From ff6bae936d097ce0b022e454f972e2c1e7eb509b Mon Sep 17 00:00:00 2001
From: topjohnwu <topjohnwu@gmail.com>
Date: Fri, 30 Sep 2016 10:52:04 +0800
Subject: [PATCH] Fix root shell racing condition

---
 .../main/java/com/topjohnwu/magisk/utils/Async.java  |  2 +-
 .../main/java/com/topjohnwu/magisk/utils/Utils.java  | 12 +++++++-----
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/app/src/main/java/com/topjohnwu/magisk/utils/Async.java b/app/src/main/java/com/topjohnwu/magisk/utils/Async.java
index eed337856..41e4c10d3 100644
--- a/app/src/main/java/com/topjohnwu/magisk/utils/Async.java
+++ b/app/src/main/java/com/topjohnwu/magisk/utils/Async.java
@@ -46,7 +46,7 @@ public class Async {
             String busybox = mContext.getApplicationInfo().dataDir + "/lib/libbusybox.so";
             String zip = mContext.getApplicationInfo().dataDir + "/lib/libzip.so";
             if (Shell.rootAccess()) {
-                if (!Utils.itemExist(toolPath)) {
+                if (!Utils.itemExist(false, toolPath)) {
                     Shell.sh(
                             "rm -rf " + toolPath,
                             "mkdir " + toolPath,
diff --git a/app/src/main/java/com/topjohnwu/magisk/utils/Utils.java b/app/src/main/java/com/topjohnwu/magisk/utils/Utils.java
index 2236f572b..4c411aedb 100644
--- a/app/src/main/java/com/topjohnwu/magisk/utils/Utils.java
+++ b/app/src/main/java/com/topjohnwu/magisk/utils/Utils.java
@@ -65,14 +65,16 @@ public class Utils {
     }
 
     public static boolean itemExist(String path) {
-        List<String> ret;
+        return itemExist(true, path);
+    }
+
+    public static boolean itemExist(boolean root, String path) {
         String command = "if [ -e " + path + " ]; then echo true; else echo false; fi";
-        if (Shell.rootAccess()) {
-            ret = Shell.su(command);
+        if (Shell.rootAccess() && root) {
+            return Boolean.parseBoolean(Shell.su(command).get(0));
         } else {
-            ret = Shell.sh(command);
+            return new File(path).exists();
         }
-        return Boolean.parseBoolean(ret.get(0));
     }
 
     public static boolean commandExists(String s) {