Initial commit after restructure

modules/modules.go

@@ -0,0 +1,147 @@
+// Copyright Safing ICS Technologies GmbH. Use of this source code is governed by the AGPL license that can be found in the LICENSE file.
+
+package modules
+
+import (
+	"container/list"
+	"os"
+	"time"
+
+	"github.com/tevino/abool"
+)
+
+var modules *list.List
+var addModule chan *Module
+var GlobalShutdown chan struct{}
+var loggingActive bool
+
+type Module struct {
+	Name  string
+	Order uint8
+
+	Start         chan struct{}
+	Active        *abool.AtomicBool
+	startComplete chan struct{}
+
+	Stop         chan struct{}
+	Stopped      *abool.AtomicBool
+	stopComplete chan struct{}
+}
+
+func Register(name string, order uint8) *Module {
+	newModule := &Module{
+		Name:          name,
+		Order:         order,
+		Start:         make(chan struct{}),
+		Active:        abool.NewBool(true),
+		startComplete: make(chan struct{}),
+
+		Stop:         make(chan struct{}),
+		Stopped:      abool.NewBool(false),
+		stopComplete: make(chan struct{}),
+	}
+	addModule <- newModule
+	return newModule
+}
+
+func (module *Module) addToList() {
+	if loggingActive {
+		logger.Infof("Modules: starting %s", module.Name)
+	}
+	for e := modules.Back(); e != nil; e = e.Prev() {
+		if module.Order > e.Value.(*Module).Order {
+			modules.InsertAfter(module, e)
+			return
+		}
+	}
+	modules.PushFront(module)
+}
+
+func (module *Module) stop() {
+	module.Active.UnSet()
+	defer module.Stopped.Set()
+	for {
+		select {
+		case module.Stop <- struct{}{}:
+		case <-module.stopComplete:
+			return
+		case <-time.After(1 * time.Second):
+			if loggingActive {
+				logger.Warningf("Modules: waiting for %s to stop...", module.Name)
+			}
+		}
+	}
+}
+
+func (module *Module) StopComplete() {
+	if loggingActive {
+		logger.Warningf("Modules: stopped %s", module.Name)
+	}
+	module.stopComplete <- struct{}{}
+}
+
+func (module *Module) start() {
+	module.Stopped.UnSet()
+	defer module.Active.Set()
+	for {
+		select {
+		case module.Start <- struct{}{}:
+		case <-module.startComplete:
+			return
+		}
+	}
+}
+
+func (module *Module) StartComplete() {
+	if loggingActive {
+		logger.Infof("Modules: starting %s", module.Name)
+	}
+	module.startComplete <- struct{}{}
+}
+
+func InitiateFullShutdown() {
+	close(GlobalShutdown)
+}
+
+func fullStop() {
+	for e := modules.Back(); e != nil; e = e.Prev() {
+		if e.Value.(*Module).Active.IsSet() {
+			e.Value.(*Module).stop()
+		}
+	}
+}
+
+func run() {
+	select {
+	case <-loggerRegistered:
+		logger.Info("Modules: starting")
+		loggingActive = true
+	case <-time.After(1 * time.Second):
+	}
+
+	for {
+		select {
+		case <-GlobalShutdown:
+			if loggingActive {
+				logger.Warning("Modules: stopping")
+			}
+			fullStop()
+			os.Exit(0)
+		case m := <-addModule:
+			m.addToList()
+			// go m.start()
+		}
+	}
+}
+
+func init() {
+
+	modules = list.New()
+	addModule = make(chan *Module, 10)
+	GlobalShutdown = make(chan struct{})
+	loggerRegistered = make(chan struct{}, 1)
+	loggingActive = false
+
+	go run()
+
+}