Add connection helper for other projects

This eases using the AIDL-Interface and is the recommended way for other
project to implement the connection.

src/org/thialfihar/android/apg/ApgService.java

@@ -4,6 +4,10 @@ import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.InputStream;
 import java.io.OutputStream;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
 
 import android.content.Intent;
 import android.os.IBinder;
@@ -20,7 +24,10 @@ public class ApgService extends Service {
 
     private final IApgService.Stub mBinder = new IApgService.Stub() {
 
-        public String encrypt_with_passphrase(String msg, String passphrase) {
+        public String encrypt_with_passphrase(List<String> args) {
+            String msg = args.remove(0);
+            String passphrase = args.remove(0);
+
             Preferences mPreferences = Preferences.getPreferences(getBaseContext(), true);
             InputStream inStream = new ByteArrayInputStream(msg.getBytes());
             InputData in = new InputData(inStream, 9999);
@@ -29,17 +36,16 @@ public class ApgService extends Service {
 
             Apg.initialize(getApplicationContext());
             try {
-                Apg.encrypt(
-                        getApplicationContext(),
-                        in,
-                        out,
+                Apg.encrypt(getApplicationContext(), // context
+                        in, // input stream
+                        out, // output stream
                         true, // armored
                         enc_keys, // encryption keys
                         0, // signature key
                         null, // signature passphrase
                         null, // progress
-                        mPreferences.getDefaultEncryptionAlgorithm(),
-                        mPreferences.getDefaultHashAlgorithm(),
+                        mPreferences.getDefaultEncryptionAlgorithm(), // encryption
+                        mPreferences.getDefaultHashAlgorithm(), // hash
                         Id.choice.compression.none, // compression
                         false, // mPreferences.getForceV3Signatures(),
                         passphrase // passPhrase
@@ -53,12 +59,13 @@ public class ApgService extends Service {
             return out.toString();
         }
 
-        public String decrypt_with_passphrase(String encrypted_msg,
-                String passphrase) {
-            InputStream inStream = new ByteArrayInputStream(encrypted_msg
-                    .getBytes());
+        public String decrypt_with_passphrase(List<String> args) {
+            String encrypted_msg = args.remove(0);
+            String passphrase = args.remove(0);
+
+            InputStream inStream = new ByteArrayInputStream(encrypted_msg.getBytes());
             InputData in = new InputData(inStream, 9999); // XXX what size in
-                                                          // second parameter?
+            // second parameter?
             OutputStream out = new ByteArrayOutputStream();
             try {
                 Apg.decrypt(getApplicationContext(), in, out, passphrase, null, // progress

src/org/thialfihar/android/apg/IApgService.aidl

@@ -1,6 +1,6 @@
 package org.thialfihar.android.apg;
 
 interface IApgService {
-    String encrypt_with_passphrase(String msg, String passphrase);
-    String decrypt_with_passphrase(String encrypted_msg, String passphrase);
+    String encrypt_with_passphrase(in List<String> params);
+    String decrypt_with_passphrase(in List<String> params);
 }

src/org/thialfihar/android/apg/utils/ApgCon.java

@@ -0,0 +1,144 @@
+package org.thialfihar.android.apg.utils;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+
+import android.content.Context;
+import android.content.ComponentName;
+import android.content.ServiceConnection;
+import android.content.Intent;
+import android.os.IBinder;
+import android.util.Log;
+
+import org.thialfihar.android.apg.IApgService;
+
+/**
+ * This class can be used by other projects to simplify connecting to the
+ * APG-Service. Kind of wrapper of for AIDL.
+ * 
+ * It is not used in this project.
+ */
+public class ApgCon {
+
+    private String TAG = "ApgCon";
+
+    private final Context mContext;
+
+    /** Remote service for decrypting and encrypting data */
+    private IApgService apgService = null;
+
+    /** Set apgService accordingly to connection status */
+    private ServiceConnection apgConnection = new ServiceConnection() {
+        public void onServiceConnected(ComponentName className, IBinder service) {
+            Log.d(TAG, "IApgService bound to apgService");
+            apgService = IApgService.Stub.asInterface(service);
+        }
+
+        public void onServiceDisconnected(ComponentName className) {
+            Log.d(TAG, "IApgService disconnected");
+            apgService = null;
+        }
+    };
+
+    /** Possible fields which are returned to the application */
+    public static enum retKey {
+        ERROR, // error enum, see below
+        ERROR_DESC, // human readable description
+        RESULT, // if everything went fine, result
+    }
+
+    public static enum error {
+        GENERIC, // no special type
+        CANNOT_BIND_TO_APG, // connection to apg service not possible
+        CALL_MISSING, // function to call not provided
+        CALL_NOT_KNOWN, // apg service does not know what to do
+    }
+
+    public ApgCon(Context ctx) {
+        Log.d(TAG, "EncryptionService created");
+        mContext = ctx;
+    }
+
+    /** try to connect to the apg service */
+    private boolean connect() {
+        Log.d(TAG, "trying to bind the apgService to context");
+
+        if (apgService != null) {
+            Log.d(TAG, "allready connected");
+            return true;
+        }
+
+        try {
+            mContext.bindService(new Intent(IApgService.class.getName()), apgConnection, Context.BIND_AUTO_CREATE);
+        } catch (Exception e) {
+            Log.d(TAG, "could not bind APG service");
+            return false;
+        }
+
+        int wait_count = 0;
+        while (apgService == null && wait_count++ < 15) {
+            Log.d(TAG, "sleeping 1 second to wait for apg");
+            android.os.SystemClock.sleep(1000);
+        }
+        ;
+
+        if (wait_count >= 15) {
+            Log.d(TAG, "slept waiting for nothing!");
+            return false;
+        }
+
+        return true;
+    }
+
+    private boolean initialize() {
+        if (apgService == null) {
+            if (!connect()) {
+                Log.d(TAG, "connection to apg service failed");
+                return false;
+            }
+        }
+        return true;
+    }
+
+    public boolean call(String function, Map<retKey, Object> return_map, String... function_params) {
+        return_map.put(retKey.ERROR, null);
+
+        if (!initialize()) {
+            return_map.put(retKey.ERROR, error.CANNOT_BIND_TO_APG);
+            return false;
+        }
+
+        if (function == null || function.length() == 0) {
+            return_map.put(retKey.ERROR, error.CALL_MISSING);
+            return false;
+        }
+
+        try {
+            List<String> params_list = Arrays.asList(function_params);
+            return_map.put(retKey.RESULT, IApgService.class.getMethod(function, List.class).invoke(apgService, params_list));
+        } catch (NoSuchMethodException e) {
+            Log.d(TAG, e.getMessage());
+            return_map.put(retKey.ERROR, error.CALL_NOT_KNOWN);
+            return_map.put(retKey.ERROR_DESC, e.getMessage());
+            return false;
+        } catch (Exception e) {
+            Log.d(TAG, e.getMessage());
+            return_map.put(retKey.ERROR, error.GENERIC);
+            return_map.put(retKey.ERROR_DESC, e.getMessage());
+            return false;
+        }
+
+        return true;
+
+    }
+
+    private void disconnect() {
+        Log.d(TAG, "disconnecting apgService");
+        if (apgService != null) {
+            mContext.unbindService(apgConnection);
+            apgService = null;
+        }
+    }
+
+}