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Diffstat (limited to 'vendor/golang.org/x/net/context/go17.go')
-rw-r--r-- | vendor/golang.org/x/net/context/go17.go | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/context/go17.go b/vendor/golang.org/x/net/context/go17.go new file mode 100644 index 00000000..d20f52b7 --- /dev/null +++ b/vendor/golang.org/x/net/context/go17.go @@ -0,0 +1,72 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +build go1.7 + +package context + +import ( + "context" // standard library's context, as of Go 1.7 + "time" +) + +var ( + todo = context.TODO() + background = context.Background() +) + +// Canceled is the error returned by Context.Err when the context is canceled. +var Canceled = context.Canceled + +// DeadlineExceeded is the error returned by Context.Err when the context's +// deadline passes. +var DeadlineExceeded = context.DeadlineExceeded + +// WithCancel returns a copy of parent with a new Done channel. The returned +// context's Done channel is closed when the returned cancel function is called +// or when the parent context's Done channel is closed, whichever happens first. +// +// Canceling this context releases resources associated with it, so code should +// call cancel as soon as the operations running in this Context complete. +func WithCancel(parent Context) (ctx Context, cancel CancelFunc) { + ctx, f := context.WithCancel(parent) + return ctx, CancelFunc(f) +} + +// WithDeadline returns a copy of the parent context with the deadline adjusted +// to be no later than d. If the parent's deadline is already earlier than d, +// WithDeadline(parent, d) is semantically equivalent to parent. The returned +// context's Done channel is closed when the deadline expires, when the returned +// cancel function is called, or when the parent context's Done channel is +// closed, whichever happens first. +// +// Canceling this context releases resources associated with it, so code should +// call cancel as soon as the operations running in this Context complete. +func WithDeadline(parent Context, deadline time.Time) (Context, CancelFunc) { + ctx, f := context.WithDeadline(parent, deadline) + return ctx, CancelFunc(f) +} + +// WithTimeout returns WithDeadline(parent, time.Now().Add(timeout)). +// +// Canceling this context releases resources associated with it, so code should +// call cancel as soon as the operations running in this Context complete: +// +// func slowOperationWithTimeout(ctx context.Context) (Result, error) { +// ctx, cancel := context.WithTimeout(ctx, 100*time.Millisecond) +// defer cancel() // releases resources if slowOperation completes before timeout elapses +// return slowOperation(ctx) +// } +func WithTimeout(parent Context, timeout time.Duration) (Context, CancelFunc) { + return WithDeadline(parent, time.Now().Add(timeout)) +} + +// WithValue returns a copy of parent in which the value associated with key is +// val. +// +// Use context Values only for request-scoped data that transits processes and +// APIs, not for passing optional parameters to functions. +func WithValue(parent Context, key interface{}, val interface{}) Context { + return context.WithValue(parent, key, val) +} |