icuSources/i18n/vzone.h

   1 // © 2016 and later: Unicode, Inc. and others.
   2 // License & terms of use: http://www.unicode.org/copyright.html
   3 /*
   4 *******************************************************************************
   5 * Copyright (C) 2009-2016, International Business Machines Corporation and
   6 * others. All Rights Reserved.
   7 *******************************************************************************
   8 */
   9
  10 /**
  11 * \file
  12 * \brief C API: RFC2445 VTIMEZONE support
  13 *
  14 * <p>This is a C wrapper around the C++ VTimeZone class.</p>
  15 */
  16
  17 #ifndef __VZONE_H
  18 #define __VZONE_H
  19
  20 #include "unicode/utypes.h"
  21
  22 #if !UCONFIG_NO_FORMATTING
  23
  24 #include "unicode/uobject.h"
  25 #include "ztrans.h"
  26
  27 #ifndef UCNV_H
  28 struct VZone;
  29 /**
  30  * A UnicodeSet.  Use the vzone_* API to manipulate.  Create with
  31  * vzone_open*, and destroy with vzone_close.
  32  */
  33 typedef struct VZone VZone;
  34 #endif
  35
  36 /*********************************************************************
  37  * VZone API
  38  *********************************************************************/
  39
  40 /**
  41  * Creates a vzone from the given time zone ID.
  42  * @param ID The time zone ID, such as America/New_York
  43  * @param idLength, length of the ID parameter
  44  * @return A vzone object initialized by the time zone ID,
  45  * or NULL when the ID is unknown.
  46  */
  47 U_CAPI VZone* U_EXPORT2
  48 vzone_openID(const UChar* ID, int32_t idLength);
  49
  50 /**
  51  * Create a vzone instance by RFC2445 VTIMEZONE data
  52  * @param vtzdata The string including VTIMEZONE data block
  53  * @param vtzdataLength, length of the vtzdata
  54  * @param status Output param to filled in with a success or an error.
  55  * @return A vzone initialized by the VTIMEZONE data or
  56  * NULL if failed to load the rule from the VTIMEZONE data.
  57  */
  58 U_CAPI VZone* U_EXPORT2
  59 vzone_openData(const UChar* vtzdata, int32_t vtzdataLength, UErrorCode& status);
  60
  61 /**
  62  * Disposes of the storage used by a VZone object.  This function should
  63  * be called exactly once for objects returned by vzone_open*.
  64  * @param set the object to dispose of
  65  */
  66 U_CAPI void U_EXPORT2
  67 vzone_close(VZone* zone);
  68
  69 /**
  70  * Returns a copy of this object.
  71  * @param zone the original vzone
  72  * @return the newly allocated copy of the vzone
  73  */
  74 U_CAPI VZone* U_EXPORT2
  75 vzone_clone(const VZone *zone);
  76
  77 /**
  78  * Returns true if zone1 is identical to zone2
  79  * and vis versa.
  80  * @param zone1 to be checked for containment
  81  * @param zone2 to be checked for containment
  82  * @return true if the test condition is met
  83  */
  84 U_CAPI UBool U_EXPORT2
  85 vzone_equals(const VZone* zone1, const VZone* zone2);
  86
  87 /**
  88  * Gets the RFC2445 TZURL property value.  When a vzone instance was
  89  * created from VTIMEZONE data, the initial value is set by the TZURL
  90  * property value in the data.  Otherwise, the initial value is not set.
  91  * @param zone, the vzone to use
  92  * @param url Receives the RFC2445 TZURL property value.
  93  * @param urlLength, length of the url
  94  * @return TRUE if TZURL attribute is available and value is set.
  95  */
  96 U_CAPI UBool U_EXPORT2
  97 vzone_getTZURL(VZone* zone, UChar* & url, int32_t & urlLength);
  98
  99 /**
 100  * Sets the RFC2445 TZURL property value.
 101  * @param zone, the vzone to use
 102  * @param url The TZURL property value.
 103  * @param urlLength, length of the url
 104  */
 105 U_CAPI void U_EXPORT2
 106 vzone_setTZURL(VZone* zone, UChar* url, int32_t urlLength);
 107
 108 /**
 109  * Gets the RFC2445 LAST-MODIFIED property value.  When a vzone instance
 110  * was created from VTIMEZONE data, the initial value is set by the
 111  * LAST-MODIFIED property value in the data.  Otherwise, the initial value
 112  * is not set.
 113  * @param zone, the vzone to use
 114  * @param lastModified Receives the last modified date.
 115  * @return TRUE if lastModified attribute is available and value is set.
 116  */
 117 U_CAPI UBool U_EXPORT2
 118 vzone_getLastModified(VZone* zone, UDate& lastModified);
 119
 120 /**
 121  * Sets the RFC2445 LAST-MODIFIED property value.
 122  * @param zone, the vzone to use
 123  * @param lastModified The LAST-MODIFIED date.
 124  */
 125 U_CAPI void U_EXPORT2
 126 vzone_setLastModified(VZone* zone, UDate lastModified);
 127
 128 /**
 129  * Writes RFC2445 VTIMEZONE data for this time zone
 130  * @param zone, the vzone to use
 131  * @param result Output param to filled in with the VTIMEZONE data.
 132  * @param resultLength, length of the result output
 133  * @param status Output param to filled in with a success or an error.
 134  */
 135 U_CAPI void U_EXPORT2
 136 vzone_write(VZone* zone, UChar* & result, int32_t & resultLength, UErrorCode& status);
 137
 138 /**
 139  * Writes RFC2445 VTIMEZONE data for this time zone applicalbe
 140  * for dates after the specified start time.
 141  * @param zone, the vzone to use
 142  * @param start The start date.
 143  * @param result Output param to filled in with the VTIMEZONE data.
 144  * @param resultLength, length of the result output
 145  * @param status Output param to filled in with a success or an error.
 146  */
 147 U_CAPI void U_EXPORT2
 148 vzone_writeFromStart(VZone* zone, UDate start, UChar* & result, int32_t & resultLength, UErrorCode& status);
 149
 150 /**
 151  * Writes RFC2445 VTIMEZONE data applicalbe for the specified date.
 152  * Some common iCalendar implementations can only handle a single time
 153  * zone property or a pair of standard and daylight time properties using
 154  * BYDAY rule with day of week (such as BYDAY=1SUN).  This method produce
 155  * the VTIMEZONE data which can be handled these implementations.  The rules
 156  * produced by this method can be used only for calculating time zone offset
 157  * around the specified date.
 158  * @param zone, the vzone to use
 159  * @param time The date used for rule extraction.
 160  * @param result Output param to filled in with the VTIMEZONE data.
 161  * @param status Output param to filled in with a success or an error.
 162  */
 163 U_CAPI void U_EXPORT2
 164 vzone_writeSimple(VZone* zone, UDate time, UChar* & result, int32_t & resultLength, UErrorCode& status);
 165
 166 /**
 167  * Returns the TimeZone's adjusted GMT offset (i.e., the number of milliseconds to add
 168  * to GMT to get local time in this time zone, taking daylight savings time into
 169  * account) as of a particular reference date.  The reference date is used to determine
 170  * whether daylight savings time is in effect and needs to be figured into the offset
 171  * that is returned (in other words, what is the adjusted GMT offset in this time zone
 172  * at this particular date and time?).  For the time zones produced by createTimeZone(),
 173  * the reference data is specified according to the Gregorian calendar, and the date
 174  * and time fields are local standard time.
 175  *
 176  * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
 177  * which returns both the raw and the DST offset for a given time. This method
 178  * is retained only for backward compatibility.
 179  *
 180  * @param zone, the vzone to use
 181  * @param era        The reference date's era
 182  * @param year       The reference date's year
 183  * @param month      The reference date's month (0-based; 0 is January)
 184  * @param day        The reference date's day-in-month (1-based)
 185  * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
 186  * @param millis     The reference date's milliseconds in day, local standard time
 187  * @param status     Output param to filled in with a success or an error.
 188  * @return           The offset in milliseconds to add to GMT to get local time.
 189  */
 190 U_CAPI int32_t U_EXPORT2
 191 vzone_getOffset(VZone* zone, uint8_t era, int32_t year, int32_t month, int32_t day,
 192                 uint8_t dayOfWeek, int32_t millis, UErrorCode& status);
 193
 194 /**
 195  * Gets the time zone offset, for current date, modified in case of
 196  * daylight savings. This is the offset to add *to* UTC to get local time.
 197  *
 198  * <p>Note: Don't call this method. Instead, call the getOffset(UDate...) overload,
 199  * which returns both the raw and the DST offset for a given time. This method
 200  * is retained only for backward compatibility.
 201  *
 202  * @param zone, the vzone to use
 203  * @param era        The reference date's era
 204  * @param year       The reference date's year
 205  * @param month      The reference date's month (0-based; 0 is January)
 206  * @param day        The reference date's day-in-month (1-based)
 207  * @param dayOfWeek  The reference date's day-of-week (1-based; 1 is Sunday)
 208  * @param millis     The reference date's milliseconds in day, local standard time
 209  * @param monthLength The length of the given month in days.
 210  * @param status     Output param to filled in with a success or an error.
 211  * @return           The offset in milliseconds to add to GMT to get local time.
 212  */
 213 U_CAPI int32_t U_EXPORT2
 214 vzone_getOffset2(VZone* zone, uint8_t era, int32_t year, int32_t month, int32_t day,
 215                 uint8_t dayOfWeek, int32_t millis,
 216                 int32_t monthLength, UErrorCode& status);
 217
 218 /**
 219  * Returns the time zone raw and GMT offset for the given moment
 220  * in time.  Upon return, local-millis = GMT-millis + rawOffset +
 221  * dstOffset.  All computations are performed in the proleptic
 222  * Gregorian calendar.  The default implementation in the TimeZone
 223  * class delegates to the 8-argument getOffset().
 224  *
 225  * @param zone, the vzone to use
 226  * @param date moment in time for which to return offsets, in
 227  * units of milliseconds from January 1, 1970 0:00 GMT, either GMT
 228  * time or local wall time, depending on `local'.
 229  * @param local if true, `date' is local wall time; otherwise it
 230  * is in GMT time.
 231  * @param rawOffset output parameter to receive the raw offset, that
 232  * is, the offset not including DST adjustments
 233  * @param dstOffset output parameter to receive the DST offset,
 234  * that is, the offset to be added to `rawOffset' to obtain the
 235  * total offset between local and GMT time. If DST is not in
 236  * effect, this value is zero; otherwise it is a positive value,
 237  * typically one hour.
 238  * @param ec input-output error code
 239  */
 240 U_CAPI void U_EXPORT2
 241 vzone_getOffset3(VZone* zone, UDate date, UBool local, int32_t& rawOffset,
 242                 int32_t& dstOffset, UErrorCode& ec);
 243
 244 /**
 245  * Sets the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
 246  * to GMT to get local time, before taking daylight savings time into account).
 247  *
 248  * @param zone, the vzone to use
 249  * @param offsetMillis  The new raw GMT offset for this time zone.
 250  */
 251 U_CAPI void U_EXPORT2
 252 vzone_setRawOffset(VZone* zone, int32_t offsetMillis);
 253
 254 /**
 255  * Returns the TimeZone's raw GMT offset (i.e., the number of milliseconds to add
 256  * to GMT to get local time, before taking daylight savings time into account).
 257  *
 258  * @param zone, the vzone to use
 259  * @return   The TimeZone's raw GMT offset.
 260  */
 261 U_CAPI int32_t U_EXPORT2
 262 vzone_getRawOffset(VZone* zone);
 263
 264 /**
 265  * Queries if this time zone uses daylight savings time.
 266  * @param zone, the vzone to use
 267  * @return true if this time zone uses daylight savings time,
 268  * false, otherwise.
 269  */
 270 U_CAPI UBool U_EXPORT2
 271 vzone_useDaylightTime(VZone* zone);
 272
 273 /**
 274  * Queries if the given date is in daylight savings time in
 275  * this time zone.
 276  * This method is wasteful since it creates a new GregorianCalendar and
 277  * deletes it each time it is called. This is a deprecated method
 278  * and provided only for Java compatibility.
 279  *
 280  * @param zone, the vzone to use
 281  * @param date the given UDate.
 282  * @param status Output param filled in with success/error code.
 283  * @return true if the given date is in daylight savings time,
 284  * false, otherwise.
 285  */
 286 U_INTERNAL UBool U_EXPORT2
 287 vzone_inDaylightTime(VZone* zone, UDate date, UErrorCode& status);
 288
 289 /**
 290  * Returns true if this zone has the same rule and offset as another zone.
 291  * That is, if this zone differs only in ID, if at all.
 292  * @param zone, the vzone to use
 293  * @param other the <code>TimeZone</code> object to be compared with
 294  * @return true if the given zone is the same as this one,
 295  * with the possible exception of the ID
 296  */
 297 U_CAPI UBool U_EXPORT2
 298 vzone_hasSameRules(VZone* zone, const VZone* other);
 299
 300 /**
 301  * Gets the first time zone transition after the base time.
 302  * @param zone, the vzone to use
 303  * @param base      The base time.
 304  * @param inclusive Whether the base time is inclusive or not.
 305  * @param result    Receives the first transition after the base time.
 306  * @return  TRUE if the transition is found.
 307  */
 308 U_CAPI UBool U_EXPORT2
 309 vzone_getNextTransition(VZone* zone, UDate base, UBool inclusive, ZTrans* result);
 310
 311 /**
 312  * Gets the most recent time zone transition before the base time.
 313  * @param zone, the vzone to use
 314  * @param base      The base time.
 315  * @param inclusive Whether the base time is inclusive or not.
 316  * @param result    Receives the most recent transition before the base time.
 317  * @return  TRUE if the transition is found.
 318  */
 319 U_CAPI UBool U_EXPORT2
 320 vzone_getPreviousTransition(VZone* zone, UDate base, UBool inclusive, ZTrans* result);
 321
 322 /**
 323  * Returns the number of <code>TimeZoneRule</code>s which represents time transitions,
 324  * for this time zone, that is, all <code>TimeZoneRule</code>s for this time zone except
 325  * <code>InitialTimeZoneRule</code>.  The return value range is 0 or any positive value.
 326  * @param zone, the vzone to use
 327  * @param status    Receives error status code.
 328  * @return The number of <code>TimeZoneRule</code>s representing time transitions.
 329  */
 330 U_CAPI int32_t U_EXPORT2
 331 vzone_countTransitionRules(VZone* zone, UErrorCode& status);
 332
 333 /**
 334  * Return the class ID for this class. This is useful only for comparing to
 335  * a return value from getDynamicClassID(). For example:
 336  * <pre>
 337  * .   Base* polymorphic_pointer = createPolymorphicObject();
 338  * .   if (polymorphic_pointer->getDynamicClassID() ==
 339  * .       erived::getStaticClassID()) ...
 340  * </pre>
 341  * @param zone, the vzone to use
 342  * @return          The class ID for all objects of this class.
 343  */
 344 U_CAPI UClassID U_EXPORT2
 345 vzone_getStaticClassID(VZone* zone);
 346
 347 /**
 348  * Returns a unique class ID POLYMORPHICALLY. Pure virtual override. This
 349  * method is to implement a simple version of RTTI, since not all C++
 350  * compilers support genuine RTTI. Polymorphic operator==() and clone()
 351  * methods call this method.
 352  *
 353  * @param zone, the vzone to use
 354  * @return          The class ID for this object. All objects of a
 355  *                  given class have the same class ID.  Objects of
 356  *                  other classes have different class IDs.
 357  */
 358 U_CAPI UClassID U_EXPORT2
 359 vzone_getDynamicClassID(VZone* zone);
 360
 361 #endif // __VZONE_H
 362
 363 #endif