log/handler_go13.go


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// +build !go1.4

package log

import (
    "sync/atomic"
    "unsafe"
)

// swapHandler wraps another handler that may be swapped out
// dynamically at runtime in a thread-safe fashion.
type swapHandler struct {
    handler unsafe.Pointer
}

func (h *swapHandler) Log(r *Record) error {
    return h.Get().Log(r)
}

func (h *swapHandler) Get() Handler {
    return *(*Handler)(atomic.LoadPointer(&h.handler))
}

func (h *swapHandler) Swap(newHandler Handler) {
    atomic.StorePointer(&h.handler, unsafe.Pointer(&newHandler))
}