MTP: Skip runtime thumbnail generation for Android Host

Android Host is not capable to deal with the long processing time for
runtime thumbnail generation.
Skip runtime thumbnail generation for Android Host
but keep no impact to other Host

Bug: 188752500
Test: atest MtpTests
Test: atest MtpServerTest
Test: atest MtpServiceTests
Test: manual test on Windows 10 File Explorer
Test: manual test on Android Host Files App
Change-Id: I24ed3bb29c5a6912398a9e00e7748fd406cf6a64

1 files changed, 35 insertions, 2 deletions

diff --git a/media/java/android/mtp/MtpDatabase.java b/media/java/android/mtp/MtpDatabase.java
index 860d88afe4a2..d8f48c2cf0c6 100755
--- a/media/java/android/mtp/MtpDatabase.java
+++ b/media/java/android/mtp/MtpDatabase.java
@@ -101,6 +101,8 @@ public class MtpDatabase implements AutoCloseable {
     private int mBatteryLevel;
     private int mBatteryScale;
     private int mDeviceType;
+    private String mHostType;
+    private boolean mSkipThumbForHost = false;
 
     private MtpServer mServer;
     private MtpStorageManager mManager;
@@ -192,6 +194,7 @@ public class MtpDatabase implements AutoCloseable {
             MtpConstants.DEVICE_PROPERTY_IMAGE_SIZE,
             MtpConstants.DEVICE_PROPERTY_BATTERY_LEVEL,
             MtpConstants.DEVICE_PROPERTY_PERCEIVED_DEVICE_TYPE,
+            MtpConstants.DEVICE_PROPERTY_SESSION_INITIATOR_VERSION_INFO,
     };
 
     @VisibleForNative
@@ -408,6 +411,8 @@ public class MtpDatabase implements AutoCloseable {
             }
             context.deleteDatabase(devicePropertiesName);
         }
+        mHostType = "";
+        mSkipThumbForHost = false;
     }
 
     @VisibleForNative
@@ -672,12 +677,24 @@ public class MtpDatabase implements AutoCloseable {
 
     @VisibleForNative
     private int getDeviceProperty(int property, long[] outIntValue, char[] outStringValue) {
+        int length;
+        String value;
+
         switch (property) {
             case MtpConstants.DEVICE_PROPERTY_SYNCHRONIZATION_PARTNER:
             case MtpConstants.DEVICE_PROPERTY_DEVICE_FRIENDLY_NAME:
                 // writable string properties kept in shared preferences
-                String value = mDeviceProperties.getString(Integer.toString(property), "");
-                int length = value.length();
+                value = mDeviceProperties.getString(Integer.toString(property), "");
+                length = value.length();
+                if (length > 255) {
+                    length = 255;
+                }
+                value.getChars(0, length, outStringValue, 0);
+                outStringValue[length] = 0;
+                return MtpConstants.RESPONSE_OK;
+            case MtpConstants.DEVICE_PROPERTY_SESSION_INITIATOR_VERSION_INFO:
+                value = mHostType;
+                length = value.length();
                 if (length > 255) {
                     length = 255;
                 }
@@ -717,6 +734,14 @@ public class MtpDatabase implements AutoCloseable {
                 e.putString(Integer.toString(property), stringValue);
                 return (e.commit() ? MtpConstants.RESPONSE_OK
                         : MtpConstants.RESPONSE_GENERAL_ERROR);
+            case MtpConstants.DEVICE_PROPERTY_SESSION_INITIATOR_VERSION_INFO:
+                mHostType = stringValue;
+                if (stringValue.startsWith("Android/")) {
+                    Log.d(TAG, "setDeviceProperty." + Integer.toHexString(property)
+                            + "=" + stringValue);
+                    mSkipThumbForHost = true;
+                }
+                return MtpConstants.RESPONSE_OK;
         }
 
         return MtpConstants.RESPONSE_DEVICE_PROP_NOT_SUPPORTED;
@@ -838,6 +863,10 @@ public class MtpDatabase implements AutoCloseable {
                     outLongs[0] = thumbOffsetAndSize != null ? thumbOffsetAndSize[1] : 0;
                     outLongs[1] = exif.getAttributeInt(ExifInterface.TAG_PIXEL_X_DIMENSION, 0);
                     outLongs[2] = exif.getAttributeInt(ExifInterface.TAG_PIXEL_Y_DIMENSION, 0);
+                    if (mSkipThumbForHost) {
+                        Log.d(TAG, "getThumbnailInfo: Skip runtime thumbnail.");
+                        return true;
+                    }
                     if (exif.getThumbnailRange() != null) {
                         if ((outLongs[0] == 0) || (outLongs[1] == 0) || (outLongs[2] == 0)) {
                             Log.d(TAG, "getThumbnailInfo: check thumb info:"
@@ -880,6 +909,10 @@ public class MtpDatabase implements AutoCloseable {
                 try {
                     ExifInterface exif = new ExifInterface(path);
 
+                    if (mSkipThumbForHost) {
+                        Log.d(TAG, "getThumbnailData: Skip runtime thumbnail.");
+                        return exif.getThumbnail();
+                    }
                     if (exif.getThumbnailRange() != null)
                         return exif.getThumbnail();
                 } catch (IOException e) {