icuSources/i18n/unicode/ucal.h

   1 /*
   2  *******************************************************************************
   3  * Copyright (C) 1996-2012, International Business Machines Corporation and
   4  * others. All Rights Reserved.
   5  *******************************************************************************
   6  */
   7
   8 #ifndef UCAL_H
   9 #define UCAL_H
  10
  11 #include "unicode/utypes.h"
  12 #include "unicode/uenum.h"
  13 #include "unicode/uloc.h"
  14 #include "unicode/localpointer.h"
  15
  16 #if !UCONFIG_NO_FORMATTING
  17
  18 /**
  19  * \file
  20  * \brief C API: Calendar
  21  *
  22  * <h2>Calendar C API</h2>
  23  *
  24  * UCalendar C API is used  for converting between a <code>UDate</code> object
  25  * and a set of integer fields such as <code>UCAL_YEAR</code>, <code>UCAL_MONTH</code>,
  26  * <code>UCAL_DAY</code>, <code>UCAL_HOUR</code>, and so on.
  27  * (A <code>UDate</code> object represents a specific instant in
  28  * time with millisecond precision. See UDate
  29  * for information about the <code>UDate</code> .)
  30  *
  31  * <p>
  32  * Types of <code>UCalendar</code> interpret a <code>UDate</code>
  33  * according to the rules of a specific calendar system. The U_STABLE
  34  * provides the enum UCalendarType with UCAL_TRADITIONAL and
  35  * UCAL_GREGORIAN.
  36  * <p>
  37  * Like other locale-sensitive C API, calendar API  provides a
  38  * function, <code>ucal_open()</code>, which returns a pointer to
  39  * <code>UCalendar</code> whose time fields have been initialized
  40  * with the current date and time. We need to specify the type of
  41  * calendar to be opened and the  timezoneId.
  42  * \htmlonly<blockquote>\endhtmlonly
  43  * <pre>
  44  * \code
  45  * UCalendar *caldef;
  46  * UChar *tzId;
  47  * UErrorCode status;
  48  * tzId=(UChar*)malloc(sizeof(UChar) * (strlen("PST") +1) );
  49  * u_uastrcpy(tzId, "PST");
  50  * caldef=ucal_open(tzID, u_strlen(tzID), NULL, UCAL_TRADITIONAL, &status);
  51  * \endcode
  52  * </pre>
  53  * \htmlonly</blockquote>\endhtmlonly
  54  *
  55  * <p>
  56  * A <code>UCalendar</code> object can produce all the time field values
  57  * needed to implement the date-time formatting for a particular language
  58  * and calendar style (for example, Japanese-Gregorian, Japanese-Traditional).
  59  *
  60  * <p>
  61  * When computing a <code>UDate</code> from time fields, two special circumstances
  62  * may arise: there may be insufficient information to compute the
  63  * <code>UDate</code> (such as only year and month but no day in the month),
  64  * or there may be inconsistent information (such as "Tuesday, July 15, 1996"
  65  * -- July 15, 1996 is actually a Monday).
  66  *
  67  * <p>
  68  * <strong>Insufficient information.</strong> The calendar will use default
  69  * information to specify the missing fields. This may vary by calendar; for
  70  * the Gregorian calendar, the default for a field is the same as that of the
  71  * start of the epoch: i.e., UCAL_YEAR = 1970, UCAL_MONTH = JANUARY, UCAL_DATE = 1, etc.
  72  *
  73  * <p>
  74  * <strong>Inconsistent information.</strong> If fields conflict, the calendar
  75  * will give preference to fields set more recently. For example, when
  76  * determining the day, the calendar will look for one of the following
  77  * combinations of fields.  The most recent combination, as determined by the
  78  * most recently set single field, will be used.
  79  *
  80  * \htmlonly<blockquote>\endhtmlonly
  81  * <pre>
  82  * \code
  83  * UCAL_MONTH + UCAL_DAY_OF_MONTH
  84  * UCAL_MONTH + UCAL_WEEK_OF_MONTH + UCAL_DAY_OF_WEEK
  85  * UCAL_MONTH + UCAL_DAY_OF_WEEK_IN_MONTH + UCAL_DAY_OF_WEEK
  86  * UCAL_DAY_OF_YEAR
  87  * UCAL_DAY_OF_WEEK + UCAL_WEEK_OF_YEAR
  88  * \endcode
  89  * </pre>
  90  * \htmlonly</blockquote>\endhtmlonly
  91  *
  92  * For the time of day:
  93  *
  94  * \htmlonly<blockquote>\endhtmlonly
  95  * <pre>
  96  * \code
  97  * UCAL_HOUR_OF_DAY
  98  * UCAL_AM_PM + UCAL_HOUR
  99  * \endcode
 100  * </pre>
 101  * \htmlonly</blockquote>\endhtmlonly
 102  *
 103  * <p>
 104  * <strong>Note:</strong> for some non-Gregorian calendars, different
 105  * fields may be necessary for complete disambiguation. For example, a full
 106  * specification of the historial Arabic astronomical calendar requires year,
 107  * month, day-of-month <em>and</em> day-of-week in some cases.
 108  *
 109  * <p>
 110  * <strong>Note:</strong> There are certain possible ambiguities in
 111  * interpretation of certain singular times, which are resolved in the
 112  * following ways:
 113  * <ol>
 114  *     <li> 24:00:00 "belongs" to the following day. That is,
 115  *          23:59 on Dec 31, 1969 &lt; 24:00 on Jan 1, 1970 &lt; 24:01:00 on Jan 1, 1970
 116  *
 117  *     <li> Although historically not precise, midnight also belongs to "am",
 118  *          and noon belongs to "pm", so on the same day,
 119  *          12:00 am (midnight) &lt; 12:01 am, and 12:00 pm (noon) &lt; 12:01 pm
 120  * </ol>
 121  *
 122  * <p>
 123  * The date or time format strings are not part of the definition of a
 124  * calendar, as those must be modifiable or overridable by the user at
 125  * runtime. Use {@link DateFormat}
 126  * to format dates.
 127  *
 128  * <p>
 129  * <code>Calendar</code> provides an API for field "rolling", where fields
 130  * can be incremented or decremented, but wrap around. For example, rolling the
 131  * month up in the date <code>December 12, <b>1996</b></code> results in
 132  * <code>January 12, <b>1996</b></code>.
 133  *
 134  * <p>
 135  * <code>Calendar</code> also provides a date arithmetic function for
 136  * adding the specified (signed) amount of time to a particular time field.
 137  * For example, subtracting 5 days from the date <code>September 12, 1996</code>
 138  * results in <code>September 7, 1996</code>.
 139  *
 140  * @stable ICU 2.0
 141  */
 142
 143 /**
 144  * The time zone ID reserved for unknown time zone.
 145  * @stable ICU 4.8
 146  */
 147 #define UCAL_UNKNOWN_ZONE_ID "Etc/Unknown"
 148
 149 /** A calendar.
 150  *  For usage in C programs.
 151  * @stable ICU 2.0
 152  */
 153 typedef void* UCalendar;
 154
 155 /** Possible types of UCalendars
 156  * @stable ICU 2.0
 157  */
 158 enum UCalendarType {
 159   /**
 160    * Despite the name, UCAL_TRADITIONAL designates the locale's default calendar,
 161    * which may be the Gregorian calendar or some other calendar.
 162    * @stable ICU 2.0
 163    */
 164   UCAL_TRADITIONAL,
 165   /**
 166    * A better name for UCAL_TRADITIONAL.
 167    * @stable ICU 4.2
 168    */
 169   UCAL_DEFAULT = UCAL_TRADITIONAL,
 170   /**
 171    * Unambiguously designates the Gregorian calendar for the locale.
 172    * @stable ICU 2.0
 173    */
 174   UCAL_GREGORIAN
 175 };
 176
 177 /** @stable ICU 2.0 */
 178 typedef enum UCalendarType UCalendarType;
 179
 180 /** Possible fields in a UCalendar
 181  * @stable ICU 2.0
 182  */
 183 enum UCalendarDateFields {
 184   /**
 185    * Field number indicating the era, e.g., AD or BC in the Gregorian (Julian) calendar.
 186    * This is a calendar-specific value.
 187    * @stable ICU 2.6
 188    */
 189   UCAL_ERA,
 190
 191   /**
 192    * Field number indicating the year. This is a calendar-specific value.
 193    * @stable ICU 2.6
 194    */
 195   UCAL_YEAR,
 196
 197   /**
 198    * Field number indicating the month. This is a calendar-specific value.
 199    * The first month of the year is
 200    * <code>JANUARY</code>; the last depends on the number of months in a year.
 201    * @see #UCAL_JANUARY
 202    * @see #UCAL_FEBRUARY
 203    * @see #UCAL_MARCH
 204    * @see #UCAL_APRIL
 205    * @see #UCAL_MAY
 206    * @see #UCAL_JUNE
 207    * @see #UCAL_JULY
 208    * @see #UCAL_AUGUST
 209    * @see #UCAL_SEPTEMBER
 210    * @see #UCAL_OCTOBER
 211    * @see #UCAL_NOVEMBER
 212    * @see #UCAL_DECEMBER
 213    * @see #UCAL_UNDECIMBER
 214    * @stable ICU 2.6
 215    */
 216   UCAL_MONTH,
 217
 218   /**
 219    * Field number indicating the
 220    * week number within the current year.  The first week of the year, as
 221    * defined by <code>UCAL_FIRST_DAY_OF_WEEK</code> and <code>UCAL_MINIMAL_DAYS_IN_FIRST_WEEK</code>
 222    * attributes, has value 1.  Subclasses define
 223    * the value of <code>UCAL_WEEK_OF_YEAR</code> for days before the first week of
 224    * the year.
 225    * @see ucal_getAttribute
 226    * @see ucal_setAttribute
 227    * @stable ICU 2.6
 228    */
 229   UCAL_WEEK_OF_YEAR,
 230
 231  /**
 232    * Field number indicating the
 233    * week number within the current month.  The first week of the month, as
 234    * defined by <code>UCAL_FIRST_DAY_OF_WEEK</code> and <code>UCAL_MINIMAL_DAYS_IN_FIRST_WEEK</code>
 235    * attributes, has value 1.  Subclasses define
 236    * the value of <code>WEEK_OF_MONTH</code> for days before the first week of
 237    * the month.
 238    * @see ucal_getAttribute
 239    * @see ucal_setAttribute
 240    * @see #UCAL_FIRST_DAY_OF_WEEK
 241    * @see #UCAL_MINIMAL_DAYS_IN_FIRST_WEEK
 242    * @stable ICU 2.6
 243    */
 244   UCAL_WEEK_OF_MONTH,
 245
 246  /**
 247    * Field number indicating the
 248    * day of the month. This is a synonym for <code>DAY_OF_MONTH</code>.
 249    * The first day of the month has value 1.
 250    * @see #UCAL_DAY_OF_MONTH
 251    * @stable ICU 2.6
 252    */
 253   UCAL_DATE,
 254
 255  /**
 256    * Field number indicating the day
 257    * number within the current year.  The first day of the year has value 1.
 258    * @stable ICU 2.6
 259    */
 260   UCAL_DAY_OF_YEAR,
 261
 262  /**
 263    * Field number indicating the day
 264    * of the week.  This field takes values <code>SUNDAY</code>,
 265    * <code>MONDAY</code>, <code>TUESDAY</code>, <code>WEDNESDAY</code>,
 266    * <code>THURSDAY</code>, <code>FRIDAY</code>, and <code>SATURDAY</code>.
 267    * @see #UCAL_SUNDAY
 268    * @see #UCAL_MONDAY
 269    * @see #UCAL_TUESDAY
 270    * @see #UCAL_WEDNESDAY
 271    * @see #UCAL_THURSDAY
 272    * @see #UCAL_FRIDAY
 273    * @see #UCAL_SATURDAY
 274    * @stable ICU 2.6
 275    */
 276   UCAL_DAY_OF_WEEK,
 277
 278  /**
 279    * Field number indicating the
 280    * ordinal number of the day of the week within the current month. Together
 281    * with the <code>DAY_OF_WEEK</code> field, this uniquely specifies a day
 282    * within a month.  Unlike <code>WEEK_OF_MONTH</code> and
 283    * <code>WEEK_OF_YEAR</code>, this field's value does <em>not</em> depend on
 284    * <code>getFirstDayOfWeek()</code> or
 285    * <code>getMinimalDaysInFirstWeek()</code>.  <code>DAY_OF_MONTH 1</code>
 286    * through <code>7</code> always correspond to <code>DAY_OF_WEEK_IN_MONTH
 287    * 1</code>; <code>8</code> through <code>15</code> correspond to
 288    * <code>DAY_OF_WEEK_IN_MONTH 2</code>, and so on.
 289    * <code>DAY_OF_WEEK_IN_MONTH 0</code> indicates the week before
 290    * <code>DAY_OF_WEEK_IN_MONTH 1</code>.  Negative values count back from the
 291    * end of the month, so the last Sunday of a month is specified as
 292    * <code>DAY_OF_WEEK = SUNDAY, DAY_OF_WEEK_IN_MONTH = -1</code>.  Because
 293    * negative values count backward they will usually be aligned differently
 294    * within the month than positive values.  For example, if a month has 31
 295    * days, <code>DAY_OF_WEEK_IN_MONTH -1</code> will overlap
 296    * <code>DAY_OF_WEEK_IN_MONTH 5</code> and the end of <code>4</code>.
 297    * @see #UCAL_DAY_OF_WEEK
 298    * @see #UCAL_WEEK_OF_MONTH
 299    * @stable ICU 2.6
 300    */
 301   UCAL_DAY_OF_WEEK_IN_MONTH,
 302
 303  /**
 304    * Field number indicating
 305    * whether the <code>HOUR</code> is before or after noon.
 306    * E.g., at 10:04:15.250 PM the <code>AM_PM</code> is <code>PM</code>.
 307    * @see #UCAL_AM
 308    * @see #UCAL_PM
 309    * @see #UCAL_HOUR
 310    * @stable ICU 2.6
 311    */
 312   UCAL_AM_PM,
 313
 314  /**
 315    * Field number indicating the
 316    * hour of the morning or afternoon. <code>HOUR</code> is used for the 12-hour
 317    * clock.
 318    * E.g., at 10:04:15.250 PM the <code>HOUR</code> is 10.
 319    * @see #UCAL_AM_PM
 320    * @see #UCAL_HOUR_OF_DAY
 321    * @stable ICU 2.6
 322    */
 323   UCAL_HOUR,
 324
 325  /**
 326    * Field number indicating the
 327    * hour of the day. <code>HOUR_OF_DAY</code> is used for the 24-hour clock.
 328    * E.g., at 10:04:15.250 PM the <code>HOUR_OF_DAY</code> is 22.
 329    * @see #UCAL_HOUR
 330    * @stable ICU 2.6
 331    */
 332   UCAL_HOUR_OF_DAY,
 333
 334  /**
 335    * Field number indicating the
 336    * minute within the hour.
 337    * E.g., at 10:04:15.250 PM the <code>UCAL_MINUTE</code> is 4.
 338    * @stable ICU 2.6
 339    */
 340   UCAL_MINUTE,
 341
 342  /**
 343    * Field number indicating the
 344    * second within the minute.
 345    * E.g., at 10:04:15.250 PM the <code>UCAL_SECOND</code> is 15.
 346    * @stable ICU 2.6
 347    */
 348   UCAL_SECOND,
 349
 350  /**
 351    * Field number indicating the
 352    * millisecond within the second.
 353    * E.g., at 10:04:15.250 PM the <code>UCAL_MILLISECOND</code> is 250.
 354    * @stable ICU 2.6
 355    */
 356   UCAL_MILLISECOND,
 357
 358  /**
 359    * Field number indicating the
 360    * raw offset from GMT in milliseconds.
 361    * @stable ICU 2.6
 362    */
 363   UCAL_ZONE_OFFSET,
 364
 365  /**
 366    * Field number indicating the
 367    * daylight savings offset in milliseconds.
 368    * @stable ICU 2.6
 369    */
 370   UCAL_DST_OFFSET,
 371
 372  /**
 373    * Field number
 374    * indicating the extended year corresponding to the
 375    * <code>UCAL_WEEK_OF_YEAR</code> field.  This may be one greater or less
 376    * than the value of <code>UCAL_EXTENDED_YEAR</code>.
 377    * @stable ICU 2.6
 378    */
 379   UCAL_YEAR_WOY,
 380
 381  /**
 382    * Field number
 383    * indicating the localized day of week.  This will be a value from 1
 384    * to 7 inclusive, with 1 being the localized first day of the week.
 385    * @stable ICU 2.6
 386    */
 387   UCAL_DOW_LOCAL,
 388
 389   /**
 390    * Year of this calendar system, encompassing all supra-year fields. For example,
 391    * in Gregorian/Julian calendars, positive Extended Year values indicate years AD,
 392    *  1 BC = 0 extended, 2 BC = -1 extended, and so on.
 393    * @stable ICU 2.8
 394    */
 395   UCAL_EXTENDED_YEAR,
 396
 397  /**
 398    * Field number
 399    * indicating the modified Julian day number.  This is different from
 400    * the conventional Julian day number in two regards.  First, it
 401    * demarcates days at local zone midnight, rather than noon GMT.
 402    * Second, it is a local number; that is, it depends on the local time
 403    * zone.  It can be thought of as a single number that encompasses all
 404    * the date-related fields.
 405    * @stable ICU 2.8
 406    */
 407   UCAL_JULIAN_DAY,
 408
 409   /**
 410    * Ranges from 0 to 23:59:59.999 (regardless of DST).  This field behaves <em>exactly</em>
 411    * like a composite of all time-related fields, not including the zone fields.  As such,
 412    * it also reflects discontinuities of those fields on DST transition days.  On a day
 413    * of DST onset, it will jump forward.  On a day of DST cessation, it will jump
 414    * backward.  This reflects the fact that it must be combined with the DST_OFFSET field
 415    * to obtain a unique local time value.
 416    * @stable ICU 2.8
 417    */
 418   UCAL_MILLISECONDS_IN_DAY,
 419
 420   /**
 421    * Whether or not the current month is a leap month (0 or 1). See the Chinese calendar for
 422    * an example of this.
 423    */
 424   UCAL_IS_LEAP_MONTH,
 425
 426   /**
 427    * Field count
 428    * @stable ICU 2.6
 429    */
 430   UCAL_FIELD_COUNT,
 431
 432  /**
 433    * Field number indicating the
 434    * day of the month. This is a synonym for <code>UCAL_DATE</code>.
 435    * The first day of the month has value 1.
 436    * @see #UCAL_DATE
 437    * Synonym for UCAL_DATE
 438    * @stable ICU 2.8
 439    **/
 440   UCAL_DAY_OF_MONTH=UCAL_DATE
 441 };
 442
 443 /** @stable ICU 2.0 */
 444 typedef enum UCalendarDateFields UCalendarDateFields;
 445     /**
 446      * Useful constant for days of week. Note: Calendar day-of-week is 1-based. Clients
 447      * who create locale resources for the field of first-day-of-week should be aware of
 448      * this. For instance, in US locale, first-day-of-week is set to 1, i.e., UCAL_SUNDAY.
 449      */
 450 /** Possible days of the week in a UCalendar
 451  * @stable ICU 2.0
 452  */
 453 enum UCalendarDaysOfWeek {
 454   /** Sunday */
 455   UCAL_SUNDAY = 1,
 456   /** Monday */
 457   UCAL_MONDAY,
 458   /** Tuesday */
 459   UCAL_TUESDAY,
 460   /** Wednesday */
 461   UCAL_WEDNESDAY,
 462   /** Thursday */
 463   UCAL_THURSDAY,
 464   /** Friday */
 465   UCAL_FRIDAY,
 466   /** Saturday */
 467   UCAL_SATURDAY
 468 };
 469
 470 /** @stable ICU 2.0 */
 471 typedef enum UCalendarDaysOfWeek UCalendarDaysOfWeek;
 472
 473 /** Possible months in a UCalendar. Note: Calendar month is 0-based.
 474  * @stable ICU 2.0
 475  */
 476 enum UCalendarMonths {
 477   /** January */
 478   UCAL_JANUARY,
 479   /** February */
 480   UCAL_FEBRUARY,
 481   /** March */
 482   UCAL_MARCH,
 483   /** April */
 484   UCAL_APRIL,
 485   /** May */
 486   UCAL_MAY,
 487   /** June */
 488   UCAL_JUNE,
 489   /** July */
 490   UCAL_JULY,
 491   /** August */
 492   UCAL_AUGUST,
 493   /** September */
 494   UCAL_SEPTEMBER,
 495   /** October */
 496   UCAL_OCTOBER,
 497   /** November */
 498   UCAL_NOVEMBER,
 499   /** December */
 500   UCAL_DECEMBER,
 501   /** Value of the <code>UCAL_MONTH</code> field indicating the
 502     * thirteenth month of the year. Although the Gregorian calendar
 503     * does not use this value, lunar calendars do.
 504     */
 505   UCAL_UNDECIMBER
 506 };
 507
 508 /** @stable ICU 2.0 */
 509 typedef enum UCalendarMonths UCalendarMonths;
 510
 511 /** Possible AM/PM values in a UCalendar
 512  * @stable ICU 2.0
 513  */
 514 enum UCalendarAMPMs {
 515     /** AM */
 516   UCAL_AM,
 517   /** PM */
 518   UCAL_PM
 519 };
 520
 521 /** @stable ICU 2.0 */
 522 typedef enum UCalendarAMPMs UCalendarAMPMs;
 523
 524 /**
 525  * System time zone type constants used by filtering zones
 526  * in ucal_openTimeZoneIDEnumeration.
 527  * @see ucal_openTimeZoneIDEnumeration
 528  * @stable ICU 4.8
 529  */
 530 enum USystemTimeZoneType {
 531     /**
 532      * Any system zones.
 533      * @stable ICU 4.8
 534      */
 535     UCAL_ZONE_TYPE_ANY,
 536     /**
 537      * Canonical system zones.
 538      * @stable ICU 4.8
 539      */
 540     UCAL_ZONE_TYPE_CANONICAL,
 541     /**
 542      * Canonical system zones associated with actual locations.
 543      * @stable ICU 4.8
 544      */
 545     UCAL_ZONE_TYPE_CANONICAL_LOCATION
 546 };
 547
 548 /** @stable ICU 4.8 */
 549 typedef enum USystemTimeZoneType USystemTimeZoneType;
 550
 551 /**
 552  * Create an enumeration over system time zone IDs with the given
 553  * filter conditions.
 554  * @param zoneType  The system time zone type.
 555  * @param region    The ISO 3166 two-letter country code or UN M.49
 556  *                  three-digit area code.  When NULL, no filtering
 557  *                  done by region.
 558  * @param rawOffset An offset from GMT in milliseconds, ignoring the
 559  *                  effect of daylight savings time, if any. When NULL,
 560  *                  no filtering done by zone offset.
 561  * @param ec        A pointer to an UErrorCode to receive any errors
 562  * @return  an enumeration object that the caller must dispose of
 563  *          using enum_close(), or NULL upon failure. In case of failure,
 564  *          *ec will indicate the error.
 565  * @stable ICU 4.8
 566  */
 567 U_DRAFT UEnumeration* U_EXPORT2
 568 ucal_openTimeZoneIDEnumeration(USystemTimeZoneType zoneType, const char* region,
 569                                 const int32_t* rawOffset, UErrorCode* ec);
 570
 571 /**
 572  * Create an enumeration over all time zones.
 573  *
 574  * @param ec input/output error code
 575  *
 576  * @return an enumeration object that the caller must dispose of using
 577  * uenum_close(), or NULL upon failure. In case of failure *ec will
 578  * indicate the error.
 579  *
 580  * @stable ICU 2.6
 581  */
 582 U_STABLE UEnumeration* U_EXPORT2
 583 ucal_openTimeZones(UErrorCode* ec);
 584
 585 /**
 586  * Create an enumeration over all time zones associated with the given
 587  * country. Some zones are affiliated with no country (e.g., "UTC");
 588  * these may also be retrieved, as a group.
 589  *
 590  * @param country the ISO 3166 two-letter country code, or NULL to
 591  * retrieve zones not affiliated with any country
 592  *
 593  * @param ec input/output error code
 594  *
 595  * @return an enumeration object that the caller must dispose of using
 596  * uenum_close(), or NULL upon failure. In case of failure *ec will
 597  * indicate the error.
 598  *
 599  * @stable ICU 2.6
 600  */
 601 U_STABLE UEnumeration* U_EXPORT2
 602 ucal_openCountryTimeZones(const char* country, UErrorCode* ec);
 603
 604 /**
 605  * Return the default time zone. The default is determined initially
 606  * by querying the host operating system. It may be changed with
 607  * ucal_setDefaultTimeZone() or with the C++ TimeZone API.
 608  *
 609  * @param result A buffer to receive the result, or NULL
 610  *
 611  * @param resultCapacity The capacity of the result buffer
 612  *
 613  * @param ec input/output error code
 614  *
 615  * @return The result string length, not including the terminating
 616  * null
 617  *
 618  * @stable ICU 2.6
 619  */
 620 U_STABLE int32_t U_EXPORT2
 621 ucal_getDefaultTimeZone(UChar* result, int32_t resultCapacity, UErrorCode* ec);
 622
 623 /**
 624  * Set the default time zone.
 625  *
 626  * @param zoneID null-terminated time zone ID
 627  *
 628  * @param ec input/output error code
 629  *
 630  * @stable ICU 2.6
 631  */
 632 U_STABLE void U_EXPORT2
 633 ucal_setDefaultTimeZone(const UChar* zoneID, UErrorCode* ec);
 634
 635 /**
 636  * Return the amount of time in milliseconds that the clock is
 637  * advanced during daylight savings time for the given time zone, or
 638  * zero if the time zone does not observe daylight savings time.
 639  *
 640  * @param zoneID null-terminated time zone ID
 641  *
 642  * @param ec input/output error code
 643  *
 644  * @return the number of milliseconds the time is advanced with
 645  * respect to standard time when the daylight savings rules are in
 646  * effect. This is always a non-negative number, most commonly either
 647  * 3,600,000 (one hour) or zero.
 648  *
 649  * @stable ICU 2.6
 650  */
 651 U_STABLE int32_t U_EXPORT2
 652 ucal_getDSTSavings(const UChar* zoneID, UErrorCode* ec);
 653
 654 /**
 655  * Get the current date and time.
 656  * The value returned is represented as milliseconds from the epoch.
 657  * @return The current date and time.
 658  * @stable ICU 2.0
 659  */
 660 U_STABLE UDate U_EXPORT2
 661 ucal_getNow(void);
 662
 663 /**
 664  * Open a UCalendar.
 665  * A UCalendar may be used to convert a millisecond value to a year,
 666  * month, and day.
 667  * <p>
 668  * Note: When unknown TimeZone ID is specified or if the TimeZone ID specified is "Etc/Unknown",
 669  * the UCalendar returned by the function is initialized with GMT zone with TimeZone ID
 670  * <code>UCAL_UNKNOWN_ZONE_ID</code> ("Etc/Unknown") without any errors/warnings.  If you want
 671  * to check if a TimeZone ID is valid prior to this function, use <code>ucal_getCanonicalTimeZoneID</code>.
 672  *
 673  * @param zoneID The desired TimeZone ID.  If 0, use the default time zone.
 674  * @param len The length of zoneID, or -1 if null-terminated.
 675  * @param locale The desired locale
 676  * @param type The type of UCalendar to open. This can be UCAL_GREGORIAN to open the Gregorian
 677  * calendar for the locale, or UCAL_DEFAULT to open the default calendar for the locale (the
 678  * default calendar may also be Gregorian). To open a specific non-Gregorian calendar for the
 679  * locale, use uloc_setKeywordValue to set the value of the calendar keyword for the locale
 680  * and then pass the locale to ucal_open with UCAL_DEFAULT as the type.
 681  * @param status A pointer to an UErrorCode to receive any errors
 682  * @return A pointer to a UCalendar, or 0 if an error occurred.
 683  * @see #UCAL_UNKNOWN_ZONE_ID
 684  * @stable ICU 2.0
 685  */
 686 U_STABLE UCalendar* U_EXPORT2
 687 ucal_open(const UChar*   zoneID,
 688           int32_t        len,
 689           const char*    locale,
 690           UCalendarType  type,
 691           UErrorCode*    status);
 692
 693 /**
 694  * Close a UCalendar.
 695  * Once closed, a UCalendar may no longer be used.
 696  * @param cal The UCalendar to close.
 697  * @stable ICU 2.0
 698  */
 699 U_STABLE void U_EXPORT2
 700 ucal_close(UCalendar *cal);
 701
 702 #if U_SHOW_CPLUSPLUS_API
 703
 704 U_NAMESPACE_BEGIN
 705
 706 /**
 707  * \class LocalUCalendarPointer
 708  * "Smart pointer" class, closes a UCalendar via ucal_close().
 709  * For most methods see the LocalPointerBase base class.
 710  *
 711  * @see LocalPointerBase
 712  * @see LocalPointer
 713  * @stable ICU 4.4
 714  */
 715 U_DEFINE_LOCAL_OPEN_POINTER(LocalUCalendarPointer, UCalendar, ucal_close);
 716
 717 U_NAMESPACE_END
 718
 719 #endif
 720
 721 /**
 722  * Open a copy of a UCalendar.
 723  * This function performs a deep copy.
 724  * @param cal The calendar to copy
 725  * @param status A pointer to an UErrorCode to receive any errors.
 726  * @return A pointer to a UCalendar identical to cal.
 727  * @stable ICU 4.0
 728  */
 729 U_STABLE UCalendar* U_EXPORT2
 730 ucal_clone(const UCalendar* cal,
 731            UErrorCode*      status);
 732
 733 /**
 734  * Set the TimeZone used by a UCalendar.
 735  * A UCalendar uses a timezone for converting from Greenwich time to local time.
 736  * @param cal The UCalendar to set.
 737  * @param zoneID The desired TimeZone ID.  If 0, use the default time zone.
 738  * @param len The length of zoneID, or -1 if null-terminated.
 739  * @param status A pointer to an UErrorCode to receive any errors.
 740  * @stable ICU 2.0
 741  */
 742 U_STABLE void U_EXPORT2
 743 ucal_setTimeZone(UCalendar*    cal,
 744                  const UChar*  zoneID,
 745                  int32_t       len,
 746                  UErrorCode*   status);
 747
 748 /**
 749  * Possible formats for a UCalendar's display name
 750  * @stable ICU 2.0
 751  */
 752 enum UCalendarDisplayNameType {
 753   /** Standard display name */
 754   UCAL_STANDARD,
 755   /** Short standard display name */
 756   UCAL_SHORT_STANDARD,
 757   /** Daylight savings display name */
 758   UCAL_DST,
 759   /** Short daylight savings display name */
 760   UCAL_SHORT_DST
 761 };
 762
 763 /** @stable ICU 2.0 */
 764 typedef enum UCalendarDisplayNameType UCalendarDisplayNameType;
 765
 766 /**
 767  * Get the display name for a UCalendar's TimeZone.
 768  * A display name is suitable for presentation to a user.
 769  * @param cal          The UCalendar to query.
 770  * @param type         The desired display name format; one of UCAL_STANDARD, UCAL_SHORT_STANDARD,
 771  *                     UCAL_DST, UCAL_SHORT_DST
 772  * @param locale       The desired locale for the display name.
 773  * @param result       A pointer to a buffer to receive the formatted number.
 774  * @param resultLength The maximum size of result.
 775  * @param status       A pointer to an UErrorCode to receive any errors
 776  * @return             The total buffer size needed; if greater than resultLength, the output was truncated.
 777  * @stable ICU 2.0
 778  */
 779 U_STABLE int32_t U_EXPORT2
 780 ucal_getTimeZoneDisplayName(const UCalendar*          cal,
 781                             UCalendarDisplayNameType  type,
 782                             const char*               locale,
 783                             UChar*                    result,
 784                             int32_t                   resultLength,
 785                             UErrorCode*               status);
 786
 787 /**
 788  * Determine if a UCalendar is currently in daylight savings time.
 789  * Daylight savings time is not used in all parts of the world.
 790  * @param cal The UCalendar to query.
 791  * @param status A pointer to an UErrorCode to receive any errors
 792  * @return TRUE if cal is currently in daylight savings time, FALSE otherwise
 793  * @stable ICU 2.0
 794  */
 795 U_STABLE UBool U_EXPORT2
 796 ucal_inDaylightTime(const UCalendar*  cal,
 797                     UErrorCode*       status );
 798
 799 /**
 800  * Sets the GregorianCalendar change date. This is the point when the switch from
 801  * Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October
 802  * 15, 1582. Previous to this time and date will be Julian dates.
 803  *
 804  * This function works only for Gregorian calendars. If the UCalendar is not
 805  * an instance of a Gregorian calendar, then a U_UNSUPPORTED_ERROR
 806  * error code is set.
 807  *
 808  * @param cal        The calendar object.
 809  * @param date       The given Gregorian cutover date.
 810  * @param pErrorCode Pointer to a standard ICU error code. Its input value must
 811  *                   pass the U_SUCCESS() test, or else the function returns
 812  *                   immediately. Check for U_FAILURE() on output or use with
 813  *                   function chaining. (See User Guide for details.)
 814  *
 815  * @see GregorianCalendar::setGregorianChange
 816  * @see ucal_getGregorianChange
 817  * @stable ICU 3.6
 818  */
 819 U_STABLE void U_EXPORT2
 820 ucal_setGregorianChange(UCalendar *cal, UDate date, UErrorCode *pErrorCode);
 821
 822 /**
 823  * Gets the Gregorian Calendar change date. This is the point when the switch from
 824  * Julian dates to Gregorian dates occurred. Default is 00:00:00 local time, October
 825  * 15, 1582. Previous to this time and date will be Julian dates.
 826  *
 827  * This function works only for Gregorian calendars. If the UCalendar is not
 828  * an instance of a Gregorian calendar, then a U_UNSUPPORTED_ERROR
 829  * error code is set.
 830  *
 831  * @param cal        The calendar object.
 832  * @param pErrorCode Pointer to a standard ICU error code. Its input value must
 833  *                   pass the U_SUCCESS() test, or else the function returns
 834  *                   immediately. Check for U_FAILURE() on output or use with
 835  *                   function chaining. (See User Guide for details.)
 836  * @return   The Gregorian cutover time for this calendar.
 837  *
 838  * @see GregorianCalendar::getGregorianChange
 839  * @see ucal_setGregorianChange
 840  * @stable ICU 3.6
 841  */
 842 U_STABLE UDate U_EXPORT2
 843 ucal_getGregorianChange(const UCalendar *cal, UErrorCode *pErrorCode);
 844
 845 /**
 846  * Types of UCalendar attributes
 847  * @stable ICU 2.0
 848  */
 849 enum UCalendarAttribute {
 850   /**
 851    * Lenient parsing
 852    * @stable ICU 2.0
 853    */
 854   UCAL_LENIENT,
 855   /**
 856    * First day of week
 857    * @stable ICU 2.0
 858    */
 859   UCAL_FIRST_DAY_OF_WEEK,
 860   /**
 861    * Minimum number of days in first week
 862    * @stable ICU 2.0
 863    */
 864   UCAL_MINIMAL_DAYS_IN_FIRST_WEEK
 865 #ifndef U_HIDE_DRAFT_API
 866   ,
 867   /**
 868    * The behavior for handling wall time repeating multiple times
 869    * at negative time zone offset transitions
 870    * @draft ICU 49
 871    */
 872   UCAL_REPEATED_WALL_TIME,
 873   /**
 874    * The behavior for handling skipped wall time at positive time
 875    * zone offset transitions.
 876    * @draft ICU 49
 877    */
 878   UCAL_SKIPPED_WALL_TIME
 879 #endif  /* U_HIDE_DRAFT_API */
 880 };
 881
 882 /** @stable ICU 2.0 */
 883 typedef enum UCalendarAttribute UCalendarAttribute;
 884
 885 /**
 886  * Options for handling ambiguous wall time at time zone
 887  * offset transitions.
 888  * @draft ICU 49
 889  */
 890 enum UCalendarWallTimeOption {
 891     /**
 892      * An ambiguous wall time to be interpreted as the latest.
 893      * This option is valid for UCAL_REPEATED_WALL_TIME and
 894      * UCAL_SKIPPED_WALL_TIME.
 895      * @draft ICU 49
 896      */
 897     UCAL_WALLTIME_LAST
 898 #ifndef U_HIDE_DRAFT_API
 899     ,
 900     /**
 901      * An ambiguous wall time to be interpreted as the earliest.
 902      * This option is valid for UCAL_REPEATED_WALL_TIME and
 903      * UCAL_SKIPPED_WALL_TIME.
 904      * @draft ICU 49
 905      */
 906     UCAL_WALLTIME_FIRST,
 907     /**
 908      * An ambiguous wall time to be interpreted as the next valid
 909      * wall time. This option is valid for UCAL_SKIPPED_WALL_TIME.
 910      * @draft ICU 49
 911      */
 912     UCAL_WALLTIME_NEXT_VALID
 913 #endif  /* U_HIDE_DRAFT_API */
 914 };
 915 /** @draft ICU 49 */
 916 typedef enum UCalendarWallTimeOption UCalendarWallTimeOption;
 917
 918 /**
 919  * Get a numeric attribute associated with a UCalendar.
 920  * Numeric attributes include the first day of the week, or the minimal numbers
 921  * of days in the first week of the month.
 922  * @param cal The UCalendar to query.
 923  * @param attr The desired attribute; one of UCAL_LENIENT, UCAL_FIRST_DAY_OF_WEEK,
 924  * UCAL_MINIMAL_DAYS_IN_FIRST_WEEK, UCAL_REPEATED_WALL_TIME or UCAL_SKIPPED_WALL_TIME
 925  * @return The value of attr.
 926  * @see ucal_setAttribute
 927  * @stable ICU 2.0
 928  */
 929 U_STABLE int32_t U_EXPORT2
 930 ucal_getAttribute(const UCalendar*    cal,
 931                   UCalendarAttribute  attr);
 932
 933 /**
 934  * Set a numeric attribute associated with a UCalendar.
 935  * Numeric attributes include the first day of the week, or the minimal numbers
 936  * of days in the first week of the month.
 937  * @param cal The UCalendar to set.
 938  * @param attr The desired attribute; one of UCAL_LENIENT, UCAL_FIRST_DAY_OF_WEEK,
 939  * UCAL_MINIMAL_DAYS_IN_FIRST_WEEK, UCAL_REPEATED_WALL_TIME or UCAL_SKIPPED_WALL_TIME
 940  * @param newValue The new value of attr.
 941  * @see ucal_getAttribute
 942  * @stable ICU 2.0
 943  */
 944 U_STABLE void U_EXPORT2
 945 ucal_setAttribute(UCalendar*          cal,
 946                   UCalendarAttribute  attr,
 947                   int32_t             newValue);
 948
 949 /**
 950  * Get a locale for which calendars are available.
 951  * A UCalendar in a locale returned by this function will contain the correct
 952  * day and month names for the locale.
 953  * @param localeIndex The index of the desired locale.
 954  * @return A locale for which calendars are available, or 0 if none.
 955  * @see ucal_countAvailable
 956  * @stable ICU 2.0
 957  */
 958 U_STABLE const char* U_EXPORT2
 959 ucal_getAvailable(int32_t localeIndex);
 960
 961 /**
 962  * Determine how many locales have calendars available.
 963  * This function is most useful as determining the loop ending condition for
 964  * calls to \ref ucal_getAvailable.
 965  * @return The number of locales for which calendars are available.
 966  * @see ucal_getAvailable
 967  * @stable ICU 2.0
 968  */
 969 U_STABLE int32_t U_EXPORT2
 970 ucal_countAvailable(void);
 971
 972 /**
 973  * Get a UCalendar's current time in millis.
 974  * The time is represented as milliseconds from the epoch.
 975  * @param cal The UCalendar to query.
 976  * @param status A pointer to an UErrorCode to receive any errors
 977  * @return The calendar's current time in millis.
 978  * @see ucal_setMillis
 979  * @see ucal_setDate
 980  * @see ucal_setDateTime
 981  * @stable ICU 2.0
 982  */
 983 U_STABLE UDate U_EXPORT2
 984 ucal_getMillis(const UCalendar*  cal,
 985                UErrorCode*       status);
 986
 987 /**
 988  * Set a UCalendar's current time in millis.
 989  * The time is represented as milliseconds from the epoch.
 990  * @param cal The UCalendar to set.
 991  * @param dateTime The desired date and time.
 992  * @param status A pointer to an UErrorCode to receive any errors
 993  * @see ucal_getMillis
 994  * @see ucal_setDate
 995  * @see ucal_setDateTime
 996  * @stable ICU 2.0
 997  */
 998 U_STABLE void U_EXPORT2
 999 ucal_setMillis(UCalendar*   cal,
1000                UDate        dateTime,
1001                UErrorCode*  status );
1002
1003 /**
1004  * Set a UCalendar's current date.
1005  * The date is represented as a series of 32-bit integers.
1006  * @param cal The UCalendar to set.
1007  * @param year The desired year.
1008  * @param month The desired month; one of UCAL_JANUARY, UCAL_FEBRUARY, UCAL_MARCH, UCAL_APRIL, UCAL_MAY,
1009  * UCAL_JUNE, UCAL_JULY, UCAL_AUGUST, UCAL_SEPTEMBER, UCAL_OCTOBER, UCAL_NOVEMBER, UCAL_DECEMBER, UCAL_UNDECIMBER
1010  * @param date The desired day of the month.
1011  * @param status A pointer to an UErrorCode to receive any errors
1012  * @see ucal_getMillis
1013  * @see ucal_setMillis
1014  * @see ucal_setDateTime
1015  * @stable ICU 2.0
1016  */
1017 U_STABLE void U_EXPORT2
1018 ucal_setDate(UCalendar*   cal,
1019              int32_t      year,
1020              int32_t      month,
1021              int32_t      date,
1022              UErrorCode*  status);
1023
1024 /**
1025  * Set a UCalendar's current date.
1026  * The date is represented as a series of 32-bit integers.
1027  * @param cal The UCalendar to set.
1028  * @param year The desired year.
1029  * @param month The desired month; one of UCAL_JANUARY, UCAL_FEBRUARY, UCAL_MARCH, UCAL_APRIL, UCAL_MAY,
1030  * UCAL_JUNE, UCAL_JULY, UCAL_AUGUST, UCAL_SEPTEMBER, UCAL_OCTOBER, UCAL_NOVEMBER, UCAL_DECEMBER, UCAL_UNDECIMBER
1031  * @param date The desired day of the month.
1032  * @param hour The desired hour of day.
1033  * @param minute The desired minute.
1034  * @param second The desirec second.
1035  * @param status A pointer to an UErrorCode to receive any errors
1036  * @see ucal_getMillis
1037  * @see ucal_setMillis
1038  * @see ucal_setDate
1039  * @stable ICU 2.0
1040  */
1041 U_STABLE void U_EXPORT2
1042 ucal_setDateTime(UCalendar*   cal,
1043                  int32_t      year,
1044                  int32_t      month,
1045                  int32_t      date,
1046                  int32_t      hour,
1047                  int32_t      minute,
1048                  int32_t      second,
1049                  UErrorCode*  status);
1050
1051 /**
1052  * Returns TRUE if two UCalendars are equivalent.  Equivalent
1053  * UCalendars will behave identically, but they may be set to
1054  * different times.
1055  * @param cal1 The first of the UCalendars to compare.
1056  * @param cal2 The second of the UCalendars to compare.
1057  * @return TRUE if cal1 and cal2 are equivalent, FALSE otherwise.
1058  * @stable ICU 2.0
1059  */
1060 U_STABLE UBool U_EXPORT2
1061 ucal_equivalentTo(const UCalendar*  cal1,
1062                   const UCalendar*  cal2);
1063
1064 /**
1065  * Add a specified signed amount to a particular field in a UCalendar.
1066  * This can modify more significant fields in the calendar.
1067  * @param cal The UCalendar to which to add.
1068  * @param field The field to which to add the signed value; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1069  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1070  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1071  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1072  * @param amount The signed amount to add to field. If the amount causes the value
1073  * to exceed to maximum or minimum values for that field, other fields are modified
1074  * to preserve the magnitude of the change.
1075  * @param status A pointer to an UErrorCode to receive any errors
1076  * @see ucal_roll
1077  * @stable ICU 2.0
1078  */
1079 U_STABLE void U_EXPORT2
1080 ucal_add(UCalendar*           cal,
1081          UCalendarDateFields  field,
1082          int32_t              amount,
1083          UErrorCode*          status);
1084
1085 /**
1086  * Add a specified signed amount to a particular field in a UCalendar.
1087  * This will not modify more significant fields in the calendar.
1088  * @param cal The UCalendar to which to add.
1089  * @param field The field to which to add the signed value; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1090  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1091  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1092  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1093  * @param amount The signed amount to add to field. If the amount causes the value
1094  * to exceed to maximum or minimum values for that field, the field is pinned to a permissible
1095  * value.
1096  * @param status A pointer to an UErrorCode to receive any errors
1097  * @see ucal_add
1098  * @stable ICU 2.0
1099  */
1100 U_STABLE void U_EXPORT2
1101 ucal_roll(UCalendar*           cal,
1102           UCalendarDateFields  field,
1103           int32_t              amount,
1104           UErrorCode*          status);
1105
1106 /**
1107  * Get the current value of a field from a UCalendar.
1108  * All fields are represented as 32-bit integers.
1109  * @param cal The UCalendar to query.
1110  * @param field The desired field; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1111  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1112  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1113  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1114  * @param status A pointer to an UErrorCode to receive any errors
1115  * @return The value of the desired field.
1116  * @see ucal_set
1117  * @see ucal_isSet
1118  * @see ucal_clearField
1119  * @see ucal_clear
1120  * @stable ICU 2.0
1121  */
1122 U_STABLE int32_t U_EXPORT2
1123 ucal_get(const UCalendar*     cal,
1124          UCalendarDateFields  field,
1125          UErrorCode*          status );
1126
1127 /**
1128  * Set the value of a field in a UCalendar.
1129  * All fields are represented as 32-bit integers.
1130  * @param cal The UCalendar to set.
1131  * @param field The field to set; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1132  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1133  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1134  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1135  * @param value The desired value of field.
1136  * @see ucal_get
1137  * @see ucal_isSet
1138  * @see ucal_clearField
1139  * @see ucal_clear
1140  * @stable ICU 2.0
1141  */
1142 U_STABLE void U_EXPORT2
1143 ucal_set(UCalendar*           cal,
1144          UCalendarDateFields  field,
1145          int32_t              value);
1146
1147 /**
1148  * Determine if a field in a UCalendar is set.
1149  * All fields are represented as 32-bit integers.
1150  * @param cal The UCalendar to query.
1151  * @param field The desired field; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1152  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1153  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1154  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1155  * @return TRUE if field is set, FALSE otherwise.
1156  * @see ucal_get
1157  * @see ucal_set
1158  * @see ucal_clearField
1159  * @see ucal_clear
1160  * @stable ICU 2.0
1161  */
1162 U_STABLE UBool U_EXPORT2
1163 ucal_isSet(const UCalendar*     cal,
1164            UCalendarDateFields  field);
1165
1166 /**
1167  * Clear a field in a UCalendar.
1168  * All fields are represented as 32-bit integers.
1169  * @param cal The UCalendar containing the field to clear.
1170  * @param field The field to clear; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1171  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1172  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1173  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1174  * @see ucal_get
1175  * @see ucal_set
1176  * @see ucal_isSet
1177  * @see ucal_clear
1178  * @stable ICU 2.0
1179  */
1180 U_STABLE void U_EXPORT2
1181 ucal_clearField(UCalendar*           cal,
1182                 UCalendarDateFields  field);
1183
1184 /**
1185  * Clear all fields in a UCalendar.
1186  * All fields are represented as 32-bit integers.
1187  * @param calendar The UCalendar to clear.
1188  * @see ucal_get
1189  * @see ucal_set
1190  * @see ucal_isSet
1191  * @see ucal_clearField
1192  * @stable ICU 2.0
1193  */
1194 U_STABLE void U_EXPORT2
1195 ucal_clear(UCalendar* calendar);
1196
1197 /**
1198  * Possible limit values for a UCalendar
1199  * @stable ICU 2.0
1200  */
1201 enum UCalendarLimitType {
1202   /** Minimum value */
1203   UCAL_MINIMUM,
1204   /** Maximum value */
1205   UCAL_MAXIMUM,
1206   /** Greatest minimum value */
1207   UCAL_GREATEST_MINIMUM,
1208   /** Leaest maximum value */
1209   UCAL_LEAST_MAXIMUM,
1210   /** Actual minimum value */
1211   UCAL_ACTUAL_MINIMUM,
1212   /** Actual maximum value */
1213   UCAL_ACTUAL_MAXIMUM
1214 };
1215
1216 /** @stable ICU 2.0 */
1217 typedef enum UCalendarLimitType UCalendarLimitType;
1218
1219 /**
1220  * Determine a limit for a field in a UCalendar.
1221  * A limit is a maximum or minimum value for a field.
1222  * @param cal The UCalendar to query.
1223  * @param field The desired field; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1224  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1225  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1226  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1227  * @param type The desired critical point; one of UCAL_MINIMUM, UCAL_MAXIMUM, UCAL_GREATEST_MINIMUM,
1228  * UCAL_LEAST_MAXIMUM, UCAL_ACTUAL_MINIMUM, UCAL_ACTUAL_MAXIMUM
1229  * @param status A pointer to an UErrorCode to receive any errors.
1230  * @return The requested value.
1231  * @stable ICU 2.0
1232  */
1233 U_STABLE int32_t U_EXPORT2
1234 ucal_getLimit(const UCalendar*     cal,
1235               UCalendarDateFields  field,
1236               UCalendarLimitType   type,
1237               UErrorCode*          status);
1238
1239 /** Get the locale for this calendar object. You can choose between valid and actual locale.
1240  *  @param cal The calendar object
1241  *  @param type type of the locale we're looking for (valid or actual)
1242  *  @param status error code for the operation
1243  *  @return the locale name
1244  *  @stable ICU 2.8
1245  */
1246 U_STABLE const char * U_EXPORT2
1247 ucal_getLocaleByType(const UCalendar *cal, ULocDataLocaleType type, UErrorCode* status);
1248
1249 /**
1250  * Returns the timezone data version currently used by ICU.
1251  * @param status error code for the operation
1252  * @return the version string, such as "2007f"
1253  * @stable ICU 3.8
1254  */
1255 U_STABLE const char * U_EXPORT2
1256 ucal_getTZDataVersion(UErrorCode* status);
1257
1258 /**
1259  * Returns the canonical system timezone ID or the normalized
1260  * custom time zone ID for the given time zone ID.
1261  * @param id        The input timezone ID to be canonicalized.
1262  * @param len       The length of id, or -1 if null-terminated.
1263  * @param result    The buffer receives the canonical system timezone ID
1264  *                  or the custom timezone ID in normalized format.
1265  * @param resultCapacity    The capacity of the result buffer.
1266  * @param isSystemID        Receives if the given ID is a known system
1267      *                      timezone ID.
1268  * @param status    Recevies the status.  When the given timezone ID
1269  *                  is neither a known system time zone ID nor a
1270  *                  valid custom timezone ID, U_ILLEGAL_ARGUMENT_ERROR
1271  *                  is set.
1272  * @return          The result string length, not including the terminating
1273  *                  null.
1274  * @stable ICU 4.0
1275  */
1276 U_STABLE int32_t U_EXPORT2
1277 ucal_getCanonicalTimeZoneID(const UChar* id, int32_t len,
1278                             UChar* result, int32_t resultCapacity, UBool *isSystemID, UErrorCode* status);
1279 /**
1280  * Get the resource keyword value string designating the calendar type for the UCalendar.
1281  * @param cal The UCalendar to query.
1282  * @param status The error code for the operation.
1283  * @return The resource keyword value string.
1284  * @stable ICU 4.2
1285  */
1286 U_STABLE const char * U_EXPORT2
1287 ucal_getType(const UCalendar *cal, UErrorCode* status);
1288
1289 /**
1290  * Given a key and a locale, returns an array of string values in a preferred
1291  * order that would make a difference. These are all and only those values where
1292  * the open (creation) of the service with the locale formed from the input locale
1293  * plus input keyword and that value has different behavior than creation with the
1294  * input locale alone.
1295  * @param key           one of the keys supported by this service.  For now, only
1296  *                      "calendar" is supported.
1297  * @param locale        the locale
1298  * @param commonlyUsed  if set to true it will return only commonly used values
1299  *                      with the given locale in preferred order.  Otherwise,
1300  *                      it will return all the available values for the locale.
1301  * @param status error status
1302  * @return a string enumeration over keyword values for the given key and the locale.
1303  * @stable ICU 4.2
1304  */
1305 U_STABLE UEnumeration* U_EXPORT2
1306 ucal_getKeywordValuesForLocale(const char* key,
1307                                const char* locale,
1308                                UBool commonlyUsed,
1309                                UErrorCode* status);
1310
1311
1312 /** Weekday types, as returned by ucal_getDayOfWeekType().
1313  * @stable ICU 4.4
1314  */
1315 enum UCalendarWeekdayType {
1316   /**
1317    * Designates a full weekday (no part of the day is included in the weekend).
1318    * @stable ICU 4.4
1319    */
1320   UCAL_WEEKDAY,
1321   /**
1322    * Designates a full weekend day (the entire day is included in the weekend).
1323    * @stable ICU 4.4
1324    */
1325   UCAL_WEEKEND,
1326   /**
1327    * Designates a day that starts as a weekday and transitions to the weekend.
1328    * Call ucal_getWeekendTransition() to get the time of transition.
1329    * @stable ICU 4.4
1330    */
1331   UCAL_WEEKEND_ONSET,
1332   /**
1333    * Designates a day that starts as the weekend and transitions to a weekday.
1334    * Call ucal_getWeekendTransition() to get the time of transition.
1335    * @stable ICU 4.4
1336    */
1337   UCAL_WEEKEND_CEASE
1338 };
1339
1340 /** @stable ICU 4.4 */
1341 typedef enum UCalendarWeekdayType UCalendarWeekdayType;
1342
1343 /**
1344  * Returns whether the given day of the week is a weekday, a
1345  * weekend day, or a day that transitions from one to the other,
1346  * in this calendar system. If a transition occurs at midnight,
1347  * then the days before and after the transition will have the
1348  * type UCAL_WEEKDAY or UCAL_WEEKEND. If a transition occurs at a time
1349  * other than midnight, then the day of the transition will have
1350  * the type UCAL_WEEKEND_ONSET or UCAL_WEEKEND_CEASE. In this case, the
1351  * method getWeekendTransition() will return the point of
1352  * transition.
1353  * @param cal The UCalendar to query.
1354  * @param dayOfWeek The day of the week whose type is desired (UCAL_SUNDAY..UCAL_SATURDAY).
1355  * @param status The error code for the operation.
1356  * @return The UCalendarWeekdayType for the day of the week.
1357  * @stable ICU 4.4
1358  */
1359 U_STABLE UCalendarWeekdayType U_EXPORT2
1360 ucal_getDayOfWeekType(const UCalendar *cal, UCalendarDaysOfWeek dayOfWeek, UErrorCode* status);
1361
1362 /**
1363  * Returns the time during the day at which the weekend begins or ends in
1364  * this calendar system.  If ucal_getDayOfWeekType() rerturns UCAL_WEEKEND_ONSET
1365  * for the specified dayOfWeek, return the time at which the weekend begins.
1366  * If ucal_getDayOfWeekType() returns UCAL_WEEKEND_CEASE for the specified dayOfWeek,
1367  * return the time at which the weekend ends. If ucal_getDayOfWeekType() returns
1368  * some other UCalendarWeekdayType for the specified dayOfWeek, is it an error condition
1369  * (U_ILLEGAL_ARGUMENT_ERROR).
1370  * @param cal The UCalendar to query.
1371  * @param dayOfWeek The day of the week for which the weekend transition time is
1372  * desired (UCAL_SUNDAY..UCAL_SATURDAY).
1373  * @param status The error code for the operation.
1374  * @return The milliseconds after midnight at which the weekend begins or ends.
1375  * @stable ICU 4.4
1376  */
1377 U_STABLE int32_t U_EXPORT2
1378 ucal_getWeekendTransition(const UCalendar *cal, UCalendarDaysOfWeek dayOfWeek, UErrorCode *status);
1379
1380 /**
1381  * Returns TRUE if the given UDate is in the weekend in
1382  * this calendar system.
1383  * @param cal The UCalendar to query.
1384  * @param date The UDate in question.
1385  * @param status The error code for the operation.
1386  * @return TRUE if the given UDate is in the weekend in
1387  * this calendar system, FALSE otherwise.
1388  * @stable ICU 4.4
1389  */
1390 U_STABLE UBool U_EXPORT2
1391 ucal_isWeekend(const UCalendar *cal, UDate date, UErrorCode *status);
1392
1393 /**
1394  * Return the difference between the target time and the time this calendar object is currently set to.
1395  * If the target time is after the current calendar setting, the the returned value will be positive.
1396  * The field parameter specifies the units of the return value. For example, if field is UCAL_MONTH
1397  * and ucal_getFieldDifference returns 3, then the target time is 3 to less than 4 months after the
1398  * current calendar setting.
1399  *
1400  * As a side effect of this call, this calendar is advanced toward target by the given amount. That is,
1401  * calling this function has the side effect of calling ucal_add on this calendar with the specified
1402  * field and an amount equal to the return value from this function.
1403  *
1404  * A typical way of using this function is to call it first with the largest field of interest, then
1405  * with progressively smaller fields.
1406  *
1407  * @param cal The UCalendar to compare and update.
1408  * @param target The target date to compare to the current calendar setting.
1409  * @param field The field to compare; one of UCAL_ERA, UCAL_YEAR, UCAL_MONTH,
1410  * UCAL_WEEK_OF_YEAR, UCAL_WEEK_OF_MONTH, UCAL_DATE, UCAL_DAY_OF_YEAR, UCAL_DAY_OF_WEEK,
1411  * UCAL_DAY_OF_WEEK_IN_MONTH, UCAL_AM_PM, UCAL_HOUR, UCAL_HOUR_OF_DAY, UCAL_MINUTE, UCAL_SECOND,
1412  * UCAL_MILLISECOND, UCAL_ZONE_OFFSET, UCAL_DST_OFFSET.
1413  * @param status A pointer to an UErrorCode to receive any errors
1414  * @return The date difference for the specified field.
1415  * @stable ICU 4.8
1416  */
1417 U_DRAFT int32_t U_EXPORT2
1418 ucal_getFieldDifference(UCalendar* cal,
1419                         UDate target,
1420                         UCalendarDateFields field,
1421                         UErrorCode* status);
1422
1423 #endif /* #if !UCONFIG_NO_FORMATTING */
1424
1425 #endif