/*
* Copyright (C) 2008 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 com.android.email.provider;
import com.android.emailcommon.Logging;
import com.android.emailcommon.internet.MimeUtility;
import com.android.emailcommon.provider.EmailContent;
import com.android.emailcommon.provider.EmailContent.Attachment;
import com.android.emailcommon.provider.EmailContent.AttachmentColumns;
import com.android.emailcommon.utility.AttachmentUtilities;
import com.android.emailcommon.utility.AttachmentUtilities.Columns;
import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.content.pm.PackageManager;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Binder;
import android.os.ParcelFileDescriptor;
import android.util.Log;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
/*
* A simple ContentProvider that allows file access to Email's attachments.
*
* The URI scheme is as follows. For raw file access:
* content://com.android.email.attachmentprovider/acct#/attach#/RAW
*
* And for access to thumbnails:
* content://com.android.email.attachmentprovider/acct#/attach#/THUMBNAIL/width#/height#
*
* The on-disk (storage) schema is as follows.
*
* Attachments are stored at: <database-path>/account#.db_att/item#
* Thumbnails are stored at: <cache-path>/thmb_account#_item#
*
* Using the standard application context, account #10 and attachment # 20, this would be:
* /data/data/com.android.email/databases/10.db_att/20
* /data/data/com.android.email/cache/thmb_10_20
*/
public class AttachmentProvider extends ContentProvider {
private static final String[] MIME_TYPE_PROJECTION = new String[] {
AttachmentColumns.MIME_TYPE, AttachmentColumns.FILENAME };
private static final int MIME_TYPE_COLUMN_MIME_TYPE = 0;
private static final int MIME_TYPE_COLUMN_FILENAME = 1;
private static final String[] PROJECTION_QUERY = new String[] { AttachmentColumns.FILENAME,
AttachmentColumns.SIZE, AttachmentColumns.CONTENT_URI };
@Override
public boolean onCreate() {
/*
* We use the cache dir as a temporary directory (since Android doesn't give us one) so
* on startup we'll clean up any .tmp files from the last run.
*/
File[] files = getContext().getCacheDir().listFiles();
for (File file : files) {
String filename = file.getName();
if (filename.endsWith(".tmp") || filename.startsWith("thmb_")) {
file.delete();
}
}
return true;
}
/**
* Returns the mime type for a given attachment. There are three possible results:
* - If thumbnail Uri, always returns "image/png" (even if there's no attachment)
* - If the attachment does not exist, returns null
* - Returns the mime type of the attachment
*/
@Override
public String getType(Uri uri) {
long callingId = Binder.clearCallingIdentity();
try {
List<String> segments = uri.getPathSegments();
String id = segments.get(1);
String format = segments.get(2);
if (AttachmentUtilities.FORMAT_THUMBNAIL.equals(format)) {
return "image/png";
} else {
uri = ContentUris.withAppendedId(Attachment.CONTENT_URI, Long.parseLong(id));
Cursor c = getContext().getContentResolver().query(uri, MIME_TYPE_PROJECTION, null,
null, null);
try {
if (c.moveToFirst()) {
String mimeType = c.getString(MIME_TYPE_COLUMN_MIME_TYPE);
String fileName = c.getString(MIME_TYPE_COLUMN_FILENAME);
mimeType = AttachmentUtilities.inferMimeType(fileName, mimeType);
return mimeType;
}
} finally {
c.close();
}
return null;
}
} finally {
Binder.restoreCallingIdentity(callingId);
}
}
/**
* Open an attachment file. There are two "formats" - "raw", which returns an actual file,
* and "thumbnail", which attempts to generate a thumbnail image.
*
* Thumbnails are cached for easy space recovery and cleanup.
*
* TODO: The thumbnail format returns null for its failure cases, instead of throwing
* FileNotFoundException, and should be fixed for consistency.
*
* @throws FileNotFoundException
*/
@Override
public ParcelFileDescriptor openFile(Uri uri, String mode) throws FileNotFoundException {
// If this is a write, the caller must have the EmailProvider permission, which is
// based on signature only
if (mode.equals("w")) {
Context context = getContext();
if (context.checkCallingPermission(EmailContent.PROVIDER_PERMISSION)
!= PackageManager.PERMISSION_GRANTED) {
throw new FileNotFoundException();
}
List<String> segments = uri.getPathSegments();
String accountId = segments.get(0);
String id = segments.get(1);
File saveIn =
AttachmentUtilities.getAttachmentDirectory(context, Long.parseLong(accountId));
if (!saveIn.exists()) {
saveIn.mkdirs();
}
File newFile = new File(saveIn, id);
return ParcelFileDescriptor.open(
newFile, ParcelFileDescriptor.MODE_READ_WRITE |
ParcelFileDescriptor.MODE_CREATE | ParcelFileDescriptor.MODE_TRUNCATE);
}
long callingId = Binder.clearCallingIdentity();
try {
List<String> segments = uri.getPathSegments();
String accountId = segments.get(0);
String id = segments.get(1);
String format = segments.get(2);
if (AttachmentUtilities.FORMAT_THUMBNAIL.equals(format)) {
int width = Integer.parseInt(segments.get(3));
int height = Integer.parseInt(segments.get(4));
String filename = "thmb_" + accountId + "_" + id;
File dir = getContext().getCacheDir();
File file = new File(dir, filename);
if (!file.exists()) {
Uri attachmentUri = AttachmentUtilities.
getAttachmentUri(Long.parseLong(accountId), Long.parseLong(id));
Cursor c = query(attachmentUri,
new String[] { Columns.DATA }, null, null, null);
if (c != null) {
try {
if (c.moveToFirst()) {
attachmentUri = Uri.parse(c.getString(0));
} else {
return null;
}
} finally {
c.close();
}
}
String type = getContext().getContentResolver().getType(attachmentUri);
try {
InputStream in =
getContext().getContentResolver().openInputStream(attachmentUri);
Bitmap thumbnail = createThumbnail(type, in);
if (thumbnail == null) {
return null;
}
thumbnail = Bitmap.createScaledBitmap(thumbnail, width, height, true);
FileOutputStream out = new FileOutputStream(file);
thumbnail.compress(Bitmap.CompressFormat.PNG, 100, out);
out.close();
in.close();
} catch (IOException ioe) {
Log.d(Logging.LOG_TAG, "openFile/thumbnail failed with " +
ioe.getMessage());
return null;
} catch (OutOfMemoryError oome) {
Log.d(Logging.LOG_TAG, "openFile/thumbnail failed with " +
oome.getMessage());
return null;
}
}
return ParcelFileDescriptor.open(file, ParcelFileDescriptor.MODE_READ_ONLY);
}
else {
return ParcelFileDescriptor.open(
new File(getContext().getDatabasePath(accountId + ".db_att"), id),
ParcelFileDescriptor.MODE_READ_ONLY);
}
} finally {
Binder.restoreCallingIdentity(callingId);
}
}
@Override
public int delete(Uri uri, String arg1, String[] arg2) {
return 0;
}
@Override
public Uri insert(Uri uri, ContentValues values) {
return null;
}
/**
* Returns a cursor based on the data in the attachments table, or null if the attachment
* is not recorded in the table.
*
* Supports REST Uri only, for a single row - selection, selection args, and sortOrder are
* ignored (non-null values should probably throw an exception....)
*/
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs,
String sortOrder) {
long callingId = Binder.clearCallingIdentity();
try {
if (projection == null) {
projection =
new String[] {
Columns._ID,
Columns.DATA,
};
}
List<String> segments = uri.getPathSegments();
String accountId = segments.get(0);
String id = segments.get(1);
String format = segments.get(2);
String name = null;
int size = -1;
String contentUri = null;
uri = ContentUris.withAppendedId(Attachment.CONTENT_URI, Long.parseLong(id));
Cursor c = getContext().getContentResolver().query(uri, PROJECTION_QUERY,
null, null, null);
try {
if (c.moveToFirst()) {
name = c.getString(0);
size = c.getInt(1);
contentUri = c.getString(2);
} else {
return null;
}
} finally {
c.close();
}
MatrixCursor ret = new MatrixCursor(projection);
Object[] values = new Object[projection.length];
for (int i = 0, count = projection.length; i < count; i++) {
String column = projection[i];
if (Columns._ID.equals(column)) {
values[i] = id;
}
else if (Columns.DATA.equals(column)) {
values[i] = contentUri;
}
else if (Columns.DISPLAY_NAME.equals(column)) {
values[i] = name;
}
else if (Columns.SIZE.equals(column)) {
values[i] = size;
}
}
ret.addRow(values);
return ret;
} finally {
Binder.restoreCallingIdentity(callingId);
}
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
return 0;
}
private Bitmap createThumbnail(String type, InputStream data) {
if(MimeUtility.mimeTypeMatches(type, "image/*")) {
return createImageThumbnail(data);
}
return null;
}
private Bitmap createImageThumbnail(InputStream data) {
try {
Bitmap bitmap = BitmapFactory.decodeStream(data);
return bitmap;
} catch (OutOfMemoryError oome) {
Log.d(Logging.LOG_TAG, "createImageThumbnail failed with " + oome.getMessage());
return null;
} catch (Exception e) {
Log.d(Logging.LOG_TAG, "createImageThumbnail failed with " + e.getMessage());
return null;
}
}
/**
* Need this to suppress warning in unit tests.
*/
@Override
public void shutdown() {
// Don't call super.shutdown(), which emits a warning...
}
}