From 06d596e780031331302ac7b8b4a85a74f1e668f4 Mon Sep 17 00:00:00 2001
From: Zachary Yedidia <zyedidia@gmail.com>
Date: Tue, 28 Aug 2018 14:24:59 -0400
Subject: [PATCH] Synchronize screen

---
 cmd/micro/action/actions_posix.go | 11 ++---------
 cmd/micro/micro.go                |  3 ++-
 cmd/micro/screen/screen.go        | 31 +++++++++++++++++++++++++++++--
 cmd/micro/util/message.go         | 10 ++--------
 4 files changed, 35 insertions(+), 20 deletions(-)

diff --git a/cmd/micro/action/actions_posix.go b/cmd/micro/action/actions_posix.go
index 8981685f..46eac8af 100644
--- a/cmd/micro/action/actions_posix.go
+++ b/cmd/micro/action/actions_posix.go
@@ -13,12 +13,7 @@ import (
 // This only works on linux and has no default binding.
 // This code was adapted from the suspend code in nsf/godit
 func (*BufHandler) Suspend() bool {
-	screenWasNil := screen.Screen == nil
-
-	if !screenWasNil {
-		screen.Screen.Fini()
-		screen.Screen = nil
-	}
+	screen.TempFini()
 
 	// suspend the process
 	pid := syscall.Getpid()
@@ -27,9 +22,7 @@ func (*BufHandler) Suspend() bool {
 		util.TermMessage(err)
 	}
 
-	if !screenWasNil {
-		screen.Init()
-	}
+	screen.TempStart()
 
 	return false
 }
diff --git a/cmd/micro/micro.go b/cmd/micro/micro.go
index 070c860d..05d720ce 100644
--- a/cmd/micro/micro.go
+++ b/cmd/micro/micro.go
@@ -144,8 +144,9 @@ func main() {
 	go func() {
 		events = make(chan tcell.Event)
 		for {
-			// TODO: fix race condition with screen.Screen = nil
+			screen.Lock()
 			events <- screen.Screen.PollEvent()
+			screen.Unlock()
 		}
 	}()
 
diff --git a/cmd/micro/screen/screen.go b/cmd/micro/screen/screen.go
index 3653da32..3cba43f5 100644
--- a/cmd/micro/screen/screen.go
+++ b/cmd/micro/screen/screen.go
@@ -3,6 +3,7 @@ package screen
 import (
 	"fmt"
 	"os"
+	"sync"
 
 	"github.com/zyedidia/micro/cmd/micro/config"
 	"github.com/zyedidia/micro/cmd/micro/terminfo"
@@ -10,6 +11,34 @@ import (
 )
 
 var Screen tcell.Screen
+var lock sync.Mutex
+
+func Lock() {
+	lock.Lock()
+}
+
+func Unlock() {
+	lock.Unlock()
+}
+
+var screenWasNil bool
+
+func TempFini() {
+	screenWasNil := Screen == nil
+
+	if !screenWasNil {
+		Lock()
+		Screen.Fini()
+		Screen = nil
+	}
+}
+
+func TempStart() {
+	if !screenWasNil {
+		Init()
+		Unlock()
+	}
+}
 
 // Init creates and initializes the tcell screen
 func Init() {
@@ -64,6 +93,4 @@ func Init() {
 	}
 
 	os.Setenv("TCELLDB", tcelldb)
-
-	// Screen.SetStyle(defStyle)
 }
diff --git a/cmd/micro/util/message.go b/cmd/micro/util/message.go
index 589dbbcd..2a1ddce1 100644
--- a/cmd/micro/util/message.go
+++ b/cmd/micro/util/message.go
@@ -16,11 +16,7 @@ import (
 // This will write the message, and wait for the user
 // to press and key to continue
 func TermMessage(msg ...interface{}) {
-	screenWasNil := screen.Screen == nil
-	if !screenWasNil {
-		screen.Screen.Fini()
-		screen.Screen = nil
-	}
+	screen.TempFini()
 
 	fmt.Println(msg...)
 	fmt.Print("\nPress enter to continue")
@@ -28,9 +24,7 @@ func TermMessage(msg ...interface{}) {
 	reader := bufio.NewReader(os.Stdin)
 	reader.ReadString('\n')
 
-	if !screenWasNil {
-		screen.Init()
-	}
+	screen.TempStart()
 }
 
 // TermError sends an error to the user in the terminal. Like TermMessage except formatted