56 lines
1.9 KiB
Go
56 lines
1.9 KiB
Go
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// Copyright (c) 2016 Uber Technologies, Inc.
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//
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// Permission is hereby granted, free of charge, to any person obtaining a copy
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// of this software and associated documentation files (the "Software"), to deal
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// in the Software without restriction, including without limitation the rights
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// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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// copies of the Software, and to permit persons to whom the Software is
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// furnished to do so, subject to the following conditions:
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//
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// The above copyright notice and this permission notice shall be included in
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// all copies or substantial portions of the Software.
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//
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// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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// THE SOFTWARE.
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package atomic
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// Error is an atomic type-safe wrapper around Value for errors
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type Error struct{ v Value }
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// errorHolder is non-nil holder for error object.
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// atomic.Value panics on saving nil object, so err object needs to be
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// wrapped with valid object first.
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type errorHolder struct{ err error }
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// NewError creates new atomic error object
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func NewError(err error) *Error {
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e := &Error{}
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if err != nil {
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e.Store(err)
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}
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return e
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}
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// Load atomically loads the wrapped error
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func (e *Error) Load() error {
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v := e.v.Load()
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if v == nil {
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return nil
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}
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eh := v.(errorHolder)
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return eh.err
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}
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// Store atomically stores error.
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// NOTE: a holder object is allocated on each Store call.
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func (e *Error) Store(err error) {
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e.v.Store(errorHolder{err: err})
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}
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