +#endif +} + +#ifdef USE_APPLE_MACH +static mach_timebase_info_data_t mtime_timebase_info; +static pthread_once_t mtime_timebase_info_once = PTHREAD_ONCE_INIT; +static void mtime_init_timebase(void) +{ + mach_timebase_info(&mtime_timebase_info); +} +#endif + /** * Return high precision date * - * Uses the gettimeofday() function when possible (1 MHz resolution) or the - * ftime() function (1 kHz resolution). + * Use a 1 MHz clock when possible, or 1 kHz + * + * Beware ! It doesn't reflect the actual date (since epoch), but can be the machine's uptime or anything (when monotonic clock is used) */ mtime_t mdate( void ) { -#if defined( HAVE_KERNEL_OS_H ) - return( real_time_clock_usecs() ); + 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( USE_APPLE_MACH ) + pthread_once(&mtime_timebase_info_once, mtime_init_timebase); + uint64_t date = mach_absolute_time(); + mach_timebase_info_data_t tb = mtime_timebase_info; + + /* tb.denom is uint32_t, switch to 64 bits to prevent overflow. */ + uint64_t denom = tb.denom; + + /* Switch to microsecs */ + denom *= 1000LL; + + /* Split the division to prevent overflow */ + lldiv_t d = lldiv (tb.numer, denom); + + res = (d.quot * date) + ((d.rem * date) / denom); #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); - mtime_t usec_time; + LARGE_INTEGER counter, freq; + if (!QueryPerformanceCounter (&counter) + || !QueryPerformanceFrequency (&freq)) + abort(); - if( freq == I64C(-1) ) - { - /* 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. - */ - - freq = ( QueryPerformanceFrequency( (LARGE_INTEGER *)&freq ) && - (freq == I64C(1193182) || freq == I64C(3579545) ) ) - ? freq : 0; - } + /* 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.QuadPart); - if( freq != 0 ) - { - /* Microsecond resolution */ - QueryPerformanceCounter( (LARGE_INTEGER *)&usec_time ); - return ( usec_time * 1000000 ) / freq; - } - - /* Milisecond resolution (actually, best case is about 10 ms resolution) */ - return 1000 * GetTickCount(); + res = (d.quot * 1000000) + ((d.rem * 1000000) / freq.QuadPart); #else struct timeval tv_date; - /* gettimeofday() could return an error, and should be tested. However, the - * only possible error, according to 'man', is EFAULT, which can not happen - * here, since tv is a local variable. */ - gettimeofday( &tv_date, NULL ); - return( (mtime_t) tv_date.tv_sec * 1000000 + (mtime_t) tv_date.tv_usec ); - + /* 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 res; } +#undef mwait /** * Wait for a date * @@ -180,116 +262,292 @@ mtime_t mdate( void ) */ void mwait( mtime_t date ) { -#if defined( HAVE_KERNEL_OS_H ) - mtime_t delay; - - delay = date - real_time_clock_usecs(); - if( delay <= 0 ) + /* If the deadline is already elapsed, or within the clock precision, + * do not even bother the system timer. */ + date -= mprec(); + +#if 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 ) { - return; + ts.tv_sec = d.quot; ts.tv_nsec = d.rem * 1000; + while( clock_nanosleep( CLOCK_REALTIME, 0, &ts, NULL ) == EINTR ); } - snooze( delay ); -#elif defined( WIN32 ) || defined( UNDER_CE ) - mtime_t usec_time, delay; +#elif defined (WIN32) + mtime_t i_total; - usec_time = mdate(); - delay = date - usec_time; - if( delay <= 0 ) + while( (i_total = (date - mdate())) > 0 ) { - return; + const mtime_t i_sleep = i_total / 1000; + DWORD i_delay = (i_sleep > 0x7fffffff) ? 0x7fffffff : i_sleep; + vlc_testcancel(); + SleepEx( i_delay, TRUE ); } - msleep( delay ); + vlc_testcancel(); #else + mtime_t delay = date - mdate(); + if( delay > 0 ) + msleep( delay ); - struct timeval tv_date; - mtime_t delay; /* delay in msec, signed to detect errors */ +#endif +} - /* see mdate() about gettimeofday() possible errors */ - gettimeofday( &tv_date, NULL ); - /* calculate delay and check if current date is before wished date */ - delay = date - (mtime_t) tv_date.tv_sec * 1000000 - - (mtime_t) tv_date.tv_usec - - 10000; +#include "libvlc.h" /* vlc_backtrace() */ +#undef msleep - /* Linux/i386 has a granularity of 10 ms. It's better to be in advance - * than to be late. */ - if( delay <= 0 ) /* wished date is now or already passed */ +/** + * Portable usleep(). Cancellation point. + * + * \param delay the amount of time to sleep + */ +void msleep( mtime_t delay ) +{ +#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 ) { - return; + ts.tv_sec = d.quot; ts.tv_nsec = d.rem * 1000; + while( clock_nanosleep( CLOCK_REALTIME, 0, &ts, &ts ) == EINTR ); } -# if defined( PTH_INIT_IN_PTH_H ) - pth_usleep( delay ); +#elif defined( HAVE_KERNEL_OS_H ) + snooze( delay ); -# elif defined( ST_INIT_IN_ST_H ) - st_usleep( delay ); +#elif defined( WIN32 ) || defined( UNDER_CE ) + mwait (mdate () + delay); -# else +#elif defined( HAVE_NANOSLEEP ) + struct timespec ts_delay; -# if defined( HAVE_NANOSLEEP ) - { - struct timespec ts_delay; - ts_delay.tv_sec = delay / 1000000; - ts_delay.tv_nsec = (delay % 1000000) * 1000; + ts_delay.tv_sec = delay / 1000000; + ts_delay.tv_nsec = (delay % 1000000) * 1000; - nanosleep( &ts_delay, NULL ); - } + while( nanosleep( &ts_delay, &ts_delay ) && ( errno == EINTR ) ); -# else - tv_date.tv_sec = delay / 1000000; - tv_date.tv_usec = delay % 1000000; - /* see msleep() about select() errors */ - select( 0, NULL, NULL, NULL, &tv_date ); -# endif +#elif defined (USE_APPLE_MACH) + /* The version that should be used, if it was cancelable */ + pthread_once(&mtime_timebase_info_once, mtime_init_timebase); + uint64_t mach_time = delay * 1000 * mtime_timebase_info.denom / mtime_timebase_info.numer; + mach_wait_until(mach_time + mach_absolute_time()); -# endif +#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 } +/* + * Date management (internal and external) + */ + /** - * More precise sleep() + * Initialize a date_t. * - * Portable usleep() function. - * \param delay the amount of time to sleep + * \param date to initialize + * \param divider (sample rate) numerator + * \param divider (sample rate) denominator */ -void msleep( mtime_t delay ) + +void date_Init( date_t *p_date, uint32_t i_divider_n, uint32_t i_divider_d ) { -#if defined( HAVE_KERNEL_OS_H ) - snooze( delay ); + p_date->date = 0; + p_date->i_divider_num = i_divider_n; + p_date->i_divider_den = i_divider_d; + p_date->i_remainder = 0; +} -#elif defined( PTH_INIT_IN_PTH_H ) - pth_usleep( delay ); +/** + * Change a date_t. + * + * \param date to change + * \param divider (sample rate) numerator + * \param divider (sample rate) denominator + */ -#elif defined( ST_INIT_IN_ST_H ) - st_usleep( delay ); +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; +} -#elif defined( WIN32 ) || defined( UNDER_CE ) - Sleep( (int) (delay / 1000) ); +/** + * Set the date value of a date_t. + * + * \param date to set + * \param date value + */ +void date_Set( date_t *p_date, mtime_t i_new_date ) +{ + p_date->date = i_new_date; + p_date->i_remainder = 0; +} -#elif defined( HAVE_NANOSLEEP ) - struct timespec ts_delay; +/** + * Get the date of a date_t + * + * \param date to get + * \return date value + */ +mtime_t date_Get( const date_t *p_date ) +{ + return p_date->date; +} - ts_delay.tv_sec = delay / 1000000; - ts_delay.tv_nsec = (delay % 1000000) * 1000; +/** + * Move forwards or backwards the date of a date_t. + * + * \param date to move + * \param difference value + */ +void date_Move( date_t *p_date, mtime_t i_difference ) +{ + p_date->date += i_difference; +} + +/** + * Increment the date and return the result, taking into account + * rounding errors. + * + * \param date to increment + * \param incrementation in number of samples + * \return date value + */ +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->i_divider_den; + p_date->date += i_dividend / p_date->i_divider_num; + p_date->i_remainder += (int)(i_dividend % p_date->i_divider_num); + + if( p_date->i_remainder >= p_date->i_divider_num ) + { + /* This is Bresenham algorithm. */ + assert( p_date->i_remainder < 2*p_date->i_divider_num); + p_date->date += 1; + p_date->i_remainder -= p_date->i_divider_num; + } - nanosleep( &ts_delay, NULL ); + return p_date->date; +} + +/** + * Decrement the date and return the result, taking into account + * rounding errors. + * + * \param date to decrement + * \param decrementation in number of samples + * \return date value + */ +mtime_t date_Decrement( date_t *p_date, uint32_t i_nb_samples ) +{ + 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; + 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; + } + + p_date->i_remainder -= i_rem_adjust; + + 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). + * + * This assumes all Win32 compilers have 64-bit support. + */ +#if defined(_MSC_VER) || defined(_MSC_EXTENSIONS) || defined(__WATCOMC__) +# define DELTA_EPOCH_IN_USEC 11644473600000000Ui64 #else - struct timeval tv_delay; +# define DELTA_EPOCH_IN_USEC 11644473600000000ULL +#endif - tv_delay.tv_sec = delay / 1000000; - tv_delay.tv_usec = delay % 1000000; +static uint64_t filetime_to_unix_epoch (const FILETIME *ft) +{ + uint64_t res = (uint64_t) ft->dwHighDateTime << 32; - /* select() return value should be tested, since several possible errors - * can occur. However, they should only happen in very particular occasions - * (i.e. when a signal is sent to the thread, or when memory is full), and - * can be ignored. */ - select( 0, NULL, NULL, NULL, &tv_delay ); + 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; + } + GetSystemTimeAsFileTime (&ft); + tim = filetime_to_unix_epoch (&ft); + tv->tv_sec = (long) (tim / 1000000L); + tv->tv_usec = (long) (tim % 1000000L); + return (0); +} #endif + +#endif + +/** + * @return NTP 64-bits timestamp in host byte order. + */ +uint64_t NTPtime64 (void) +{ + struct timespec ts; +#if defined (CLOCK_REALTIME) + clock_gettime (CLOCK_REALTIME, &ts); +#else + { + struct timeval tv; + 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) */ + uint64_t t = (uint64_t)(ts.tv_nsec) << 32; + t /= 1000000000; + + + /* There is 70 years (incl. 17 leap ones) offset to the Unix Epoch. + * No leap seconds during that period since they were not invented yet. + */ + assert (t < 0x100000000); + t |= ((70LL * 365 + 17) * 24 * 60 * 60 + ts.tv_sec) << 32; + return t; }