90 lines
2.2 KiB
Go
90 lines
2.2 KiB
Go
//go:build linux
|
|
|
|
package evidence
|
|
|
|
import (
|
|
"context"
|
|
|
|
"github.com/jezek/xgb/xproto"
|
|
"github.com/jezek/xgbutil"
|
|
"github.com/jezek/xgbutil/ewmh"
|
|
"github.com/jezek/xgbutil/icccm"
|
|
"github.com/jezek/xgbutil/xevent"
|
|
"github.com/jezek/xgbutil/xprop"
|
|
"github.com/jezek/xgbutil/xwindow"
|
|
)
|
|
|
|
// NewSource returns the real X11 active-window sensor.
|
|
func NewSource() Source { return &x11Source{} }
|
|
|
|
type x11Source struct{}
|
|
|
|
// Watch opens one long-lived X connection, subscribes to _NET_ACTIVE_WINDOW
|
|
// changes on the root window, and emits a snapshot immediately plus on every
|
|
// change. Any failure degrades to an Unavailable snapshot; it never panics the
|
|
// daemon.
|
|
func (s *x11Source) Watch(ctx context.Context, onChange func(WindowSnapshot)) {
|
|
X, err := xgbutil.NewConn()
|
|
if err != nil {
|
|
onChange(unavailable("cannot connect to X server: " + err.Error()))
|
|
<-ctx.Done()
|
|
return
|
|
}
|
|
defer X.Conn().Close()
|
|
|
|
root := X.RootWin()
|
|
activeAtom, err := xprop.Atm(X, "_NET_ACTIVE_WINDOW")
|
|
if err != nil {
|
|
onChange(unavailable("no _NET_ACTIVE_WINDOW atom: " + err.Error()))
|
|
<-ctx.Done()
|
|
return
|
|
}
|
|
|
|
// Listen for property changes on the root window.
|
|
if err := xwindow.New(X, root).Listen(xproto.EventMaskPropertyChange); err != nil {
|
|
onChange(unavailable("cannot listen on root window: " + err.Error()))
|
|
<-ctx.Done()
|
|
return
|
|
}
|
|
|
|
emit := func() { onChange(snapshot(X)) }
|
|
emit() // immediate current window
|
|
|
|
xevent.PropertyNotifyFun(func(_ *xgbutil.XUtil, ev xevent.PropertyNotifyEvent) {
|
|
if ev.Atom == activeAtom {
|
|
emit()
|
|
}
|
|
}).Connect(X, root)
|
|
|
|
// Run the event loop until ctx is cancelled.
|
|
go func() {
|
|
<-ctx.Done()
|
|
xevent.Quit(X)
|
|
}()
|
|
xevent.Main(X)
|
|
}
|
|
|
|
func snapshot(X *xgbutil.XUtil) WindowSnapshot {
|
|
active, err := ewmh.ActiveWindowGet(X)
|
|
if err != nil || active == 0 {
|
|
return unavailable("no active window")
|
|
}
|
|
title, err := ewmh.WmNameGet(X, active)
|
|
if err != nil || title == "" {
|
|
// Fall back to ICCCM WM_NAME.
|
|
if t, e := icccm.WmNameGet(X, active); e == nil {
|
|
title = t
|
|
}
|
|
}
|
|
var class string
|
|
if wmClass, err := icccm.WmClassGet(X, active); err == nil && wmClass != nil {
|
|
class = wmClass.Class
|
|
}
|
|
return WindowSnapshot{
|
|
Title: title,
|
|
Class: class,
|
|
Health: EvidenceHealth{Available: true},
|
|
}
|
|
}
|
|
|