/* -*- 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 ***** */ /* *---------------------------------------------------------------------- * * prtime.h -- * * NSPR date and time functions * *----------------------------------------------------------------------- */ #ifndef prtime_h___ #define prtime_h___ #include "prlong.h" PR_BEGIN_EXTERN_C /**********************************************************************/ /************************* TYPES AND CONSTANTS ************************/ /**********************************************************************/ #define PR_MSEC_PER_SEC 1000UL #define PR_USEC_PER_SEC 1000000UL #define PR_NSEC_PER_SEC 1000000000UL #define PR_USEC_PER_MSEC 1000UL #define PR_NSEC_PER_MSEC 1000000UL /* * PRTime -- * * NSPR represents basic time as 64-bit signed integers relative * to midnight (00:00:00), January 1, 1970 Greenwich Mean Time (GMT). * (GMT is also known as Coordinated Universal Time, UTC.) * The units of time are in microseconds. Negative times are allowed * to represent times prior to the January 1970 epoch. Such values are * intended to be exported to other systems or converted to human * readable form. * * Notes on porting: PRTime corresponds to time_t in ANSI C. NSPR 1.0 * simply uses PRInt64. */ typedef PRInt64 PRTime; /* * Time zone and daylight saving time corrections applied to GMT to * obtain the local time of some geographic location */ typedef struct PRTimeParameters { PRInt32 tp_gmt_offset; /* the offset from GMT in seconds */ PRInt32 tp_dst_offset; /* contribution of DST in seconds */ } PRTimeParameters; /* * PRExplodedTime -- * * Time broken down into human-readable components such as year, month, * day, hour, minute, second, and microsecond. Time zone and daylight * saving time corrections may be applied. If they are applied, the * offsets from the GMT must be saved in the 'tm_params' field so that * all the information is available to reconstruct GMT. * * Notes on porting: PRExplodedTime corrresponds to struct tm in * ANSI C, with the following differences: * - an additional field tm_usec; * - replacing tm_isdst by tm_params; * - the month field is spelled tm_month, not tm_mon; * - we use absolute year, AD, not the year since 1900. * The corresponding type in NSPR 1.0 is called PRTime. Below is * a table of date/time type correspondence in the three APIs: * API time since epoch time in components * ANSI C time_t struct tm * NSPR 1.0 PRInt64 PRTime * NSPR 2.0 PRTime PRExplodedTime */ typedef struct PRExplodedTime { PRInt32 tm_usec; /* microseconds past tm_sec (0-99999) */ PRInt32 tm_sec; /* seconds past tm_min (0-61, accomodating up to two leap seconds) */ PRInt32 tm_min; /* minutes past tm_hour (0-59) */ PRInt32 tm_hour; /* hours past tm_day (0-23) */ PRInt32 tm_mday; /* days past tm_mon (1-31, note that it starts from 1) */ PRInt32 tm_month; /* months past tm_year (0-11, Jan = 0) */ PRInt16 tm_year; /* absolute year, AD (note that we do not count from 1900) */ PRInt8 tm_wday; /* calculated day of the week (0-6, Sun = 0) */ PRInt16 tm_yday; /* calculated day of the year (0-365, Jan 1 = 0) */ PRTimeParameters tm_params; /* time parameters used by conversion */ } PRExplodedTime; /* * PRTimeParamFn -- * * A function of PRTimeParamFn type returns the time zone and * daylight saving time corrections for some geographic location, * given the current time in GMT. The input argument gmt should * point to a PRExplodedTime that is in GMT, i.e., whose * tm_params contains all 0's. * * For any time zone other than GMT, the computation is intended to * consist of two steps: * - Figure out the time zone correction, tp_gmt_offset. This number * usually depends on the geographic location only. But it may * also depend on the current time. For example, all of China * is one time zone right now. But this situation may change * in the future. * - Figure out the daylight saving time correction, tp_dst_offset. * This number depends on both the geographic location and the * current time. Most of the DST rules are expressed in local * current time. If so, one should apply the time zone correction * to GMT before applying the DST rules. */ typedef PRTimeParameters (PR_CALLBACK *PRTimeParamFn)(const PRExplodedTime *gmt); /**********************************************************************/ /****************************** FUNCTIONS *****************************/ /**********************************************************************/ /* * The PR_Now routine returns the current time relative to the * epoch, midnight, January 1, 1970 UTC. The units of the returned * value are microseconds since the epoch. * * The values returned are not guaranteed to advance in a linear fashion * due to the application of time correction protocols which synchronize * computer clocks to some external time source. Consequently it should * not be depended on for interval timing. * * The implementation is machine dependent. * Cf. time_t time(time_t *tp) in ANSI C. */ #if defined(HAVE_WATCOM_BUG_2) PRTime __pascal __export __loadds #else NSPR_API(PRTime) #endif PR_Now(void); /* * Expand time binding it to time parameters provided by PRTimeParamFn. * The calculation is envisoned to proceed in the following steps: * - From given PRTime, calculate PRExplodedTime in GMT * - Apply the given PRTimeParamFn to the GMT that we just calculated * to obtain PRTimeParameters. * - Add the PRTimeParameters offsets to GMT to get the local time * as PRExplodedTime. */ NSPR_API(void) PR_ExplodeTime( PRTime usecs, PRTimeParamFn params, PRExplodedTime *exploded); /* Reverse operation of PR_ExplodeTime */ #if defined(HAVE_WATCOM_BUG_2) PRTime __pascal __export __loadds #else NSPR_API(PRTime) #endif PR_ImplodeTime(const PRExplodedTime *exploded); /* * Adjust exploded time to normalize field overflows after manipulation. * Note that the following fields of PRExplodedTime should not be * manipulated: * - tm_month and tm_year: because the number of days in a month and * number of days in a year are not constant, it is ambiguous to * manipulate the month and year fields, although one may be tempted * to. For example, what does "a month from January 31st" mean? * - tm_wday and tm_yday: these fields are calculated by NSPR. Users * should treat them as "read-only". */ NSPR_API(void) PR_NormalizeTime( PRExplodedTime *exploded, PRTimeParamFn params); /**********************************************************************/ /*********************** TIME PARAMETER FUNCTIONS *********************/ /**********************************************************************/ /* Time parameters that suit current host machine */ NSPR_API(PRTimeParameters) PR_LocalTimeParameters(const PRExplodedTime *gmt); /* Time parameters that represent Greenwich Mean Time */ NSPR_API(PRTimeParameters) PR_GMTParameters(const PRExplodedTime *gmt); /* * Time parameters that represent the US Pacific Time Zone, with the * current daylight saving time rules (for testing only) */ NSPR_API(PRTimeParameters) PR_USPacificTimeParameters(const PRExplodedTime *gmt); /* * This parses a time/date string into a PRTime * (microseconds after "1-Jan-1970 00:00:00 GMT"). * It returns PR_SUCCESS on success, and PR_FAILURE * if the time/date string can't be parsed. * * Many formats are handled, including: * * 14 Apr 89 03:20:12 * 14 Apr 89 03:20 GMT * Fri, 17 Mar 89 4:01:33 * Fri, 17 Mar 89 4:01 GMT * Mon Jan 16 16:12 PDT 1989 * Mon Jan 16 16:12 +0130 1989 * 6 May 1992 16:41-JST (Wednesday) * 22-AUG-1993 10:59:12.82 * 22-AUG-1993 10:59pm * 22-AUG-1993 12:59am * 22-AUG-1993 12:59 PM * Friday, August 04, 1995 3:54 PM * 06/21/95 04:24:34 PM * 20/06/95 21:07 * 95-06-08 19:32:48 EDT * * If the input string doesn't contain a description of the timezone, * we consult the `default_to_gmt' to decide whether the string should * be interpreted relative to the local time zone (PR_FALSE) or GMT (PR_TRUE). * The correct value for this argument depends on what standard specified * the time string which you are parsing. */ NSPR_API(PRStatus) PR_ParseTimeString ( const char *string, PRBool default_to_gmt, PRTime *result); /* * FIXME: should we also have a formatting function, such as asctime, ctime, * and strftime in standard C library? But this would involve * internationalization issues. Might want to provide a US English version. */ /**********************************************************************/ /*********************** OLD COMPATIBILITYFUNCTIONS *******************/ /**********************************************************************/ #ifndef NO_NSPR_10_SUPPORT /* Format a time value into a buffer. Same semantics as strftime() */ NSPR_API(PRUint32) PR_FormatTime(char *buf, int buflen, const char *fmt, const PRExplodedTime *tm); /* Format a time value into a buffer. Time is always in US English format, regardless * of locale setting. */ NSPR_API(PRUint32) PR_FormatTimeUSEnglish( char* buf, PRUint32 bufSize, const char* format, const PRExplodedTime* tm ); #endif /* NO_NSPR_10_SUPPORT */ PR_END_EXTERN_C #endif /* prtime_h___ */