Pull cacheinvalidations code directory into chromium repo.

third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/android2/channel/AndroidChannelPreferences.java

Index: third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/android2/channel/AndroidChannelPreferences.java
diff --git a/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/android2/channel/AndroidChannelPreferences.java b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/android2/channel/AndroidChannelPreferences.java
new file mode 100644
index 0000000000000000000000000000000000000000..1dc4c92dea2b2ffc910e4464f83887ed91af3d1c
--- /dev/null
+++ b/third_party/cacheinvalidation/src/java/com/google/ipc/invalidation/ticl/android2/channel/AndroidChannelPreferences.java
@@ -0,0 +1,106 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * 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.google.ipc.invalidation.ticl.android2.channel;
+
+import com.google.ipc.invalidation.external.client.SystemResources.Logger;
+import com.google.ipc.invalidation.external.client.android.service.AndroidLogger;
+import com.google.ipc.invalidation.ticl.android2.channel.AndroidChannelConstants.C2dmConstants;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.util.Base64;
+
+
+/** Accessor class for shared preference entries used by the channel. */
+ public class AndroidChannelPreferences {
+  /** Name of the preferences in which channel preferences are stored. */
+  private static final String PREFERENCES_NAME = "com.google.ipc.invalidation.gcmchannel";
+
+  /**
+   * Preferences entry used to buffer the last message sent by the Ticl in the case where a GCM
+   * registration id is not currently available.
+   */
+  private static final String BUFFERED_MSG_PREF = "buffered-msg";
+
+  private static final Logger logger = AndroidLogger.forTag("ChannelPrefs");
+
+  /** Sets the token echoed on subsequent HTTP requests. */
+  static void setEchoToken(Context context, String token) {
+    SharedPreferences.Editor editor = getPreferences(context).edit();
+
+    // This might fail, but at worst it just means we lose an echo token; the channel
+    // needs to be able to handle that anyway since it can never assume an echo token
+    // makes it to the client (since the channel can drop messages).
+    editor.putString(C2dmConstants.ECHO_PARAM, token);
+    if (!editor.commit()) {
+      logger.warning("Failed writing shared preferences for: setEchoToken");
+    }
+  }
+
+  /** Returns the echo token that should be included on HTTP requests. */
+  
+  public static String getEchoToken(Context context) {
+    return getPreferences(context).getString(C2dmConstants.ECHO_PARAM, null);
+  }
+
+  /** Buffers the last message sent by the Ticl. Overwrites any previously buffered message. */
+  static void bufferMessage(Context context, byte[] message) {
+    SharedPreferences.Editor editor = getPreferences(context).edit();
+    String encodedMessage =
+        Base64.encodeToString(message, Base64.URL_SAFE | Base64.NO_WRAP  | Base64.NO_PADDING);
+    editor.putString(BUFFERED_MSG_PREF, encodedMessage);
+
+    // This might fail, but at worst we'll just drop a message, which the Ticl must be prepared to
+    // handle.
+    if (!editor.commit()) {
+      logger.warning("Failed writing shared preferences for: bufferMessage");
+    }
+  }
+
+  /**
+   * Removes and returns the buffered Ticl message, if any. If no message was buffered, returns
+   * {@code null}.
+   */
+  static byte[] takeBufferedMessage(Context context) {
+    SharedPreferences preferences = getPreferences(context);
+    String message = preferences.getString(BUFFERED_MSG_PREF, null);
+    if (message == null) {
+      // No message was buffered.
+      return null;
+    }
+    // There is a message to return. Remove the stored value from the preferences.
+    SharedPreferences.Editor editor = preferences.edit();
+    editor.remove(BUFFERED_MSG_PREF);
+
+    // If this fails, we might send the same message twice, which is fine.
+    if (!editor.commit()) {
+      logger.warning("Failed writing shared preferences for: takeBufferedMessage");
+    }
+
+    // Return the decoded message.
+    return Base64.decode(message, Base64.URL_SAFE);
+  }
+
+  /** Returns whether a message has been buffered, for tests. */
+  public static boolean hasBufferedMessageForTest(Context context) {
+    return getPreferences(context).contains(BUFFERED_MSG_PREF);
+  }
+
+  /** Returns a new {@link SharedPreferences} instance to access the channel preferences. */
+  private static SharedPreferences getPreferences(Context context) {
+    return context.getSharedPreferences(PREFERENCES_NAME, Context.MODE_PRIVATE);
+  }
+}