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67 lines
1.7 KiB
Go
67 lines
1.7 KiB
Go
package reexec
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import (
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"fmt"
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"os"
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"os/exec"
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"path/filepath"
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)
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var (
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registeredInitializers = make(map[string]func())
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initWasCalled = false
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)
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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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initializer, exists := registeredInitializers[os.Args[0]]
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initWasCalled = true
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if exists {
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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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func panicIfNotInitialized() {
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if !initWasCalled {
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// The reexec package is used to run subroutines in
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// subprocesses which would otherwise have unacceptable side
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// effects on the main thread. If you found this error, then
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// your program uses a package which needs to do this. In
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// order for that to work, main() should start with this
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// boilerplate, or an equivalent:
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// if reexec.Init() {
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// return
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// }
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panic("a library subroutine needed to run a subprocess, but reexec.Init() was not called in main()")
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}
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}
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func naiveSelf() string {
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name := os.Args[0]
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if filepath.Base(name) == name {
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if lp, err := exec.LookPath(name); err == nil {
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return lp
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}
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}
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// handle conversion of relative paths to absolute
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if absName, err := filepath.Abs(name); err == nil {
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return absName
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}
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// if we couldn't get absolute name, return original
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// (NOTE: Go only errors on Abs() if os.Getwd fails)
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return name
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}
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