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path: root/vendor/github.com/docker/docker/pkg/reexec/reexec.go
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package reexec

import (
    "fmt"
    "os"
    "os/exec"
    "path/filepath"
)

var registeredInitializers = make(map[string]func())

// Register adds an initialization func under the specified name
func Register(name string, initializer func()) {
    if _, exists := registeredInitializers[name]; exists {
        panic(fmt.Sprintf("reexec func already registered under name %q", name))
    }

    registeredInitializers[name] = initializer
}

// Init is called as the first part of the exec process and returns true if an
// initialization function was called.
func Init() bool {
    initializer, exists := registeredInitializers[os.Args[0]]
    if exists {
        initializer()

        return true
    }
    return false
}

func naiveSelf() string {
    name := os.Args[0]
    if filepath.Base(name) == name {
        if lp, err := exec.LookPath(name); err == nil {
            return lp
        }
    }
    // handle conversion of relative paths to absolute
    if absName, err := filepath.Abs(name); err == nil {
        return absName
    }
    // if we couldn't get absolute name, return original
    // (NOTE: Go only errors on Abs() if os.Getwd fails)
    return name
}