Improved PtyMode (eows lib).

- renamed PtsMode to PtyMode
- used byte array instead of string
- allowed terminal echo on/off (PtyMode only)
- fixed support escaped and control characters (PtyMode only)

Signed-off-by: Sebastien Douheret <sebastien.douheret@iot.bzh>

3 files changed, 62 insertions, 33 deletions

diff --git a/golib/eows/eows-in.go b/golib/eows/eows-in.go
index 89ca891..5e74c76 100644
--- a/golib/eows/eows-in.go
+++ b/golib/eows/eows-in.go
@@ -13,21 +13,21 @@ type DoneChan struct {
 	err    error
 }
 
-// cmdPumpStdin is in charge of receive characters and send them to stdin
-func (e *ExecOverWS) cmdPumpStdin(inw *os.File) {
+// pumpStdin is in charge of receive characters and send them to stdin
+func (e *ExecOverWS) pumpStdin(inw *os.File) {
 
 	done := make(chan DoneChan, 1)
 
 	if e.InputEvent != "" && e.InputCB != nil {
 
-		err := (*e.SocketIO).On(e.InputEvent, func(stdin string) {
-			in, err := e.InputCB(e, string(stdin))
+		err := (*e.SocketIO).On(e.InputEvent, func(stdin []byte) {
+			in, err := e.InputCB(e, stdin)
 			if err != nil {
 				e.logDebug("Error stdin: %s", err.Error())
 				inw.Close()
 				return
 			}
-			if _, err := inw.Write([]byte(in)); err != nil {
+			if _, err := inw.Write(in); err != nil {
 				e.logError("Error while writing to stdin: %s", err.Error())
 			}
 		})
diff --git a/golib/eows/eows-out.go b/golib/eows/eows-out.go
index 2d9bdb0..3163b2f 100644
--- a/golib/eows/eows-out.go
+++ b/golib/eows/eows-out.go
@@ -56,16 +56,15 @@ func (e *ExecOverWS) _pumper(sc *bufio.Scanner, fctCB func(s string)) {
 
 }
 
-// cmdPumpStdout is in charge to forward stdout in websocket
-func (e *ExecOverWS) cmdPumpStdout(r io.Reader, done chan struct{}) {
-
-	defer func() {
-	}()
+// pipePumpStdout is in charge to forward stdout in websocket
+func (e *ExecOverWS) pipePumpStdout(r io.Reader, done chan struct{}) {
 
 	sc := bufio.NewScanner(r)
 
 	e._pumper(sc, func(b string) {
-		e.OutputCB(e, b, "")
+		if e.OutputCB != nil {
+			e.OutputCB(e, []byte(b), []byte{})
+		}
 	})
 
 	e.logDebug("STDOUT pump exit")
@@ -77,16 +76,15 @@ func (e *ExecOverWS) cmdPumpStdout(r io.Reader, done chan struct{}) {
 	close(done)
 }
 
-// cmdPumpStderr is in charge to forward stderr in websocket
-func (e *ExecOverWS) cmdPumpStderr(r io.Reader) {
-
-	defer func() {
-	}()
+// pipePumpStderr is in charge to forward stderr in websocket
+func (e *ExecOverWS) pipePumpStderr(r io.Reader) {
 
 	sc := bufio.NewScanner(r)
 
 	e._pumper(sc, func(b string) {
-		e.OutputCB(e, "", b)
+		if e.OutputCB != nil {
+			e.OutputCB(e, []byte{}, []byte(b))
+		}
 	})
 
 	e.logDebug("STDERR pump exit")
@@ -95,3 +93,30 @@ func (e *ExecOverWS) cmdPumpStderr(r io.Reader) {
 		e.logError("stderr scan: %v", sc.Err())
 	}
 }
+
+// ptsPumpStdout is in charge to forward stdout in websocket
+// (only used when PtyMode is set)
+func (e *ExecOverWS) ptsPumpStdout(r io.Reader, done chan struct{}) {
+
+	buffer := make([]byte, 1024)
+	for {
+		n, err := r.Read(buffer)
+		if err != nil {
+			if err != io.EOF &&
+				!strings.Contains(err.Error(), "file already closed") {
+				e.logError("Error stdout read: %v", err)
+			}
+			break
+		}
+		if n == 0 {
+			continue
+		}
+		if e.OutputCB != nil {
+			e.OutputCB(e, buffer[:n], []byte{})
+		}
+	}
+
+	close(done)
+
+	e.logDebug("Eows stdout pump exited")
+}
diff --git a/golib/eows/eows.go b/golib/eows/eows.go
index 283d673..9d0b520 100644
--- a/golib/eows/eows.go
+++ b/golib/eows/eows.go
@@ -16,10 +16,10 @@ import (
 )
 
 // OnInputCB is the function callback used to receive data
-type OnInputCB func(e *ExecOverWS, stdin string) (string, error)
+type OnInputCB func(e *ExecOverWS, stdin []byte) ([]byte, error)
 
 // EmitOutputCB is the function callback used to emit data
-type EmitOutputCB func(e *ExecOverWS, stdout, stderr string)
+type EmitOutputCB func(e *ExecOverWS, stdout, stderr []byte)
 
 // EmitExitCB is the function callback used to emit exit proc code
 type EmitExitCB func(e *ExecOverWS, code int, err error)
@@ -60,7 +60,8 @@ type ExecOverWS struct {
 	UserData       *map[string]interface{} // user data passed to callbacks
 	OutSplit       SplitType               // split method to tokenize stdout/stderr
 	LineTimeSpan   int64                   // time span (only used with SplitTime or SplitLineTime)
-	PtsMode        bool                    // Allocate a pseudo-terminal (allow to execute screen-based program)
+	PtyMode        bool                    // Allocate a pseudo-terminal (allow to execute screen-based program)
+	PtyTermEcho    bool                    // Turn on/off terminal echo
 
 	// Private fields
 
@@ -84,7 +85,8 @@ func New(cmd string, args []string, so *socketio.Socket, soID, cmdID string) *Ex
 		CmdExecTimeout: -1,            // default no timeout
 		OutSplit:       SplitLineTime, // default split by line with time
 		LineTimeSpan:   500 * time.Millisecond.Nanoseconds(),
-		PtsMode:        false,
+		PtyMode:        false,
+		PtyTermEcho:    true,
 	}
 
 	cmdIDMap[cmdID] = e
@@ -114,7 +116,7 @@ func (e *ExecOverWS) Start() error {
 
 	e.procExited = false
 
-	if e.PtsMode {
+	if e.PtyMode {
 
 		e.command = exec.Command(bashArgs[0], bashArgs[1:]...)
 		e.command.Env = append(os.Environ(), e.Env...)
@@ -126,7 +128,9 @@ func (e *ExecOverWS) Start() error {
 		e.proc = e.command.Process
 
 		// Turn off terminal echo
-		e.terminalEcho(e.ptmx, false)
+		if !e.PtyTermEcho {
+			e.terminalEcho(e.ptmx, false)
+		}
 
 	} else {
 
@@ -162,15 +166,15 @@ func (e *ExecOverWS) Start() error {
 	go func() {
 		stdoutDone := make(chan struct{})
 
-		if e.PtsMode {
+		if e.PtyMode {
 			// Make sure to close the pty at the end.
 			defer e.ptmx.Close()
 
 			// Handle both stdout mixed with stderr
-			go e.cmdPumpStdout(e.ptmx, stdoutDone)
+			go e.ptsPumpStdout(e.ptmx, stdoutDone)
 
 			// Blocking function that poll input or wait for end of process
-			e.cmdPumpStdin(e.ptmx)
+			e.pumpStdin(e.ptmx)
 
 		} else {
 			// Make sure to close all pipes
@@ -182,11 +186,11 @@ func (e *ExecOverWS) Start() error {
 			defer inw.Close()
 
 			// Handle stdout + stderr
-			go e.cmdPumpStdout(outr, stdoutDone)
-			go e.cmdPumpStderr(errr)
+			go e.pipePumpStdout(outr, stdoutDone)
+			go e.pipePumpStderr(errr)
 
 			// Blocking function that poll input or wait for end of process
-			e.cmdPumpStdin(inw)
+			e.pumpStdin(inw)
 		}
 
 		if status, err := e.proc.Wait(); err == nil {
@@ -222,8 +226,8 @@ exitErr:
 
 // TerminalSetSize Set terminal size
 func (e *ExecOverWS) TerminalSetSize(rows, cols uint16) error {
-	if !e.PtsMode || e.ptmx == nil {
-		return fmt.Errorf("PtsMode not set")
+	if !e.PtyMode || e.ptmx == nil {
+		return fmt.Errorf("PtyMode not set")
 	}
 	w, err := pty.GetsizeFull(e.ptmx)
 	if err != nil {
@@ -234,8 +238,8 @@ func (e *ExecOverWS) TerminalSetSize(rows, cols uint16) error {
 
 // TerminalSetSizePos Set terminal size and position
 func (e *ExecOverWS) TerminalSetSizePos(rows, cols, x, y uint16) error {
-	if !e.PtsMode || e.ptmx == nil {
-		return fmt.Errorf("PtsMode not set")
+	if !e.PtyMode || e.ptmx == nil {
+		return fmt.Errorf("PtyMode not set")
 	}
 	winSz := pty.Winsize{Rows: rows, Cols: cols, X: x, Y: y}
 	return pty.Setsize(e.ptmx, &winSz)