runtime_primitives.go RawHistoryFolder

1package client
2
3import (
4	"crypto/rand"
5	"fmt"
6	"sync"
7
8	"github.com/bnema/vev/internal/ports"
9	"github.com/bnema/vev/internal/protocol"
10)
11
12// ProtocolError is a session- or protocol-level failure reported before attach.
13type ProtocolError struct {
14	Code uint16
15	Text string
16}
17
18func (e *ProtocolError) Error() string {
19	if e.Text == "" {
20		return fmt.Sprintf("daemon rejected attach (code %d)", e.Code)
21	}
22	return e.Text
23}
24
25func newClientID() [16]byte {
26	var id [16]byte
27	if _, err := rand.Read(id[:]); err != nil {
28		panic("crypto/rand failed generating client ID: " + err.Error())
29	}
30	return id
31}
32
33// requestedOutputWindow is the number of unacknowledged Output states this
34// client lets the daemon keep in flight: what the carriage prefers, or the
35// protocol maximum when it states no preference. A window of one makes every
36// frame wait a full round trip, which stalls scrolling on any remote link.
37func requestedOutputWindow(connection ports.ClientConnection) uint8 {
38	if window := connection.Capabilities().PreferredOutputWindow; window != 0 {
39		return window
40	}
41	return protocol.MaxOutputWindow
42}
43
44type foregroundSendLease struct {
45	mu     sync.Mutex
46	active bool
47}
48
49func newForegroundSendLease() *foregroundSendLease { return &foregroundSendLease{active: true} }
50
51func (l *foregroundSendLease) send(send func() bool) bool {
52	l.mu.Lock()
53	defer l.mu.Unlock()
54	return l.active && send()
55}
56
57func (l *foregroundSendLease) stop() {
58	l.mu.Lock()
59	l.active = false
60	l.mu.Unlock()
61}
62
63const stdinBufSize = 4096