diff --git a/stdin_unix.go b/stdin_unix.go new file mode 100644 index 0000000..e3d32e9 --- /dev/null +++ b/stdin_unix.go @@ -0,0 +1,177 @@ +// 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" + "strconv" + "sync" + "syscall" + "time" + + "golang.org/x/term" +) + +// stdIoTty is an implementation of the Tty API based upon stdin/stdout. +type stdIoTty struct { + fd int + in *os.File + out *os.File + saved *term.State + sig chan os.Signal + cb func() + stopQ chan struct{} + dev string + wg sync.WaitGroup + l sync.Mutex +} + +func (tty *stdIoTty) Read(b []byte) (int, error) { + return tty.in.Read(b) +} + +func (tty *stdIoTty) Write(b []byte) (int, error) { + return tty.out.Write(b) +} + +func (tty *stdIoTty) Close() error { + return nil +} + +func (tty *stdIoTty) 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 + tty.in = os.Stdin + tty.out = os.Stdout + tty.fd = int(tty.in.Fd()) + + if !term.IsTerminal(tty.fd) { + return errors.New("device is not a terminal") + } + + _ = tty.in.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 *stdIoTty) Drain() error { + _ = tty.in.SetReadDeadline(time.Now()) + if err := tcSetBufParams(tty.fd, 0, 0); err != nil { + return err + } + return nil +} + +func (tty *stdIoTty) Stop() error { + tty.l.Lock() + if err := term.Restore(tty.fd, tty.saved); err != nil { + tty.l.Unlock() + return err + } + _ = tty.in.SetReadDeadline(time.Now()) + + signal.Stop(tty.sig) + close(tty.stopQ) + tty.l.Unlock() + + tty.wg.Wait() + + return nil +} + +func (tty *stdIoTty) WindowSize() (int, int, error) { + w, h, err := term.GetSize(tty.fd) + if err != nil { + return 0, 0, err + } + if w == 0 { + w, _ = strconv.Atoi(os.Getenv("COLUMNS")) + } + if w == 0 { + w = 80 // default + } + if h == 0 { + h, _ = strconv.Atoi(os.Getenv("LINES")) + } + if h == 0 { + h = 25 // default + } + return w, h, nil +} + +func (tty *stdIoTty) NotifyResize(cb func()) { + tty.l.Lock() + tty.cb = cb + tty.l.Unlock() +} + +// NewStdioTty opens a tty using standard input/output. +func NewStdIoTty() (Tty, error) { + tty := &stdIoTty{ + sig: make(chan os.Signal), + in: os.Stdin, + out: os.Stdout, + } + var err error + tty.fd = int(tty.in.Fd()) + if !term.IsTerminal(tty.fd) { + return nil, errors.New("not a terminal") + } + if tty.saved, err = term.GetState(tty.fd); err != nil { + return nil, fmt.Errorf("failed to get state: %w", err) + } + return tty, nil +} diff --git a/tty_unix.go b/tty_unix.go index a48b2e6..71b1e7a 100644 --- a/tty_unix.go +++ b/tty_unix.go @@ -21,6 +21,7 @@ import ( "fmt" "os" "os/signal" + "strconv" "sync" "syscall" "time" @@ -136,7 +137,23 @@ func (tty *devTty) Stop() error { } func (tty *devTty) WindowSize() (int, int, error) { - return term.GetSize(tty.fd) + w, h, err := term.GetSize(tty.fd) + if err != nil { + return 0, 0, err + } + if w == 0 { + w, _ = strconv.Atoi(os.Getenv("COLUMNS")) + } + if w == 0 { + w = 80 // default + } + if h == 0 { + h, _ = strconv.Atoi(os.Getenv("LINES")) + } + if h == 0 { + h = 25 // default + } + return w, h, nil } func (tty *devTty) NotifyResize(cb func()) {