internal/kobject: pass action kind for range

Useful for handling most uevents.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/earlyinit/main.go

@@ -19,6 +19,7 @@ import (
 	"hakurei.app/internal/kobject"
 	"hakurei.app/internal/report"
 	"hakurei.app/internal/uevent"
+	"hakurei.app/message"
 )
 
 var r report.Reporter
@@ -79,6 +80,8 @@ const (
 	// optionSystem specifies devpath of the system device.
 	optionSystem = "system"
 
+	// flagVerbose increases output verbosity.
+	flagVerbose = "verbose"
 	// flagStrict sets [report.DStrict] on r.
 	flagStrict = "strict"
 	// flagNoRecover sets [report.DNoRecover] on r.
@@ -116,6 +119,9 @@ func main() {
 		r.SetFlags(flag)
 	}
 
+	msg := message.New(log.Default())
+	msg.SwapVerbose(slices.Contains(flags, flagVerbose))
+
 	mustSyscall("mount devtmpfs", Mount(
 		"devtmpfs",
 		"/dev/",
@@ -193,7 +199,7 @@ func main() {
 	must1(rand.Read(uuid[:]))
 	ctx, cancel := context.WithCancel(context.Background())
 
-	go consume(ctx, &r, conn, uuid, events)
+	go consume(ctx, msg, &r, conn, uuid, events)
 	s := kobject.New(uuid, func(o *kobject.Object, env map[string]string) {
 		log.Printf("change %s: %q", o.DevPath, env)
 	}, func(err error) {

cmd/earlyinit/mount.go

@@ -12,6 +12,7 @@ import (
 	"hakurei.app/check"
 	"hakurei.app/fhs"
 	"hakurei.app/internal/kobject"
+	"hakurei.app/internal/uevent"
 )
 
 // mustMountSystem waits for and mounts a system device matching pattern.
@@ -26,8 +27,9 @@ func mustMountSystem(
 	for {
 		var matchErr error
 		var systemPath *check.Absolute
-		s.Range(c, func(o *kobject.Object) bool {
-			if o.Subsystem != "block" ||
+		s.Range(c, func(o *kobject.Object, act uevent.KobjectAction) bool {
+			if (act != uevent.KOBJ_ADD && act != uevent.KOBJ_CHANGE) ||
+				o.Subsystem != "block" ||
 				o.Env["DEVTYPE"] != "disk" {
 				return true
 			}

cmd/earlyinit/uevent.go

@@ -2,12 +2,12 @@ package main
 
 import (
 	"context"
-	"log"
 	"time"
 
 	"hakurei.app/fhs"
 	"hakurei.app/internal/report"
 	"hakurei.app/internal/uevent"
+	"hakurei.app/message"
 )
 
 // newRejectColdboot returns a function to be called on every subsequent pending
@@ -56,6 +56,7 @@ func newRejectColdboot() func() bool {
 // consume continuously consumes events from conn with retries.
 func consume(
 	ctx context.Context,
+	msg message.Msg,
 	r *report.Reporter,
 	conn *uevent.Conn,
 	uuid uevent.UUID,
@@ -67,7 +68,7 @@ func consume(
 	coldboot := true
 retry:
 	if dispatchErr := conn.Consume(ctx, fhs.Sys, &uuid, events, coldboot, func(path string) {
-		log.Println("coldboot visited", path)
+		msg.Verbose("coldboot visited", path)
 	}, func(err error) bool {
 		if _, ok := err.(uevent.NeedsColdboot); ok && !nextColdboot() {
 			r.Dispatch(

internal/kobject/kobject.go

@@ -101,7 +101,7 @@ func (o *Object) update(env map[string]string, strip bool) {
 // A pendingIterator is a callback currently iterating through objects targeted
 // by ongoing events.
 type pendingIterator struct {
-	f    func(o *Object) bool
+	f    func(o *Object, act uevent.KobjectAction) bool
 	done chan<- struct{}
 }
 
@@ -150,12 +150,12 @@ func (s *State) deleteIter(p *pendingIterator) {
 }
 
 // dispatchIter broadcasts an [Object] to all alive iterators.
-func (s *State) dispatchIter(o *Object) {
+func (s *State) dispatchIter(o *Object, act uevent.KobjectAction) {
 	s.iterMu.Lock()
 	defer s.iterMu.Unlock()
 
 	for _, p := range s.iter {
-		if !p.f(o) {
+		if !p.f(o, act) {
 			s.deleteIter(p)
 			close(p.done)
 		}
@@ -165,14 +165,17 @@ func (s *State) dispatchIter(o *Object) {
 // Range calls f on all current and upcoming [Object] values tracked by s until
 // f returns false or the context is cancelled. f must not retain o or modify
 // the value it points to.
-func (s *State) Range(ctx context.Context, f func(o *Object) bool) {
+func (s *State) Range(
+	ctx context.Context,
+	f func(o *Object, act uevent.KobjectAction) bool,
+) {
 	done := make(chan struct{})
 	p := pendingIterator{f, done}
 
 	s.iterMu.Lock()
 	s.ueventMu.RLock()
 	for _, o := range s.uevent {
-		if !f(o) {
+		if !f(o, uevent.KOBJ_ADD) {
 			s.ueventMu.RUnlock()
 			s.iterMu.Unlock()
 			return
@@ -296,13 +299,13 @@ func (s *State) processEvent(e *Event) {
 		return
 	}
 
-	switch e.Action {
+	switch act := e.Action; act {
 	case uevent.KOBJ_ADD:
 		if e.Synth == nil {
 			if o, ok := s.uevent[e.DevPath]; ok {
 				s.reportErr(e.NewError(EDuplicateAdd, o))
 				o.merge(e.Env)
-				s.dispatchIter(o)
+				s.dispatchIter(o, act)
 				return
 			}
 		}
@@ -312,7 +315,7 @@ func (s *State) processEvent(e *Event) {
 		}
 		o.merge(e.Env)
 		s.uevent[e.DevPath] = o
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	case uevent.KOBJ_REMOVE:
@@ -338,14 +341,14 @@ func (s *State) processEvent(e *Event) {
 			o = e.makeColdboot()
 			o.merge(e.Env)
 			s.uevent[e.DevPath] = o
-			s.dispatchIter(o)
+			s.dispatchIter(o, act)
 			return
 		}
 		o.update(e.Env, true)
 		if s.handleChange != nil {
 			s.handleChange(o, e.Env)
 		}
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	case uevent.KOBJ_MOVE:
@@ -368,7 +371,7 @@ func (s *State) processEvent(e *Event) {
 		o.merge(e.Env)
 		s.uevent[e.DevPath] = o
 		o.DevPath = e.DevPath
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	case uevent.KOBJ_ONLINE:
@@ -384,7 +387,7 @@ func (s *State) processEvent(e *Event) {
 			s.reportErr(e.NewError(EUnexpectedOffline, o))
 		}
 		o.Offline = false
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	case uevent.KOBJ_OFFLINE:
@@ -400,7 +403,7 @@ func (s *State) processEvent(e *Event) {
 			s.reportErr(e.NewError(EUnexpectedOffline, o))
 		}
 		o.Offline = true
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	case uevent.KOBJ_BIND:
@@ -416,7 +419,7 @@ func (s *State) processEvent(e *Event) {
 		}
 		o.State = StateBound
 		o.merge(e.Env)
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	case uevent.KOBJ_UNBIND:
@@ -432,7 +435,7 @@ func (s *State) processEvent(e *Event) {
 		}
 		o.State = StateNew
 		o.Driver = ""
-		s.dispatchIter(o)
+		s.dispatchIter(o, act)
 		return
 
 	default: // not reached

internal/kobject/kobject_test.go

@@ -388,7 +388,9 @@ func TestIter(t *testing.T) {
 			"SEQNUM=1",
 		}}
 		synctest.Wait()
-		s.Range(t.Context(), func(o *Object) bool { return false })
+		s.Range(t.Context(), func(*Object, uevent.KobjectAction) bool {
+			return false
+		})
 
 		var got []*Object
 		check := func(want []*Object) {
@@ -405,7 +407,7 @@ func TestIter(t *testing.T) {
 		defer cancel()
 		var done bool
 		wg.Go(func() {
-			s.Range(ctx, func(o *Object) bool {
+			s.Range(ctx, func(o *Object, _ uevent.KobjectAction) bool {
 				got = append(got, o.Clone())
 				return !done
 			})
@@ -437,7 +439,11 @@ func TestIter(t *testing.T) {
 			},
 		})
 
-		wg.Go(func() { s.Range(ctx, func(*Object) bool { return true }) })
+		wg.Go(func() {
+			s.Range(ctx, func(*Object, uevent.KobjectAction) bool {
+				return true
+			})
+		})
 		synctest.Wait()
 
 		iter := reflect.ValueOf(s).Elem().FieldByName("iter")