func (p *Pty) resize(f *os.File) {
var rows, cols int
if terminal.IsTerminal(int(p.Stdout.Fd())) {
rows, cols, _ = p.Size()
} else {
rows = 24
cols = 80
}
ptyx.Setsize(f, rows, cols)
}
func (p *Pty) Record(command string, stdoutCopy io.Writer) error {
// start command in pty
cmd := exec.Command("sh", "-c", command)
cmd.Env = append(os.Environ(), "ASCIINEMA_REC=1")
master, err := pty.Start(cmd)
if err != nil {
return err
}
defer master.Close()
// install WINCH signal handler
signals := make(chan os.Signal, 1)
signal.Notify(signals, syscall.SIGWINCH)
defer signal.Stop(signals)
go func() {
for _ = range signals {
p.resize(master)
}
}()
defer close(signals)
// put stdin in raw mode (if it's a tty)
fd := p.Stdin.Fd()
if terminal.IsTerminal(int(fd)) {
oldState, err := raw.MakeRaw(fd)
if err != nil {
return err
}
defer raw.TcSetAttr(fd, oldState)
}
// do initial resize
p.resize(master)
// start stdin -> master copying
stop := util.Copy(master, p.Stdin)
// copy pty master -> p.stdout & stdoutCopy
stdout := io.MultiWriter(p.Stdout, stdoutCopy)
stdoutWaitChan := make(chan struct{})
go func() {
io.Copy(stdout, master)
stdoutWaitChan <- struct{}{}
}()
// wait for the process to exit and reap it
cmd.Wait()
// wait for master -> stdout copying to finish
//
// sometimes after process exits reading from master blocks forever (race condition?)
// we're using timeout here to overcome this problem
select {
case <-stdoutWaitChan:
case <-time.After(200 * time.Millisecond):
}
// stop stdin -> master copying
stop()
return nil
}