/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* * 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 Netscape are * Copyright (C) 1998-2000 Netscape Communications Corporation. All * Rights Reserved. * * Contributor(s): * * Alternatively, the contents of this file may be used under the * terms of the GNU General Public License Version 2 or later (the * "GPL"), in which case the provisions of the GPL are applicable * instead of those above. If you wish to allow use of your * version of this file only under the terms of the GPL and not to * allow others to use your version of this file under the MPL, * indicate your decision by deleting the provisions above and * replace them with the notice and other provisions required by * the GPL. If you do not delete the provisions above, a recipient * may use your version of this file under either the MPL or the * GPL. */ /* ** 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 */