36 lines
1.1 KiB
Go
36 lines
1.1 KiB
Go
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// This file originates from Docker/Moby,
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// https://github.com/moby/moby/blob/master/pkg/reexec/reexec.go
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// Licensed under Apache License 2.0: https://github.com/moby/moby/blob/master/LICENSE
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// Copyright 2013-2018 Docker, Inc.
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//
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// Package reexec facilitates the busybox style reexec of the docker binary that
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// we require because of the forking limitations of using Go. Handlers can be
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// registered with a name and the argv 0 of the exec of the binary will be used
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// to find and execute custom init paths.
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package reexec
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import (
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"fmt"
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"os"
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)
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var registeredInitializers = make(map[string]func())
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// Register adds an initialization func under the specified name
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func Register(name string, initializer func()) {
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if _, exists := registeredInitializers[name]; exists {
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panic(fmt.Sprintf("reexec func already registered under name %q", name))
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}
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registeredInitializers[name] = initializer
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}
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// Init is called as the first part of the exec process and returns true if an
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// initialization function was called.
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func Init() bool {
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if initializer, ok := registeredInitializers[os.Args[0]]; ok {
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initializer()
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return true
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}
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return false
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}
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