59 lines
1.4 KiB
Go
59 lines
1.4 KiB
Go
package atomics
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import (
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"sync/atomic"
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"time"
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"unsafe"
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)
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// Time provides user-friendly means of performing atomic operations on time.Time types.
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type Time struct{ ptr unsafe.Pointer }
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// NewTime will return a new Time instance initialized with zero value.
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func NewTime() *Time {
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var v time.Time
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return &Time{
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ptr: unsafe.Pointer(&v),
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}
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}
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// Store will atomically store time.Time value in address contained within v.
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func (v *Time) Store(val time.Time) {
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atomic.StorePointer(&v.ptr, unsafe.Pointer(&val))
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}
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// Load will atomically load time.Time value at address contained within v.
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func (v *Time) Load() time.Time {
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return *(*time.Time)(atomic.LoadPointer(&v.ptr))
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}
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// CAS performs a compare-and-swap for a(n) time.Time value at address contained within v.
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func (v *Time) CAS(cmp, swp time.Time) bool {
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for {
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// Load current value at address
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ptr := atomic.LoadPointer(&v.ptr)
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cur := *(*time.Time)(ptr)
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// Perform comparison against current
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if !(cur.Equal(cmp)) {
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return false
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}
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// Attempt to replace pointer
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if atomic.CompareAndSwapPointer(
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&v.ptr,
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ptr,
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unsafe.Pointer(&swp),
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) {
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return true
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}
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}
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}
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// Swap atomically stores new time.Time value into address contained within v, and returns previous value.
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func (v *Time) Swap(swp time.Time) time.Time {
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ptr := unsafe.Pointer(&swp)
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ptr = atomic.SwapPointer(&v.ptr, ptr)
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return *(*time.Time)(ptr)
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}
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