From b7a941a3b76dbd12e6de201c547bc0563d92e505 Mon Sep 17 00:00:00 2001
From: SeungHoon Han <senicy.han@samsung.com>
Date: Tue, 2 Aug 2022 19:39:50 +0900
Subject: [PATCH] added fallback getting displayInfo when displayInfo is null

---
 .../main/java/com/genymobile/scrcpy/Command.java |  8 ++++----
 .../scrcpy/wrappers/DisplayManager.java          | 16 ++++++++++++++++
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/server/src/main/java/com/genymobile/scrcpy/Command.java b/server/src/main/java/com/genymobile/scrcpy/Command.java
index 0ef976a66c..8cf6c4b117 100644
--- a/server/src/main/java/com/genymobile/scrcpy/Command.java
+++ b/server/src/main/java/com/genymobile/scrcpy/Command.java
@@ -18,16 +18,16 @@ public static void exec(String... cmd) throws IOException, InterruptedException
     }
 
     public static String execReadLine(String... cmd) throws IOException, InterruptedException {
-        String result = null;
+        StringBuilder result = new StringBuilder();
         Process process = Runtime.getRuntime().exec(cmd);
         Scanner scanner = new Scanner(process.getInputStream());
-        if (scanner.hasNextLine()) {
-            result = scanner.nextLine();
+        while (scanner.hasNextLine()) {
+            result.append(scanner.nextLine()).append("\n");
         }
         int exitCode = process.waitFor();
         if (exitCode != 0) {
             throw new IOException("Command " + Arrays.toString(cmd) + " returned with value " + exitCode);
         }
-        return result;
+        return result.toString();
     }
 }
diff --git a/server/src/main/java/com/genymobile/scrcpy/wrappers/DisplayManager.java b/server/src/main/java/com/genymobile/scrcpy/wrappers/DisplayManager.java
index 3f4f897dfa..cd920d951b 100644
--- a/server/src/main/java/com/genymobile/scrcpy/wrappers/DisplayManager.java
+++ b/server/src/main/java/com/genymobile/scrcpy/wrappers/DisplayManager.java
@@ -1,8 +1,12 @@
 package com.genymobile.scrcpy.wrappers;
 
+import com.genymobile.scrcpy.Command;
 import com.genymobile.scrcpy.DisplayInfo;
 import com.genymobile.scrcpy.Size;
 
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
 public final class DisplayManager {
     private final Object manager; // instance of hidden class android.hardware.display.DisplayManagerGlobal
 
@@ -14,6 +18,18 @@ public DisplayInfo getDisplayInfo(int displayId) {
         try {
             Object displayInfo = manager.getClass().getMethod("getDisplayInfo", int.class).invoke(manager, displayId);
             if (displayInfo == null) {
+                // fallback when displayInfo is null
+                String dumpDisplay = Command.execReadLine("dumpsys", "display");
+                Pattern regex = Pattern.compile("(mBaseDisplayInfo=DisplayInfo\\{\".+?\", displayId " + displayId +
+                        ")(.+)(, real )([0-9]+) x ([0-9]+)(.+)(, rotation )([0-9]+)(.+)(, layerStack )([0-9]+)(.+)");
+                Matcher m = regex.matcher(dumpDisplay);
+                if (m.find()) {
+                    int width = Integer.parseInt(m.group(4));
+                    int height = Integer.parseInt(m.group(5));
+                    int rotation = Integer.parseInt(m.group(8));
+                    int layerStack = Integer.parseInt(m.group(11));
+                    return new DisplayInfo(displayId, new Size(width, height), rotation, layerStack, 0);
+                }
                 return null;
             }
             Class<?> cls = displayInfo.getClass();