diff options
Diffstat (limited to 'sd_login/type_monitor.go')
-rw-r--r-- | sd_login/type_monitor.go | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/sd_login/type_monitor.go b/sd_login/type_monitor.go new file mode 100644 index 0000000..50f601a --- /dev/null +++ b/sd_login/type_monitor.go @@ -0,0 +1,106 @@ +// Copyright (C) 2016 Luke Shumaker <lukeshu@sbcglobal.net> +// +// 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 sd_login + +import ( + "git.lukeshu.com/go/libgnulinux/inotify" + "golang.org/x/sys/unix" +) + +// Monitor monitors several types of events, so you don't have to do +// busy-polling. +// +// However, Monitor won't actually give you the event that happened, +// you'll need to read it yourself. +type Monitor struct { + in *inotify.Inotify +} + +type MonitorCategory uint + +const ( + MonitorSeats MonitorCategory = 1 << iota + MonitorSessions + MonitorUsers + MonitorMachines + + MonitorAll = MonitorSeats | MonitorSessions | MonitorUsers | MonitorMachines +) + +func NewMonitor(categories MonitorCategory) (*Monitor, error) { + if categories == 0 { + return nil, unix.EINVAL + } + + in, err := inotify.InotifyInit1(inotify.IN_CLOEXEC) + if err != nil { + return nil, err + } + + if categories&MonitorSeats != 0 { + _, err := in.AddWatch("/run/systemd/seats/", inotify.IN_MOVED_TO|inotify.IN_DELETE) + if err != nil { + in.Close() + return nil, err + } + } + + if categories&MonitorSessions != 0 { + _, err := in.AddWatch("/run/systemd/sessions/", inotify.IN_MOVED_TO|inotify.IN_DELETE) + if err != nil { + in.Close() + return nil, err + } + } + + if categories&MonitorUsers != 0 { + _, err := in.AddWatch("/run/systemd/users/", inotify.IN_MOVED_TO|inotify.IN_DELETE) + if err != nil { + in.Close() + return nil, err + } + } + + if categories&MonitorMachines != 0 { + _, err := in.AddWatch("/run/systemd/machines/", inotify.IN_MOVED_TO|inotify.IN_DELETE) + if err != nil { + in.Close() + return nil, err + } + } + + return &Monitor{in: in}, nil +} + +func (m *Monitor) Close() error { + return m.in.Close() +} + +func (m *Monitor) Flush() error { + for { + ev, err := m.in.ReadNonblock() + if err != nil { + return err + } + if ev.Wd < 0 { + return nil + } + } +} + +func (m *Monitor) Wait() error { + _, err := m.in.ReadBlock() + return err +} |