1 files changed, 451 insertions, 0 deletions
diff --git a/packages/CMSettingsProvider/src/org/cyanogenmod/cmsettings/CMSettingsProvider.java b/packages/CMSettingsProvider/src/org/cyanogenmod/cmsettings/CMSettingsProvider.java
new file mode 100644
index 0000000..eeabba3
--- /dev/null
+++ b/packages/CMSettingsProvider/src/org/cyanogenmod/cmsettings/CMSettingsProvider.java
@@ -0,0 +1,451 @@
+/**
+ * Copyright (c) 2015, The CyanogenMod 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 org.cyanogenmod.cmsettings;
+
+import android.content.ContentProvider;
+import android.content.ContentResolver;
+import android.content.ContentUris;
+import android.content.ContentValues;
+import android.content.UriMatcher;
+import android.content.pm.PackageManager;
+import android.database.AbstractCursor;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteCantOpenDatabaseException;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteQueryBuilder;
+import android.net.Uri;
+import android.os.Binder;
+import android.os.SystemProperties;
+import android.os.UserHandle;
+import android.os.UserManager;
+import android.text.TextUtils;
+import android.util.Log;
+import android.util.SparseArray;
+import cyanogenmod.providers.CMSettings;
+
+/**
+ * The CMSettingsProvider serves as a {@link ContentProvider} for CM specific settings
+ */
+public class CMSettingsProvider extends ContentProvider {
+    private static final String TAG = "CMSettingsProvider";
+    private static final boolean LOCAL_LOGV = false;
+
+    private static final boolean USER_CHECK_THROWS = true;
+
+    // Each defined user has their own settings
+    protected final SparseArray<CMDatabaseHelper> mDbHelpers = new SparseArray<CMDatabaseHelper>();
+
+    private static final int SYSTEM = 1;
+    private static final int SECURE = 2;
+    private static final int GLOBAL = 3;
+
+    private static final UriMatcher sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
+
+    static {
+        sUriMatcher.addURI(CMSettings.AUTHORITY, CMDatabaseHelper.CMTableNames.TABLE_SYSTEM,
+                SYSTEM);
+        sUriMatcher.addURI(CMSettings.AUTHORITY, CMDatabaseHelper.CMTableNames.TABLE_SECURE,
+                SECURE);
+        sUriMatcher.addURI(CMSettings.AUTHORITY, CMDatabaseHelper.CMTableNames.TABLE_GLOBAL,
+                GLOBAL);
+        // TODO add other paths for getting specific items
+    }
+
+    private UserManager mUserManager;
+    private Uri.Builder mUriBuilder;
+
+    @Override
+    public boolean onCreate() {
+        if (LOCAL_LOGV) Log.d(TAG, "Creating CMSettingsProvider");
+
+        mUserManager = UserManager.get(getContext());
+
+        establishDbTracking(UserHandle.USER_OWNER);
+
+        mUriBuilder = new Uri.Builder();
+        mUriBuilder.scheme(ContentResolver.SCHEME_CONTENT);
+        mUriBuilder.authority(CMSettings.AUTHORITY);
+
+        // TODO Add migration for cm settings
+
+        return true;
+    }
+
+    @Override
+    public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
+            String sortOrder) {
+        if (uri == null) {
+            throw new IllegalArgumentException("Uri cannot be null");
+        }
+
+        String tableName = getTableNameFromUri(uri);
+        checkWritePermissions(tableName);
+
+        int callingUserId = UserHandle.getCallingUserId();
+        CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName,
+                callingUserId));
+        SQLiteDatabase db = dbHelper.getReadableDatabase();
+
+        SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
+        queryBuilder.setTables(tableName);
+
+        Cursor returnCursor = queryBuilder.query(db, projection, selection, selectionArgs, null,
+                null, sortOrder);
+        // the default Cursor interface does not support per-user observation
+        try {
+            AbstractCursor abstractCursor = (AbstractCursor) returnCursor;
+            abstractCursor.setNotificationUri(getContext().getContentResolver(), uri,
+                    callingUserId);
+        } catch (ClassCastException e) {
+            // details of the concrete Cursor implementation have changed and this code has
+            // not been updated to match -- complain and fail hard.
+            Log.wtf(TAG, "Incompatible cursor derivation");
+            throw e;
+        }
+
+        return returnCursor;
+    }
+
+    @Override
+    public String getType(Uri uri) {
+        // TODO: Implement
+        return null;
+    }
+
+    @Override
+    public int bulkInsert(Uri uri, ContentValues[] values) {
+        return bulkInsertForUser(UserHandle.getCallingUserId(), uri, values);
+    }
+
+    /**
+     * Performs a bulk insert for a specific user.
+     * @param userId The user id to perform the bulk insert for.
+     * @param uri The content:// URI of the insertion request.
+     * @param values An array of sets of column_name/value pairs to add to the database.
+     *    This must not be {@code null}.
+     * @return Number of rows inserted.
+     */
+    int bulkInsertForUser(int userId, Uri uri, ContentValues[] values) {
+        if (uri == null) {
+            throw new IllegalArgumentException("Uri cannot be null");
+        }
+
+        if (values == null) {
+            throw new IllegalArgumentException("ContentValues cannot be null");
+        }
+
+        int numRowsAffected = 0;
+
+        String tableName = getTableNameFromUri(uri);
+        checkWritePermissions(tableName);
+
+        CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName, userId));
+        SQLiteDatabase db = dbHelper.getWritableDatabase();
+
+        db.beginTransaction();
+        try {
+            for (ContentValues value : values) {
+                if (value == null) {
+                    continue;
+                }
+
+                long rowId = db.insert(tableName, null, value);
+
+                if (rowId >= 0) {
+                    numRowsAffected++;
+
+                    if (LOCAL_LOGV) Log.d(TAG, tableName + " <- " + values);
+                } else {
+                    return 0;
+                }
+            }
+
+            db.setTransactionSuccessful();
+        } finally {
+            db.endTransaction();
+            db.close();
+        }
+
+        if (numRowsAffected > 0) {
+            getContext().getContentResolver().notifyChange(uri, null);
+            notifyChange(uri, tableName, userId);
+            if (LOCAL_LOGV) Log.d(TAG, tableName + ": " + numRowsAffected + " row(s) inserted");
+        }
+
+        return numRowsAffected;
+    }
+
+    @Override
+    public Uri insert(Uri uri, ContentValues values) {
+        if (uri == null) {
+            throw new IllegalArgumentException("Uri cannot be null");
+        }
+
+        if (values == null) {
+            throw new IllegalArgumentException("ContentValues cannot be null");
+        }
+
+        String tableName = getTableNameFromUri(uri);
+        checkWritePermissions(tableName);
+
+        int callingUserId = UserHandle.getCallingUserId();
+        CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName,
+                callingUserId));
+
+        long rowId = -1;
+
+        SQLiteDatabase db = dbHelper.getWritableDatabase();
+        try {
+            rowId = db.insert(tableName, null, values);
+        } finally {
+            db.close();
+        }
+
+        Uri returnUri = null;
+        if (rowId != -1) {
+            returnUri = ContentUris.withAppendedId(uri, rowId);
+            notifyChange(returnUri, tableName, callingUserId);
+            if (LOCAL_LOGV) Log.d(TAG, "Inserted row id: " + rowId + " into tableName: " +
+                    tableName);
+        }
+
+        return returnUri;
+    }
+
+    @Override
+    public int delete(Uri uri, String selection, String[] selectionArgs) {
+        if (uri == null) {
+            throw new IllegalArgumentException("Uri cannot be null");
+        }
+
+        int numRowsAffected = 0;
+
+        // Allow only selection by key; a null/empty selection string will cause all rows in the
+        // table to be deleted
+        if (!TextUtils.isEmpty(selection) && selectionArgs.length > 0) {
+            String tableName = getTableNameFromUri(uri);
+            checkWritePermissions(tableName);
+
+            int callingUserId = UserHandle.getCallingUserId();
+            CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName,
+                    callingUserId));
+            SQLiteDatabase db = dbHelper.getWritableDatabase();
+
+            try {
+                numRowsAffected = db.delete(tableName, selection, selectionArgs);
+            } finally {
+                db.close();
+            }
+
+            if (numRowsAffected > 0) {
+                notifyChange(uri, tableName, callingUserId);
+                if (LOCAL_LOGV) Log.d(TAG, tableName + ": " + numRowsAffected + " row(s) deleted");
+            }
+        }
+
+        return numRowsAffected;
+    }
+
+    @Override
+    public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
+        if (uri == null) {
+            throw new IllegalArgumentException("Uri cannot be null");
+        }
+
+        if (values == null) {
+            throw new IllegalArgumentException("ContentValues cannot be null");
+        }
+
+        String tableName = getTableNameFromUri(uri);
+        checkWritePermissions(tableName);
+
+        int callingUserId = UserHandle.getCallingUserId();
+        CMDatabaseHelper dbHelper = getOrEstablishDatabase(getUserIdForTable(tableName,
+                callingUserId));
+
+        int numRowsAffected = 0;
+
+        SQLiteDatabase db = dbHelper.getWritableDatabase();
+        try {
+            numRowsAffected = db.update(tableName, values, selection, selectionArgs);
+        } finally {
+            db.close();
+        }
+
+        if (numRowsAffected > 0) {
+            getContext().getContentResolver().notifyChange(uri, null);
+            if (LOCAL_LOGV) Log.d(TAG, tableName + ": " + numRowsAffected + " row(s) updated");
+        }
+
+        return numRowsAffected;
+    }
+
+    /**
+     * Tries to get a {@link CMDatabaseHelper} for the specified user and if it does not exist, a
+     * new instance of {@link CMDatabaseHelper} is created for the specified user and returned.
+     * @param callingUser
+     * @return
+     */
+    private CMDatabaseHelper getOrEstablishDatabase(int callingUser) {
+        if (callingUser >= android.os.Process.SYSTEM_UID) {
+            if (USER_CHECK_THROWS) {
+                throw new IllegalArgumentException("Uid rather than user handle: " + callingUser);
+            } else {
+                Log.wtf(TAG, "Establish db for uid rather than user: " + callingUser);
+            }
+        }
+
+        long oldId = Binder.clearCallingIdentity();
+        try {
+            CMDatabaseHelper dbHelper;
+            synchronized (this) {
+                dbHelper = mDbHelpers.get(callingUser);
+            }
+            if (null == dbHelper) {
+                establishDbTracking(callingUser);
+                synchronized (this) {
+                    dbHelper = mDbHelpers.get(callingUser);
+                }
+            }
+            return dbHelper;
+        } finally {
+            Binder.restoreCallingIdentity(oldId);
+        }
+    }
+
+    /**
+     * Check if a {@link CMDatabaseHelper} exists for a user and if it doesn't, a new helper is
+     * created and added to the list of tracked database helpers
+     * @param userId
+     */
+    private void establishDbTracking(int userId) {
+        CMDatabaseHelper dbHelper;
+
+        synchronized (this) {
+            dbHelper = mDbHelpers.get(userId);
+            if (LOCAL_LOGV) {
+                Log.i(TAG, "Checking cm settings db helper for user " + userId);
+            }
+            if (dbHelper == null) {
+                if (LOCAL_LOGV) {
+                    Log.i(TAG, "Installing new cm settings db helper for user " + userId);
+                }
+                dbHelper = new CMDatabaseHelper(getContext(), userId);
+                mDbHelpers.append(userId, dbHelper);
+            }
+        }
+
+        // Initialization of the db *outside* the locks.  It's possible that racing
+        // threads might wind up here, the second having read the cache entries
+        // written by the first, but that's benign: the SQLite helper implementation
+        // manages concurrency itself, and it's important that we not run the db
+        // initialization with any of our own locks held, so we're fine.
+        SQLiteDatabase db = null;
+        try {
+            db = dbHelper.getWritableDatabase();
+        } catch (SQLiteCantOpenDatabaseException ex){
+            Log.e(TAG, "Unable to open writable database for user: " + userId, ex);
+        } finally {
+            db.close();
+        }
+    }
+
+    /**
+     * Makes sure the caller has permission to write this data.
+     * @param tableName supplied by the caller
+     * @throws SecurityException if the caller is forbidden to write.
+     */
+    private void checkWritePermissions(String tableName) {
+        if ((CMDatabaseHelper.CMTableNames.TABLE_SECURE.equals(tableName) ||
+                CMDatabaseHelper.CMTableNames.TABLE_GLOBAL.equals(tableName)) &&
+                getContext().checkCallingOrSelfPermission(
+                        cyanogenmod.platform.Manifest.permission.WRITE_SECURE_SETTINGS) !=
+                        PackageManager.PERMISSION_GRANTED) {
+            throw new SecurityException(
+                    String.format("Permission denial: writing to cm secure settings requires %1$s",
+                            cyanogenmod.platform.Manifest.permission.WRITE_SECURE_SETTINGS));
+        }
+    }
+
+    /**
+     * Utilizes an {@link UriMatcher} to check for a valid combination of scheme, authority, and
+     * path and returns the corresponding table name
+     * @param uri
+     * @return Table name
+     */
+    private String getTableNameFromUri(Uri uri) {
+        int code = sUriMatcher.match(uri);
+
+        switch (code) {
+            case SYSTEM:
+                return CMDatabaseHelper.CMTableNames.TABLE_SYSTEM;
+            case SECURE:
+                return CMDatabaseHelper.CMTableNames.TABLE_SECURE;
+            case GLOBAL:
+                return CMDatabaseHelper.CMTableNames.TABLE_GLOBAL;
+            default:
+                throw new IllegalArgumentException("Invalid uri: " + uri);
+        }
+    }
+
+    /**
+     * If the table is Global, the owner's user id is returned. Otherwise, the original user id
+     * is returned.
+     * @param tableName
+     * @param userId
+     * @return User id
+     */
+    private int getUserIdForTable(String tableName, int userId) {
+        return CMDatabaseHelper.CMTableNames.TABLE_GLOBAL.equals(tableName) ?
+                UserHandle.USER_OWNER : userId;
+    }
+
+    /**
+     * Modify setting version for an updated table before notifying of change. The
+     * {@link CMSettings} class uses these to provide client-side caches.
+     * @param uri to send notifications for
+     * @param userId
+     */
+    private void notifyChange(Uri uri, String tableName, int userId) {
+        String property = null;
+        final boolean isGlobal = tableName.equals(CMDatabaseHelper.CMTableNames.TABLE_GLOBAL);
+        if (tableName.equals(CMDatabaseHelper.CMTableNames.TABLE_SYSTEM)) {
+            property = CMSettings.System.SYS_PROP_CM_SETTING_VERSION;
+        } else if (tableName.equals(CMDatabaseHelper.CMTableNames.TABLE_SECURE)) {
+            property = CMSettings.Secure.SYS_PROP_CM_SETTING_VERSION;
+        } else if (isGlobal) {
+            property = CMSettings.Global.SYS_PROP_CM_SETTING_VERSION;
+        }
+
+        if (property != null) {
+            long version = SystemProperties.getLong(property, 0) + 1;
+            if (LOCAL_LOGV) Log.v(TAG, "property: " + property + "=" + version);
+            SystemProperties.set(property, Long.toString(version));
+        }
+
+        final int notifyTarget = isGlobal ? UserHandle.USER_ALL : userId;
+        final long oldId = Binder.clearCallingIdentity();
+        try {
+            getContext().getContentResolver().notifyChange(uri, null, true, notifyTarget);
+        } finally {
+            Binder.restoreCallingIdentity(oldId);
+        }
+        if (LOCAL_LOGV) Log.v(TAG, "notifying for " + notifyTarget + ": " + uri);
+    }
+
+    // TODO Add caching
+}