Rewrite SyncStorageEngine to use flat files and in-memory data structures.

The previous implementation used a database for storing all of its state, which could cause
a significant amount of IO activity as its tables were updated through the stages of a sync.
This new implementation replaces that in-memory data structures, with hand-written code
for writing them to persistent storage.

There are now 4 files associated with this class, holding various pieces of its state that
should be consistent.  These are everything from a main XML file of account information that
must always be retained, to a binary file of per-day statistics that can be thrown away at
any time.  Writes of these files as scheduled at various times based on their importance of
the frequency at which they change.

Because the database no longer exists, there needs to be a new explicit interface for
interacting with the sync manager database.  This is provided by new APIs on IContentService,
with a hidden method on ContentResolver to retrieve the IContentService so that various
system entities can use it.  Other changes in other projects are required to update to the
new API.

The goal here is to have as little an impact on the code and functionality outside of
SyncStorageEngine, though due to the necessary change in API it is still somewhat extensive.

1 files changed, 83 insertions, 0 deletions

diff --git a/core/java/android/content/IContentService.aidl b/core/java/android/content/IContentService.aidl
new file mode 100644
index 0000000..8617d949
--- /dev/null
+++ b/core/java/android/content/IContentService.aidl
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * 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 android.content;
+
+import android.content.ActiveSyncInfo;
+import android.content.ISyncStatusObserver;
+import android.content.SyncStatusInfo;
+import android.net.Uri;
+import android.os.Bundle;
+import android.database.IContentObserver;
+
+/**
+ * @hide
+ */
+interface IContentService {
+    void registerContentObserver(in Uri uri, boolean notifyForDescendentsn,
+            IContentObserver observer);
+    void unregisterContentObserver(IContentObserver observer);
+
+    void notifyChange(in Uri uri, IContentObserver observer,
+            boolean observerWantsSelfNotifications, boolean syncToNetwork);
+
+    void startSync(in Uri url, in Bundle extras);
+    void cancelSync(in Uri uri);
+    
+    /**
+     * Check if the provider should be synced when a network tickle is received
+     * @param providerName the provider whose setting we are querying
+     * @return true of the provider should be synced when a network tickle is received
+     */
+    boolean getSyncProviderAutomatically(String providerName);
+
+    /**
+     * Set whether or not the provider is synced when it receives a network tickle.
+     *
+     * @param providerName the provider whose behavior is being controlled
+     * @param sync true if the provider should be synced when tickles are received for it
+     */
+    void setSyncProviderAutomatically(String providerName, boolean sync);
+
+    void setListenForNetworkTickles(boolean flag);
+
+    boolean getListenForNetworkTickles();
+    
+    /**
+     * Returns true if there is currently a sync operation for the given
+     * account or authority in the pending list, or actively being processed.
+     */
+    boolean isSyncActive(String account, String authority);
+    
+    ActiveSyncInfo getActiveSync();
+    
+    /**
+     * Returns the status that matches the authority. If there are multiples accounts for
+     * the authority, the one with the latest "lastSuccessTime" status is returned.
+     * @param authority the authority whose row should be selected
+     * @return the SyncStatusInfo for the authority, or null if none exists
+     */
+    SyncStatusInfo getStatusByAuthority(String authority);
+
+    /**
+     * Return true if the pending status is true of any matching authorities.
+     */
+    boolean isAuthorityPending(String account, String authority);
+    
+    void addStatusChangeListener(int mask, ISyncStatusObserver callback);
+    
+    void removeStatusChangeListener(ISyncStatusObserver callback);
+}