mirror of https://code.videolan.org/videolan/vlc
140 lines
5.6 KiB
C
140 lines
5.6 KiB
C
/*****************************************************************************
|
|
* vlc_mtime.h: high resolution time management functions
|
|
*****************************************************************************
|
|
* This header provides portable high precision time management functions,
|
|
* which should be the only ones used in other segments of the program, since
|
|
* functions like gettimeofday() and ftime() are not always supported.
|
|
* Most functions are declared as inline or as macros since they are only
|
|
* interfaces to system calls and have to be called frequently.
|
|
* 'm' stands for 'micro', since maximum resolution is the microsecond.
|
|
* Functions prototyped are implemented in interface/mtime.c.
|
|
*****************************************************************************
|
|
* Copyright (C) 1996, 1997, 1998, 1999, 2000 the VideoLAN team
|
|
* $Id$
|
|
*
|
|
* Authors: Vincent Seguin <seguin@via.ecp.fr>
|
|
*
|
|
* 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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
|
|
*****************************************************************************/
|
|
|
|
#ifndef __VLC_MTIME_H
|
|
# define __VLC_MTIME_H 1
|
|
|
|
/*****************************************************************************
|
|
* LAST_MDATE: date which will never happen
|
|
*****************************************************************************
|
|
* This date can be used as a 'never' date, to mark missing events in a function
|
|
* supposed to return a date, such as nothing to display in a function
|
|
* returning the date of the first image to be displayed. It can be used in
|
|
* comparaison with other values: all existing dates will be earlier.
|
|
*****************************************************************************/
|
|
#define LAST_MDATE ((mtime_t)((uint64_t)(-1)/2))
|
|
|
|
/*****************************************************************************
|
|
* MSTRTIME_MAX_SIZE: maximum possible size of mstrtime
|
|
*****************************************************************************
|
|
* This values is the maximal possible size of the string returned by the
|
|
* mstrtime() function, including '-' and the final '\0'. It should be used to
|
|
* allocate the buffer.
|
|
*****************************************************************************/
|
|
#define MSTRTIME_MAX_SIZE 22
|
|
|
|
/*****************************************************************************
|
|
* Prototypes
|
|
*****************************************************************************/
|
|
VLC_EXPORT( char *, mstrtime, ( char *psz_buffer, mtime_t date ) );
|
|
VLC_EXPORT( mtime_t, mdate, ( void ) );
|
|
VLC_EXPORT( void, mwait, ( mtime_t date ) );
|
|
VLC_EXPORT( void, msleep, ( mtime_t delay ) );
|
|
VLC_EXPORT( char *, secstotimestr, ( char *psz_buffer, int32_t secs ) );
|
|
|
|
# define VLC_HARD_MIN_SLEEP 10000 /* 10 milliseconds = 1 tick at 100Hz */
|
|
|
|
#if defined (__GNUC__) \
|
|
&& ((__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3))
|
|
/* Linux has 100, 250, 300 or 1000Hz
|
|
*
|
|
* HZ=100 by default on FreeBSD, but some architectures use a 1000Hz timer
|
|
*/
|
|
# define VLC_SOFT_MIN_SLEEP 9000000 /* 9 seconds */
|
|
|
|
static
|
|
__attribute__((unused))
|
|
__attribute__((noinline))
|
|
__attribute__((error("sorry, cannot sleep for such short a time")))
|
|
mtime_t impossible_delay( mtime_t delay )
|
|
{
|
|
(void) delay;
|
|
return VLC_HARD_MIN_SLEEP;
|
|
}
|
|
|
|
static
|
|
__attribute__((unused))
|
|
__attribute__((noinline))
|
|
__attribute__((warning("use proper event handling instead of short delay")))
|
|
mtime_t harmful_delay( mtime_t delay )
|
|
{
|
|
return delay;
|
|
}
|
|
|
|
# define check_delay( d ) \
|
|
((__builtin_constant_p(d < VLC_HARD_MIN_SLEEP) \
|
|
&& (d < VLC_HARD_MIN_SLEEP)) \
|
|
? impossible_delay(d) \
|
|
: ((__builtin_constant_p(d < VLC_SOFT_MIN_SLEEP) \
|
|
&& (d < VLC_SOFT_MIN_SLEEP)) \
|
|
? harmful_delay(d) \
|
|
: d))
|
|
|
|
static
|
|
__attribute__((unused))
|
|
__attribute__((noinline))
|
|
__attribute__((error("deadlines can not be constant")))
|
|
mtime_t impossible_deadline( mtime_t deadline )
|
|
{
|
|
return deadline;
|
|
}
|
|
|
|
# define check_deadline( d ) \
|
|
(__builtin_constant_p(d) ? impossible_deadline(d) : d)
|
|
#else
|
|
# define check_delay(d) (d)
|
|
# define check_deadline(d) (d)
|
|
#endif
|
|
|
|
#define msleep(d) msleep(check_delay(d))
|
|
#define mwait(d) mwait(check_deadline(d))
|
|
|
|
/*****************************************************************************
|
|
* date_t: date incrementation without long-term rounding errors
|
|
*****************************************************************************/
|
|
struct date_t
|
|
{
|
|
mtime_t date;
|
|
uint32_t i_divider_num;
|
|
uint32_t i_divider_den;
|
|
uint32_t i_remainder;
|
|
};
|
|
|
|
VLC_EXPORT( void, date_Init, ( date_t *, uint32_t, uint32_t ) );
|
|
VLC_EXPORT( void, date_Change, ( date_t *, uint32_t, uint32_t ) );
|
|
VLC_EXPORT( void, date_Set, ( date_t *, mtime_t ) );
|
|
VLC_EXPORT( mtime_t, date_Get, ( const date_t * ) );
|
|
VLC_EXPORT( void, date_Move, ( date_t *, mtime_t ) );
|
|
VLC_EXPORT( mtime_t, date_Increment, ( date_t *, uint32_t ) );
|
|
VLC_EXPORT( mtime_t, date_Decrement, ( date_t *, uint32_t ) );
|
|
VLC_EXPORT( uint64_t, NTPtime64, ( void ) );
|
|
#endif /* !__VLC_MTIME_ */
|