51 lines
1.3 KiB
Go
51 lines
1.3 KiB
Go
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// Package daemon provides utilities for daemons.
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package daemon
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import "io"
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import "os"
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import "syscall"
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import "strconv"
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import "os/signal"
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// PidFile is a string that contains a path to a pidfile.
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type PidFile string
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// Start writes to the pidfile.
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func (pidfile PidFile) Start () error {
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return os.WriteFile(string(pidfile), []byte(strconv.Itoa(os.Getpid())), 0644)
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}
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// Close deletes the pidfile.
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func (pidfile PidFile) Close () error {
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return os.Remove(string(pidfile))
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}
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// Empty returns true if the object is zero value (an empty string).
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func (pidfile PidFile) Empty () bool {
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return pidfile == ""
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}
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// OnSigint calls the specified function once sigint is recieved. This function
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// does not block, and spawns a goroutine that waits. For this reason, the
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// callback must be safe to call concurrently.
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func OnSigint (callback func ()) {
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go func () {
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sigintNotify := make(chan os.Signal, 1)
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signal.Notify(sigintNotify, os.Interrupt, syscall.SIGTERM)
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<-sigintNotify
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callback()
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} ()
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}
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// CloseOnSigint is like OnSigint, but takes an io.Closer.
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func CloseOnSigint (closer io.Closer) {
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OnSigint(func () { closer.Close() })
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}
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// ShutdownOnSigint is like OnSigint, but takes an object with a Shutdown()
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// method.
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func ShutdownOnSigint (shutdowner interface { Shutdown() error }) {
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OnSigint(func () { shutdowner.Shutdown() })
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}
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