vlc_mtime.h 4.13 KB
Newer Older
1
/*****************************************************************************
2
 * mtime.h: high resolution time management functions
Michel Kaempf's avatar
Michel Kaempf committed
3 4 5 6 7 8 9
 * 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.
10
 *****************************************************************************
11
 * Copyright (C) 1996, 1997, 1998, 1999, 2000 the VideoLAN team
12
 * $Id$
13
 *
14
 * Authors: Vincent Seguin <seguin@via.ecp.fr>
15 16 17 18 19
 *
 * 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.
20
 *
21 22
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
23 24
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
25
 *
26 27
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
Antoine Cellerier's avatar
Antoine Cellerier committed
28
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
29 30
 *****************************************************************************/

31
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
32
 * LAST_MDATE: date which will never happen
33
 *****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
34 35 36 37
 * 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.
38
 *****************************************************************************/
39
#define LAST_MDATE ((mtime_t)((uint64_t)(-1)/2))
Michel Kaempf's avatar
Michel Kaempf committed
40

41
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
42
 * MSTRTIME_MAX_SIZE: maximum possible size of mstrtime
43
 *****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
44
 * This values is the maximal possible size of the string returned by the
Michel Kaempf's avatar
Michel Kaempf committed
45 46
 * mstrtime() function, including '-' and the final '\0'. It should be used to
 * allocate the buffer.
47
 *****************************************************************************/
Michel Kaempf's avatar
Michel Kaempf committed
48
#define MSTRTIME_MAX_SIZE 22
Michel Kaempf's avatar
Michel Kaempf committed
49

50 51 52 53 54
/* Well, Duh? But it does clue us in that we are converting from
   millisecond quantity to a second quantity or vice versa.
*/
#define MILLISECONDS_PER_SEC 1000

55
#define msecstotimestr(psz_buffer, msecs) \
56
  secstotimestr( psz_buffer, (msecs / (int) MILLISECONDS_PER_SEC) )
57

58
/*****************************************************************************
Michel Kaempf's avatar
Michel Kaempf committed
59
 * Prototypes
60
 *****************************************************************************/
61 62 63 64
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 ) );
65
VLC_EXPORT( char *,  secstotimestr, ( char *psz_buffer, int secs ) );
Sam Hocevar's avatar
 
Sam Hocevar committed
66

67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83
/*****************************************************************************
 * 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 ) );