Struct screenReconnectingPTY

agent/reconnectingpty/screen.go:27–56

screenReconnectingPTY provides a reconnectable PTY via `screen`.

// screenReconnectingPTY provides a reconnectable PTY via `screen`.
type screenReconnectingPTY struct {
	logger  slog.Logger
	execer  agentexec.Execer
	command *pty.Cmd

	// id holds the id of the session for both creating and attaching.  This will
	// be generated uniquely for each session because without control of the
	// screen daemon we do not have its PID and without the PID screen will do
	// partial matching.  Enforcing a unique ID should guarantee we match on the
	// right session.
	id string

	// mutex prevents concurrent attaches to the session.  Screen will happily
	// spawn two separate sessions with the same name if multiple attaches happen
	// in a close enough interval.  We are not able to control the screen daemon
	// ourselves to prevent this because the daemon will spawn with a hardcoded
	// 24x80 size which results in confusing padding above the prompt once the
	// attach comes in and resizes.
	mutex sync.Mutex

	configFile string

	metrics *prometheus.CounterVec

	state *ptyState
	// timer will close the reconnecting pty when it expires.  The timer will be
	// reset as long as there are active connections.
	timer   *time.Timer
	timeout time.Duration
}

// newScreen creates a new screen-backed reconnecting PTY.  It writes config
// settings and creates the socket directory.  If we could, we would want to