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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#ifndef vm_DateObject_h_
#define vm_DateObject_h_
#include "js/Date.h"
#include "js/Value.h"
#include "vm/DateTime.h"
#include "vm/NativeObject.h"
namespace js {
class DateObject : public NativeObject {
// Time in milliseconds since the (Unix) epoch.
//
// The stored value is guaranteed to be a Double.
static const uint32_t UTC_TIME_SLOT = 0;
// Raw time zone offset in seconds, i.e. without daylight saving adjustment,
// of the current system zone.
//
// This value is exclusively used to verify the cached slots are still valid.
//
// It is NOT the return value of Date.prototype.getTimezoneOffset()!
//
// The stored value is either an Int32 or Undefined.
static const uint32_t UTC_TIME_ZONE_OFFSET_SLOT = 1;
/*
* Cached slots holding local properties of the date.
* These are undefined until the first actual lookup occurs
* and are reset to undefined whenever the date's time is modified.
*
* - LOCAL_TIME_SLOT is either a Double or Undefined.
* - The remaining slots store either Int32, NaN, or Undefined values.
*/
static const uint32_t COMPONENTS_START_SLOT = 2;
static const uint32_t LOCAL_TIME_SLOT = COMPONENTS_START_SLOT + 0;
static const uint32_t LOCAL_YEAR_SLOT = COMPONENTS_START_SLOT + 1;
static const uint32_t LOCAL_MONTH_SLOT = COMPONENTS_START_SLOT + 2;
static const uint32_t LOCAL_DATE_SLOT = COMPONENTS_START_SLOT + 3;
static const uint32_t LOCAL_DAY_SLOT = COMPONENTS_START_SLOT + 4;
/*
* Unlike the above slots that hold LocalTZA-adjusted component values,
* LOCAL_SECONDS_INTO_YEAR_SLOT holds a composite value that can be used
* to compute LocalTZA-adjusted hours, minutes, and seconds values.
* Specifically, LOCAL_SECONDS_INTO_YEAR_SLOT holds the number of
* LocalTZA-adjusted seconds into the year. Unix timestamps ignore leap
* seconds, so recovering hours/minutes/seconds requires only trivial
* division/modulus operations.
*/
static const uint32_t LOCAL_SECONDS_INTO_YEAR_SLOT =
COMPONENTS_START_SLOT + 5;
static const uint32_t RESERVED_SLOTS = LOCAL_SECONDS_INTO_YEAR_SLOT + 1;
public:
static const JSClass class_;
static const JSClass protoClass_;
js::DateTimeInfo::ForceUTC forceUTC() const;
JS::ClippedTime clippedTime() const {
double t = getFixedSlot(UTC_TIME_SLOT).toDouble();
JS::ClippedTime clipped = JS::TimeClip(t);
MOZ_ASSERT(mozilla::NumbersAreIdentical(clipped.toDouble(), t));
return clipped;
}
/**
* Return the time in milliseconds since the epoch. The value is guaranteed to
* be a Double.
*/
const js::Value& UTCTime() const { return getFixedSlot(UTC_TIME_SLOT); }
/**
* Return the cached local time. The value is either a Double or Undefined.
*/
const js::Value& localTime() const {
return getReservedSlot(LOCAL_TIME_SLOT);
}
// Set UTC time to a given time and invalidate cached local time.
void setUTCTime(JS::ClippedTime t);
void setUTCTime(JS::ClippedTime t, MutableHandleValue vp);
// Cache the local time, year, month, and so forth of the object.
// If UTC time is not finite (e.g., NaN), the local time
// slots will be set to the UTC time without conversion.
void fillLocalTimeSlots();
/**
* Return the cached local year. The value is either an Int32, NaN, or
* Undefined.
*/
const js::Value& localYear() const {
return getReservedSlot(LOCAL_YEAR_SLOT);
}
/**
* Return the cached local month. The value is either an Int32, NaN, or
* Undefined.
*/
const js::Value& localMonth() const {
return getReservedSlot(LOCAL_MONTH_SLOT);
}
/**
* Return the cached local day of month. The value is either an Int32, NaN,
* or Undefined.
*/
const js::Value& localDate() const {
return getReservedSlot(LOCAL_DATE_SLOT);
}
/**
* Return the cached local day of week. The value is either an Int32, NaN,
* or Undefined.
*/
const js::Value& localDay() const { return getReservedSlot(LOCAL_DAY_SLOT); }
/**
* Return the cached local seconds of year. The value is either an Int32, NaN,
* or Undefined.
*/
const js::Value& localSecondsIntoYear() const {
return getReservedSlot(LOCAL_SECONDS_INTO_YEAR_SLOT);
}
};
} // namespace js
#endif // vm_DateObject_h_