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      1 /* Portions are Copyright (C) 2011 Google Inc */
      2 /* ***** BEGIN LICENSE BLOCK *****
      3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
      4  *
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      6  * 1.1 (the "License"); you may not use this file except in compliance with
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     11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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     13  * License.
     14  *
     15  * The Original Code is the Netscape Portable Runtime (NSPR).
     16  *
     17  * The Initial Developer of the Original Code is
     18  * Netscape Communications Corporation.
     19  * Portions created by the Initial Developer are Copyright (C) 1998-2000
     20  * the Initial Developer. All Rights Reserved.
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     25  * either the GNU General Public License Version 2 or later (the "GPL"), or
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     36  * ***** END LICENSE BLOCK ***** */
     37 
     38 /*
     39  *---------------------------------------------------------------------------
     40  *
     41  * prtime.h --
     42  *
     43  *     NSPR date and time functions
     44  * CVS revision 3.10
     45  * This file contains definitions of NSPR's basic types required by
     46  * prtime.cc. These types have been copied over from the following NSPR
     47  * files prtime.h, prtypes.h(CVS revision 3.35), prlong.h(CVS revision 3.13)
     48  *
     49  *---------------------------------------------------------------------------
     50  */
     51 
     52 #ifndef BASE_PRTIME_H__
     53 #define BASE_PRTIME_H__
     54 
     55 #include <stdint.h>
     56 
     57 #include "base/base_export.h"
     58 
     59 typedef int8_t PRInt8;
     60 typedef int16_t PRInt16;
     61 typedef int32_t PRInt32;
     62 typedef int64_t PRInt64;
     63 typedef int PRIntn;
     64 
     65 typedef PRIntn PRBool;
     66 #define PR_TRUE 1
     67 #define PR_FALSE 0
     68 
     69 typedef enum { PR_FAILURE = -1, PR_SUCCESS = 0 } PRStatus;
     70 
     71 #define PR_ASSERT DCHECK
     72 #define PR_CALLBACK
     73 #define PR_INT16_MAX 32767
     74 #define NSPR_API(__type) extern __type
     75 
     76 /*
     77  * Long-long (64-bit signed integer type) support macros used by
     78  * PR_ImplodeTime().
     79  * See http://lxr.mozilla.org/nspr/source/pr/include/prlong.h
     80  */
     81 
     82 #define LL_I2L(l, i) ((l) = (PRInt64)(i))
     83 #define LL_MUL(r, a, b) ((r) = (a) * (b))
     84 #define LL_ADD(r, a, b) ((r) = (a) + (b))
     85 #define LL_SUB(r, a, b) ((r) = (a) - (b))
     86 
     87 /**********************************************************************/
     88 /************************* TYPES AND CONSTANTS ************************/
     89 /**********************************************************************/
     90 
     91 #define PR_MSEC_PER_SEC		1000UL
     92 #define PR_USEC_PER_SEC		1000000UL
     93 #define PR_NSEC_PER_SEC		1000000000UL
     94 #define PR_USEC_PER_MSEC	1000UL
     95 #define PR_NSEC_PER_MSEC	1000000UL
     96 
     97 /*
     98  * PRTime --
     99  *
    100  *     NSPR represents basic time as 64-bit signed integers relative
    101  *     to midnight (00:00:00), January 1, 1970 Greenwich Mean Time (GMT).
    102  *     (GMT is also known as Coordinated Universal Time, UTC.)
    103  *     The units of time are in microseconds. Negative times are allowed
    104  *     to represent times prior to the January 1970 epoch. Such values are
    105  *     intended to be exported to other systems or converted to human
    106  *     readable form.
    107  *
    108  *     Notes on porting: PRTime corresponds to time_t in ANSI C.  NSPR 1.0
    109  *     simply uses PRInt64.
    110  */
    111 
    112 typedef PRInt64 PRTime;
    113 
    114 /*
    115  * Time zone and daylight saving time corrections applied to GMT to
    116  * obtain the local time of some geographic location
    117  */
    118 
    119 typedef struct PRTimeParameters {
    120     PRInt32 tp_gmt_offset;     /* the offset from GMT in seconds */
    121     PRInt32 tp_dst_offset;     /* contribution of DST in seconds */
    122 } PRTimeParameters;
    123 
    124 /*
    125  * PRExplodedTime --
    126  *
    127  *     Time broken down into human-readable components such as year, month,
    128  *     day, hour, minute, second, and microsecond.  Time zone and daylight
    129  *     saving time corrections may be applied.  If they are applied, the
    130  *     offsets from the GMT must be saved in the 'tm_params' field so that
    131  *     all the information is available to reconstruct GMT.
    132  *
    133  *     Notes on porting: PRExplodedTime corrresponds to struct tm in
    134  *     ANSI C, with the following differences:
    135  *       - an additional field tm_usec;
    136  *       - replacing tm_isdst by tm_params;
    137  *       - the month field is spelled tm_month, not tm_mon;
    138  *       - we use absolute year, AD, not the year since 1900.
    139  *     The corresponding type in NSPR 1.0 is called PRTime.  Below is
    140  *     a table of date/time type correspondence in the three APIs:
    141  *         API          time since epoch          time in components
    142  *       ANSI C             time_t                  struct tm
    143  *       NSPR 1.0           PRInt64                   PRTime
    144  *       NSPR 2.0           PRTime                  PRExplodedTime
    145  */
    146 
    147 typedef struct PRExplodedTime {
    148     PRInt32 tm_usec;		    /* microseconds past tm_sec (0-99999)  */
    149     PRInt32 tm_sec;             /* seconds past tm_min (0-61, accomodating
    150                                    up to two leap seconds) */
    151     PRInt32 tm_min;             /* minutes past tm_hour (0-59) */
    152     PRInt32 tm_hour;            /* hours past tm_day (0-23) */
    153     PRInt32 tm_mday;            /* days past tm_mon (1-31, note that it
    154 				                starts from 1) */
    155     PRInt32 tm_month;           /* months past tm_year (0-11, Jan = 0) */
    156     PRInt16 tm_year;            /* absolute year, AD (note that we do not
    157 				                count from 1900) */
    158 
    159     PRInt8 tm_wday;		        /* calculated day of the week
    160 				                (0-6, Sun = 0) */
    161     PRInt16 tm_yday;            /* calculated day of the year
    162 				                (0-365, Jan 1 = 0) */
    163 
    164     PRTimeParameters tm_params;  /* time parameters used by conversion */
    165 } PRExplodedTime;
    166 
    167 /*
    168  * PRTimeParamFn --
    169  *
    170  *     A function of PRTimeParamFn type returns the time zone and
    171  *     daylight saving time corrections for some geographic location,
    172  *     given the current time in GMT.  The input argument gmt should
    173  *     point to a PRExplodedTime that is in GMT, i.e., whose
    174  *     tm_params contains all 0's.
    175  *
    176  *     For any time zone other than GMT, the computation is intended to
    177  *     consist of two steps:
    178  *       - Figure out the time zone correction, tp_gmt_offset.  This number
    179  *         usually depends on the geographic location only.  But it may
    180  *         also depend on the current time.  For example, all of China
    181  *         is one time zone right now.  But this situation may change
    182  *         in the future.
    183  *       - Figure out the daylight saving time correction, tp_dst_offset.
    184  *         This number depends on both the geographic location and the
    185  *         current time.  Most of the DST rules are expressed in local
    186  *         current time.  If so, one should apply the time zone correction
    187  *         to GMT before applying the DST rules.
    188  */
    189 
    190 typedef PRTimeParameters (PR_CALLBACK *PRTimeParamFn)(const PRExplodedTime *gmt);
    191 
    192 /**********************************************************************/
    193 /****************************** FUNCTIONS *****************************/
    194 /**********************************************************************/
    195 
    196 NSPR_API(PRTime)
    197 PR_ImplodeTime(const PRExplodedTime *exploded);
    198 
    199 /*
    200  * Adjust exploded time to normalize field overflows after manipulation.
    201  * Note that the following fields of PRExplodedTime should not be
    202  * manipulated:
    203  *   - tm_month and tm_year: because the number of days in a month and
    204  *     number of days in a year are not constant, it is ambiguous to
    205  *     manipulate the month and year fields, although one may be tempted
    206  *     to.  For example, what does "a month from January 31st" mean?
    207  *   - tm_wday and tm_yday: these fields are calculated by NSPR.  Users
    208  *     should treat them as "read-only".
    209  */
    210 
    211 NSPR_API(void) PR_NormalizeTime(
    212     PRExplodedTime *exploded, PRTimeParamFn params);
    213 
    214 /**********************************************************************/
    215 /*********************** TIME PARAMETER FUNCTIONS *********************/
    216 /**********************************************************************/
    217 
    218 /* Time parameters that represent Greenwich Mean Time */
    219 NSPR_API(PRTimeParameters) PR_GMTParameters(const PRExplodedTime *gmt);
    220 
    221 /*
    222  * This parses a time/date string into a PRTime
    223  * (microseconds after "1-Jan-1970 00:00:00 GMT").
    224  * It returns PR_SUCCESS on success, and PR_FAILURE
    225  * if the time/date string can't be parsed.
    226  *
    227  * Many formats are handled, including:
    228  *
    229  *   14 Apr 89 03:20:12
    230  *   14 Apr 89 03:20 GMT
    231  *   Fri, 17 Mar 89 4:01:33
    232  *   Fri, 17 Mar 89 4:01 GMT
    233  *   Mon Jan 16 16:12 PDT 1989
    234  *   Mon Jan 16 16:12 +0130 1989
    235  *   6 May 1992 16:41-JST (Wednesday)
    236  *   22-AUG-1993 10:59:12.82
    237  *   22-AUG-1993 10:59pm
    238  *   22-AUG-1993 12:59am
    239  *   22-AUG-1993 12:59 PM
    240  *   Friday, August 04, 1995 3:54 PM
    241  *   06/21/95 04:24:34 PM
    242  *   20/06/95 21:07
    243  *   95-06-08 19:32:48 EDT
    244  *   1995-06-17T23:11:25.342156Z
    245  *
    246  * If the input string doesn't contain a description of the timezone,
    247  * we consult the `default_to_gmt' to decide whether the string should
    248  * be interpreted relative to the local time zone (PR_FALSE) or GMT (PR_TRUE).
    249  * The correct value for this argument depends on what standard specified
    250  * the time string which you are parsing.
    251  */
    252 
    253 /*
    254  * This is the only funtion that should be called from outside base, and only
    255  * from the unit test.
    256  */
    257 
    258 BASE_EXPORT PRStatus PR_ParseTimeString (
    259 	const char *string,
    260 	PRBool default_to_gmt,
    261 	PRTime *result);
    262 
    263 #endif  // BASE_PRTIME_H__
    264