github.1485827954.workers.dev/ethereum/go-ethereum@v1.14.3/internal/reexec/reexec.go (about)

     1  // This file originates from Docker/Moby,
     2  // https://github.com/moby/moby/blob/master/pkg/reexec/reexec.go
     3  // Licensed under Apache License 2.0: https://github.com/moby/moby/blob/master/LICENSE
     4  // Copyright 2013-2018 Docker, Inc.
     5  //
     6  // Package reexec facilitates the busybox style reexec of the docker binary that
     7  // we require because of the forking limitations of using Go.  Handlers can be
     8  // registered with a name and the argv 0 of the exec of the binary will be used
     9  // to find and execute custom init paths.
    10  package reexec
    11  
    12  import (
    13  	"fmt"
    14  	"os"
    15  )
    16  
    17  var registeredInitializers = make(map[string]func())
    18  
    19  // Register adds an initialization func under the specified name
    20  func Register(name string, initializer func()) {
    21  	if _, exists := registeredInitializers[name]; exists {
    22  		panic(fmt.Sprintf("reexec func already registered under name %q", name))
    23  	}
    24  	registeredInitializers[name] = initializer
    25  }
    26  
    27  // Init is called as the first part of the exec process and returns true if an
    28  // initialization function was called.
    29  func Init() bool {
    30  	if initializer, ok := registeredInitializers[os.Args[0]]; ok {
    31  		initializer()
    32  		return true
    33  	}
    34  	return false
    35  }