michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /*
michael@0: ** File:		prinrval.h
michael@0: ** Description:	API to interval timing functions of NSPR.
michael@0: **
michael@0: **
michael@0: ** NSPR provides interval times that are independent of network time
michael@0: ** of day values. Interval times are (in theory) accurate regardless
michael@0: ** of host processing requirements and also very cheap to acquire. It
michael@0: ** is expected that getting an interval time while in a synchronized
michael@0: ** function (holding one's lock).
michael@0: **/
michael@0: 
michael@0: #if !defined(prinrval_h)
michael@0: #define prinrval_h
michael@0: 
michael@0: #include "prtypes.h"
michael@0: 
michael@0: PR_BEGIN_EXTERN_C
michael@0: 
michael@0: /**********************************************************************/
michael@0: /************************* TYPES AND CONSTANTS ************************/
michael@0: /**********************************************************************/
michael@0: 
michael@0: typedef PRUint32 PRIntervalTime;
michael@0: 
michael@0: /***********************************************************************
michael@0: ** DEFINES:     PR_INTERVAL_MIN
michael@0: **              PR_INTERVAL_MAX
michael@0: ** DESCRIPTION:
michael@0: **  These two constants define the range (in ticks / second) of the
michael@0: **  platform dependent type, PRIntervalTime. These constants bound both
michael@0: **  the period and the resolution of a PRIntervalTime. 
michael@0: ***********************************************************************/
michael@0: #define PR_INTERVAL_MIN 1000UL
michael@0: #define PR_INTERVAL_MAX 100000UL
michael@0: 
michael@0: /***********************************************************************
michael@0: ** DEFINES:     PR_INTERVAL_NO_WAIT
michael@0: **              PR_INTERVAL_NO_TIMEOUT
michael@0: ** DESCRIPTION:
michael@0: **  Two reserved constants are defined in the PRIntervalTime namespace.
michael@0: **  They are used to indicate that the process should wait no time (return
michael@0: **  immediately) or wait forever (never time out), respectively.
michael@0: **  Note: PR_INTERVAL_NO_TIMEOUT passed as input to PR_Connect is 
michael@0: **  interpreted as use the OS's connect timeout.
michael@0: **  
michael@0: ***********************************************************************/
michael@0: #define PR_INTERVAL_NO_WAIT 0UL
michael@0: #define PR_INTERVAL_NO_TIMEOUT 0xffffffffUL
michael@0: 
michael@0: /**********************************************************************/
michael@0: /****************************** FUNCTIONS *****************************/
michael@0: /**********************************************************************/
michael@0: 
michael@0: /***********************************************************************
michael@0: ** FUNCTION:    PR_IntervalNow
michael@0: ** DESCRIPTION:
michael@0: **  Return the value of NSPR's free running interval timer. That timer
michael@0: **  can be used to establish epochs and determine intervals (be computing
michael@0: **  the difference between two times).
michael@0: ** INPUTS:      void
michael@0: ** OUTPUTS:     void
michael@0: ** RETURN:      PRIntervalTime
michael@0: **  
michael@0: ** SIDE EFFECTS:
michael@0: **  None
michael@0: ** RESTRICTIONS:
michael@0: **  The units of PRIntervalTime are platform dependent. They are chosen
michael@0: **  such that they are appropriate for the host OS, yet provide sufficient
michael@0: **  resolution and period to be useful to clients. 
michael@0: ** MEMORY:      N/A
michael@0: ** ALGORITHM:   Platform dependent
michael@0: ***********************************************************************/
michael@0: NSPR_API(PRIntervalTime) PR_IntervalNow(void);
michael@0: 
michael@0: /***********************************************************************
michael@0: ** FUNCTION:    PR_TicksPerSecond
michael@0: ** DESCRIPTION:
michael@0: **  Return the number of ticks per second for PR_IntervalNow's clock.
michael@0: **  The value will be in the range [PR_INTERVAL_MIN..PR_INTERVAL_MAX].
michael@0: ** INPUTS:      void
michael@0: ** OUTPUTS:     void
michael@0: ** RETURN:      PRUint32
michael@0: **  
michael@0: ** SIDE EFFECTS:
michael@0: **  None
michael@0: ** RESTRICTIONS:
michael@0: **  None
michael@0: ** MEMORY:      N/A
michael@0: ** ALGORITHM:   N/A
michael@0: ***********************************************************************/
michael@0: NSPR_API(PRUint32) PR_TicksPerSecond(void);
michael@0: 
michael@0: /***********************************************************************
michael@0: ** FUNCTION:    PR_SecondsToInterval
michael@0: **              PR_MillisecondsToInterval
michael@0: **              PR_MicrosecondsToInterval
michael@0: ** DESCRIPTION:
michael@0: **  Convert standard clock units to platform dependent intervals.
michael@0: ** INPUTS:      PRUint32
michael@0: ** OUTPUTS:     void
michael@0: ** RETURN:      PRIntervalTime
michael@0: **  
michael@0: ** SIDE EFFECTS:
michael@0: **  None
michael@0: ** RESTRICTIONS:
michael@0: **  Conversion may cause overflow, which is not reported.
michael@0: ** MEMORY:      N/A
michael@0: ** ALGORITHM:   N/A
michael@0: ***********************************************************************/
michael@0: NSPR_API(PRIntervalTime) PR_SecondsToInterval(PRUint32 seconds);
michael@0: NSPR_API(PRIntervalTime) PR_MillisecondsToInterval(PRUint32 milli);
michael@0: NSPR_API(PRIntervalTime) PR_MicrosecondsToInterval(PRUint32 micro);
michael@0: 
michael@0: /***********************************************************************
michael@0: ** FUNCTION:    PR_IntervalToSeconds
michael@0: **              PR_IntervalToMilliseconds
michael@0: **              PR_IntervalToMicroseconds
michael@0: ** DESCRIPTION:
michael@0: **  Convert platform dependent intervals to standard clock units.
michael@0: ** INPUTS:      PRIntervalTime
michael@0: ** OUTPUTS:     void
michael@0: ** RETURN:      PRUint32
michael@0: **  
michael@0: ** SIDE EFFECTS:
michael@0: **  None
michael@0: ** RESTRICTIONS:
michael@0: **  Conversion may cause overflow, which is not reported.
michael@0: ** MEMORY:      N/A
michael@0: ** ALGORITHM:   N/A
michael@0: ***********************************************************************/
michael@0: NSPR_API(PRUint32) PR_IntervalToSeconds(PRIntervalTime ticks);
michael@0: NSPR_API(PRUint32) PR_IntervalToMilliseconds(PRIntervalTime ticks);
michael@0: NSPR_API(PRUint32) PR_IntervalToMicroseconds(PRIntervalTime ticks);
michael@0: 
michael@0: PR_END_EXTERN_C
michael@0: 
michael@0: 
michael@0: #endif /* !defined(prinrval_h) */
michael@0: 
michael@0: /* prinrval.h */