prinrval.h
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- /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
- /* ***** BEGIN LICENSE BLOCK *****
- * Version: MPL 1.1/GPL 2.0/LGPL 2.1
- *
- * The contents of this file are subject to the Mozilla Public License Version
- * 1.1 (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- * http://www.mozilla.org/MPL/
- *
- * Software distributed under the License is distributed on an "AS IS" basis,
- * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
- * for the specific language governing rights and limitations under the
- * License.
- *
- * The Original Code is the Netscape Portable Runtime (NSPR).
- *
- * The Initial Developer of the Original Code is
- * Netscape Communications Corporation.
- * Portions created by the Initial Developer are Copyright (C) 1998-2000
- * the Initial Developer. All Rights Reserved.
- *
- * Contributor(s):
- *
- * Alternatively, the contents of this file may be used under the terms of
- * either the GNU General Public License Version 2 or later (the "GPL"), or
- * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
- * in which case the provisions of the GPL or the LGPL are applicable instead
- * of those above. If you wish to allow use of your version of this file only
- * under the terms of either the GPL or the LGPL, and not to allow others to
- * use your version of this file under the terms of the MPL, indicate your
- * decision by deleting the provisions above and replace them with the notice
- * and other provisions required by the GPL or the LGPL. If you do not delete
- * the provisions above, a recipient may use your version of this file under
- * the terms of any one of the MPL, the GPL or the LGPL.
- *
- * ***** END LICENSE BLOCK ***** */
- /*
- ** File: prinrval.h
- ** Description: API to interval timing functions of NSPR.
- **
- **
- ** NSPR provides interval times that are independent of network time
- ** of day values. Interval times are (in theory) accurate regardless
- ** of host processing requirements and also very cheap to acquire. It
- ** is expected that getting an interval time while in a synchronized
- ** function (holding one's lock).
- **/
- #if !defined(prinrval_h)
- #define prinrval_h
- #include "prtypes.h"
- PR_BEGIN_EXTERN_C
- /**********************************************************************/
- /************************* TYPES AND CONSTANTS ************************/
- /**********************************************************************/
- typedef PRUint32 PRIntervalTime;
- /***********************************************************************
- ** DEFINES: PR_INTERVAL_MIN
- ** PR_INTERVAL_MAX
- ** DESCRIPTION:
- ** These two constants define the range (in ticks / second) of the
- ** platform dependent type, PRIntervalTime. These constants bound both
- ** the period and the resolution of a PRIntervalTime.
- ***********************************************************************/
- #define PR_INTERVAL_MIN 1000UL
- #define PR_INTERVAL_MAX 100000UL
- /***********************************************************************
- ** DEFINES: PR_INTERVAL_NO_WAIT
- ** PR_INTERVAL_NO_TIMEOUT
- ** DESCRIPTION:
- ** Two reserved constants are defined in the PRIntervalTime namespace.
- ** They are used to indicate that the process should wait no time (return
- ** immediately) or wait forever (never time out), respectively.
- ***********************************************************************/
- #define PR_INTERVAL_NO_WAIT 0UL
- #define PR_INTERVAL_NO_TIMEOUT 0xffffffffUL
- /**********************************************************************/
- /****************************** FUNCTIONS *****************************/
- /**********************************************************************/
- /***********************************************************************
- ** FUNCTION: PR_IntervalNow
- ** DESCRIPTION:
- ** Return the value of NSPR's free running interval timer. That timer
- ** can be used to establish epochs and determine intervals (be computing
- ** the difference between two times).
- ** INPUTS: void
- ** OUTPUTS: void
- ** RETURN: PRIntervalTime
- **
- ** SIDE EFFECTS:
- ** None
- ** RESTRICTIONS:
- ** The units of PRIntervalTime are platform dependent. They are chosen
- ** such that they are appropriate for the host OS, yet provide sufficient
- ** resolution and period to be useful to clients.
- ** MEMORY: N/A
- ** ALGORITHM: Platform dependent
- ***********************************************************************/
- NSPR_API(PRIntervalTime) PR_IntervalNow(void);
- /***********************************************************************
- ** FUNCTION: PR_TicksPerSecond
- ** DESCRIPTION:
- ** Return the number of ticks per second for PR_IntervalNow's clock.
- ** The value will be in the range [PR_INTERVAL_MIN..PR_INTERVAL_MAX].
- ** INPUTS: void
- ** OUTPUTS: void
- ** RETURN: PRUint32
- **
- ** SIDE EFFECTS:
- ** None
- ** RESTRICTIONS:
- ** None
- ** MEMORY: N/A
- ** ALGORITHM: N/A
- ***********************************************************************/
- NSPR_API(PRUint32) PR_TicksPerSecond(void);
- /***********************************************************************
- ** FUNCTION: PR_SecondsToInterval
- ** PR_MillisecondsToInterval
- ** PR_MicrosecondsToInterval
- ** DESCRIPTION:
- ** Convert standard clock units to platform dependent intervals.
- ** INPUTS: PRUint32
- ** OUTPUTS: void
- ** RETURN: PRIntervalTime
- **
- ** SIDE EFFECTS:
- ** None
- ** RESTRICTIONS:
- ** Conversion may cause overflow, which is not reported.
- ** MEMORY: N/A
- ** ALGORITHM: N/A
- ***********************************************************************/
- NSPR_API(PRIntervalTime) PR_SecondsToInterval(PRUint32 seconds);
- NSPR_API(PRIntervalTime) PR_MillisecondsToInterval(PRUint32 milli);
- NSPR_API(PRIntervalTime) PR_MicrosecondsToInterval(PRUint32 micro);
- /***********************************************************************
- ** FUNCTION: PR_IntervalToSeconds
- ** PR_IntervalToMilliseconds
- ** PR_IntervalToMicroseconds
- ** DESCRIPTION:
- ** Convert platform dependent intervals to standard clock units.
- ** INPUTS: PRIntervalTime
- ** OUTPUTS: void
- ** RETURN: PRUint32
- **
- ** SIDE EFFECTS:
- ** None
- ** RESTRICTIONS:
- ** Conversion may cause overflow, which is not reported.
- ** MEMORY: N/A
- ** ALGORITHM: N/A
- ***********************************************************************/
- NSPR_API(PRUint32) PR_IntervalToSeconds(PRIntervalTime ticks);
- NSPR_API(PRUint32) PR_IntervalToMilliseconds(PRIntervalTime ticks);
- NSPR_API(PRUint32) PR_IntervalToMicroseconds(PRIntervalTime ticks);
- PR_END_EXTERN_C
- #endif /* !defined(prinrval_h) */
- /* prinrval.h */