use mutexes on escape code

vendor/github.com/jesseduffield/gocui/escape.go

@@ -5,8 +5,10 @@
 package gocui
 
 import (
-	"github.com/go-errors/errors"
 	"strconv"
+	"sync"
+
+	"github.com/go-errors/errors"
 )
 
 type escapeInterpreter struct {
@@ -15,6 +17,7 @@ type escapeInterpreter struct {
 	csiParam               []string
 	curFgColor, curBgColor Attribute
 	mode                   OutputMode
+	mutex                  sync.Mutex
 }
 
 type escapeState int
@@ -34,6 +37,9 @@ var (
 
 // runes in case of error will output the non-parsed runes as a string.
 func (ei *escapeInterpreter) runes() []rune {
+	ei.mutex.Lock()
+	defer ei.mutex.Unlock()
+
 	switch ei.state {
 	case stateNone:
 		return []rune{0x1b}
@@ -66,6 +72,9 @@ func newEscapeInterpreter(mode OutputMode) *escapeInterpreter {
 
 // reset sets the escapeInterpreter in initial state.
 func (ei *escapeInterpreter) reset() {
+	ei.mutex.Lock()
+	defer ei.mutex.Unlock()
+
 	ei.state = stateNone
 	ei.curFgColor = ColorDefault
 	ei.curBgColor = ColorDefault
@@ -76,6 +85,9 @@ func (ei *escapeInterpreter) reset() {
 // of an escape sequence, and as such should not be printed verbatim. Otherwise,
 // it's not an escape sequence.
 func (ei *escapeInterpreter) parseOne(ch rune) (isEscape bool, err error) {
+	ei.mutex.Lock()
+	defer ei.mutex.Unlock()
+
 	// Sanity checks
 	if len(ei.csiParam) > 20 {
 		return false, errCSITooLong
@@ -179,6 +191,9 @@ func (ei *escapeInterpreter) outputNormal() error {
 //   0x11 - 0xe8: 216 different colors
 //   0xe9 - 0x1ff: 24 different shades of grey
 func (ei *escapeInterpreter) output256() error {
+	ei.mutex.Lock()
+	defer ei.mutex.Unlock()
+
 	if len(ei.csiParam) < 3 {
 		return ei.outputNormal()
 	}