Merge "Revert "Remove a misleading "flush" function.""

core/java/android/bluetooth/BluetoothOutputStream.java

@@ -75,4 +75,16 @@ import java.io.OutputStream;
         }
         mSocket.write(b, offset, count);
     }
+
+    /**
+     * Wait until the data in sending queue is emptied. A polling version
+     * for flush implementation. Use it to ensure the writing data afterwards will
+     * be packed in the new RFCOMM frame.
+     *
+     * @throws IOException if an i/o error occurs.
+     * @since Android 4.2.3
+     */
+    public void flush() throws IOException {
+        mSocket.flush();
+    }
 }

core/java/android/bluetooth/BluetoothSocket.java

@@ -515,6 +515,20 @@ public final class BluetoothSocket implements Closeable {
         return mSocketIS.available();
     }
 
+    /**
+     * Wait until the data in sending queue is emptied. A polling version
+     * for flush implementation. Used to ensure the writing data afterwards will
+     * be packed in new RFCOMM frame.
+     *
+     * @throws IOException if an i/o error occurs.
+     */
+    @UnsupportedAppUsage
+    /*package*/ void flush() throws IOException {
+        if (mSocketOS == null) throw new IOException("flush is called on null OutputStream");
+        if (VDBG) Log.d(TAG, "flush: " + mSocketOS);
+        mSocketOS.flush();
+    }
+
     /*package*/ int read(byte[] b, int offset, int length) throws IOException {
         int ret = 0;
         if (VDBG) Log.d(TAG, "read in:  " + mSocketIS + " len: " + length);

core/java/android/net/LocalSocketImpl.java

@@ -157,6 +157,40 @@ class LocalSocketImpl
                 write_native(b, myFd);
             }
         }
+
+        /**
+         * Wait until the data in sending queue is emptied. A polling version
+         * for flush implementation.
+         * @throws IOException
+         *             if an i/o error occurs.
+         */
+        @Override
+        public void flush() throws IOException {
+            FileDescriptor myFd = fd;
+            if (myFd == null) throw new IOException("socket closed");
+
+            // Loop until the output buffer is empty.
+            Int32Ref pending = new Int32Ref(0);
+            while (true) {
+                try {
+                    // See linux/net/unix/af_unix.c
+                    Os.ioctlInt(myFd, OsConstants.TIOCOUTQ, pending);
+                } catch (ErrnoException e) {
+                    throw e.rethrowAsIOException();
+                }
+
+                if (pending.value <= 0) {
+                    // The output buffer is empty.
+                    break;
+                }
+
+                try {
+                    Thread.sleep(10);
+                } catch (InterruptedException ie) {
+                    break;
+                }
+            }
+        }
     }
 
     private native int read_native(FileDescriptor fd) throws IOException;

services/core/java/com/android/server/RecoverySystemService.java

@@ -25,12 +25,15 @@ import android.os.PowerManager;
 import android.os.RecoverySystem;
 import android.os.RemoteException;
 import android.os.SystemProperties;
+import android.system.ErrnoException;
+import android.system.Os;
 import android.util.Slog;
 
 import libcore.io.IoUtils;
 
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
+import java.io.File;
 import java.io.FileWriter;
 import java.io.IOException;
 
@@ -285,6 +288,7 @@ public final class RecoverySystemService extends SystemService {
                     byte[] cmdUtf8 = command.getBytes("UTF-8");
                     dos.writeInt(cmdUtf8.length);
                     dos.write(cmdUtf8, 0, cmdUtf8.length);
+                    dos.flush();
                 }
 
                 // Read the status from the socket.

services/core/java/com/android/server/connectivity/Vpn.java

@@ -2082,6 +2082,7 @@ public class Vpn {
                     }
                     out.write(0xFF);
                     out.write(0xFF);
+                    out.flush();
 
                     // Wait for End-of-File.
                     InputStream in = mSockets[i].getInputStream();