OSC-timetag.h

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/*
Copyright © 1998. The Regents of the University of California (Regents). 
All Rights Reserved.

Written by Matt Wright, The Center for New Music and Audio Technologies,
University of California, Berkeley.

Permission to use, copy, modify, distribute, and distribute modified versions
of this software and its documentation without fee and without a signed
licensing agreement, is hereby granted, provided that the above copyright
notice, this paragraph and the following two paragraphs appear in all copies,
modifications, and distributions.

IN NO EVENT SHALL REGENTS BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING
OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF REGENTS HAS
BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

REGENTS SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE. THE SOFTWARE AND ACCOMPANYING DOCUMENTATION, IF ANY, PROVIDED
HEREUNDER IS PROVIDED "AS IS". REGENTS HAS NO OBLIGATION TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

The OpenSound Control WWW page is 
    http://www.cnmat.berkeley.edu/OpenSoundControl
*/


/*
 OSC_timeTag.h: library for manipulating OSC time tags
 Matt Wright, 5/29/97

 Time tags in OSC have the same format as in NTP: 64 bit fixed point, with the
 top 32 bits giving number of seconds sinve midnight 1/1/1900 and the bottom
 32 bits giving fractional parts of a second.  We represent this by an 8-byte
 unsigned long if possible, or else a struct. 

 NB: On many architectures with 8-byte ints, it's illegal (like maybe a bus error)
 to dereference a pointer to an 8 byte int that's not 8-byte aligned.  
*/

#ifndef OSC_TIMETAG
#define OSC_TIMETAG

//#ifdef __sgi
    #define HAS8BYTEINT
//#endif


#ifdef HAS8BYTEINT
    typedef long long int8;
    typedef unsigned long long uint8;
    typedef unsigned long uint4;
    typedef uint8 OSCTimeTag;
#else
    typedef unsigned int uint4;
    typedef struct {
        uint4 seconds;
        uint4 fraction;
    } OSCTimeTag;
#endif



/* Return a time tag representing the current time (as of when this
   procedure is called). */
OSCTimeTag OSCTT_CurrentTime(void);

/* Return the time tag 0x0000000000000001, indicating to the receiving device
   that it should process the message immediately. */
OSCTimeTag OSCTT_Immediately(void);

/* Return the time tag 0xffffffffffffffff, a time so far in the future that
   it's effectively infinity. */
OSCTimeTag OSCTT_BiggestPossibleTimeTag(void);

/* Given a time tag and a number of seconds to add to the time tag, return
   the new time tag */
OSCTimeTag OSCTT_PlusSeconds(OSCTimeTag original, float secondsOffset);

/* Compare two time tags.  Return negative if first is < second, 0 if
   they're equal, and positive if first > second. */
int OSCTT_Compare(OSCTimeTag left, OSCTimeTag right);

#endif /*  OSC_TIMETAG */