fix(vt,daemon): pass through app OSC 52 clipboard to attached client

Apps inside a pane (e.g. claude CLI auto-copy) emit OSC 52 clipboard
sequences that pkg/vt's Screen parsed and silently discarded. Surface
them via a new Screen.OnClipboard callback and re-emit the normalized
sequence to the attached client through the same bounded output-send
path copy mode already uses for its own yank-to-clipboard.

commit: 63403142b709caf4db296a3cb0be68dce4fc1c4f
author: brice · 3mo ago · 2026-07-04 13:50 UTC
parent: 51529aa
signature: GPG VerifiedCD88F9E564E0102646FB6077A1A07C7C7C3E349D · arch-gpg Verified for the committer email

6 files · +268 -4

M internal/usecase/copy/mode.go +12 -0


@@ -239,6 +239,18 @@ func OSC52(text string) [][]byte {
239	239		return [][]byte{[]byte("\x1b]52;c;" + encoded + "\x07")}
240	240		}
241	241
	242	+	// OSC52FromBase64 builds the normalized OSC 52 sequence to forward a
	243	+	// clipboard set request that a pane app already emitted as base64. It
	244	+	// returns nil if b64 is not valid base64 or its decoded length exceeds
	245	+	// OSC52MaxPayloadBytes — callers must drop the request silently in that case.
	246	+	func OSC52FromBase64(b64 string) []byte {
	247	+	decoded, err := base64.StdEncoding.DecodeString(b64)
	248	+	if err != nil \|\| len(decoded) > OSC52MaxPayloadBytes {
	249	+	return nil
	250	+	}
	251	+	return []byte("\x1b]52;c;" + b64 + "\x07")
	252	+	}
	253	+
242	254		func strconvItoa(n int) string {
243	255		if n == 0 {
244	256		return "0"


@@ -239,6 +239,18 @@ func OSC52(text string) [][]byte {
239	return [][]byte{[]byte("\x1b]52;c;" + encoded + "\x07")}	239		return [][]byte{[]byte("\x1b]52;c;" + encoded + "\x07")}
240	}	240		}
241		241
		242	+	// OSC52FromBase64 builds the normalized OSC 52 sequence to forward a
		243	+	// clipboard set request that a pane app already emitted as base64. It
		244	+	// returns nil if b64 is not valid base64 or its decoded length exceeds
		245	+	// OSC52MaxPayloadBytes — callers must drop the request silently in that case.
		246	+	func OSC52FromBase64(b64 string) []byte {
		247	+	decoded, err := base64.StdEncoding.DecodeString(b64)
		248	+	if err != nil \|\| len(decoded) > OSC52MaxPayloadBytes {
		249	+	return nil
		250	+	}
		251	+	return []byte("\x1b]52;c;" + b64 + "\x07")
		252	+	}
		253	+
242	func strconvItoa(n int) string {	254		func strconvItoa(n int) string {
243	if n == 0 {	255		if n == 0 {
244	return "0"	256		return "0"

A internal/usecase/daemon/clipboard.go +30 -0

@@ -0,0 +1,30 @@
	1	+	package daemon
	2	+
	3	+	import (
	4	+	scopy "github.com/bnema/vev/internal/usecase/copy"
	5	+	)
	6	+
	7	+	// forwardClipboard re-emits an app-originated OSC 52 clipboard set request
	8	+	// (already captured off the pane's screen while ptyReader held pane.mu, then
	9	+	// handed here after that lock is released) to the session's attached client,
	10	+	// if any. Invalid base64 or an oversized decoded payload is dropped silently,
	11	+	// matching copy mode's own cap (scopy.OSC52MaxPayloadBytes). The caller must
	12	+	// not hold pane.mu, tab.mu, or session.mu.
	13	+	func (d Daemon) forwardClipboard(sess session, b64 string) {
	14	+	seq := scopy.OSC52FromBase64(b64)
	15	+	if seq == nil {
	16	+	return
	17	+	}
	18	+
	19	+	sess.mu.Lock()
	20	+	ac := sess.client
	21	+	sess.mu.Unlock()
	22	+	if ac == nil {
	23	+	return
	24	+	}
	25	+
	26	+	failed, err := d.boundedSendOutputErrTransport(ac, seq)
	27	+	if err != nil {
	28	+	d.detachOnSendError(sess, ac, failed)
	29	+	}
	30	+	}

@@ -0,0 +1,30 @@
	1	+	package daemon
	2	+
	3	+	import (
	4	+	scopy "github.com/bnema/vev/internal/usecase/copy"
	5	+	)
	6	+
	7	+	// forwardClipboard re-emits an app-originated OSC 52 clipboard set request
	8	+	// (already captured off the pane's screen while ptyReader held pane.mu, then
	9	+	// handed here after that lock is released) to the session's attached client,
	10	+	// if any. Invalid base64 or an oversized decoded payload is dropped silently,
	11	+	// matching copy mode's own cap (scopy.OSC52MaxPayloadBytes). The caller must
	12	+	// not hold pane.mu, tab.mu, or session.mu.
	13	+	func (d Daemon) forwardClipboard(sess session, b64 string) {
	14	+	seq := scopy.OSC52FromBase64(b64)
	15	+	if seq == nil {
	16	+	return
	17	+	}
	18	+
	19	+	sess.mu.Lock()
	20	+	ac := sess.client
	21	+	sess.mu.Unlock()
	22	+	if ac == nil {
	23	+	return
	24	+	}
	25	+
	26	+	failed, err := d.boundedSendOutputErrTransport(ac, seq)
	27	+	if err != nil {
	28	+	d.detachOnSendError(sess, ac, failed)
	29	+	}
	30	+	}

A internal/usecase/daemon/clipboard_test.go +122 -0

@@ -0,0 +1,122 @@
	1	+	package daemon
	2	+
	3	+	import (
	4	+	"context"
	5	+	"encoding/base64"
	6	+	"io"
	7	+	"strings"
	8	+	"testing"
	9	+
	10	+	"github.com/stretchr/testify/mock"
	11	+	"github.com/stretchr/testify/require"
	12	+
	13	+	"github.com/bnema/vev/internal/ports"
	14	+	portsmocks "github.com/bnema/vev/internal/ports/mocks"
	15	+	scopy "github.com/bnema/vev/internal/usecase/copy"
	16	+	"github.com/bnema/vev/pkg/renderer"
	17	+	)
	18	+
	19	+	// chunkReadPTY returns a MockPTY whose Read yields each chunk in order, then
	20	+	// reports io.EOF — driving ptyReader through exactly len(chunks) reads before
	21	+	// it unwinds via reapPane, matching the style of TestPTYQueryGetsResponseWrittenBackToPTY.
	22	+	func chunkReadPTY(t testing.T, chunks ...[]byte) portsmocks.MockPTY {
	23	+	t.Helper()
	24	+	p := portsmocks.NewMockPTY(t)
	25	+	p.EXPECT().Read(mock.Anything).RunAndReturn(func(buf []byte) (int, error) {
	26	+	if len(chunks) == 0 {
	27	+	return 0, io.EOF
	28	+	}
	29	+	n := copy(buf, chunks[0])
	30	+	chunks = chunks[1:]
	31	+	return n, nil
	32	+	})
	33	+	p.EXPECT().Write(mock.Anything).Return(0, nil).Maybe()
	34	+	p.EXPECT().Close().Return(nil).Maybe()
	35	+	return p
	36	+	}
	37	+
	38	+	func TestPTYReaderForwardsOSC52ClipboardToAttachedClient(t *testing.T) {
	39	+	d := newTestDaemon(t, nil, stubClock{})
	40	+	p := chunkReadPTY(t, []byte("\x1b]52;c;aGVsbG8=\x07"))
	41	+
	42	+	tr, sends := newCapturingTransport(t)
	43	+	sctx, cancel := context.WithCancel(context.Background())
	44	+	defer cancel()
	45	+	win := newTestTabWithContext(p, sctx, cancel)
	46	+	ac := &attachedClient{tr: tr, rend: renderer.New(renderer.Capabilities{})}
	47	+	sess := &session{id: "clip", name: "clip", tabs: []*tab{win}, ctx: sctx, cancel: cancel, client: ac}
	48	+	ac.setSession(sess)
	49	+	d.sessions[sess.id] = sess
	50	+
	51	+	d.sessWg.Add(1)
	52	+	d.ptyReader(sess, win, win.focusedPane())
	53	+
	54	+	f := awaitFrame(t, sends, ports.MsgOutput)
	55	+	out, err := ports.UnmarshalOutput(f.Payload)
	56	+	require.NoError(t, err)
	57	+	require.Contains(t, string(out.Data), "\x1b]52;c;aGVsbG8=\x07")
	58	+	}
	59	+
	60	+	func TestPTYReaderDropsOversizedClipboardPayload(t *testing.T) {
	61	+	d := newTestDaemon(t, nil, stubClock{})
	62	+	big := strings.Repeat("a", scopy.OSC52MaxPayloadBytes+1)
	63	+	b64 := base64.StdEncoding.EncodeToString([]byte(big))
	64	+	p := chunkReadPTY(t, []byte("\x1b]52;c;"+b64+"\x07"))
	65	+
	66	+	tr, sends := newCapturingTransport(t)
	67	+	sctx, cancel := context.WithCancel(context.Background())
	68	+	defer cancel()
	69	+	win := newTestTabWithContext(p, sctx, cancel)
	70	+	ac := &attachedClient{tr: tr, rend: renderer.New(renderer.Capabilities{})}
	71	+	sess := &session{id: "clip-big", name: "clip-big", tabs: []*tab{win}, ctx: sctx, cancel: cancel, client: ac}
	72	+	ac.setSession(sess)
	73	+	d.sessions[sess.id] = sess
	74	+
	75	+	d.sessWg.Add(1)
	76	+	d.ptyReader(sess, win, win.focusedPane())
	77	+
	78	+	select {
	79	+	case f := <-sends:
	80	+	require.NotEqual(t, ports.MsgOutput, f.Type)
	81	+	default:
	82	+	}
	83	+	}
	84	+
	85	+	func TestPTYReaderDropsInvalidBase64Clipboard(t *testing.T) {
	86	+	d := newTestDaemon(t, nil, stubClock{})
	87	+	p := chunkReadPTY(t, []byte("\x1b]52;c;not-valid-base64!!\x07"))
	88	+
	89	+	tr, sends := newCapturingTransport(t)
	90	+	sctx, cancel := context.WithCancel(context.Background())
	91	+	defer cancel()
	92	+	win := newTestTabWithContext(p, sctx, cancel)
	93	+	ac := &attachedClient{tr: tr, rend: renderer.New(renderer.Capabilities{})}
	94	+	sess := &session{id: "clip-bad", name: "clip-bad", tabs: []*tab{win}, ctx: sctx, cancel: cancel, client: ac}
	95	+	ac.setSession(sess)
	96	+	d.sessions[sess.id] = sess
	97	+
	98	+	d.sessWg.Add(1)
	99	+	d.ptyReader(sess, win, win.focusedPane())
	100	+
	101	+	select {
	102	+	case f := <-sends:
	103	+	require.NotEqual(t, ports.MsgOutput, f.Type)
	104	+	default:
	105	+	}
	106	+	}
	107	+
	108	+	func TestPTYReaderClipboardNoAttachedClientDoesNotPanic(t *testing.T) {
	109	+	d := newTestDaemon(t, nil, stubClock{})
	110	+	p := chunkReadPTY(t, []byte("\x1b]52;c;aGVsbG8=\x07"))
	111	+
	112	+	sctx, cancel := context.WithCancel(context.Background())
	113	+	defer cancel()
	114	+	win := newTestTabWithContext(p, sctx, cancel)
	115	+	sess := &session{id: "clip-noclient", name: "clip-noclient", tabs: []*tab{win}, ctx: sctx, cancel: cancel}
	116	+	d.sessions[sess.id] = sess
	117	+
	118	+	d.sessWg.Add(1)
	119	+	require.NotPanics(t, func() {
	120	+	d.ptyReader(sess, win, win.focusedPane())
	121	+	})
	122	+	}

@@ -0,0 +1,122 @@
	1	+	package daemon
	2	+
	3	+	import (
	4	+	"context"
	5	+	"encoding/base64"
	6	+	"io"
	7	+	"strings"
	8	+	"testing"
	9	+
	10	+	"github.com/stretchr/testify/mock"
	11	+	"github.com/stretchr/testify/require"
	12	+
	13	+	"github.com/bnema/vev/internal/ports"
	14	+	portsmocks "github.com/bnema/vev/internal/ports/mocks"
	15	+	scopy "github.com/bnema/vev/internal/usecase/copy"
	16	+	"github.com/bnema/vev/pkg/renderer"
	17	+	)
	18	+
	19	+	// chunkReadPTY returns a MockPTY whose Read yields each chunk in order, then
	20	+	// reports io.EOF — driving ptyReader through exactly len(chunks) reads before
	21	+	// it unwinds via reapPane, matching the style of TestPTYQueryGetsResponseWrittenBackToPTY.
	22	+	func chunkReadPTY(t testing.T, chunks ...[]byte) portsmocks.MockPTY {
	23	+	t.Helper()
	24	+	p := portsmocks.NewMockPTY(t)
	25	+	p.EXPECT().Read(mock.Anything).RunAndReturn(func(buf []byte) (int, error) {
	26	+	if len(chunks) == 0 {
	27	+	return 0, io.EOF
	28	+	}
	29	+	n := copy(buf, chunks[0])
	30	+	chunks = chunks[1:]
	31	+	return n, nil
	32	+	})
	33	+	p.EXPECT().Write(mock.Anything).Return(0, nil).Maybe()
	34	+	p.EXPECT().Close().Return(nil).Maybe()
	35	+	return p
	36	+	}
	37	+
	38	+	func TestPTYReaderForwardsOSC52ClipboardToAttachedClient(t *testing.T) {
	39	+	d := newTestDaemon(t, nil, stubClock{})
	40	+	p := chunkReadPTY(t, []byte("\x1b]52;c;aGVsbG8=\x07"))
	41	+
	42	+	tr, sends := newCapturingTransport(t)
	43	+	sctx, cancel := context.WithCancel(context.Background())
	44	+	defer cancel()
	45	+	win := newTestTabWithContext(p, sctx, cancel)
	46	+	ac := &attachedClient{tr: tr, rend: renderer.New(renderer.Capabilities{})}
	47	+	sess := &session{id: "clip", name: "clip", tabs: []*tab{win}, ctx: sctx, cancel: cancel, client: ac}
	48	+	ac.setSession(sess)
	49	+	d.sessions[sess.id] = sess
	50	+
	51	+	d.sessWg.Add(1)
	52	+	d.ptyReader(sess, win, win.focusedPane())
	53	+
	54	+	f := awaitFrame(t, sends, ports.MsgOutput)
	55	+	out, err := ports.UnmarshalOutput(f.Payload)
	56	+	require.NoError(t, err)
	57	+	require.Contains(t, string(out.Data), "\x1b]52;c;aGVsbG8=\x07")
	58	+	}
	59	+
	60	+	func TestPTYReaderDropsOversizedClipboardPayload(t *testing.T) {
	61	+	d := newTestDaemon(t, nil, stubClock{})
	62	+	big := strings.Repeat("a", scopy.OSC52MaxPayloadBytes+1)
	63	+	b64 := base64.StdEncoding.EncodeToString([]byte(big))
	64	+	p := chunkReadPTY(t, []byte("\x1b]52;c;"+b64+"\x07"))
	65	+
	66	+	tr, sends := newCapturingTransport(t)
	67	+	sctx, cancel := context.WithCancel(context.Background())
	68	+	defer cancel()
	69	+	win := newTestTabWithContext(p, sctx, cancel)
	70	+	ac := &attachedClient{tr: tr, rend: renderer.New(renderer.Capabilities{})}
	71	+	sess := &session{id: "clip-big", name: "clip-big", tabs: []*tab{win}, ctx: sctx, cancel: cancel, client: ac}
	72	+	ac.setSession(sess)
	73	+	d.sessions[sess.id] = sess
	74	+
	75	+	d.sessWg.Add(1)
	76	+	d.ptyReader(sess, win, win.focusedPane())
	77	+
	78	+	select {
	79	+	case f := <-sends:
	80	+	require.NotEqual(t, ports.MsgOutput, f.Type)
	81	+	default:
	82	+	}
	83	+	}
	84	+
	85	+	func TestPTYReaderDropsInvalidBase64Clipboard(t *testing.T) {
	86	+	d := newTestDaemon(t, nil, stubClock{})
	87	+	p := chunkReadPTY(t, []byte("\x1b]52;c;not-valid-base64!!\x07"))
	88	+
	89	+	tr, sends := newCapturingTransport(t)
	90	+	sctx, cancel := context.WithCancel(context.Background())
	91	+	defer cancel()
	92	+	win := newTestTabWithContext(p, sctx, cancel)
	93	+	ac := &attachedClient{tr: tr, rend: renderer.New(renderer.Capabilities{})}
	94	+	sess := &session{id: "clip-bad", name: "clip-bad", tabs: []*tab{win}, ctx: sctx, cancel: cancel, client: ac}
	95	+	ac.setSession(sess)
	96	+	d.sessions[sess.id] = sess
	97	+
	98	+	d.sessWg.Add(1)
	99	+	d.ptyReader(sess, win, win.focusedPane())
	100	+
	101	+	select {
	102	+	case f := <-sends:
	103	+	require.NotEqual(t, ports.MsgOutput, f.Type)
	104	+	default:
	105	+	}
	106	+	}
	107	+
	108	+	func TestPTYReaderClipboardNoAttachedClientDoesNotPanic(t *testing.T) {
	109	+	d := newTestDaemon(t, nil, stubClock{})
	110	+	p := chunkReadPTY(t, []byte("\x1b]52;c;aGVsbG8=\x07"))
	111	+
	112	+	sctx, cancel := context.WithCancel(context.Background())
	113	+	defer cancel()
	114	+	win := newTestTabWithContext(p, sctx, cancel)
	115	+	sess := &session{id: "clip-noclient", name: "clip-noclient", tabs: []*tab{win}, ctx: sctx, cancel: cancel}
	116	+	d.sessions[sess.id] = sess
	117	+
	118	+	d.sessWg.Add(1)
	119	+	require.NotPanics(t, func() {
	120	+	d.ptyReader(sess, win, win.focusedPane())
	121	+	})
	122	+	}

M internal/usecase/daemon/render.go +8 -0


@@ -54,11 +54,13 @@ func (d Daemon) ptyReader(sess session, tb tab, p pane) {
54	54		}
55	55		buf := make([]byte, ptyReadBufSize)
56	56		var resp []byte
	57	+	var clipboards []string
57	58		attentionCh := make(chan struct{}, 1)
58	59		p.mu.Lock()
59	60		p.screen.OnResponse = func(b []byte) { resp = append(resp, b...) }
60	61		p.screen.OnBell = func() { signal(attentionCh) }
61	62		p.screen.OnNotify = func(string, string) { signal(attentionCh) }
	63	+	p.screen.OnClipboard = func(b64 string) { clipboards = append(clipboards, b64) }
62	64		p.mu.Unlock()
63	65		for {
64	66		n, err := p.pty.Read(buf)

@@ -74,6 +76,12 @@ func (d Daemon) ptyReader(sess session, tb tab, p pane) {
74	76		d.noteAttention(sess, tb)
75	77		default:
76	78		}
	79	+	if len(clipboards) > 0 {
	80	+	for _, b64 := range clipboards {
	81	+	d.forwardClipboard(sess, b64)
	82	+	}
	83	+	clipboards = clipboards[:0]
	84	+	}
77	85		if len(resp) > 0 {
78	86		if _, writeErr := p.pty.Write(resp); writeErr != nil {
79	87		d.log.Warn("pty response write failed", "err", writeErr, "session", sess.name)


@@ -54,11 +54,13 @@ func (d Daemon) ptyReader(sess session, tb tab, p pane) {
54	}	54		}
55	buf := make([]byte, ptyReadBufSize)	55		buf := make([]byte, ptyReadBufSize)
56	var resp []byte	56		var resp []byte
		57	+	var clipboards []string
57	attentionCh := make(chan struct{}, 1)	58		attentionCh := make(chan struct{}, 1)
58	p.mu.Lock()	59		p.mu.Lock()
59	p.screen.OnResponse = func(b []byte) { resp = append(resp, b...) }	60		p.screen.OnResponse = func(b []byte) { resp = append(resp, b...) }
60	p.screen.OnBell = func() { signal(attentionCh) }	61		p.screen.OnBell = func() { signal(attentionCh) }
61	p.screen.OnNotify = func(string, string) { signal(attentionCh) }	62		p.screen.OnNotify = func(string, string) { signal(attentionCh) }
		63	+	p.screen.OnClipboard = func(b64 string) { clipboards = append(clipboards, b64) }
62	p.mu.Unlock()	64		p.mu.Unlock()
63	for {	65		for {
64	n, err := p.pty.Read(buf)	66		n, err := p.pty.Read(buf)

@@ -74,6 +76,12 @@ func (d Daemon) ptyReader(sess session, tb tab, p pane) {
74	d.noteAttention(sess, tb)	76		d.noteAttention(sess, tb)
75	default:	77		default:
76	}	78		}
		79	+	if len(clipboards) > 0 {
		80	+	for _, b64 := range clipboards {
		81	+	d.forwardClipboard(sess, b64)
		82	+	}
		83	+	clipboards = clipboards[:0]
		84	+	}
77	if len(resp) > 0 {	85		if len(resp) > 0 {
78	if _, writeErr := p.pty.Write(resp); writeErr != nil {	86		if _, writeErr := p.pty.Write(resp); writeErr != nil {
79	d.log.Warn("pty response write failed", "err", writeErr, "session", sess.name)	87		d.log.Warn("pty response write failed", "err", writeErr, "session", sess.name)

M pkg/vt/screen.go +32 -4


@@ -25,7 +25,7 @@ type screenState struct {
25	25		savedCursor cursorState
26	26		}
27	27
28		-	const maxEscapeBufferLen = 4096
	28	+	const maxEscapeBufferLen = 128 * 1024
29	29
30	30		type Screen struct {
31	31		Frame renderer.Frame

@@ -47,6 +47,11 @@ type Screen struct {
47	47		// notifications: OSC 9 (body only) and OSC 777 "notify" (title;body).
48	48		// All other OSC payloads remain discarded. Nil disables it.
49	49		OnNotify func(title, body string)
	50	+	// OnClipboard is called synchronously from Write for a complete OSC 52
	51	+	// clipboard set request from the child ("52;<selection>;<base64>"),
	52	+	// receiving the raw base64 payload. Clipboard queries (data == "?") and
	53	+	// malformed payloads are ignored and never invoke it. Nil disables it.
	54	+	OnClipboard func(b64 string)
50	55
51	56		defaultFG renderer.RGB
52	57		defaultBG renderer.RGB

@@ -625,13 +630,18 @@ func appendOSCColorComponent(dst []byte, c uint8) []byte {
625	630		}
626	631
627	632		// handleOSC inspects a complete OSC payload (between "ESC ]" and its
628		-	// terminator). Only notification sequences are acted on; titles, clipboard
629		-	// and every other OSC are still discarded.
	633	+	// terminator). Notification sequences (OSC 9, OSC 777 "notify") and clipboard
	634	+	// set requests (OSC 52) are acted on; titles and every other OSC are still
	635	+	// discarded.
630	636		func (s *Screen) handleOSC(payload []byte) {
	637	+	p := string(payload)
	638	+	if strings.HasPrefix(p, "52;") {
	639	+	s.handleOSC52(p[len("52;"):])
	640	+	return
	641	+	}
631	642		if s.OnNotify == nil {
632	643		return
633	644		}
634		-	p := string(payload)
635	645		switch {
636	646		case strings.HasPrefix(p, "9;"):
637	647		if strings.HasPrefix(p, "9;4;") {

@@ -654,6 +664,24 @@ func (s *Screen) handleOSC(payload []byte) {
654	664		}
655	665		}
656	666
	667	+	// handleOSC52 parses the "<selection>;<data>" remainder of an OSC 52
	668	+	// clipboard payload (selection may be empty; split on the first ";"). A
	669	+	// clipboard query (data == "?") is always ignored — vev never answers
	670	+	// clipboard queries. A payload with no second ";" is malformed and ignored.
	671	+	func (s *Screen) handleOSC52(rest string) {
	672	+	idx := strings.IndexByte(rest, ';')
	673	+	if idx < 0 {
	674	+	return
	675	+	}
	676	+	data := rest[idx+1:]
	677	+	if data == "?" {
	678	+	return
	679	+	}
	680	+	if s.OnClipboard != nil {
	681	+	s.OnClipboard(data)
	682	+	}
	683	+	}
	684	+
657	685		func consumeSTString(data []byte) (consumed int, partial bool) {
658	686		for i := 2; i < len(data); i++ {
659	687		if data[i] == 0x1b && i+1 < len(data) && data[i+1] == '\\' {

 	savedCursor  cursorState
 }
-const maxEscapeBufferLen = 4096
+const maxEscapeBufferLen = 128 * 1024
 type Screen struct {
 	Frame renderer.Frame
 	// notifications: OSC 9 (body only) and OSC 777 "notify" (title;body).
 	// All other OSC payloads remain discarded. Nil disables it.
 	OnNotify func(title, body string)
+	// OnClipboard is called synchronously from Write for a complete OSC 52
+	// clipboard set request from the child ("52;<selection>;<base64>"),
+	// receiving the raw base64 payload. Clipboard queries (data == "?") and
+	// malformed payloads are ignored and never invoke it. Nil disables it.
+	OnClipboard func(b64 string)
 	defaultFG          renderer.RGB
 	defaultBG          renderer.RGB
 }
 // handleOSC inspects a complete OSC payload (between "ESC ]" and its
-// terminator). Only notification sequences are acted on; titles, clipboard
+// terminator). Notification sequences (OSC 9, OSC 777 "notify") and clipboard
-// and every other OSC are still discarded.
+// set requests (OSC 52) are acted on; titles and every other OSC are still
+// discarded.
 func (s *Screen) handleOSC(payload []byte) {
+	p := string(payload)
+	if strings.HasPrefix(p, "52;") {
+		s.handleOSC52(p[len("52;"):])
+		return
+	}
 	if s.OnNotify == nil {
 		return
 	}
-	p := string(payload)
 	switch {
 	case strings.HasPrefix(p, "9;"):
 		if strings.HasPrefix(p, "9;4;") {
 	}
 }
+// handleOSC52 parses the "<selection>;<data>" remainder of an OSC 52
+// clipboard payload (selection may be empty; split on the first ";"). A
+// clipboard query (data == "?") is always ignored — vev never answers
+// clipboard queries. A payload with no second ";" is malformed and ignored.
+func (s *Screen) handleOSC52(rest string) {
+	idx := strings.IndexByte(rest, ';')
+	if idx < 0 {
+		return
+	}
+	data := rest[idx+1:]
+	if data == "?" {
+		return
+	}
+	if s.OnClipboard != nil {
+		s.OnClipboard(data)
+	}
+}
 func consumeSTString(data []byte) (consumed int, partial bool) {
 	for i := 2; i < len(data); i++ {
 		if data[i] == 0x1b && i+1 < len(data) && data[i+1] == '\\' {

M pkg/vt/screen_test.go +64 -0


@@ -157,6 +157,70 @@ func TestOnNotifySplitAcrossWrites(t *testing.T) {
157	157		require.Equal(t, 1, calls)
158	158		}
159	159
	160	+	func TestOnClipboardBELTerminated(t *testing.T) {
	161	+	s := NewScreen(10, 2)
	162	+	var got string
	163	+	calls := 0
	164	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
	165	+	s.Write([]byte("\x1b]52;c;aGVsbG8=\x07"))
	166	+	require.Equal(t, 1, calls)
	167	+	require.Equal(t, "aGVsbG8=", got)
	168	+	}
	169	+
	170	+	func TestOnClipboardSTTerminated(t *testing.T) {
	171	+	s := NewScreen(10, 2)
	172	+	var got string
	173	+	calls := 0
	174	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
	175	+	s.Write([]byte("\x1b]52;c;aGVsbG8=\x1b\\"))
	176	+	require.Equal(t, 1, calls)
	177	+	require.Equal(t, "aGVsbG8=", got)
	178	+	}
	179	+
	180	+	func TestOnClipboardQueryIgnored(t *testing.T) {
	181	+	s := NewScreen(10, 2)
	182	+	calls := 0
	183	+	s.OnClipboard = func(string) { calls++ }
	184	+	s.Write([]byte("\x1b]52;c;?\x07"))
	185	+	require.Equal(t, 0, calls)
	186	+	}
	187	+
	188	+	func TestOnClipboardEmptySelection(t *testing.T) {
	189	+	s := NewScreen(10, 2)
	190	+	var got string
	191	+	calls := 0
	192	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
	193	+	s.Write([]byte("\x1b]52;;aGVsbG8=\x07"))
	194	+	require.Equal(t, 1, calls)
	195	+	require.Equal(t, "aGVsbG8=", got)
	196	+	}
	197	+
	198	+	func TestOnClipboardNilCallbackDoesNotPanic(t *testing.T) {
	199	+	s := NewScreen(10, 2)
	200	+	require.NotPanics(t, func() {
	201	+	s.Write([]byte("\x1b]52;c;aGVsbG8=\x07"))
	202	+	})
	203	+	}
	204	+
	205	+	func TestOnClipboardSplitAcrossWrites(t *testing.T) {
	206	+	s := NewScreen(10, 2)
	207	+	var got string
	208	+	calls := 0
	209	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
	210	+	s.Write([]byte("\x1b]52;c;aGVs"))
	211	+	s.Write([]byte("bG8=\x07"))
	212	+	require.Equal(t, 1, calls)
	213	+	require.Equal(t, "aGVsbG8=", got)
	214	+	}
	215	+
	216	+	func TestOnClipboardNoSecondSemicolonIgnored(t *testing.T) {
	217	+	s := NewScreen(10, 2)
	218	+	calls := 0
	219	+	s.OnClipboard = func(string) { calls++ }
	220	+	s.Write([]byte("\x1b]52;c\x07")) // no second ";" -> no data field
	221	+	require.Equal(t, 0, calls)
	222	+	}
	223	+
160	224		// ---------------------------------------------------------------------------
161	225		// Printable ASCII / UTF-8
162	226		// ---------------------------------------------------------------------------


@@ -157,6 +157,70 @@ func TestOnNotifySplitAcrossWrites(t *testing.T) {
157	require.Equal(t, 1, calls)	157		require.Equal(t, 1, calls)
158	}	158		}
159		159
		160	+	func TestOnClipboardBELTerminated(t *testing.T) {
		161	+	s := NewScreen(10, 2)
		162	+	var got string
		163	+	calls := 0
		164	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
		165	+	s.Write([]byte("\x1b]52;c;aGVsbG8=\x07"))
		166	+	require.Equal(t, 1, calls)
		167	+	require.Equal(t, "aGVsbG8=", got)
		168	+	}
		169	+
		170	+	func TestOnClipboardSTTerminated(t *testing.T) {
		171	+	s := NewScreen(10, 2)
		172	+	var got string
		173	+	calls := 0
		174	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
		175	+	s.Write([]byte("\x1b]52;c;aGVsbG8=\x1b\\"))
		176	+	require.Equal(t, 1, calls)
		177	+	require.Equal(t, "aGVsbG8=", got)
		178	+	}
		179	+
		180	+	func TestOnClipboardQueryIgnored(t *testing.T) {
		181	+	s := NewScreen(10, 2)
		182	+	calls := 0
		183	+	s.OnClipboard = func(string) { calls++ }
		184	+	s.Write([]byte("\x1b]52;c;?\x07"))
		185	+	require.Equal(t, 0, calls)
		186	+	}
		187	+
		188	+	func TestOnClipboardEmptySelection(t *testing.T) {
		189	+	s := NewScreen(10, 2)
		190	+	var got string
		191	+	calls := 0
		192	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
		193	+	s.Write([]byte("\x1b]52;;aGVsbG8=\x07"))
		194	+	require.Equal(t, 1, calls)
		195	+	require.Equal(t, "aGVsbG8=", got)
		196	+	}
		197	+
		198	+	func TestOnClipboardNilCallbackDoesNotPanic(t *testing.T) {
		199	+	s := NewScreen(10, 2)
		200	+	require.NotPanics(t, func() {
		201	+	s.Write([]byte("\x1b]52;c;aGVsbG8=\x07"))
		202	+	})
		203	+	}
		204	+
		205	+	func TestOnClipboardSplitAcrossWrites(t *testing.T) {
		206	+	s := NewScreen(10, 2)
		207	+	var got string
		208	+	calls := 0
		209	+	s.OnClipboard = func(b64 string) { got = b64; calls++ }
		210	+	s.Write([]byte("\x1b]52;c;aGVs"))
		211	+	s.Write([]byte("bG8=\x07"))
		212	+	require.Equal(t, 1, calls)
		213	+	require.Equal(t, "aGVsbG8=", got)
		214	+	}
		215	+
		216	+	func TestOnClipboardNoSecondSemicolonIgnored(t *testing.T) {
		217	+	s := NewScreen(10, 2)
		218	+	calls := 0
		219	+	s.OnClipboard = func(string) { calls++ }
		220	+	s.Write([]byte("\x1b]52;c\x07")) // no second ";" -> no data field
		221	+	require.Equal(t, 0, calls)
		222	+	}
		223	+
160	// ---------------------------------------------------------------------------	224		// ---------------------------------------------------------------------------
161	// Printable ASCII / UTF-8	225		// Printable ASCII / UTF-8
162	// ---------------------------------------------------------------------------	226		// ---------------------------------------------------------------------------