feat(xwm): X to Wayland text selection transfers with INCR, buffer pool and timeouts

commit: 4035b0078c07189194f282cc1e947f5a4ef64b87
author: brice · 10h ago · 2026-10-22 16:15 UTC
parent: 889daca
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

6 files · +774 -7

M Makefile +1 -1


@@ -70,7 +70,7 @@ adapter-imports:
70	70		[ -z "$$bad" ] \|\| { echo "$$bad"; echo 'adapter imports another adapter: use ports or a shared library (Makefile ADAPTER_LIBS)' >&2; exit 1; }
71	71		# Fast, mandatory guards for tiled content publications and SHM copies.
72	72		perf-check:
73		-	CGO_ENABLED=0 go test ./internal/core ./internal/app ./internal/adapters/drm ./internal/adapters/headless ./internal/adapters/vulkan ./internal/adapters/wayland ./internal/adapters/outputkit/capture ./internal/adapters/screencast ./internal/adapters/wayland/xwm -run '^(TestAnimateAllocations\|TestPublishAllocations\|TestPublishSubscribersAllocations\|TestPublishStashSlideAllocations\|TestPublishOverviewAllocations\|TestPublishLeavingAllocations\|TestOutputRoutingAllocations\|TestReportSeenAllocations\|TestFrameLifecycleTransitionsAllocations\|TestFullscreenShownAllocations\|TestFrameDecisionAllocations\|TestCommitFrameAllocations\|TestColorPipelineAllocations\|TestShownBySnapshotAllocations\|TestFlipShowsAllocations\|TestMRUNoteFocusDoesNotAllocateWhenSettled\|TestDueFramesAllocations\|TestRenderSteadyStateAllocations\|TestRenderSteadyStateDMABufAllocations\|TestSceneOpaqueRegionAllocations\|TestSceneDeltaAllocations\|TestAccountFlipAllocations\|TestFlipDoneAllocations\|TestSceneWalkUnchangedTiledSHM\|TestTiledCommitPublishAllocations\|TestCapturedCommitApplyAllocations\|TestCapturedViewportApplyAllocations\|TestEffectiveInputEmptyTreeAllocations\|TestHeadlessTiledSHMCallbackAndCopyBudget\|TestReleaseHeldAllocations\|TestCommitDamageAllocations\|TestEmitContentAllocations\|TestPresentationPushAllocations\|TestAnimatingFrameSendAllocations\|TestContentBatchCycleAllocations\|TestWriteMappedAllocations\|TestCapturedForwardAllocations\|TestCommandForwardAllocations\|TestOutboxQueuedDeliveryAllocations\|TestCastFrameAllocations\|TestCastProducerAllocations\|TestCaptureCycleAllocations\|TestLogScenesAllocations\|TestOverviewNamedRowsAllocations\|TestBufferContentAllocations\|TestDueFramesFireScratch\|TestRetireSemaphoreAllocatesNothing\|TestTableLookupAllocations\|TestTableInsertRemoveAllocations\|TestPropertyUnchangedAllocations\|TestDispatchAllocations\|TestConfigureFlushAllocations\|TestFocusAllocations\|TestSpaceAllocations\|TestUnmanagedGeometryAllocations\|TestFocusInUnmanagedAllocations\|TestUnmanagedPublishAllocations\|TestUnmanagedHitAllocations\|TestOverrideMovedUnchangedAllocations\|TestFullscreenConfigureAllocations\|TestKeyboardGrabSyncAllocations)$$' -count=1
	73	+	CGO_ENABLED=0 go test ./internal/core ./internal/app ./internal/adapters/drm ./internal/adapters/headless ./internal/adapters/vulkan ./internal/adapters/wayland ./internal/adapters/outputkit/capture ./internal/adapters/screencast ./internal/adapters/wayland/xwm -run '^(TestAnimateAllocations\|TestPublishAllocations\|TestPublishSubscribersAllocations\|TestPublishStashSlideAllocations\|TestPublishOverviewAllocations\|TestPublishLeavingAllocations\|TestOutputRoutingAllocations\|TestReportSeenAllocations\|TestFrameLifecycleTransitionsAllocations\|TestFullscreenShownAllocations\|TestFrameDecisionAllocations\|TestCommitFrameAllocations\|TestColorPipelineAllocations\|TestShownBySnapshotAllocations\|TestFlipShowsAllocations\|TestMRUNoteFocusDoesNotAllocateWhenSettled\|TestDueFramesAllocations\|TestRenderSteadyStateAllocations\|TestRenderSteadyStateDMABufAllocations\|TestSceneOpaqueRegionAllocations\|TestSceneDeltaAllocations\|TestAccountFlipAllocations\|TestFlipDoneAllocations\|TestSceneWalkUnchangedTiledSHM\|TestTiledCommitPublishAllocations\|TestCapturedCommitApplyAllocations\|TestCapturedViewportApplyAllocations\|TestEffectiveInputEmptyTreeAllocations\|TestHeadlessTiledSHMCallbackAndCopyBudget\|TestReleaseHeldAllocations\|TestCommitDamageAllocations\|TestEmitContentAllocations\|TestPresentationPushAllocations\|TestAnimatingFrameSendAllocations\|TestContentBatchCycleAllocations\|TestWriteMappedAllocations\|TestCapturedForwardAllocations\|TestCommandForwardAllocations\|TestOutboxQueuedDeliveryAllocations\|TestCastFrameAllocations\|TestCastProducerAllocations\|TestCaptureCycleAllocations\|TestLogScenesAllocations\|TestOverviewNamedRowsAllocations\|TestBufferContentAllocations\|TestDueFramesFireScratch\|TestRetireSemaphoreAllocatesNothing\|TestTableLookupAllocations\|TestTableInsertRemoveAllocations\|TestPropertyUnchangedAllocations\|TestDispatchAllocations\|TestConfigureFlushAllocations\|TestFocusAllocations\|TestSpaceAllocations\|TestUnmanagedGeometryAllocations\|TestFocusInUnmanagedAllocations\|TestUnmanagedPublishAllocations\|TestUnmanagedHitAllocations\|TestOverrideMovedUnchangedAllocations\|TestFullscreenConfigureAllocations\|TestKeyboardGrabSyncAllocations\|TestSelectionCopyAllocations\|TestSelectionINCRChunkAllocations)$$' -count=1
74	74		CGO_ENABLED=0 go test -tags xturbo_poison ./internal/adapters/wayland/xwm -count=1
75	75		check: vet test arch fakes-check log-check perf-check
76	76


@@ -70,7 +70,7 @@ adapter-imports:
70		[ -z "$$bad" ] \|\| { echo "$$bad"; echo 'adapter imports another adapter: use ports or a shared library (Makefile ADAPTER_LIBS)' >&2; exit 1; }	70		[ -z "$$bad" ] \|\| { echo "$$bad"; echo 'adapter imports another adapter: use ports or a shared library (Makefile ADAPTER_LIBS)' >&2; exit 1; }
71		# Fast, mandatory guards for tiled content publications and SHM copies.	71		# Fast, mandatory guards for tiled content publications and SHM copies.
72		perf-check:	72		perf-check:
73	-	CGO_ENABLED=0 go test ./internal/core ./internal/app ./internal/adapters/drm ./internal/adapters/headless ./internal/adapters/vulkan ./internal/adapters/wayland ./internal/adapters/outputkit/capture ./internal/adapters/screencast ./internal/adapters/wayland/xwm -run '^(TestAnimateAllocations\|TestPublishAllocations\|TestPublishSubscribersAllocations\|TestPublishStashSlideAllocations\|TestPublishOverviewAllocations\|TestPublishLeavingAllocations\|TestOutputRoutingAllocations\|TestReportSeenAllocations\|TestFrameLifecycleTransitionsAllocations\|TestFullscreenShownAllocations\|TestFrameDecisionAllocations\|TestCommitFrameAllocations\|TestColorPipelineAllocations\|TestShownBySnapshotAllocations\|TestFlipShowsAllocations\|TestMRUNoteFocusDoesNotAllocateWhenSettled\|TestDueFramesAllocations\|TestRenderSteadyStateAllocations\|TestRenderSteadyStateDMABufAllocations\|TestSceneOpaqueRegionAllocations\|TestSceneDeltaAllocations\|TestAccountFlipAllocations\|TestFlipDoneAllocations\|TestSceneWalkUnchangedTiledSHM\|TestTiledCommitPublishAllocations\|TestCapturedCommitApplyAllocations\|TestCapturedViewportApplyAllocations\|TestEffectiveInputEmptyTreeAllocations\|TestHeadlessTiledSHMCallbackAndCopyBudget\|TestReleaseHeldAllocations\|TestCommitDamageAllocations\|TestEmitContentAllocations\|TestPresentationPushAllocations\|TestAnimatingFrameSendAllocations\|TestContentBatchCycleAllocations\|TestWriteMappedAllocations\|TestCapturedForwardAllocations\|TestCommandForwardAllocations\|TestOutboxQueuedDeliveryAllocations\|TestCastFrameAllocations\|TestCastProducerAllocations\|TestCaptureCycleAllocations\|TestLogScenesAllocations\|TestOverviewNamedRowsAllocations\|TestBufferContentAllocations\|TestDueFramesFireScratch\|TestRetireSemaphoreAllocatesNothing\|TestTableLookupAllocations\|TestTableInsertRemoveAllocations\|TestPropertyUnchangedAllocations\|TestDispatchAllocations\|TestConfigureFlushAllocations\|TestFocusAllocations\|TestSpaceAllocations\|TestUnmanagedGeometryAllocations\|TestFocusInUnmanagedAllocations\|TestUnmanagedPublishAllocations\|TestUnmanagedHitAllocations\|TestOverrideMovedUnchangedAllocations\|TestFullscreenConfigureAllocations\|TestKeyboardGrabSyncAllocations)$$' -count=1	73	+	CGO_ENABLED=0 go test ./internal/core ./internal/app ./internal/adapters/drm ./internal/adapters/headless ./internal/adapters/vulkan ./internal/adapters/wayland ./internal/adapters/outputkit/capture ./internal/adapters/screencast ./internal/adapters/wayland/xwm -run '^(TestAnimateAllocations\|TestPublishAllocations\|TestPublishSubscribersAllocations\|TestPublishStashSlideAllocations\|TestPublishOverviewAllocations\|TestPublishLeavingAllocations\|TestOutputRoutingAllocations\|TestReportSeenAllocations\|TestFrameLifecycleTransitionsAllocations\|TestFullscreenShownAllocations\|TestFrameDecisionAllocations\|TestCommitFrameAllocations\|TestColorPipelineAllocations\|TestShownBySnapshotAllocations\|TestFlipShowsAllocations\|TestMRUNoteFocusDoesNotAllocateWhenSettled\|TestDueFramesAllocations\|TestRenderSteadyStateAllocations\|TestRenderSteadyStateDMABufAllocations\|TestSceneOpaqueRegionAllocations\|TestSceneDeltaAllocations\|TestAccountFlipAllocations\|TestFlipDoneAllocations\|TestSceneWalkUnchangedTiledSHM\|TestTiledCommitPublishAllocations\|TestCapturedCommitApplyAllocations\|TestCapturedViewportApplyAllocations\|TestEffectiveInputEmptyTreeAllocations\|TestHeadlessTiledSHMCallbackAndCopyBudget\|TestReleaseHeldAllocations\|TestCommitDamageAllocations\|TestEmitContentAllocations\|TestPresentationPushAllocations\|TestAnimatingFrameSendAllocations\|TestContentBatchCycleAllocations\|TestWriteMappedAllocations\|TestCapturedForwardAllocations\|TestCommandForwardAllocations\|TestOutboxQueuedDeliveryAllocations\|TestCastFrameAllocations\|TestCastProducerAllocations\|TestCaptureCycleAllocations\|TestLogScenesAllocations\|TestOverviewNamedRowsAllocations\|TestBufferContentAllocations\|TestDueFramesFireScratch\|TestRetireSemaphoreAllocatesNothing\|TestTableLookupAllocations\|TestTableInsertRemoveAllocations\|TestPropertyUnchangedAllocations\|TestDispatchAllocations\|TestConfigureFlushAllocations\|TestFocusAllocations\|TestSpaceAllocations\|TestUnmanagedGeometryAllocations\|TestFocusInUnmanagedAllocations\|TestUnmanagedPublishAllocations\|TestUnmanagedHitAllocations\|TestOverrideMovedUnchangedAllocations\|TestFullscreenConfigureAllocations\|TestKeyboardGrabSyncAllocations\|TestSelectionCopyAllocations\|TestSelectionINCRChunkAllocations)$$' -count=1
74		CGO_ENABLED=0 go test -tags xturbo_poison ./internal/adapters/wayland/xwm -count=1	74		CGO_ENABLED=0 go test -tags xturbo_poison ./internal/adapters/wayland/xwm -count=1
75		check: vet test arch fakes-check log-check perf-check	75		check: vet test arch fakes-check log-check perf-check
76			76

M internal/adapters/wayland/xwm/props.go +4 -0


@@ -113,6 +113,10 @@ func (x *XWM) requestProp(s Slot, idx int) {
113	113		// being mapped or is mapped; unwatched atoms cost nothing.
114	114		func (x XWM) onPropertyNotify(ev xturbo.Event) {
115	115		e := xproto.PropertyNotifyOf(ev)
	116	+	if uint32(e.Window()) == x.selWin && x.selWin != 0 {
	117	+	x.onSelProperty(ev)
	118	+	return
	119	+	}
116	120		s := x.tab.lookup(uint32(e.Window()))
117	121		if s == 0 {
118	122		return


@@ -113,6 +113,10 @@ func (x *XWM) requestProp(s Slot, idx int) {
113	// being mapped or is mapped; unwatched atoms cost nothing.	113		// being mapped or is mapped; unwatched atoms cost nothing.
114	func (x XWM) onPropertyNotify(ev xturbo.Event) {	114		func (x XWM) onPropertyNotify(ev xturbo.Event) {
115	e := xproto.PropertyNotifyOf(ev)	115		e := xproto.PropertyNotifyOf(ev)
		116	+	if uint32(e.Window()) == x.selWin && x.selWin != 0 {
		117	+	x.onSelProperty(ev)
		118	+	return
		119	+	}
116	s := x.tab.lookup(uint32(e.Window()))	120		s := x.tab.lookup(uint32(e.Window()))
117	if s == 0 {	121		if s == 0 {
118	return	122		return

M internal/adapters/wayland/xwm/selection.go +429 -3


@@ -2,10 +2,13 @@ package xwm
2	2
3	3		import (
4	4		"encoding/binary"
	5	+	"errors"
	6	+	"time"
5	7
6	8		"bnema.dev/xturbo"
7	9		"bnema.dev/xturbo/xfixes"
8	10		"bnema.dev/xturbo/xproto"
	11	+	"golang.org/x/sys/unix"
9	12		)
10	13
11	14		// The selection bridge: text-only CLIPBOARD and PRIMARY between X clients and

@@ -32,10 +35,99 @@ type selState struct {
32	35		owner uint32 // X owner window other than selWin, 0 none
33	36		}
34	37
	38	+	const (
	39	+	chunk = 65536 // every transfer step moves at most this many bytes
	40	+	nXfer = 4 // concurrent transfers per direction, and pool buffers
	41	+	tickEvery = time.Second
	42	+	xIdleMax = 10 // ticks without X-side progress
	43	+	rIdleMax = 30 // ticks of a reader that does not drain its pipe
	44	+	)
	45	+
	46	+	// bufPool is the fixed set of transfer buffers.
	47	+	type bufPool struct {
	48	+	bufs [nXfer][chunk]byte
	49	+	free [nXfer]int8
	50	+	n int
	51	+	}
	52	+
	53	+	func (p *bufPool) init() {
	54	+	for i := range p.free {
	55	+	p.free[i] = int8(i)
	56	+	}
	57	+	p.n = nXfer
	58	+	}
	59	+
	60	+	// get returns a free buffer index, -1 when the pool is exhausted.
	61	+	func (p *bufPool) get() int {
	62	+	if p.n == 0 {
	63	+	return -1
	64	+	}
	65	+	p.n--
	66	+	return int(p.free[p.n])
	67	+	}
	68	+
	69	+	func (p *bufPool) put(i int) {
	70	+	p.free[p.n] = int8(i)
	71	+	p.n++
	72	+	}
	73	+
	74	+	// X -> Wayland transfer states.
	75	+	const (
	76	+	inFree uint8 = iota
	77	+	inQueued // waiting for the conversion property to be free
	78	+	inConverting
	79	+	inWaitIncr // waiting for the next INCR chunk (PropertyNotify)
	80	+	inWriting // a buffer is pending on the Wayland reader's pipe
	81	+	inReading // a GetProperty is outstanding
	82	+	)
	83	+
	84	+	// xin is one X -> Wayland transfer.
	85	+	type xin struct {
	86	+	x *XWM
	87	+	idx int
	88	+	state uint8
	89	+	kind int
	90	+	fd int
	91	+	target uint32
	92	+	order uint64
	93	+	gen uint32 // stales replies of an aborted transfer
	94	+	incr bool
	95	+	buf int
	96	+	off, n int
	97	+	words uint32 // long offset of the next piece of a long property
	98	+	more bool // the last piece left bytes in the property
	99	+	ready bool // the owner wrote the next INCR chunk while a buffer was pending
	100	+	idle int
	101	+	src fdSource
	102	+	onR func() // pipe hangup
	103	+	onW func() // pipe writable
	104	+	}
	105	+
35	106		// selBridge is the XWM's selection state.
36	107		type selBridge struct {
37	108		st [selKinds]selState
38	109		mimes [len(textMimes)]string // scratch handed to SelectionOwned
	110	+	pool bufPool
	111	+	in [nXfer]xin
	112	+	order uint64
	113	+	// active is the transfer that owns the conversion property, -1 none.
	114	+	active int
	115	+	timerOn bool
	116	+	cancel func()
	117	+	tickFn func()
	118	+	}
	119	+
	120	+	func (x *XWM) initSelection() {
	121	+	b := &x.sel
	122	+	b.pool.init()
	123	+	b.active = -1
	124	+	b.tickFn = x.selTick
	125	+	for i := range b.in {
	126	+	t := &b.in[i]
	127	+	t.x, t.idx, t.buf = x, i, -1
	128	+	t.onR = func() { t.x.inAbort(t.idx, true) }
	129	+	t.onW = func() { t.x.inWritable(t.idx) }
	130	+	}
39	131		}
40	132
41	133		// bootSelection creates the selection window and asks for ownership events.

@@ -116,7 +208,11 @@ func (x XWM) onSelectionNotify(ev xturbo.Event) {
116	208		if k < 0 {
117	209		return
118	210		}
119		-	if uint32(e.Target()) == x.atoms[atomTargets] {
	211	+	if uint32(e.Target()) != x.atoms[atomTargets] {
	212	+	x.onDataNotify(e)
	213	+	return
	214	+	}
	215	+	{
120	216		if e.Property() == 0 {
121	217		if x.sel.st[k].owner != 0 {
122	218		x.host.SelectionOwned(k, nil)

@@ -167,7 +263,337 @@ func (x XWM) onTargetsReply(r xturbo.Reply) {
167	263		x.host.SelectionOwned(k, x.sel.mimes[:n])
168	264		}
169	265
	266	+	// ---- X -> Wayland ----
	267	+
	268	+	// SelectionReceive: a Wayland reader wants the X selection kind as mime. The
	269	+	// XWM takes fd (a write end it now owns) and closes it when done.
	270	+	func (x *XWM) SelectionReceive(kind int, mime string, fd int) {
	271	+	target := uint32(0)
	272	+	for i, m := range textMimes {
	273	+	if m == mime {
	274	+	target = x.atoms[mimeTarget[i]]
	275	+	break
	276	+	}
	277	+	}
	278	+	if x.selWin == 0 \|\| x.closed \|\| kind < 0 \|\| kind >= selKinds \|\| target == 0 \|\| x.sel.st[kind].owner == 0 {
	279	+	_ = unix.Close(fd)
	280	+	return
	281	+	}
	282	+	if unix.SetNonblock(fd, true) != nil {
	283	+	_ = unix.Close(fd)
	284	+	return
	285	+	}
	286	+	for i := range x.sel.in {
	287	+	t := &x.sel.in[i]
	288	+	if t.state != inFree {
	289	+	continue
	290	+	}
	291	+	x.sel.order++
	292	+	t.state, t.kind, t.fd, t.target, t.order = inQueued, kind, fd, target, x.sel.order
	293	+	t.incr, t.buf, t.off, t.n, t.words, t.more, t.ready, t.idle, t.src = false, -1, 0, 0, 0, false, false, 0, nil
	294	+	x.selEnsureTimer()
	295	+	x.inStartNext()
	296	+	return
	297	+	}
	298	+	x.log.Warn().Msg("selection: too many transfers, paste refused")
	299	+	_ = unix.Close(fd)
	300	+	}
	301	+
	302	+	// inStartNext starts the oldest queued transfer when none is converting.
	303	+	func (x *XWM) inStartNext() {
	304	+	b := &x.sel
	305	+	if b.active >= 0 {
	306	+	return
	307	+	}
	308	+	best := -1
	309	+	for i := range b.in {
	310	+	if b.in[i].state == inQueued && (best < 0 \|\| b.in[i].order < b.in[best].order) {
	311	+	best = i
	312	+	}
	313	+	}
	314	+	if best < 0 {
	315	+	return
	316	+	}
	317	+	t := &b.in[best]
	318	+	t.state, t.idle = inConverting, 0
	319	+	b.active = best
	320	+	xproto.ConvertSelection(x.conn.Buf(), xproto.Window(x.selWin), xproto.Atom(b.st[t.kind].atom),
	321	+	xproto.Atom(t.target), xproto.Atom(x.atoms[atomNeferwlData]), 0)
	322	+	x.wake()
	323	+	}
	324	+
	325	+	// inFinish ends transfer i and starts the next one.
	326	+	func (x *XWM) inFinish(i int) {
	327	+	b := &x.sel
	328	+	t := &b.in[i]
	329	+	if t.src != nil {
	330	+	t.src.Remove()
	331	+	t.src = nil
	332	+	}
	333	+	if t.fd >= 0 {
	334	+	_ = unix.Close(t.fd)
	335	+	}
	336	+	if t.buf >= 0 {
	337	+	b.pool.put(t.buf)
	338	+	t.buf = -1
	339	+	}
	340	+	t.gen++
	341	+	t.state, t.fd = inFree, -1
	342	+	if b.active == i {
	343	+	b.active = -1
	344	+	}
	345	+	x.inStartNext()
	346	+	}
	347	+
	348	+	// inAbort drops transfer i, deleting the conversion property when X may still
	349	+	// be writing it.
	350	+	func (x *XWM) inAbort(i int, del bool) {
	351	+	t := &x.sel.in[i]
	352	+	if t.state == inFree {
	353	+	return
	354	+	}
	355	+	if del && x.sel.active == i && !x.closed {
	356	+	xproto.DeleteProperty(x.conn.Buf(), xproto.Window(x.selWin), xproto.Atom(x.atoms[atomNeferwlData]))
	357	+	x.wake()
	358	+	}
	359	+	x.inFinish(i)
	360	+	}
	361	+
	362	+	// onDataNotify: the owner answered our data ConvertSelection.
	363	+	func (x *XWM) onDataNotify(e xproto.SelectionNotifyEvent) {
	364	+	i := x.sel.active
	365	+	if i < 0 {
	366	+	return
	367	+	}
	368	+	t := &x.sel.in[i]
	369	+	if t.state != inConverting \|\| uint32(e.Target()) != t.target {
	370	+	return
	371	+	}
	372	+	if e.Property() == 0 {
	373	+	x.inFinish(i)
	374	+	return
	375	+	}
	376	+	t.words = 0
	377	+	x.inRequest(i)
	378	+	}
	379	+
	380	+	// inRequest asks for the next piece of the property; delete makes INCR and
	381	+	// whole-value reads advance.
	382	+	func (x *XWM) inRequest(i int) {
	383	+	t := &x.sel.in[i]
	384	+	t.state = inReading
	385	+	seq := xproto.GetProperty(x.conn.Buf(), true, xproto.Window(x.selWin), xproto.Atom(x.atoms[atomNeferwlData]),
	386	+	0, t.words, chunk/4)
	387	+	if seq != 0 {
	388	+	if err := x.conn.Expect(seq, kindSelData, uint32(i), t.gen, 0, 0); err != nil {
	389	+	x.stats.RingFull++
	390	+	}
	391	+	}
	392	+	x.wake()
	393	+	}
	394	+
	395	+	// onSelDataReply handles one piece of the converted property.
	396	+	func (x XWM) onSelDataReply(r xturbo.Reply) {
	397	+	i := int(r.Args[0])
	398	+	if i < 0 \|\| i >= nXfer {
	399	+	return
	400	+	}
	401	+	t := &x.sel.in[i]
	402	+	if t.state != inReading \|\| t.gen != r.Args[1] {
	403	+	return
	404	+	}
	405	+	g, ok := xproto.ParseGetPropertyReply(r.Raw)
	406	+	if !ok \|\| g.Format() == 0 {
	407	+	x.inAbort(i, false)
	408	+	return
	409	+	}
	410	+	t.idle = 0
	411	+	if uint32(g.Type()) == x.atoms[atomIncr] {
	412	+	t.incr, t.state, t.words, t.more = true, inWaitIncr, 0, false
	413	+	return
	414	+	}
	415	+	v := g.Value()
	416	+	if g.Format() != 8 \|\| len(v) > chunk {
	417	+	x.inAbort(i, true)
	418	+	return
	419	+	}
	420	+	t.more = g.BytesAfter() > 0
	421	+	if len(v) == 0 {
	422	+	if t.more { // cannot happen: bytes remain only after a non-empty read
	423	+	x.inAbort(i, true)
	424	+	return
	425	+	}
	426	+	x.inNext(i)
	427	+	return
	428	+	}
	429	+	b := x.sel.pool.get()
	430	+	if b < 0 {
	431	+	x.log.Warn().Msg("selection: no free buffer, paste aborted")
	432	+	x.inAbort(i, true)
	433	+	return
	434	+	}
	435	+	t.buf = b
	436	+	t.n = copy(x.sel.pool.bufs[b][:], v)
	437	+	t.off = 0
	438	+	t.words += uint32(t.n) / 4
	439	+	t.state = inWriting
	440	+	x.inDrain(i)
	441	+	}
	442	+
	443	+	// inDrain writes the pending buffer to the reader's pipe.
	444	+	func (x *XWM) inDrain(i int) {
	445	+	t := &x.sel.in[i]
	446	+	buf := &x.sel.pool.bufs[t.buf]
	447	+	for t.off < t.n {
	448	+	n, err := unix.Write(t.fd, buf[t.off:t.n])
	449	+	switch {
	450	+	case err == nil:
	451	+	t.off += n
	452	+	t.idle = 0
	453	+	case errors.Is(err, unix.EINTR):
	454	+	case errors.Is(err, unix.EAGAIN):
	455	+	x.inWatch(i, true)
	456	+	return
	457	+	default: // EPIPE: the reader went away
	458	+	x.inAbort(i, true)
	459	+	return
	460	+	}
	461	+	}
	462	+	x.sel.pool.put(t.buf)
	463	+	t.buf = -1
	464	+	if t.src != nil {
	465	+	x.inWatch(i, false)
	466	+	}
	467	+	x.inNext(i)
	468	+	}
	469	+
	470	+	// inWatch arms or disarms writable interest on the reader's pipe.
	471	+	func (x *XWM) inWatch(i int, on bool) {
	472	+	t := &x.sel.in[i]
	473	+	if t.src == nil {
	474	+	if !on \|\| x.addFD == nil {
	475	+	if on {
	476	+	x.inAbort(i, true)
	477	+	}
	478	+	return
	479	+	}
	480	+	src, err := x.addFD(t.fd, t.onR, t.onW)
	481	+	if err != nil {
	482	+	x.inAbort(i, true)
	483	+	return
	484	+	}
	485	+	t.src = src
	486	+	}
	487	+	if err := t.src.SetWritable(on); err != nil {
	488	+	x.inAbort(i, true)
	489	+	}
	490	+	}
	491	+
	492	+	// inWritable: the pipe has room again.
	493	+	func (x *XWM) inWritable(i int) {
	494	+	t := &x.sel.in[i]
	495	+	if t.state == inWriting && t.buf >= 0 {
	496	+	x.inDrain(i)
	497	+	}
	498	+	}
	499	+
	500	+	// inNext decides what follows a drained (or empty) piece.
	501	+	func (x *XWM) inNext(i int) {
	502	+	t := &x.sel.in[i]
	503	+	switch {
	504	+	case t.more: // the rest of this property
	505	+	x.inRequest(i)
	506	+	case t.incr && t.n > 0:
	507	+	t.state, t.n, t.words = inWaitIncr, 0, 0
	508	+	if t.ready {
	509	+	t.ready = false
	510	+	x.inRequest(i)
	511	+	}
	512	+	default: // single value done, or the empty INCR terminator
	513	+	x.inFinish(i)
	514	+	}
	515	+	}
	516	+
	517	+	// onSelProperty: PropertyNotify on the selection window.
	518	+	func (x XWM) onSelProperty(ev xturbo.Event) {
	519	+	e := xproto.PropertyNotifyOf(ev)
	520	+	if e.State() != xproto.PropertyNewValue \|\| uint32(e.Atom()) != x.atoms[atomNeferwlData] {
	521	+	return
	522	+	}
	523	+	i := x.sel.active
	524	+	if i < 0 \|\| !x.sel.in[i].incr {
	525	+	return
	526	+	}
	527	+	t := &x.sel.in[i]
	528	+	switch t.state {
	529	+	case inWaitIncr:
	530	+	t.idle = 0
	531	+	t.n = 0
	532	+	x.inRequest(i)
	533	+	case inWriting, inReading:
	534	+	t.ready = true // no request while a buffer is pending: backpressure
	535	+	}
	536	+	}
	537	+
170	538		// onSelError: a selection request failed; the awaited reply never comes.
171		-	func (x XWM) onSelError(e xturbo.XError) {}
	539	+	func (x XWM) onSelError(e xturbo.XError) {
	540	+	if e.Kind == kindSelData {
	541	+	if i := int(e.Args[0]); i >= 0 && i < nXfer && x.sel.in[i].gen == e.Args[1] && x.sel.in[i].state == inReading {
	542	+	x.inAbort(i, false)
	543	+	}
	544	+	}
	545	+	}
	546	+
	547	+	// ---- timeouts ----
172	548
173		-	func (x XWM) onSelDataReply(r xturbo.Reply) {}
	549	+	func (x *XWM) selEnsureTimer() {
	550	+	b := &x.sel
	551	+	if b.timerOn \|\| x.after == nil {
	552	+	return
	553	+	}
	554	+	b.timerOn = true
	555	+	b.cancel = x.after(tickEvery, b.tickFn)
	556	+	}
	557	+
	558	+	// selTick ages every transfer by one second and aborts the stalled ones.
	559	+	func (x *XWM) selTick() {
	560	+	b := &x.sel
	561	+	b.timerOn, b.cancel = false, nil
	562	+	if x.closed {
	563	+	return
	564	+	}
	565	+	live := false
	566	+	for i := range b.in {
	567	+	t := &b.in[i]
	568	+	if t.state == inFree {
	569	+	continue
	570	+	}
	571	+	t.idle++
	572	+	limit := xIdleMax
	573	+	if t.state == inWriting {
	574	+	limit = rIdleMax
	575	+	}
	576	+	if t.state != inQueued && t.idle >= limit {
	577	+	x.log.Warn().Int("kind", t.kind).Msg("selection: transfer timed out")
	578	+	x.inAbort(i, true)
	579	+	continue
	580	+	}
	581	+	live = true
	582	+	}
	583	+	if live {
	584	+	x.selEnsureTimer()
	585	+	}
	586	+	}
	587	+
	588	+	// selClose aborts every transfer.
	589	+	func (x *XWM) selClose() {
	590	+	for i := range x.sel.in {
	591	+	if x.sel.in[i].state != inFree {
	592	+	x.inAbort(i, false)
	593	+	}
	594	+	}
	595	+	if x.sel.cancel != nil {
	596	+	x.sel.cancel()
	597	+	x.sel.cancel = nil
	598	+	}
	599	+	}


@@ -2,10 +2,13 @@ package xwm
2			2
3		import (	3		import (
4		"encoding/binary"	4		"encoding/binary"
			5	+	"errors"
			6	+	"time"
5			7
6		"bnema.dev/xturbo"	8		"bnema.dev/xturbo"
7		"bnema.dev/xturbo/xfixes"	9		"bnema.dev/xturbo/xfixes"
8		"bnema.dev/xturbo/xproto"	10		"bnema.dev/xturbo/xproto"
			11	+	"golang.org/x/sys/unix"
9		)	12		)
10			13
11		// The selection bridge: text-only CLIPBOARD and PRIMARY between X clients and	14		// The selection bridge: text-only CLIPBOARD and PRIMARY between X clients and

@@ -32,10 +35,99 @@ type selState struct {
32		owner uint32 // X owner window other than selWin, 0 none	35		owner uint32 // X owner window other than selWin, 0 none
33		}	36		}
34			37
			38	+	const (
			39	+	chunk = 65536 // every transfer step moves at most this many bytes
			40	+	nXfer = 4 // concurrent transfers per direction, and pool buffers
			41	+	tickEvery = time.Second
			42	+	xIdleMax = 10 // ticks without X-side progress
			43	+	rIdleMax = 30 // ticks of a reader that does not drain its pipe
			44	+	)
			45	+
			46	+	// bufPool is the fixed set of transfer buffers.
			47	+	type bufPool struct {
			48	+	bufs [nXfer][chunk]byte
			49	+	free [nXfer]int8
			50	+	n int
			51	+	}
			52	+
			53	+	func (p *bufPool) init() {
			54	+	for i := range p.free {
			55	+	p.free[i] = int8(i)
			56	+	}
			57	+	p.n = nXfer
			58	+	}
			59	+
			60	+	// get returns a free buffer index, -1 when the pool is exhausted.
			61	+	func (p *bufPool) get() int {
			62	+	if p.n == 0 {
			63	+	return -1
			64	+	}
			65	+	p.n--
			66	+	return int(p.free[p.n])
			67	+	}
			68	+
			69	+	func (p *bufPool) put(i int) {
			70	+	p.free[p.n] = int8(i)
			71	+	p.n++
			72	+	}
			73	+
			74	+	// X -> Wayland transfer states.
			75	+	const (
			76	+	inFree uint8 = iota
			77	+	inQueued // waiting for the conversion property to be free
			78	+	inConverting
			79	+	inWaitIncr // waiting for the next INCR chunk (PropertyNotify)
			80	+	inWriting // a buffer is pending on the Wayland reader's pipe
			81	+	inReading // a GetProperty is outstanding
			82	+	)
			83	+
			84	+	// xin is one X -> Wayland transfer.
			85	+	type xin struct {
			86	+	x *XWM
			87	+	idx int
			88	+	state uint8
			89	+	kind int
			90	+	fd int
			91	+	target uint32
			92	+	order uint64
			93	+	gen uint32 // stales replies of an aborted transfer
			94	+	incr bool
			95	+	buf int
			96	+	off, n int
			97	+	words uint32 // long offset of the next piece of a long property
			98	+	more bool // the last piece left bytes in the property
			99	+	ready bool // the owner wrote the next INCR chunk while a buffer was pending
			100	+	idle int
			101	+	src fdSource
			102	+	onR func() // pipe hangup
			103	+	onW func() // pipe writable
			104	+	}
			105	+
35		// selBridge is the XWM's selection state.	106		// selBridge is the XWM's selection state.
36		type selBridge struct {	107		type selBridge struct {
37		st [selKinds]selState	108		st [selKinds]selState
38		mimes [len(textMimes)]string // scratch handed to SelectionOwned	109		mimes [len(textMimes)]string // scratch handed to SelectionOwned
			110	+	pool bufPool
			111	+	in [nXfer]xin
			112	+	order uint64
			113	+	// active is the transfer that owns the conversion property, -1 none.
			114	+	active int
			115	+	timerOn bool
			116	+	cancel func()
			117	+	tickFn func()
			118	+	}
			119	+
			120	+	func (x *XWM) initSelection() {
			121	+	b := &x.sel
			122	+	b.pool.init()
			123	+	b.active = -1
			124	+	b.tickFn = x.selTick
			125	+	for i := range b.in {
			126	+	t := &b.in[i]
			127	+	t.x, t.idx, t.buf = x, i, -1
			128	+	t.onR = func() { t.x.inAbort(t.idx, true) }
			129	+	t.onW = func() { t.x.inWritable(t.idx) }
			130	+	}
39		}	131		}
40			132
41		// bootSelection creates the selection window and asks for ownership events.	133		// bootSelection creates the selection window and asks for ownership events.

@@ -116,7 +208,11 @@ func (x XWM) onSelectionNotify(ev xturbo.Event) {
116		if k < 0 {	208		if k < 0 {
117		return	209		return
118		}	210		}
119	-	if uint32(e.Target()) == x.atoms[atomTargets] {	211	+	if uint32(e.Target()) != x.atoms[atomTargets] {
			212	+	x.onDataNotify(e)
			213	+	return
			214	+	}
			215	+	{
120		if e.Property() == 0 {	216		if e.Property() == 0 {
121		if x.sel.st[k].owner != 0 {	217		if x.sel.st[k].owner != 0 {
122		x.host.SelectionOwned(k, nil)	218		x.host.SelectionOwned(k, nil)

@@ -167,7 +263,337 @@ func (x XWM) onTargetsReply(r xturbo.Reply) {
167		x.host.SelectionOwned(k, x.sel.mimes[:n])	263		x.host.SelectionOwned(k, x.sel.mimes[:n])
168		}	264		}
169			265
			266	+	// ---- X -> Wayland ----
			267	+
			268	+	// SelectionReceive: a Wayland reader wants the X selection kind as mime. The
			269	+	// XWM takes fd (a write end it now owns) and closes it when done.
			270	+	func (x *XWM) SelectionReceive(kind int, mime string, fd int) {
			271	+	target := uint32(0)
			272	+	for i, m := range textMimes {
			273	+	if m == mime {
			274	+	target = x.atoms[mimeTarget[i]]
			275	+	break
			276	+	}
			277	+	}
			278	+	if x.selWin == 0 \|\| x.closed \|\| kind < 0 \|\| kind >= selKinds \|\| target == 0 \|\| x.sel.st[kind].owner == 0 {
			279	+	_ = unix.Close(fd)
			280	+	return
			281	+	}
			282	+	if unix.SetNonblock(fd, true) != nil {
			283	+	_ = unix.Close(fd)
			284	+	return
			285	+	}
			286	+	for i := range x.sel.in {
			287	+	t := &x.sel.in[i]
			288	+	if t.state != inFree {
			289	+	continue
			290	+	}
			291	+	x.sel.order++
			292	+	t.state, t.kind, t.fd, t.target, t.order = inQueued, kind, fd, target, x.sel.order
			293	+	t.incr, t.buf, t.off, t.n, t.words, t.more, t.ready, t.idle, t.src = false, -1, 0, 0, 0, false, false, 0, nil
			294	+	x.selEnsureTimer()
			295	+	x.inStartNext()
			296	+	return
			297	+	}
			298	+	x.log.Warn().Msg("selection: too many transfers, paste refused")
			299	+	_ = unix.Close(fd)
			300	+	}
			301	+
			302	+	// inStartNext starts the oldest queued transfer when none is converting.
			303	+	func (x *XWM) inStartNext() {
			304	+	b := &x.sel
			305	+	if b.active >= 0 {
			306	+	return
			307	+	}
			308	+	best := -1
			309	+	for i := range b.in {
			310	+	if b.in[i].state == inQueued && (best < 0 \|\| b.in[i].order < b.in[best].order) {
			311	+	best = i
			312	+	}
			313	+	}
			314	+	if best < 0 {
			315	+	return
			316	+	}
			317	+	t := &b.in[best]
			318	+	t.state, t.idle = inConverting, 0
			319	+	b.active = best
			320	+	xproto.ConvertSelection(x.conn.Buf(), xproto.Window(x.selWin), xproto.Atom(b.st[t.kind].atom),
			321	+	xproto.Atom(t.target), xproto.Atom(x.atoms[atomNeferwlData]), 0)
			322	+	x.wake()
			323	+	}
			324	+
			325	+	// inFinish ends transfer i and starts the next one.
			326	+	func (x *XWM) inFinish(i int) {
			327	+	b := &x.sel
			328	+	t := &b.in[i]
			329	+	if t.src != nil {
			330	+	t.src.Remove()
			331	+	t.src = nil
			332	+	}
			333	+	if t.fd >= 0 {
			334	+	_ = unix.Close(t.fd)
			335	+	}
			336	+	if t.buf >= 0 {
			337	+	b.pool.put(t.buf)
			338	+	t.buf = -1
			339	+	}
			340	+	t.gen++
			341	+	t.state, t.fd = inFree, -1
			342	+	if b.active == i {
			343	+	b.active = -1
			344	+	}
			345	+	x.inStartNext()
			346	+	}
			347	+
			348	+	// inAbort drops transfer i, deleting the conversion property when X may still
			349	+	// be writing it.
			350	+	func (x *XWM) inAbort(i int, del bool) {
			351	+	t := &x.sel.in[i]
			352	+	if t.state == inFree {
			353	+	return
			354	+	}
			355	+	if del && x.sel.active == i && !x.closed {
			356	+	xproto.DeleteProperty(x.conn.Buf(), xproto.Window(x.selWin), xproto.Atom(x.atoms[atomNeferwlData]))
			357	+	x.wake()
			358	+	}
			359	+	x.inFinish(i)
			360	+	}
			361	+
			362	+	// onDataNotify: the owner answered our data ConvertSelection.
			363	+	func (x *XWM) onDataNotify(e xproto.SelectionNotifyEvent) {
			364	+	i := x.sel.active
			365	+	if i < 0 {
			366	+	return
			367	+	}
			368	+	t := &x.sel.in[i]
			369	+	if t.state != inConverting \|\| uint32(e.Target()) != t.target {
			370	+	return
			371	+	}
			372	+	if e.Property() == 0 {
			373	+	x.inFinish(i)
			374	+	return
			375	+	}
			376	+	t.words = 0
			377	+	x.inRequest(i)
			378	+	}
			379	+
			380	+	// inRequest asks for the next piece of the property; delete makes INCR and
			381	+	// whole-value reads advance.
			382	+	func (x *XWM) inRequest(i int) {
			383	+	t := &x.sel.in[i]
			384	+	t.state = inReading
			385	+	seq := xproto.GetProperty(x.conn.Buf(), true, xproto.Window(x.selWin), xproto.Atom(x.atoms[atomNeferwlData]),
			386	+	0, t.words, chunk/4)
			387	+	if seq != 0 {
			388	+	if err := x.conn.Expect(seq, kindSelData, uint32(i), t.gen, 0, 0); err != nil {
			389	+	x.stats.RingFull++
			390	+	}
			391	+	}
			392	+	x.wake()
			393	+	}
			394	+
			395	+	// onSelDataReply handles one piece of the converted property.
			396	+	func (x XWM) onSelDataReply(r xturbo.Reply) {
			397	+	i := int(r.Args[0])
			398	+	if i < 0 \|\| i >= nXfer {
			399	+	return
			400	+	}
			401	+	t := &x.sel.in[i]
			402	+	if t.state != inReading \|\| t.gen != r.Args[1] {
			403	+	return
			404	+	}
			405	+	g, ok := xproto.ParseGetPropertyReply(r.Raw)
			406	+	if !ok \|\| g.Format() == 0 {
			407	+	x.inAbort(i, false)
			408	+	return
			409	+	}
			410	+	t.idle = 0
			411	+	if uint32(g.Type()) == x.atoms[atomIncr] {
			412	+	t.incr, t.state, t.words, t.more = true, inWaitIncr, 0, false
			413	+	return
			414	+	}
			415	+	v := g.Value()
			416	+	if g.Format() != 8 \|\| len(v) > chunk {
			417	+	x.inAbort(i, true)
			418	+	return
			419	+	}
			420	+	t.more = g.BytesAfter() > 0
			421	+	if len(v) == 0 {
			422	+	if t.more { // cannot happen: bytes remain only after a non-empty read
			423	+	x.inAbort(i, true)
			424	+	return
			425	+	}
			426	+	x.inNext(i)
			427	+	return
			428	+	}
			429	+	b := x.sel.pool.get()
			430	+	if b < 0 {
			431	+	x.log.Warn().Msg("selection: no free buffer, paste aborted")
			432	+	x.inAbort(i, true)
			433	+	return
			434	+	}
			435	+	t.buf = b
			436	+	t.n = copy(x.sel.pool.bufs[b][:], v)
			437	+	t.off = 0
			438	+	t.words += uint32(t.n) / 4
			439	+	t.state = inWriting
			440	+	x.inDrain(i)
			441	+	}
			442	+
			443	+	// inDrain writes the pending buffer to the reader's pipe.
			444	+	func (x *XWM) inDrain(i int) {
			445	+	t := &x.sel.in[i]
			446	+	buf := &x.sel.pool.bufs[t.buf]
			447	+	for t.off < t.n {
			448	+	n, err := unix.Write(t.fd, buf[t.off:t.n])
			449	+	switch {
			450	+	case err == nil:
			451	+	t.off += n
			452	+	t.idle = 0
			453	+	case errors.Is(err, unix.EINTR):
			454	+	case errors.Is(err, unix.EAGAIN):
			455	+	x.inWatch(i, true)
			456	+	return
			457	+	default: // EPIPE: the reader went away
			458	+	x.inAbort(i, true)
			459	+	return
			460	+	}
			461	+	}
			462	+	x.sel.pool.put(t.buf)
			463	+	t.buf = -1
			464	+	if t.src != nil {
			465	+	x.inWatch(i, false)
			466	+	}
			467	+	x.inNext(i)
			468	+	}
			469	+
			470	+	// inWatch arms or disarms writable interest on the reader's pipe.
			471	+	func (x *XWM) inWatch(i int, on bool) {
			472	+	t := &x.sel.in[i]
			473	+	if t.src == nil {
			474	+	if !on \|\| x.addFD == nil {
			475	+	if on {
			476	+	x.inAbort(i, true)
			477	+	}
			478	+	return
			479	+	}
			480	+	src, err := x.addFD(t.fd, t.onR, t.onW)
			481	+	if err != nil {
			482	+	x.inAbort(i, true)
			483	+	return
			484	+	}
			485	+	t.src = src
			486	+	}
			487	+	if err := t.src.SetWritable(on); err != nil {
			488	+	x.inAbort(i, true)
			489	+	}
			490	+	}
			491	+
			492	+	// inWritable: the pipe has room again.
			493	+	func (x *XWM) inWritable(i int) {
			494	+	t := &x.sel.in[i]
			495	+	if t.state == inWriting && t.buf >= 0 {
			496	+	x.inDrain(i)
			497	+	}
			498	+	}
			499	+
			500	+	// inNext decides what follows a drained (or empty) piece.
			501	+	func (x *XWM) inNext(i int) {
			502	+	t := &x.sel.in[i]
			503	+	switch {
			504	+	case t.more: // the rest of this property
			505	+	x.inRequest(i)
			506	+	case t.incr && t.n > 0:
			507	+	t.state, t.n, t.words = inWaitIncr, 0, 0
			508	+	if t.ready {
			509	+	t.ready = false
			510	+	x.inRequest(i)
			511	+	}
			512	+	default: // single value done, or the empty INCR terminator
			513	+	x.inFinish(i)
			514	+	}
			515	+	}
			516	+
			517	+	// onSelProperty: PropertyNotify on the selection window.
			518	+	func (x XWM) onSelProperty(ev xturbo.Event) {
			519	+	e := xproto.PropertyNotifyOf(ev)
			520	+	if e.State() != xproto.PropertyNewValue \|\| uint32(e.Atom()) != x.atoms[atomNeferwlData] {
			521	+	return
			522	+	}
			523	+	i := x.sel.active
			524	+	if i < 0 \|\| !x.sel.in[i].incr {
			525	+	return
			526	+	}
			527	+	t := &x.sel.in[i]
			528	+	switch t.state {
			529	+	case inWaitIncr:
			530	+	t.idle = 0
			531	+	t.n = 0
			532	+	x.inRequest(i)
			533	+	case inWriting, inReading:
			534	+	t.ready = true // no request while a buffer is pending: backpressure
			535	+	}
			536	+	}
			537	+
170		// onSelError: a selection request failed; the awaited reply never comes.	538		// onSelError: a selection request failed; the awaited reply never comes.
171	-	func (x XWM) onSelError(e xturbo.XError) {}	539	+	func (x XWM) onSelError(e xturbo.XError) {
			540	+	if e.Kind == kindSelData {
			541	+	if i := int(e.Args[0]); i >= 0 && i < nXfer && x.sel.in[i].gen == e.Args[1] && x.sel.in[i].state == inReading {
			542	+	x.inAbort(i, false)
			543	+	}
			544	+	}
			545	+	}
			546	+
			547	+	// ---- timeouts ----
172			548
173	-	func (x XWM) onSelDataReply(r xturbo.Reply) {}	549	+	func (x *XWM) selEnsureTimer() {
			550	+	b := &x.sel
			551	+	if b.timerOn \|\| x.after == nil {
			552	+	return
			553	+	}
			554	+	b.timerOn = true
			555	+	b.cancel = x.after(tickEvery, b.tickFn)
			556	+	}
			557	+
			558	+	// selTick ages every transfer by one second and aborts the stalled ones.
			559	+	func (x *XWM) selTick() {
			560	+	b := &x.sel
			561	+	b.timerOn, b.cancel = false, nil
			562	+	if x.closed {
			563	+	return
			564	+	}
			565	+	live := false
			566	+	for i := range b.in {
			567	+	t := &b.in[i]
			568	+	if t.state == inFree {
			569	+	continue
			570	+	}
			571	+	t.idle++
			572	+	limit := xIdleMax
			573	+	if t.state == inWriting {
			574	+	limit = rIdleMax
			575	+	}
			576	+	if t.state != inQueued && t.idle >= limit {
			577	+	x.log.Warn().Int("kind", t.kind).Msg("selection: transfer timed out")
			578	+	x.inAbort(i, true)
			579	+	continue
			580	+	}
			581	+	live = true
			582	+	}
			583	+	if live {
			584	+	x.selEnsureTimer()
			585	+	}
			586	+	}
			587	+
			588	+	// selClose aborts every transfer.
			589	+	func (x *XWM) selClose() {
			590	+	for i := range x.sel.in {
			591	+	if x.sel.in[i].state != inFree {
			592	+	x.inAbort(i, false)
			593	+	}
			594	+	}
			595	+	if x.sel.cancel != nil {
			596	+	x.sel.cancel()
			597	+	x.sel.cancel = nil
			598	+	}
			599	+	}

M internal/adapters/wayland/xwm/selection_test.go +311 -0

@@ -1,10 +1,18 @@
1	1		package xwm
2	2
3	3		import (
	4	+	"bytes"
4	5		"encoding/binary"
	6	+	"io"
	7	+	"os"
5	8		"testing"
	9	+	"time"
6	10
	11	+	"bnema.dev/xturbo"
	12	+	"bnema.dev/xturbo/xproto"
	13	+	"github.com/stretchr/testify/mock"
7	14		"github.com/stretchr/testify/require"
	15	+	"golang.org/x/sys/unix"
8	16		)
9	17
10	18		const peerXFixesFirstEvent = 87

@@ -111,3 +119,306 @@ func TestSelectionXOwnsAnnounces(t *testing.T) {
111	119		x.flush()
112	120		require.Equal(t, before, len(p.requests()))
113	121		}
	122	+
	123	+	// ---- X -> Wayland ----
	124	+
	125	+	type selRig struct {
	126	+	x *XWM
	127	+	p *xpeer
	128	+	h *mockhost
	129	+	clip uint32
	130	+	utf8 uint32
	131	+	data uint32
	132	+	skip int
	133	+	timer func()
	134	+	}
	135	+
	136	+	// ownedRig attaches an XWM whose CLIPBOARD is owned by an X client offering text.
	137	+	func ownedRig(t testing.T) selRig {
	138	+	t.Helper()
	139	+	x, p, h, _, _ := attached(t)
	140	+	r := &selRig{x: x, p: p, h: h, clip: p.atom("CLIPBOARD"), utf8: p.atom("UTF8_STRING"), data: p.atom("_NEFERWL_DATA")}
	141	+	h.EXPECT().After(mock.Anything, mock.Anything).Run(func(_ time.Duration, fn func()) { r.timer = fn }).Return(func() {}).Maybe()
	142	+	got := 0
	143	+	h.EXPECT().SelectionOwned(SelClipboard, mock.Anything).Run(func(int, []string) { got++ }).Once()
	144	+	p.xfixesSelection(0x500010, r.clip)
	145	+	_, n := pumpReq(t, x, p, 0, func(q xpeerReq) bool { return q.major == 24 })
	146	+	tgt := p.atom("TARGETS")
	147	+	p.setProp(x.selWin, p.atom("_NEFERWL_TARGETS"), 4, 32, le32(tgt, r.utf8))
	148	+	p.selectionNotify(x.selWin, r.clip, tgt, p.atom("_NEFERWL_TARGETS"))
	149	+	readUntil(t, x, func() bool { return got == 1 })
	150	+	r.skip = len(p.requests())
	151	+	_ = n
	152	+	return r
	153	+	}
	154	+
	155	+	// receive starts a paste and returns the read end of its pipe.
	156	+	func (r selRig) receive(t testing.T, size int) *os.File {
	157	+	t.Helper()
	158	+	fds := make([]int, 2)
	159	+	require.NoError(t, unix.Pipe2(fds, unix.O_CLOEXEC))
	160	+	if size > 0 {
	161	+	_, err := unix.FcntlInt(uintptr(fds[0]), unix.F_SETPIPE_SZ, size)
	162	+	require.NoError(t, err)
	163	+	}
	164	+	r.x.SelectionReceive(SelClipboard, "text/plain;charset=utf-8", fds[1])
	165	+	r.x.flush()
	166	+	f := os.NewFile(uintptr(fds[0]), "pipe-r")
	167	+	t.Cleanup(func() { f.Close() })
	168	+	return f
	169	+	}
	170	+
	171	+	func (r selRig) waitGet(t testing.T) {
	172	+	t.Helper()
	173	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == opGetProperty && q.u32(8) == r.data })
	174	+	r.skip = n
	175	+	}
	176	+
	177	+	func pattern(n int) []byte {
	178	+	b := make([]byte, n)
	179	+	for i := range b {
	180	+	b[i] = byte(i*7 + i/251)
	181	+	}
	182	+	return b
	183	+	}
	184	+
	185	+	func TestSelectionXToWaylandSmall(t *testing.T) {
	186	+	r := ownedRig(t)
	187	+	f := r.receive(t, 0)
	188	+	req, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
	189	+	require.Equal(t, r.x.selWin, req.u32(4))
	190	+	require.Equal(t, r.clip, req.u32(8))
	191	+	require.Equal(t, r.utf8, req.u32(12))
	192	+	require.Equal(t, r.data, req.u32(16))
	193	+	r.skip = n
	194	+	r.p.setProp(r.x.selWin, r.data, r.utf8, 8, []byte("hello clipboard"))
	195	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, r.data)
	196	+	r.waitGet(t)
	197	+	buf := make([]byte, 64)
	198	+	var got []byte
	199	+	readUntil(t, r.x, func() bool {
	200	+	m, _ := unix.Read(int(f.Fd()), buf[:0:0])
	201	+	_ = m
	202	+	return r.x.sel.in[0].state == inFree
	203	+	})
	204	+	m, err := f.Read(buf)
	205	+	require.NoError(t, err)
	206	+	got = buf[:m]
	207	+	require.Equal(t, "hello clipboard", string(got))
	208	+	_, ok := r.p.prop(r.x.selWin, "_NEFERWL_DATA")
	209	+	require.False(t, ok, "property deleted by the read")
	210	+	_, err = f.Read(buf)
	211	+	require.ErrorIs(t, err, io.EOF, "write end closed")
	212	+	}
	213	+
	214	+	func TestSelectionXToWaylandRefused(t *testing.T) {
	215	+	r := ownedRig(t)
	216	+	f := r.receive(t, 0)
	217	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
	218	+	r.skip = n
	219	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, 0)
	220	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inFree })
	221	+	_, err := f.Read(make([]byte, 8))
	222	+	require.ErrorIs(t, err, io.EOF)
	223	+	}
	224	+
	225	+	func TestSelectionXToWaylandINCR(t *testing.T) {
	226	+	r := ownedRig(t)
	227	+	const total = 1 << 20
	228	+	want := pattern(total)
	229	+	f := r.receive(t, 1<<20)
	230	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
	231	+	r.skip = n
	232	+	r.p.setProp(r.x.selWin, r.data, r.p.atom("INCR"), 32, le32(total))
	233	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, r.data)
	234	+	r.waitGet(t) // reads and deletes the INCR marker
	235	+	gets := 1
	236	+	for off := 0; off <= total; off += chunk {
	237	+	end := min(off+chunk, total)
	238	+	r.p.setProp(r.x.selWin, r.data, r.utf8, 8, want[off:end])
	239	+	r.p.propertyNotify(r.x.selWin, r.data, false)
	240	+	r.waitGet(t)
	241	+	gets++
	242	+	}
	243	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inFree })
	244	+	got, err := io.ReadAll(f)
	245	+	require.NoError(t, err)
	246	+	require.True(t, bytes.Equal(want, got), "byte-exact, got %d", len(got))
	247	+	require.Equal(t, 1+total/chunk+1, gets, "marker, 16 chunks, empty terminator")
	248	+	}
	249	+
	250	+	// A reader that does not drain: no further GetProperty until the pipe has room.
	251	+	func TestSelectionXToWaylandBackpressure(t *testing.T) {
	252	+	r := ownedRig(t)
	253	+	src := newMockfdSource(t)
	254	+	var onW func()
	255	+	r.x.addFD = func(_ int, _, w func()) (fdSource, error) { onW = w; return src, nil }
	256	+	src.EXPECT().SetWritable(true).Return(nil).Once()
	257	+	src.EXPECT().SetWritable(false).Return(nil).Once()
	258	+	src.EXPECT().Remove().Return().Once()
	259	+	f := r.receive(t, 0) // default 64 KiB pipe
	260	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
	261	+	r.skip = n
	262	+	r.p.setProp(r.x.selWin, r.data, r.p.atom("INCR"), 32, le32(3*chunk))
	263	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, r.data)
	264	+	r.waitGet(t)
	265	+	want := pattern(3 * chunk)
	266	+	chunkN := func(k int) {
	267	+	r.p.setProp(r.x.selWin, r.data, r.utf8, 8, want[kchunk:(k+1)chunk])
	268	+	r.p.propertyNotify(r.x.selWin, r.data, false)
	269	+	}
	270	+	chunkN(0) // fills the pipe exactly
	271	+	r.waitGet(t)
	272	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inWaitIncr })
	273	+	chunkN(1) // nobody reads: EAGAIN, the buffer stays pending
	274	+	r.waitGet(t)
	275	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inWriting })
	276	+	require.NotNil(t, onW)
	277	+
	278	+	gets := getProps(r.p, 0, r.x.selWin)
	279	+	chunkN(2) // announced while a buffer is pending
	280	+	ev := r.x.Stats().Events
	281	+	readUntil(t, r.x, func() bool { return r.x.Stats().Events > ev })
	282	+	r.x.flush()
	283	+	require.Equal(t, gets, getProps(r.p, 0, r.x.selWin), "no GetProperty while a buffer is pending")
	284	+
	285	+	got := make([]byte, 0, 3*chunk)
	286	+	buf := make([]byte, chunk)
	287	+	m, err := f.Read(buf) // the reader wakes: room again
	288	+	require.NoError(t, err)
	289	+	got = append(got, buf[:m]...)
	290	+	onW()
	291	+	require.Equal(t, inReading, r.x.sel.in[0].state, "the pending announcement is served once drained")
	292	+	r.waitGet(t)
	293	+	_ = got
	294	+	r.x.selClose()
	295	+	}
	296	+
	297	+	func TestSelectionTimeouts(t *testing.T) {
	298	+	r := ownedRig(t)
	299	+	f := r.receive(t, 0)
	300	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
	301	+	r.skip = n
	302	+	require.NotNil(t, r.timer)
	303	+	// X stays silent after ConvertSelection: nine ticks keep it alive, the tenth aborts.
	304	+	for i := 0; i < xIdleMax-1; i++ {
	305	+	fn := r.timer
	306	+	fn()
	307	+	require.Equal(t, inConverting, r.x.sel.in[0].state, i)
	308	+	}
	309	+	r.timer()
	310	+	require.Equal(t, inFree, r.x.sel.in[0].state)
	311	+	_, err := f.Read(make([]byte, 8))
	312	+	require.ErrorIs(t, err, io.EOF, "fd closed")
	313	+	pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == opDeleteProperty && q.u32(8) == r.data })
	314	+	require.Equal(t, nXfer, r.x.sel.pool.n)
	315	+	}
	316	+
	317	+	func TestSelectionPoolExhausted(t *testing.T) {
	318	+	r := ownedRig(t)
	319	+	var files []*os.File
	320	+	for i := 0; i < nXfer; i++ {
	321	+	files = append(files, r.receive(t, 0))
	322	+	}
	323	+	fifth := r.receive(t, 0)
	324	+	_, err := fifth.Read(make([]byte, 8))
	325	+	require.ErrorIs(t, err, io.EOF, "the fifth paste is refused with its pipe closed")
	326	+	for i := range r.x.sel.in {
	327	+	require.NotEqual(t, inFree, r.x.sel.in[i].state, i)
	328	+	}
	329	+	_ = files
	330	+	r.x.selClose()
	331	+	for i := range r.x.sel.in {
	332	+	require.Equal(t, inFree, r.x.sel.in[i].state, i)
	333	+	}
	334	+	}
	335	+
	336	+	// allocRig is a rig whose peer sinks requests and whose timer seam is inert.
	337	+	func allocRig(t testing.T) selRig {
	338	+	r := ownedRig(t)
	339	+	sinkPeer(t, r.x, r.p)
	340	+	r.x.after = func(time.Duration, func()) func() { return func() {} }
	341	+	r.x.sel.timerOn = true // no timer re-arming in the measured loop
	342	+	return r
	343	+	}
	344	+
	345	+	func dataReply(r selRig, typ uint32, payload []byte) xturbo.Reply {
	346	+	raw := make([]byte, 32+(len(payload)+3)&^3)
	347	+	raw[0], raw[1] = 1, 8
	348	+	binary.LittleEndian.PutUint32(raw[8:], typ)
	349	+	binary.LittleEndian.PutUint32(raw[16:], uint32(len(payload)))
	350	+	copy(raw[32:], payload)
	351	+	return &xturbo.Reply{Kind: kindSelData, Raw: raw}
	352	+	}
	353	+
	354	+	func TestSelectionCopyAllocations(t *testing.T) {
	355	+	r := allocRig(t)
	356	+	x := r.x
	357	+	fds := make([]int, 2)
	358	+	require.NoError(t, unix.Pipe2(fds, unix.O_CLOEXEC))
	359	+	t.Cleanup(func() { unix.Close(fds[0]); unix.Close(fds[1]) })
	360	+	payload := pattern(4096)
	361	+	rep := dataReply(r, r.utf8, payload)
	362	+	var note xturbo.Event
	363	+	note.Kind = xproto.KindSelectionNotify
	364	+	binary.LittleEndian.PutUint32(note.Raw[8:], x.selWin)
	365	+	binary.LittleEndian.PutUint32(note.Raw[12:], r.clip)
	366	+	binary.LittleEndian.PutUint32(note.Raw[16:], r.utf8)
	367	+	binary.LittleEndian.PutUint32(note.Raw[20:], r.data)
	368	+	sink := make([]byte, 8192)
	369	+	mime := textMimes[0]
	370	+	round := func() {
	371	+	fd, err := unix.FcntlInt(uintptr(fds[1]), unix.F_DUPFD_CLOEXEC, 0)
	372	+	if err != nil {
	373	+	t.Fatal("dup")
	374	+	}
	375	+	x.SelectionReceive(SelClipboard, mime, fd)
	376	+	x.onSelectionNotify(&note)
	377	+	rep.Args = [4]uint32{0, x.sel.in[0].gen}
	378	+	x.onSelDataReply(rep)
	379	+	if m, err := unix.Read(fds[0], sink); err != nil \|\| m != 4096 {
	380	+	t.Fatal("read")
	381	+	}
	382	+	x.posted = false
	383	+	x.flush()
	384	+	}
	385	+	round()
	386	+	require.Zero(t, testing.AllocsPerRun(100, round))
	387	+	}
	388	+
	389	+	func TestSelectionINCRChunkAllocations(t *testing.T) {
	390	+	r := allocRig(t)
	391	+	x := r.x
	392	+	fds := make([]int, 2)
	393	+	require.NoError(t, unix.Pipe2(fds, unix.O_CLOEXEC))
	394	+	t.Cleanup(func() { unix.Close(fds[0]); unix.Close(fds[1]) })
	395	+	x.SelectionReceive(SelClipboard, textMimes[0], fds[1])
	396	+	var note xturbo.Event
	397	+	note.Kind = xproto.KindSelectionNotify
	398	+	binary.LittleEndian.PutUint32(note.Raw[8:], x.selWin)
	399	+	binary.LittleEndian.PutUint32(note.Raw[12:], r.clip)
	400	+	binary.LittleEndian.PutUint32(note.Raw[16:], r.utf8)
	401	+	binary.LittleEndian.PutUint32(note.Raw[20:], r.data)
	402	+	x.onSelectionNotify(&note)
	403	+	x.onSelDataReply(dataReply(r, r.p.atom("INCR"), le32(1<<20)))
	404	+	require.Equal(t, inWaitIncr, x.sel.in[0].state)
	405	+	rep := dataReply(r, r.utf8, pattern(chunk))
	406	+	var pn xturbo.Event
	407	+	pn.Kind = xproto.KindPropertyNotify
	408	+	binary.LittleEndian.PutUint32(pn.Raw[4:], x.selWin)
	409	+	binary.LittleEndian.PutUint32(pn.Raw[8:], r.data)
	410	+	sink := make([]byte, chunk)
	411	+	step := func() {
	412	+	x.onSelProperty(&pn)
	413	+	rep.Args = [4]uint32{0, x.sel.in[0].gen}
	414	+	x.onSelDataReply(rep)
	415	+	if m, err := unix.Read(fds[0], sink); err != nil \|\| m != chunk {
	416	+	t.Fatal("read")
	417	+	}
	418	+	x.posted = false
	419	+	x.flush()
	420	+	}
	421	+	step()
	422	+	require.Zero(t, testing.AllocsPerRun(100, step))
	423	+	require.Equal(t, inWaitIncr, x.sel.in[0].state)
	424	+	}

@@ -1,10 +1,18 @@
1	package xwm	1		package xwm
2		2
3	import (	3		import (
		4	+	"bytes"
4	"encoding/binary"	5		"encoding/binary"
		6	+	"io"
		7	+	"os"
5	"testing"	8		"testing"
		9	+	"time"
6		10
		11	+	"bnema.dev/xturbo"
		12	+	"bnema.dev/xturbo/xproto"
		13	+	"github.com/stretchr/testify/mock"
7	"github.com/stretchr/testify/require"	14		"github.com/stretchr/testify/require"
		15	+	"golang.org/x/sys/unix"
8	)	16		)
9		17
10	const peerXFixesFirstEvent = 87	18		const peerXFixesFirstEvent = 87

@@ -111,3 +119,306 @@ func TestSelectionXOwnsAnnounces(t *testing.T) {
111	x.flush()	119		x.flush()
112	require.Equal(t, before, len(p.requests()))	120		require.Equal(t, before, len(p.requests()))
113	}	121		}
		122	+
		123	+	// ---- X -> Wayland ----
		124	+
		125	+	type selRig struct {
		126	+	x *XWM
		127	+	p *xpeer
		128	+	h *mockhost
		129	+	clip uint32
		130	+	utf8 uint32
		131	+	data uint32
		132	+	skip int
		133	+	timer func()
		134	+	}
		135	+
		136	+	// ownedRig attaches an XWM whose CLIPBOARD is owned by an X client offering text.
		137	+	func ownedRig(t testing.T) selRig {
		138	+	t.Helper()
		139	+	x, p, h, _, _ := attached(t)
		140	+	r := &selRig{x: x, p: p, h: h, clip: p.atom("CLIPBOARD"), utf8: p.atom("UTF8_STRING"), data: p.atom("_NEFERWL_DATA")}
		141	+	h.EXPECT().After(mock.Anything, mock.Anything).Run(func(_ time.Duration, fn func()) { r.timer = fn }).Return(func() {}).Maybe()
		142	+	got := 0
		143	+	h.EXPECT().SelectionOwned(SelClipboard, mock.Anything).Run(func(int, []string) { got++ }).Once()
		144	+	p.xfixesSelection(0x500010, r.clip)
		145	+	_, n := pumpReq(t, x, p, 0, func(q xpeerReq) bool { return q.major == 24 })
		146	+	tgt := p.atom("TARGETS")
		147	+	p.setProp(x.selWin, p.atom("_NEFERWL_TARGETS"), 4, 32, le32(tgt, r.utf8))
		148	+	p.selectionNotify(x.selWin, r.clip, tgt, p.atom("_NEFERWL_TARGETS"))
		149	+	readUntil(t, x, func() bool { return got == 1 })
		150	+	r.skip = len(p.requests())
		151	+	_ = n
		152	+	return r
		153	+	}
		154	+
		155	+	// receive starts a paste and returns the read end of its pipe.
		156	+	func (r selRig) receive(t testing.T, size int) *os.File {
		157	+	t.Helper()
		158	+	fds := make([]int, 2)
		159	+	require.NoError(t, unix.Pipe2(fds, unix.O_CLOEXEC))
		160	+	if size > 0 {
		161	+	_, err := unix.FcntlInt(uintptr(fds[0]), unix.F_SETPIPE_SZ, size)
		162	+	require.NoError(t, err)
		163	+	}
		164	+	r.x.SelectionReceive(SelClipboard, "text/plain;charset=utf-8", fds[1])
		165	+	r.x.flush()
		166	+	f := os.NewFile(uintptr(fds[0]), "pipe-r")
		167	+	t.Cleanup(func() { f.Close() })
		168	+	return f
		169	+	}
		170	+
		171	+	func (r selRig) waitGet(t testing.T) {
		172	+	t.Helper()
		173	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == opGetProperty && q.u32(8) == r.data })
		174	+	r.skip = n
		175	+	}
		176	+
		177	+	func pattern(n int) []byte {
		178	+	b := make([]byte, n)
		179	+	for i := range b {
		180	+	b[i] = byte(i*7 + i/251)
		181	+	}
		182	+	return b
		183	+	}
		184	+
		185	+	func TestSelectionXToWaylandSmall(t *testing.T) {
		186	+	r := ownedRig(t)
		187	+	f := r.receive(t, 0)
		188	+	req, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
		189	+	require.Equal(t, r.x.selWin, req.u32(4))
		190	+	require.Equal(t, r.clip, req.u32(8))
		191	+	require.Equal(t, r.utf8, req.u32(12))
		192	+	require.Equal(t, r.data, req.u32(16))
		193	+	r.skip = n
		194	+	r.p.setProp(r.x.selWin, r.data, r.utf8, 8, []byte("hello clipboard"))
		195	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, r.data)
		196	+	r.waitGet(t)
		197	+	buf := make([]byte, 64)
		198	+	var got []byte
		199	+	readUntil(t, r.x, func() bool {
		200	+	m, _ := unix.Read(int(f.Fd()), buf[:0:0])
		201	+	_ = m
		202	+	return r.x.sel.in[0].state == inFree
		203	+	})
		204	+	m, err := f.Read(buf)
		205	+	require.NoError(t, err)
		206	+	got = buf[:m]
		207	+	require.Equal(t, "hello clipboard", string(got))
		208	+	_, ok := r.p.prop(r.x.selWin, "_NEFERWL_DATA")
		209	+	require.False(t, ok, "property deleted by the read")
		210	+	_, err = f.Read(buf)
		211	+	require.ErrorIs(t, err, io.EOF, "write end closed")
		212	+	}
		213	+
		214	+	func TestSelectionXToWaylandRefused(t *testing.T) {
		215	+	r := ownedRig(t)
		216	+	f := r.receive(t, 0)
		217	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
		218	+	r.skip = n
		219	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, 0)
		220	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inFree })
		221	+	_, err := f.Read(make([]byte, 8))
		222	+	require.ErrorIs(t, err, io.EOF)
		223	+	}
		224	+
		225	+	func TestSelectionXToWaylandINCR(t *testing.T) {
		226	+	r := ownedRig(t)
		227	+	const total = 1 << 20
		228	+	want := pattern(total)
		229	+	f := r.receive(t, 1<<20)
		230	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
		231	+	r.skip = n
		232	+	r.p.setProp(r.x.selWin, r.data, r.p.atom("INCR"), 32, le32(total))
		233	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, r.data)
		234	+	r.waitGet(t) // reads and deletes the INCR marker
		235	+	gets := 1
		236	+	for off := 0; off <= total; off += chunk {
		237	+	end := min(off+chunk, total)
		238	+	r.p.setProp(r.x.selWin, r.data, r.utf8, 8, want[off:end])
		239	+	r.p.propertyNotify(r.x.selWin, r.data, false)
		240	+	r.waitGet(t)
		241	+	gets++
		242	+	}
		243	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inFree })
		244	+	got, err := io.ReadAll(f)
		245	+	require.NoError(t, err)
		246	+	require.True(t, bytes.Equal(want, got), "byte-exact, got %d", len(got))
		247	+	require.Equal(t, 1+total/chunk+1, gets, "marker, 16 chunks, empty terminator")
		248	+	}
		249	+
		250	+	// A reader that does not drain: no further GetProperty until the pipe has room.
		251	+	func TestSelectionXToWaylandBackpressure(t *testing.T) {
		252	+	r := ownedRig(t)
		253	+	src := newMockfdSource(t)
		254	+	var onW func()
		255	+	r.x.addFD = func(_ int, _, w func()) (fdSource, error) { onW = w; return src, nil }
		256	+	src.EXPECT().SetWritable(true).Return(nil).Once()
		257	+	src.EXPECT().SetWritable(false).Return(nil).Once()
		258	+	src.EXPECT().Remove().Return().Once()
		259	+	f := r.receive(t, 0) // default 64 KiB pipe
		260	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
		261	+	r.skip = n
		262	+	r.p.setProp(r.x.selWin, r.data, r.p.atom("INCR"), 32, le32(3*chunk))
		263	+	r.p.selectionNotify(r.x.selWin, r.clip, r.utf8, r.data)
		264	+	r.waitGet(t)
		265	+	want := pattern(3 * chunk)
		266	+	chunkN := func(k int) {
		267	+	r.p.setProp(r.x.selWin, r.data, r.utf8, 8, want[kchunk:(k+1)chunk])
		268	+	r.p.propertyNotify(r.x.selWin, r.data, false)
		269	+	}
		270	+	chunkN(0) // fills the pipe exactly
		271	+	r.waitGet(t)
		272	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inWaitIncr })
		273	+	chunkN(1) // nobody reads: EAGAIN, the buffer stays pending
		274	+	r.waitGet(t)
		275	+	readUntil(t, r.x, func() bool { return r.x.sel.in[0].state == inWriting })
		276	+	require.NotNil(t, onW)
		277	+
		278	+	gets := getProps(r.p, 0, r.x.selWin)
		279	+	chunkN(2) // announced while a buffer is pending
		280	+	ev := r.x.Stats().Events
		281	+	readUntil(t, r.x, func() bool { return r.x.Stats().Events > ev })
		282	+	r.x.flush()
		283	+	require.Equal(t, gets, getProps(r.p, 0, r.x.selWin), "no GetProperty while a buffer is pending")
		284	+
		285	+	got := make([]byte, 0, 3*chunk)
		286	+	buf := make([]byte, chunk)
		287	+	m, err := f.Read(buf) // the reader wakes: room again
		288	+	require.NoError(t, err)
		289	+	got = append(got, buf[:m]...)
		290	+	onW()
		291	+	require.Equal(t, inReading, r.x.sel.in[0].state, "the pending announcement is served once drained")
		292	+	r.waitGet(t)
		293	+	_ = got
		294	+	r.x.selClose()
		295	+	}
		296	+
		297	+	func TestSelectionTimeouts(t *testing.T) {
		298	+	r := ownedRig(t)
		299	+	f := r.receive(t, 0)
		300	+	_, n := pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == 24 })
		301	+	r.skip = n
		302	+	require.NotNil(t, r.timer)
		303	+	// X stays silent after ConvertSelection: nine ticks keep it alive, the tenth aborts.
		304	+	for i := 0; i < xIdleMax-1; i++ {
		305	+	fn := r.timer
		306	+	fn()
		307	+	require.Equal(t, inConverting, r.x.sel.in[0].state, i)
		308	+	}
		309	+	r.timer()
		310	+	require.Equal(t, inFree, r.x.sel.in[0].state)
		311	+	_, err := f.Read(make([]byte, 8))
		312	+	require.ErrorIs(t, err, io.EOF, "fd closed")
		313	+	pumpReq(t, r.x, r.p, r.skip, func(q xpeerReq) bool { return q.major == opDeleteProperty && q.u32(8) == r.data })
		314	+	require.Equal(t, nXfer, r.x.sel.pool.n)
		315	+	}
		316	+
		317	+	func TestSelectionPoolExhausted(t *testing.T) {
		318	+	r := ownedRig(t)
		319	+	var files []*os.File
		320	+	for i := 0; i < nXfer; i++ {
		321	+	files = append(files, r.receive(t, 0))
		322	+	}
		323	+	fifth := r.receive(t, 0)
		324	+	_, err := fifth.Read(make([]byte, 8))
		325	+	require.ErrorIs(t, err, io.EOF, "the fifth paste is refused with its pipe closed")
		326	+	for i := range r.x.sel.in {
		327	+	require.NotEqual(t, inFree, r.x.sel.in[i].state, i)
		328	+	}
		329	+	_ = files
		330	+	r.x.selClose()
		331	+	for i := range r.x.sel.in {
		332	+	require.Equal(t, inFree, r.x.sel.in[i].state, i)
		333	+	}
		334	+	}
		335	+
		336	+	// allocRig is a rig whose peer sinks requests and whose timer seam is inert.
		337	+	func allocRig(t testing.T) selRig {
		338	+	r := ownedRig(t)
		339	+	sinkPeer(t, r.x, r.p)
		340	+	r.x.after = func(time.Duration, func()) func() { return func() {} }
		341	+	r.x.sel.timerOn = true // no timer re-arming in the measured loop
		342	+	return r
		343	+	}
		344	+
		345	+	func dataReply(r selRig, typ uint32, payload []byte) xturbo.Reply {
		346	+	raw := make([]byte, 32+(len(payload)+3)&^3)
		347	+	raw[0], raw[1] = 1, 8
		348	+	binary.LittleEndian.PutUint32(raw[8:], typ)
		349	+	binary.LittleEndian.PutUint32(raw[16:], uint32(len(payload)))
		350	+	copy(raw[32:], payload)
		351	+	return &xturbo.Reply{Kind: kindSelData, Raw: raw}
		352	+	}
		353	+
		354	+	func TestSelectionCopyAllocations(t *testing.T) {
		355	+	r := allocRig(t)
		356	+	x := r.x
		357	+	fds := make([]int, 2)
		358	+	require.NoError(t, unix.Pipe2(fds, unix.O_CLOEXEC))
		359	+	t.Cleanup(func() { unix.Close(fds[0]); unix.Close(fds[1]) })
		360	+	payload := pattern(4096)
		361	+	rep := dataReply(r, r.utf8, payload)
		362	+	var note xturbo.Event
		363	+	note.Kind = xproto.KindSelectionNotify
		364	+	binary.LittleEndian.PutUint32(note.Raw[8:], x.selWin)
		365	+	binary.LittleEndian.PutUint32(note.Raw[12:], r.clip)
		366	+	binary.LittleEndian.PutUint32(note.Raw[16:], r.utf8)
		367	+	binary.LittleEndian.PutUint32(note.Raw[20:], r.data)
		368	+	sink := make([]byte, 8192)
		369	+	mime := textMimes[0]
		370	+	round := func() {
		371	+	fd, err := unix.FcntlInt(uintptr(fds[1]), unix.F_DUPFD_CLOEXEC, 0)
		372	+	if err != nil {
		373	+	t.Fatal("dup")
		374	+	}
		375	+	x.SelectionReceive(SelClipboard, mime, fd)
		376	+	x.onSelectionNotify(&note)
		377	+	rep.Args = [4]uint32{0, x.sel.in[0].gen}
		378	+	x.onSelDataReply(rep)
		379	+	if m, err := unix.Read(fds[0], sink); err != nil \|\| m != 4096 {
		380	+	t.Fatal("read")
		381	+	}
		382	+	x.posted = false
		383	+	x.flush()
		384	+	}
		385	+	round()
		386	+	require.Zero(t, testing.AllocsPerRun(100, round))
		387	+	}
		388	+
		389	+	func TestSelectionINCRChunkAllocations(t *testing.T) {
		390	+	r := allocRig(t)
		391	+	x := r.x
		392	+	fds := make([]int, 2)
		393	+	require.NoError(t, unix.Pipe2(fds, unix.O_CLOEXEC))
		394	+	t.Cleanup(func() { unix.Close(fds[0]); unix.Close(fds[1]) })
		395	+	x.SelectionReceive(SelClipboard, textMimes[0], fds[1])
		396	+	var note xturbo.Event
		397	+	note.Kind = xproto.KindSelectionNotify
		398	+	binary.LittleEndian.PutUint32(note.Raw[8:], x.selWin)
		399	+	binary.LittleEndian.PutUint32(note.Raw[12:], r.clip)
		400	+	binary.LittleEndian.PutUint32(note.Raw[16:], r.utf8)
		401	+	binary.LittleEndian.PutUint32(note.Raw[20:], r.data)
		402	+	x.onSelectionNotify(&note)
		403	+	x.onSelDataReply(dataReply(r, r.p.atom("INCR"), le32(1<<20)))
		404	+	require.Equal(t, inWaitIncr, x.sel.in[0].state)
		405	+	rep := dataReply(r, r.utf8, pattern(chunk))
		406	+	var pn xturbo.Event
		407	+	pn.Kind = xproto.KindPropertyNotify
		408	+	binary.LittleEndian.PutUint32(pn.Raw[4:], x.selWin)
		409	+	binary.LittleEndian.PutUint32(pn.Raw[8:], r.data)
		410	+	sink := make([]byte, chunk)
		411	+	step := func() {
		412	+	x.onSelProperty(&pn)
		413	+	rep.Args = [4]uint32{0, x.sel.in[0].gen}
		414	+	x.onSelDataReply(rep)
		415	+	if m, err := unix.Read(fds[0], sink); err != nil \|\| m != chunk {
		416	+	t.Fatal("read")
		417	+	}
		418	+	x.posted = false
		419	+	x.flush()
		420	+	}
		421	+	step()
		422	+	require.Zero(t, testing.AllocsPerRun(100, step))
		423	+	require.Equal(t, inWaitIncr, x.sel.in[0].state)
		424	+	}

M internal/adapters/wayland/xwm/xpeer_test.go +16 -3


@@ -365,12 +365,25 @@ func (p *xpeer) answer(r xpeerReq, body []byte) {
365	365		delete(p.props[binary.LittleEndian.Uint32(body)], binary.LittleEndian.Uint32(body[4:]))
366	366		case r.major == opGetProperty:
367	367		win, prop := binary.LittleEndian.Uint32(body), binary.LittleEndian.Uint32(body[4:])
	368	+	off, length := int(binary.LittleEndian.Uint32(body[12:]))4, int(binary.LittleEndian.Uint32(body[16:]))4
368	369		v, ok := p.props[win][prop]
369		-	b := make([]byte, 24+(len(v.data)+3)&^3)
	370	+	data, after := v.data, 0
	371	+	if off > len(data) {
	372	+	off = len(data)
	373	+	}
	374	+	data = data[off:]
	375	+	if len(data) > length {
	376	+	data, after = data[:length], len(data)-length
	377	+	}
	378	+	b := make([]byte, 24+(len(data)+3)&^3)
370	379		if ok && v.format != 0 {
371	380		binary.LittleEndian.PutUint32(b[0:], v.typ)
372		-	binary.LittleEndian.PutUint32(b[8:], uint32(len(v.data)/(int(v.format)/8)))
373		-	copy(b[24:], v.data)
	381	+	binary.LittleEndian.PutUint32(b[4:], uint32(after))
	382	+	binary.LittleEndian.PutUint32(b[8:], uint32(len(data)/(int(v.format)/8)))
	383	+	copy(b[24:], data)
	384	+	if r.raw[1] != 0 && after == 0 { // delete
	385	+	delete(p.props[win], prop)
	386	+	}
374	387		}
375	388		p.reply(v.format, b)
376	389		case r.major == opChangeWindowAttributes:


@@ -365,12 +365,25 @@ func (p *xpeer) answer(r xpeerReq, body []byte) {
365		delete(p.props[binary.LittleEndian.Uint32(body)], binary.LittleEndian.Uint32(body[4:]))	365		delete(p.props[binary.LittleEndian.Uint32(body)], binary.LittleEndian.Uint32(body[4:]))
366		case r.major == opGetProperty:	366		case r.major == opGetProperty:
367		win, prop := binary.LittleEndian.Uint32(body), binary.LittleEndian.Uint32(body[4:])	367		win, prop := binary.LittleEndian.Uint32(body), binary.LittleEndian.Uint32(body[4:])
			368	+	off, length := int(binary.LittleEndian.Uint32(body[12:]))4, int(binary.LittleEndian.Uint32(body[16:]))4
368		v, ok := p.props[win][prop]	369		v, ok := p.props[win][prop]
369	-	b := make([]byte, 24+(len(v.data)+3)&^3)	370	+	data, after := v.data, 0
			371	+	if off > len(data) {
			372	+	off = len(data)
			373	+	}
			374	+	data = data[off:]
			375	+	if len(data) > length {
			376	+	data, after = data[:length], len(data)-length
			377	+	}
			378	+	b := make([]byte, 24+(len(data)+3)&^3)
370		if ok && v.format != 0 {	379		if ok && v.format != 0 {
371		binary.LittleEndian.PutUint32(b[0:], v.typ)	380		binary.LittleEndian.PutUint32(b[0:], v.typ)
372	-	binary.LittleEndian.PutUint32(b[8:], uint32(len(v.data)/(int(v.format)/8)))	381	+	binary.LittleEndian.PutUint32(b[4:], uint32(after))
373	-	copy(b[24:], v.data)	382	+	binary.LittleEndian.PutUint32(b[8:], uint32(len(data)/(int(v.format)/8)))
			383	+	copy(b[24:], data)
			384	+	if r.raw[1] != 0 && after == 0 { // delete
			385	+	delete(p.props[win], prop)
			386	+	}
374		}	387		}
375		p.reply(v.format, b)	388		p.reply(v.format, b)
376		case r.major == opChangeWindowAttributes:	389		case r.major == opChangeWindowAttributes:

M internal/adapters/wayland/xwm/xwm.go +13 -0


@@ -14,6 +14,7 @@ import (
14	14		"fmt"
15	15		"io"
16	16		"os"
	17	+	"time"
17	18
18	19		"bnema.dev/xturbo"
19	20		"bnema.dev/xturbo/composite"

@@ -63,6 +64,8 @@ type XWM struct {
63	64		// attachment
64	65		host host
65	66		src fdSource
	67	+	addFD func(fd int, onReadable, onWritable func()) (fdSource, error) // display fd source seam
	68	+	after func(d time.Duration, fn func()) (cancel func())
66	69		post func(func())
67	70		flushFn func()
68	71

@@ -92,6 +95,7 @@ func newXWM(conn xturbo.Conn, log zerowrap.Logger) XWM {
92	95		x := &XWM{conn: conn, log: log, root: conn.Root(), tab: newTable(initialSlots), space: new(Space)}
93	96		x.h = xturbo.Handler{OnEvent: x.onEvent, OnReply: x.onReply, OnError: x.onError}
94	97		x.fit()
	98	+	x.initSelection()
95	99		return x
96	100		}
97	101

@@ -312,6 +316,13 @@ func (x *XWM) boot() error {
312	316		// Attach registers the X socket with the display and hands the windows found
313	317		// at boot to h. Display goroutine only.
314	318		func (x XWM) Attach(d server.Display, h host) error {
	319	+	x.addFD = func(fd int, r, w func()) (fdSource, error) {
	320	+	s, err := d.AddFDRW(fd, r, w)
	321	+	if err != nil {
	322	+	return nil, err
	323	+	}
	324	+	return s, nil
	325	+	}
315	326		src, err := d.AddFDRW(x.conn.Fd(), x.onReadable, x.onWritable)
316	327		if err != nil {
317	328		return fmt.Errorf("xwm: watch X socket: %w", err)

@@ -323,6 +334,7 @@ func (x XWM) Attach(d server.Display, h host) error {
323	334		// attach is Attach over its seams: the event source and the display's Post.
324	335		func (x *XWM) attach(src fdSource, h host, post func(func())) {
325	336		x.src, x.host, x.post = src, h, post
	337	+	x.after = h.After
326	338		x.flushFn = func() {
327	339		x.posted = false
328	340		x.flush()

@@ -352,6 +364,7 @@ func (x *XWM) Close() {
352	364		return
353	365		}
354	366		x.closed = true
	367	+	x.selClose()
355	368		s := x.stats
356	369		x.log.Info().Uint64("events", s.Events).Uint64("replies", s.Replies).Uint64("errors", s.Errors).
357	370		Uint64("unattributed", s.Unattributed).Uint64("stale", s.Stale).Uint64("ring_full", s.RingFull).


@@ -14,6 +14,7 @@ import (
14	"fmt"	14		"fmt"
15	"io"	15		"io"
16	"os"	16		"os"
		17	+	"time"
17		18
18	"bnema.dev/xturbo"	19		"bnema.dev/xturbo"
19	"bnema.dev/xturbo/composite"	20		"bnema.dev/xturbo/composite"

@@ -63,6 +64,8 @@ type XWM struct {
63	// attachment	64		// attachment
64	host host	65		host host
65	src fdSource	66		src fdSource
		67	+	addFD func(fd int, onReadable, onWritable func()) (fdSource, error) // display fd source seam
		68	+	after func(d time.Duration, fn func()) (cancel func())
66	post func(func())	69		post func(func())
67	flushFn func()	70		flushFn func()
68		71

@@ -92,6 +95,7 @@ func newXWM(conn xturbo.Conn, log zerowrap.Logger) XWM {
92	x := &XWM{conn: conn, log: log, root: conn.Root(), tab: newTable(initialSlots), space: new(Space)}	95		x := &XWM{conn: conn, log: log, root: conn.Root(), tab: newTable(initialSlots), space: new(Space)}
93	x.h = xturbo.Handler{OnEvent: x.onEvent, OnReply: x.onReply, OnError: x.onError}	96		x.h = xturbo.Handler{OnEvent: x.onEvent, OnReply: x.onReply, OnError: x.onError}
94	x.fit()	97		x.fit()
		98	+	x.initSelection()
95	return x	99		return x
96	}	100		}
97		101

@@ -312,6 +316,13 @@ func (x *XWM) boot() error {
312	// Attach registers the X socket with the display and hands the windows found	316		// Attach registers the X socket with the display and hands the windows found
313	// at boot to h. Display goroutine only.	317		// at boot to h. Display goroutine only.
314	func (x XWM) Attach(d server.Display, h host) error {	318		func (x XWM) Attach(d server.Display, h host) error {
		319	+	x.addFD = func(fd int, r, w func()) (fdSource, error) {
		320	+	s, err := d.AddFDRW(fd, r, w)
		321	+	if err != nil {
		322	+	return nil, err
		323	+	}
		324	+	return s, nil
		325	+	}
315	src, err := d.AddFDRW(x.conn.Fd(), x.onReadable, x.onWritable)	326		src, err := d.AddFDRW(x.conn.Fd(), x.onReadable, x.onWritable)
316	if err != nil {	327		if err != nil {
317	return fmt.Errorf("xwm: watch X socket: %w", err)	328		return fmt.Errorf("xwm: watch X socket: %w", err)

@@ -323,6 +334,7 @@ func (x XWM) Attach(d server.Display, h host) error {
323	// attach is Attach over its seams: the event source and the display's Post.	334		// attach is Attach over its seams: the event source and the display's Post.
324	func (x *XWM) attach(src fdSource, h host, post func(func())) {	335		func (x *XWM) attach(src fdSource, h host, post func(func())) {
325	x.src, x.host, x.post = src, h, post	336		x.src, x.host, x.post = src, h, post
		337	+	x.after = h.After
326	x.flushFn = func() {	338		x.flushFn = func() {
327	x.posted = false	339		x.posted = false
328	x.flush()	340		x.flush()

@@ -352,6 +364,7 @@ func (x *XWM) Close() {
352	return	364		return
353	}	365		}
354	x.closed = true	366		x.closed = true
		367	+	x.selClose()
355	s := x.stats	368		s := x.stats
356	x.log.Info().Uint64("events", s.Events).Uint64("replies", s.Replies).Uint64("errors", s.Errors).	369		x.log.Info().Uint64("events", s.Events).Uint64("replies", s.Replies).Uint64("errors", s.Errors).
357	Uint64("unattributed", s.Unattributed).Uint64("stale", s.Stale).Uint64("ring_full", s.RingFull).	370		Uint64("unattributed", s.Unattributed).Uint64("stale", s.Stale).Uint64("ring_full", s.RingFull).