Merge pull request #1764 from restic/fix-display

Fix display

internal/ui/backup.go

@@ -150,16 +150,18 @@ func (b *Backup) update(total, processed counter, errors uint, currentFiles map[
 			processed.Files, formatBytes(processed.Bytes), errors,
 		)
 	} else {
-		var eta string
+		var eta, percent string
 
 		if secs > 0 && processed.Bytes < total.Bytes {
 			eta = fmt.Sprintf(" ETA %s", formatSeconds(secs))
+			percent = formatPercent(processed.Bytes, total.Bytes)
+			percent += "  "
 		}
 
 		// include totals
 		status = fmt.Sprintf("[%s] %s%v files %s, total %v files %v, %d errors%s",
 			formatDuration(time.Since(b.start)),
-			formatPercent(processed.Bytes, total.Bytes),
+			percent,
 			processed.Files,
 			formatBytes(processed.Bytes),
 			total.Files,

internal/ui/termstatus/status.go

@@ -21,10 +21,14 @@ type Terminal struct {
 	msg             chan message
 	status          chan status
 	canUpdateStatus bool
-	clearLines      clearLinesFunc
-}
 
-type clearLinesFunc func(wr io.Writer, fd uintptr, n int)
+	// will be closed when the goroutine which runs Run() terminates, so it'll
+	// yield a default value immediately
+	closed chan struct{}
+
+	clearCurrentLine func(io.Writer, uintptr)
+	moveCursorUp     func(io.Writer, uintptr, int)
+}
 
 type message struct {
 	line string
@@ -53,6 +57,7 @@ func New(wr io.Writer, errWriter io.Writer, disableStatus bool) *Terminal {
 		buf:       bytes.NewBuffer(nil),
 		msg:       make(chan message),
 		status:    make(chan status),
+		closed:    make(chan struct{}),
 	}
 
 	if disableStatus {
@@ -63,7 +68,8 @@ func New(wr io.Writer, errWriter io.Writer, disableStatus bool) *Terminal {
 		// only use the fancy status code when we're running on a real terminal.
 		t.canUpdateStatus = true
 		t.fd = d.Fd()
-		t.clearLines = clearLines(wr, t.fd)
+		t.clearCurrentLine = clearCurrentLine(wr, t.fd)
+		t.moveCursorUp = moveCursorUp(wr, t.fd)
 	}
 
 	return t
@@ -72,6 +78,7 @@ func New(wr io.Writer, errWriter io.Writer, disableStatus bool) *Terminal {
 // Run updates the screen. It should be run in a separate goroutine. When
 // ctx is cancelled, the status lines are cleanly removed.
 func (t *Terminal) Run(ctx context.Context) {
+	defer close(t.closed)
 	if t.canUpdateStatus {
 		t.run(ctx)
 		return
@@ -80,23 +87,13 @@ func (t *Terminal) Run(ctx context.Context) {
 	t.runWithoutStatus(ctx)
 }
 
-func countLines(buf []byte) int {
-	lines := 0
-	sc := bufio.NewScanner(bytes.NewReader(buf))
-	for sc.Scan() {
-		lines++
-	}
-	return lines
-}
-
 type stringWriter interface {
 	WriteString(string) (int, error)
 }
 
 // run listens on the channels and updates the terminal screen.
 func (t *Terminal) run(ctx context.Context) {
-	statusBuf := bytes.NewBuffer(nil)
-	statusLines := 0
+	var status []string
 	for {
 		select {
 		case <-ctx.Done():
@@ -104,12 +101,7 @@ func (t *Terminal) run(ctx context.Context) {
 				// ignore all messages, do nothing, we are in the background process group
 				continue
 			}
-			t.undoStatus(statusLines)
-
-			err := t.wr.Flush()
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "flush failed: %v\n", err)
-			}
+			t.undoStatus(len(status))
 
 			return
 
@@ -118,14 +110,14 @@ func (t *Terminal) run(ctx context.Context) {
 				// ignore all messages, do nothing, we are in the background process group
 				continue
 			}
-			t.undoStatus(statusLines)
+			t.clearCurrentLine(t.wr, t.fd)
 
 			var dst io.Writer
 			if msg.err {
 				dst = t.errWriter
 
 				// assume t.wr and t.errWriter are different, so we need to
-				// flush the removal of the status lines first.
+				// flush clearing the current line
 				err := t.wr.Flush()
 				if err != nil {
 					fmt.Fprintf(os.Stderr, "flush failed: %v\n", err)
@@ -146,10 +138,7 @@ func (t *Terminal) run(ctx context.Context) {
 				continue
 			}
 
-			_, err = t.wr.Write(statusBuf.Bytes())
-			if err != nil {
-				fmt.Fprintf(os.Stderr, "write failed: %v\n", err)
-			}
+			t.writeStatus(status)
 
 			err = t.wr.Flush()
 			if err != nil {
@@ -161,24 +150,37 @@ func (t *Terminal) run(ctx context.Context) {
 				// ignore all messages, do nothing, we are in the background process group
 				continue
 			}
-			t.undoStatus(statusLines)
 
-			statusBuf.Reset()
-			for _, line := range stat.lines {
-				statusBuf.WriteString(line)
+			status = status[:0]
+			status = append(status, stat.lines...)
+			t.writeStatus(status)
+		}
+	}
 }
-			statusLines = len(stat.lines)
 
-			_, err := t.wr.Write(statusBuf.Bytes())
+func (t *Terminal) writeStatus(status []string) {
+	for _, line := range status {
+		t.clearCurrentLine(t.wr, t.fd)
+
+		_, err := t.wr.WriteString(line)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "write failed: %v\n", err)
 		}
 
+		// flush is needed so that the current line is updated
 		err = t.wr.Flush()
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "flush failed: %v\n", err)
 		}
 	}
+
+	if len(status) > 0 {
+		t.moveCursorUp(t.wr, t.fd, len(status)-1)
+	}
+
+	err := t.wr.Flush()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "flush failed: %v\n", err)
 	}
 }
 
@@ -227,12 +229,27 @@ func (t *Terminal) runWithoutStatus(ctx context.Context) {
 }
 
 func (t *Terminal) undoStatus(lines int) {
-	if lines == 0 {
-		return
+	for i := 0; i < lines; i++ {
+		t.clearCurrentLine(t.wr, t.fd)
+
+		_, err := t.wr.WriteRune('\n')
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "write failed: %v\n", err)
 		}
 
-	lines--
-	t.clearLines(t.wr, t.fd, lines)
+		// flush is needed so that the current line is updated
+		err = t.wr.Flush()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "flush failed: %v\n", err)
+		}
+	}
+
+	t.moveCursorUp(t.wr, t.fd, lines)
+
+	err := t.wr.Flush()
+	if err != nil {
+		fmt.Fprintf(os.Stderr, "flush failed: %v\n", err)
+	}
 }
 
 // Print writes a line to the terminal.
@@ -242,7 +259,10 @@ func (t *Terminal) Print(line string) {
 		line += "\n"
 	}
 
-	t.msg <- message{line: line}
+	select {
+	case t.msg <- message{line: line}:
+	case <-t.closed:
+	}
 }
 
 // Printf uses fmt.Sprintf to write a line to the terminal.
@@ -258,7 +278,10 @@ func (t *Terminal) Error(line string) {
 		line += "\n"
 	}
 
-	t.msg <- message{line: line, err: true}
+	select {
+	case t.msg <- message{line: line, err: true}:
+	case <-t.closed:
+	}
 }
 
 // Errorf uses fmt.Sprintf to write an error line to the terminal.
@@ -294,5 +317,8 @@ func (t *Terminal) SetStatus(lines []string) {
 	last := len(lines) - 1
 	lines[last] = strings.TrimRight(lines[last], "\n")
 
-	t.status <- status{lines: lines}
+	select {
+	case t.status <- status{lines: lines}:
+	case <-t.closed:
+	}
 }

internal/ui/termstatus/terminal_posix.go

@@ -1,33 +1,36 @@
 package termstatus
 
 import (
+	"bytes"
 	"fmt"
 	"io"
 	"os"
 )
 
 const (
-	posixMoveCursorHome = "\r"
-	posixMoveCursorUp   = "\x1b[1A"
-	posixClearLine      = "\x1b[2K"
+	posixControlMoveCursorHome = "\r"
+	posixControlMoveCursorUp   = "\x1b[1A"
+	posixControlClearLine      = "\x1b[2K"
 )
 
-// posixClearLines will clear the current line and the n lines above.
-// Afterwards the cursor is positioned at the start of the first cleared line.
-func posixClearLines(wr io.Writer, fd uintptr, n int) {
+// posixClearCurrentLine removes all characters from the current line and resets the
+// cursor position to the first column.
+func posixClearCurrentLine(wr io.Writer, fd uintptr) {
 	// clear current line
-	_, err := wr.Write([]byte(posixMoveCursorHome + posixClearLine))
+	_, err := wr.Write([]byte(posixControlMoveCursorHome + posixControlClearLine))
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "write failed: %v\n", err)
 		return
 	}
+}
 
-	for ; n > 0; n-- {
-		// clear current line and move on line up
-		_, err := wr.Write([]byte(posixMoveCursorUp + posixClearLine))
+// posixMoveCursorUp moves the cursor to the line n lines above the current one.
+func posixMoveCursorUp(wr io.Writer, fd uintptr, n int) {
+	data := []byte(posixControlMoveCursorHome)
+	data = append(data, bytes.Repeat([]byte(posixControlMoveCursorUp), n)...)
+	_, err := wr.Write(data)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "write failed: %v\n", err)
 		return
 	}
 }
-}

internal/ui/termstatus/terminal_unix.go

@@ -10,10 +10,15 @@ import (
 	isatty "github.com/mattn/go-isatty"
 )
 
-// clearLines will clear the current line and the n lines above. Afterwards the
-// cursor is positioned at the start of the first cleared line.
-func clearLines(wr io.Writer, fd uintptr) clearLinesFunc {
-	return posixClearLines
+// clearCurrentLine removes all characters from the current line and resets the
+// cursor position to the first column.
+func clearCurrentLine(wr io.Writer, fd uintptr) func(io.Writer, uintptr) {
+	return posixClearCurrentLine
+}
+
+// moveCursorUp moves the cursor to the line n lines above the current one.
+func moveCursorUp(wr io.Writer, fd uintptr) func(io.Writer, uintptr, int) {
+	return posixMoveCursorUp
 }
 
 // canUpdateStatus returns true if status lines can be printed, the process

internal/ui/termstatus/terminal_windows.go

@@ -8,11 +8,29 @@ import (
 	"unsafe"
 )
 
-// clearLines clears the current line and n lines above it.
-func clearLines(wr io.Writer, fd uintptr) clearLinesFunc {
+// clearCurrentLine removes all characters from the current line and resets the
+// cursor position to the first column.
+func clearCurrentLine(wr io.Writer, fd uintptr) func(io.Writer, uintptr) {
 	// easy case, the terminal is cmd or psh, without redirection
 	if isWindowsTerminal(fd) {
-		return windowsClearLines
+		return windowsClearCurrentLine
+	}
+
+	// check if the output file type is a pipe (0x0003)
+	if getFileType(fd) != fileTypePipe {
+		// return empty func, update state is not possible on this terminal
+		return func(io.Writer, uintptr) {}
+	}
+
+	// assume we're running in mintty/cygwin
+	return posixClearCurrentLine
+}
+
+// moveCursorUp moves the cursor to the line n lines above the current one.
+func moveCursorUp(wr io.Writer, fd uintptr) func(io.Writer, uintptr, int) {
+	// easy case, the terminal is cmd or psh, without redirection
+	if isWindowsTerminal(fd) {
+		return windowsMoveCursorUp
 	}
 
 	// check if the output file type is a pipe (0x0003)
@@ -22,7 +40,7 @@ func clearLines(wr io.Writer, fd uintptr) clearLinesFunc {
 	}
 
 	// assume we're running in mintty/cygwin
-	return posixClearLines
+	return posixMoveCursorUp
 }
 
 var kernel32 = syscall.NewLazyDLL("kernel32.dll")
@@ -60,16 +78,16 @@ type (
 	}
 )
 
-// windowsClearLines clears the current line and n lines above it.
-func windowsClearLines(wr io.Writer, fd uintptr, n int) {
+// windowsClearCurrentLine removes all characters from the current line and
+// resets the cursor position to the first column.
+func windowsClearCurrentLine(wr io.Writer, fd uintptr) {
 	var info consoleScreenBufferInfo
 	procGetConsoleScreenBufferInfo.Call(fd, uintptr(unsafe.Pointer(&info)))
 
-	for i := 0; i <= n; i++ {
 	// clear the line
 	cursor := coord{
 		x: info.window.left,
-			y: info.cursorPosition.y - short(i),
+		y: info.cursorPosition.y,
 	}
 	var count, w dword
 	count = dword(info.size.x)
@@ -77,6 +95,11 @@ func windowsClearLines(wr io.Writer, fd uintptr, n int) {
 	procFillConsoleOutputCharacter.Call(fd, uintptr(' '), uintptr(count), *(*uintptr)(unsafe.Pointer(&cursor)), uintptr(unsafe.Pointer(&w)))
 }
 
+// windowsMoveCursorUp moves the cursor to the line n lines above the current one.
+func windowsMoveCursorUp(wr io.Writer, fd uintptr, n int) {
+	var info consoleScreenBufferInfo
+	procGetConsoleScreenBufferInfo.Call(fd, uintptr(unsafe.Pointer(&info)))
+
 	// move cursor up by n lines and to the first column
 	info.cursorPosition.y -= short(n)
 	info.cursorPosition.x = 0