diff options
Diffstat (limited to 'vendor/github.com/coreos/go-systemd/v22/daemon/sdnotify.go')
-rw-r--r-- | vendor/github.com/coreos/go-systemd/v22/daemon/sdnotify.go | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/vendor/github.com/coreos/go-systemd/v22/daemon/sdnotify.go b/vendor/github.com/coreos/go-systemd/v22/daemon/sdnotify.go new file mode 100644 index 000000000..ba4ae31f1 --- /dev/null +++ b/vendor/github.com/coreos/go-systemd/v22/daemon/sdnotify.go @@ -0,0 +1,84 @@ +// Copyright 2014 Docker, Inc. +// Copyright 2015-2018 CoreOS, Inc. +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use this file except in compliance with the License. +// You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. +// + +// Package daemon provides a Go implementation of the sd_notify protocol. +// It can be used to inform systemd of service start-up completion, watchdog +// events, and other status changes. +// +// https://www.freedesktop.org/software/systemd/man/sd_notify.html#Description +package daemon + +import ( + "net" + "os" +) + +const ( + // SdNotifyReady tells the service manager that service startup is finished + // or the service finished loading its configuration. + SdNotifyReady = "READY=1" + + // SdNotifyStopping tells the service manager that the service is beginning + // its shutdown. + SdNotifyStopping = "STOPPING=1" + + // SdNotifyReloading tells the service manager that this service is + // reloading its configuration. Note that you must call SdNotifyReady when + // it completed reloading. + SdNotifyReloading = "RELOADING=1" + + // SdNotifyWatchdog tells the service manager to update the watchdog + // timestamp for the service. + SdNotifyWatchdog = "WATCHDOG=1" +) + +// SdNotify sends a message to the init daemon. It is common to ignore the error. +// If `unsetEnvironment` is true, the environment variable `NOTIFY_SOCKET` +// will be unconditionally unset. +// +// It returns one of the following: +// (false, nil) - notification not supported (i.e. NOTIFY_SOCKET is unset) +// (false, err) - notification supported, but failure happened (e.g. error connecting to NOTIFY_SOCKET or while sending data) +// (true, nil) - notification supported, data has been sent +func SdNotify(unsetEnvironment bool, state string) (bool, error) { + socketAddr := &net.UnixAddr{ + Name: os.Getenv("NOTIFY_SOCKET"), + Net: "unixgram", + } + + // NOTIFY_SOCKET not set + if socketAddr.Name == "" { + return false, nil + } + + if unsetEnvironment { + if err := os.Unsetenv("NOTIFY_SOCKET"); err != nil { + return false, err + } + } + + conn, err := net.DialUnix(socketAddr.Net, nil, socketAddr) + // Error connecting to NOTIFY_SOCKET + if err != nil { + return false, err + } + defer conn.Close() + + if _, err = conn.Write([]byte(state)); err != nil { + return false, err + } + return true, nil +} |