Add Android app from Yue

[~andy/csm213a-hw] / syc / src / com / example / sycapp / SerialPort.java

diff --git a/syc/src/com/example/sycapp/SerialPort.java b/syc/src/com/example/sycapp/SerialPort.java
new file mode 100644 (file)
index 0000000..e280a2a
--- /dev/null
+++ b/syc/src/com/example/sycapp/SerialPort.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright 2009 Cedric Priscal
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License. 
+ */
+
+package com.example.sycapp;
+
+import java.io.File;
+import java.io.FileDescriptor;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+import android.util.Log;
+
+public class SerialPort {
+
+       private static final String TAG = "SerialPort";
+
+       /*
+        * Do not remove or rename the field mFd: it is used by native method close();
+        */
+       private FileDescriptor mFd;
+       private FileInputStream mFileInputStream;
+       private FileOutputStream mFileOutputStream;
+
+       public SerialPort(File device, int baudrate, int flags) throws SecurityException, IOException {
+
+               /* Check access permission */
+               if (!device.canRead() || !device.canWrite()) {
+                       try {
+                               /* Missing read/write permission, trying to chmod the file */
+                               Process su;
+                               su = Runtime.getRuntime().exec("/system/bin/su");
+                               String cmd = "chmod 666 " + device.getAbsolutePath() + "\n"
+                                               + "exit\n";
+                               su.getOutputStream().write(cmd.getBytes());
+                               if ((su.waitFor() != 0) || !device.canRead()
+                                               || !device.canWrite()) {
+                                       throw new SecurityException();
+                               }
+                       } catch (Exception e) {
+                               e.printStackTrace();
+                               throw new SecurityException();
+                       }
+               }
+
+               mFd = open(device.getAbsolutePath(), baudrate, flags);
+               if (mFd == null) {
+                       Log.e(TAG, "native open returns null");
+                       throw new IOException();
+               }
+               mFileInputStream = new FileInputStream(mFd);
+               mFileOutputStream = new FileOutputStream(mFd);
+       }
+
+       // Getters and setters
+       public InputStream getInputStream() {
+               return mFileInputStream;
+       }
+
+       public OutputStream getOutputStream() {
+               return mFileOutputStream;
+       }
+
+       // JNI
+       private native static FileDescriptor open(String path, int baudrate, int flags);
+       public native void close();
+       static {
+               System.loadLibrary("serial_port");
+       }
+}