diff options
Diffstat (limited to 'vendor/github.com/gdamore/tcell/v2/tty_unix.go')
-rw-r--r-- | vendor/github.com/gdamore/tcell/v2/tty_unix.go | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/vendor/github.com/gdamore/tcell/v2/tty_unix.go b/vendor/github.com/gdamore/tcell/v2/tty_unix.go new file mode 100644 index 000000000..a48b2e6da --- /dev/null +++ b/vendor/github.com/gdamore/tcell/v2/tty_unix.go @@ -0,0 +1,173 @@ +// Copyright 2021 The TCell Authors +// +// Licensed under the Apache License, Version 2.0 (the "License"); +// you may not use file except in compliance with the License. +// You may obtain a copy of the license at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, software +// distributed under the License is distributed on an "AS IS" BASIS, +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +// See the License for the specific language governing permissions and +// limitations under the License. + +// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris zos + +package tcell + +import ( + "errors" + "fmt" + "os" + "os/signal" + "sync" + "syscall" + "time" + + "golang.org/x/term" +) + +// devTty is an implementation of the Tty API based upon /dev/tty. +type devTty struct { + fd int + f *os.File + of *os.File // the first open of /dev/tty + saved *term.State + sig chan os.Signal + cb func() + stopQ chan struct{} + dev string + wg sync.WaitGroup + l sync.Mutex +} + +func (tty *devTty) Read(b []byte) (int, error) { + return tty.f.Read(b) +} + +func (tty *devTty) Write(b []byte) (int, error) { + return tty.f.Write(b) +} + +func (tty *devTty) Close() error { + return nil +} + +func (tty *devTty) Start() error { + tty.l.Lock() + defer tty.l.Unlock() + + // We open another copy of /dev/tty. This is a workaround for unusual behavior + // observed in macOS, apparently caused when a subshell (for example) closes our + // own tty device (when it exits for example). Getting a fresh new one seems to + // resolve the problem. (We believe this is a bug in the macOS tty driver that + // fails to account for dup() references to the same file before applying close() + // related behaviors to the tty.) We're also holding the original copy we opened + // since closing that might have deleterious effects as well. The upshot is that + // we will have up to two separate file handles open on /dev/tty. (Note that when + // using stdin/stdout instead of /dev/tty this problem is not observed.) + var err error + if tty.f, err = os.OpenFile(tty.dev, os.O_RDWR, 0); err != nil { + return err + } + tty.fd = int(tty.of.Fd()) + + if !term.IsTerminal(tty.fd) { + return errors.New("device is not a terminal") + } + + _ = tty.f.SetReadDeadline(time.Time{}) + saved, err := term.MakeRaw(tty.fd) // also sets vMin and vTime + if err != nil { + return err + } + tty.saved = saved + + tty.stopQ = make(chan struct{}) + tty.wg.Add(1) + go func(stopQ chan struct{}) { + defer tty.wg.Done() + for { + select { + case <-tty.sig: + tty.l.Lock() + cb := tty.cb + tty.l.Unlock() + if cb != nil { + cb() + } + case <-stopQ: + return + } + } + }(tty.stopQ) + + signal.Notify(tty.sig, syscall.SIGWINCH) + return nil +} + +func (tty *devTty) Drain() error { + _ = tty.f.SetReadDeadline(time.Now()) + if err := tcSetBufParams(tty.fd, 0, 0); err != nil { + return err + } + return nil +} + +func (tty *devTty) Stop() error { + tty.l.Lock() + if err := term.Restore(tty.fd, tty.saved); err != nil { + tty.l.Unlock() + return err + } + _ = tty.f.SetReadDeadline(time.Now()) + + signal.Stop(tty.sig) + close(tty.stopQ) + tty.l.Unlock() + + tty.wg.Wait() + + // close our tty device -- we'll get another one if we Start again later. + _ = tty.f.Close() + + return nil +} + +func (tty *devTty) WindowSize() (int, int, error) { + return term.GetSize(tty.fd) +} + +func (tty *devTty) NotifyResize(cb func()) { + tty.l.Lock() + tty.cb = cb + tty.l.Unlock() +} + +// NewDevTty opens a /dev/tty based Tty. +func NewDevTty() (Tty, error) { + return NewDevTtyFromDev("/dev/tty") +} + +// NewDevTtyFromDev opens a tty device given a path. This can be useful to bind to other nodes. +func NewDevTtyFromDev(dev string) (Tty, error) { + tty := &devTty{ + dev: dev, + sig: make(chan os.Signal), + } + var err error + if tty.of, err = os.OpenFile(dev, os.O_RDWR, 0); err != nil { + return nil, err + } + tty.fd = int(tty.of.Fd()) + if !term.IsTerminal(tty.fd) { + _ = tty.f.Close() + return nil, errors.New("not a terminal") + } + if tty.saved, err = term.GetState(tty.fd); err != nil { + _ = tty.f.Close() + return nil, fmt.Errorf("failed to get state: %w", err) + } + return tty, nil +} |