1/*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.exchange;
18
19import android.content.ContentResolver;
20import android.content.ContentUris;
21import android.content.ContentValues;
22import android.content.Context;
23import android.database.Cursor;
24import android.net.TrafficStats;
25import android.os.SystemClock;
26import android.provider.CalendarContract;
27import android.provider.ContactsContract;
28import android.text.TextUtils;
29import android.text.format.DateUtils;
30
31import com.android.emailcommon.TrafficFlags;
32import com.android.emailcommon.mail.MessagingException;
33import com.android.emailcommon.provider.Account;
34import com.android.emailcommon.provider.EmailContent;
35import com.android.emailcommon.provider.EmailContent.AccountColumns;
36import com.android.emailcommon.provider.EmailContent.HostAuthColumns;
37import com.android.emailcommon.provider.EmailContent.MailboxColumns;
38import com.android.emailcommon.provider.HostAuth;
39import com.android.emailcommon.provider.Mailbox;
40import com.android.emailcommon.provider.MailboxUtilities;
41import com.android.emailcommon.provider.Policy;
42import com.android.emailcommon.provider.ProviderUnavailableException;
43import com.android.emailcommon.service.PolicyServiceProxy;
44import com.android.exchange.CommandStatusException.CommandStatus;
45import com.android.exchange.adapter.AccountSyncAdapter;
46import com.android.exchange.adapter.FolderSyncParser;
47import com.android.exchange.adapter.Parser.EasParserException;
48import com.android.exchange.adapter.PingParser;
49import com.android.exchange.adapter.Serializer;
50import com.android.exchange.adapter.Tags;
51import com.android.mail.utils.LogUtils;
52import com.google.common.annotations.VisibleForTesting;
53
54import org.apache.http.Header;
55import org.apache.http.HttpStatus;
56import org.apache.http.entity.ByteArrayEntity;
57
58import java.io.IOException;
59import java.io.InputStream;
60import java.util.ArrayList;
61import java.util.HashMap;
62
63/**
64 * AccountMailbox handles sync for the EAS "account mailbox"; this includes sync of the mailbox list
65 * as well as management of mailbox push (using the EAS "Ping" command
66 */
67public class EasAccountService extends EasSyncService {
68    private static final String WHERE_ACCOUNT_AND_SYNC_INTERVAL_PING =
69        MailboxColumns.ACCOUNT_KEY + "=? and " + MailboxColumns.SYNC_INTERVAL +
70        '=' + Mailbox.CHECK_INTERVAL_PING;
71    private static final String AND_FREQUENCY_PING_PUSH_AND_NOT_ACCOUNT_MAILBOX = " AND " +
72        MailboxColumns.SYNC_INTERVAL + " IN (" + Mailbox.CHECK_INTERVAL_PING +
73        ',' + Mailbox.CHECK_INTERVAL_PUSH + ") AND " + MailboxColumns.TYPE + "!=\"" +
74        Mailbox.TYPE_EAS_ACCOUNT_MAILBOX + '\"';
75    private static final String WHERE_PUSH_HOLD_NOT_ACCOUNT_MAILBOX =
76        MailboxColumns.ACCOUNT_KEY + "=? and " + MailboxColumns.SYNC_INTERVAL +
77        '=' + Mailbox.CHECK_INTERVAL_PUSH_HOLD;
78    private static final String WHERE_ACCOUNT_KEY_AND_SERVER_ID =
79        MailboxColumns.ACCOUNT_KEY + "=? and " + MailboxColumns.SERVER_ID + "=?";
80    protected static final String WHERE_IN_ACCOUNT_AND_PUSHABLE =
81            MailboxColumns.ACCOUNT_KEY + "=? and type in (" + Mailbox.TYPE_INBOX + ','
82            + Mailbox.TYPE_EAS_ACCOUNT_MAILBOX + ',' + Mailbox.TYPE_CONTACTS + ','
83            + Mailbox.TYPE_CALENDAR + ')';
84
85    /**
86     * We start with an 8 minute timeout, and increase/decrease by 3 minutes at a time.  There's
87     * no point having a timeout shorter than 5 minutes, I think; at that point, we can just let
88     * the ping exception out.  The maximum I use is 17 minutes, which is really an empirical
89     * choice; too long and we risk silent connection loss and loss of push for that period.  Too
90     * short and we lose efficiency/battery life.
91     *
92     * If we ever have to drop the ping timeout, we'll never increase it again.  There's no point
93     * going into hysteresis; the NAT timeout isn't going to change without a change in connection,
94     * which will cause the sync service to be restarted at the starting heartbeat and going through
95     * the process again.
96     */
97    static private final int PING_MINUTES = 60; // in seconds
98    static private final int PING_FUDGE_LOW = 10;
99    static private final int PING_STARTING_HEARTBEAT = (8*PING_MINUTES)-PING_FUDGE_LOW;
100    static private final int PING_HEARTBEAT_INCREMENT = 3*PING_MINUTES;
101
102    static private final int PROTOCOL_PING_STATUS_COMPLETED = 1;
103    static private final int PROTOCOL_PING_STATUS_BAD_PARAMETERS = 3;
104    static private final int PROTOCOL_PING_STATUS_RETRY = 8;
105
106    // Fallbacks (in minutes) for ping loop failures
107    static private final int MAX_PING_FAILURES = 1;
108    static private final int PING_FALLBACK_INBOX = 5;
109    static private final int PING_FALLBACK_PIM = 25;
110
111    // The amount of time the account mailbox will sleep if there are no pingable mailboxes
112    // This could happen if the sync time is set to "never"; we always want to check in from time
113    // to time, however, for folder list/policy changes
114    static private final int ACCOUNT_MAILBOX_SLEEP_TIME = (int)(20 * DateUtils.MINUTE_IN_MILLIS);
115    static private final String ACCOUNT_MAILBOX_SLEEP_TEXT = "Account mailbox sleeping for " +
116            (ACCOUNT_MAILBOX_SLEEP_TIME / DateUtils.MINUTE_IN_MILLIS) + "m";
117
118    // Our heartbeat when we are waiting for ping boxes to be ready
119    /*package*/ int mPingForceHeartbeat = 2*PING_MINUTES;
120    // The minimum heartbeat we will send
121    /*package*/ int mPingMinHeartbeat = (5*PING_MINUTES)-PING_FUDGE_LOW;
122    // The maximum heartbeat we will send
123    /*package*/ int mPingMaxHeartbeat = (17*PING_MINUTES)-PING_FUDGE_LOW;
124    // The ping time (in seconds)
125    /*package*/ int mPingHeartbeat = PING_STARTING_HEARTBEAT;
126    // The longest successful ping heartbeat
127    private int mPingHighWaterMark = 0;
128    // Whether we've ever lowered the heartbeat
129    /*package*/ boolean mPingHeartbeatDropped = false;
130
131    private final String[] mBindArguments = new String[2];
132    private ArrayList<String> mPingChangeList;
133
134    protected EasAccountService(Context _context, Mailbox _mailbox) {
135        super(_context, _mailbox);
136    }
137
138    @VisibleForTesting
139    protected EasAccountService() {
140    }
141
142    @Override
143    public void run() {
144        mExitStatus = EXIT_DONE;
145        try {
146            // Make sure account and mailbox are still valid
147            if (!setupService()) return;
148            // If we've been stopped, we're done
149            if (mStop) return;
150
151            try {
152                mDeviceId = ExchangeService.getDeviceId(mContext);
153                int trafficFlags = TrafficFlags.getSyncFlags(mContext, mAccount);
154                TrafficStats.setThreadStatsTag(trafficFlags | TrafficFlags.DATA_EMAIL);
155                if ((mMailbox == null) || (mAccount == null)) {
156                    return;
157                } else {
158                    sync();
159                }
160            } catch (EasAuthenticationException e) {
161                userLog("Caught authentication error");
162                mExitStatus = EXIT_LOGIN_FAILURE;
163            } catch (IOException e) {
164                String message = e.getMessage();
165                userLog("Caught IOException: ", (message == null) ? "No message" : message);
166                mExitStatus = EXIT_IO_ERROR;
167            } catch (Exception e) {
168                userLog("Uncaught exception in AccountMailboxService", e);
169            } finally {
170                ExchangeService.done(this);
171                if (!mStop) {
172                    userLog("Sync finished");
173                    switch (mExitStatus) {
174                        case EXIT_SECURITY_FAILURE:
175                            // Ask for a new folder list. This should wake up the account mailbox; a
176                            // security error in account mailbox should start provisioning
177                            ExchangeService.reloadFolderList(mContext, mAccount.mId, true);
178                            break;
179                        case EXIT_EXCEPTION:
180                            errorLog("Sync ended due to an exception.");
181                            break;
182                    }
183                } else {
184                    userLog("Stopped sync finished.");
185                }
186
187                // Make sure ExchangeService knows about this
188                ExchangeService.kick("sync finished");
189            }
190        } catch (ProviderUnavailableException e) {
191            LogUtils.e(TAG, "EmailProvider unavailable; sync ended prematurely");
192        }
193    }
194
195    /**
196     * If possible, update the account to the new server address; report result
197     * @param resp the EasResponse from the current POST
198     * @return whether or not the redirect is handled and the POST should be retried
199     */
200    private boolean canHandleAccountMailboxRedirect(EasResponse resp) {
201        userLog("AccountMailbox redirect error");
202        HostAuth ha =
203                HostAuth.restoreHostAuthWithId(mContext, mAccount.mHostAuthKeyRecv);
204        if (ha != null && getValidateRedirect(resp, ha)) {
205            // Update the account's HostAuth with new values
206            ContentValues haValues = new ContentValues();
207            haValues.put(HostAuthColumns.ADDRESS, ha.mAddress);
208            ha.update(mContext, haValues);
209            return true;
210        }
211        return false;
212    }
213
214    /**
215     * Performs FolderSync
216     *
217     * @throws IOException
218     * @throws EasParserException
219     */
220    public void sync() throws IOException, EasParserException {
221         // Check that the account's mailboxes are consistent
222        MailboxUtilities.checkMailboxConsistency(mContext, mAccount.mId);
223        // Initialize exit status to success
224        try {
225            if (mAccount.mSyncKey == null) {
226                mAccount.mSyncKey = "0";
227                userLog("Account syncKey INIT to 0");
228                ContentValues cv = new ContentValues();
229                cv.put(AccountColumns.SYNC_KEY, mAccount.mSyncKey);
230                mAccount.update(mContext, cv);
231            }
232
233            boolean firstSync = mAccount.mSyncKey.equals("0");
234            if (firstSync) {
235                userLog("Initial FolderSync");
236            }
237
238            // When we first start up, change all mailboxes to push.
239            ContentValues cv = new ContentValues();
240            cv.put(Mailbox.SYNC_INTERVAL, Mailbox.CHECK_INTERVAL_PUSH);
241            if (mContentResolver.update(Mailbox.CONTENT_URI, cv,
242                    WHERE_ACCOUNT_AND_SYNC_INTERVAL_PING,
243                    new String[] {Long.toString(mAccount.mId)}) > 0) {
244                ExchangeService.kick("change ping boxes to push");
245            }
246
247            // Determine our protocol version, if we haven't already and save it in the Account
248            // Also re-check protocol version at least once a day (in case of upgrade)
249            if (mAccount.mProtocolVersion == null || firstSync ||
250                   ((System.currentTimeMillis() - mMailbox.mSyncTime) > DateUtils.DAY_IN_MILLIS)) {
251                userLog("Determine EAS protocol version");
252                EasResponse resp = sendHttpClientOptions();
253                try {
254                    int code = resp.getStatus();
255                    userLog("OPTIONS response: ", code);
256                    if (code == HttpStatus.SC_OK) {
257                        Header header = resp.getHeader("MS-ASProtocolCommands");
258                        userLog(header.getValue());
259                        header = resp.getHeader("ms-asprotocolversions");
260                        try {
261                            setupProtocolVersion(this, header);
262                        } catch (MessagingException e) {
263                            // Since we've already validated, this can't really happen
264                            // But if it does, we'll rethrow this...
265                            throw new IOException(e);
266                        }
267                        // Save the protocol version
268                        cv.clear();
269                        // Save the protocol version in the account; if we're using 12.0 or greater,
270                        // set the flag for support of SmartForward
271                        cv.put(Account.PROTOCOL_VERSION, mProtocolVersion);
272                        if (mProtocolVersionDouble >= 12.0) {
273                            cv.put(Account.FLAGS,
274                                    mAccount.mFlags |
275                                    Account.FLAGS_SUPPORTS_SMART_FORWARD |
276                                    Account.FLAGS_SUPPORTS_SEARCH |
277                                    Account.FLAGS_SUPPORTS_GLOBAL_SEARCH);
278                        }
279                        mAccount.update(mContext, cv);
280                        cv.clear();
281                        // Save the sync time of the account mailbox to current time
282                        cv.put(Mailbox.SYNC_TIME, System.currentTimeMillis());
283                        mMailbox.update(mContext, cv);
284                     } else if (code == EAS_REDIRECT_CODE && canHandleAccountMailboxRedirect(resp)) {
285                        // Cause this to re-run
286                        throw new IOException("Will retry after a brief hold...");
287                     } else if (resp.isProvisionError()) {
288                         throw new CommandStatusException(CommandStatus.NEEDS_PROVISIONING);
289                     } else if (resp.isAuthError()) {
290                         mExitStatus = EasSyncService.EXIT_LOGIN_FAILURE;
291                         return;
292                     } else {
293                        errorLog("OPTIONS command failed; throwing IOException");
294                        throw new IOException();
295                    }
296                } finally {
297                    resp.close();
298                }
299            }
300
301            // Change all pushable boxes to push when we start the account mailbox
302            if (mAccount.mSyncInterval == Account.CHECK_INTERVAL_PUSH) {
303                cv.clear();
304                cv.put(Mailbox.SYNC_INTERVAL, Mailbox.CHECK_INTERVAL_PUSH);
305                if (mContentResolver.update(Mailbox.CONTENT_URI, cv,
306                        WHERE_IN_ACCOUNT_AND_PUSHABLE,
307                        new String[] {Long.toString(mAccount.mId)}) > 0) {
308                    userLog("Push account; set pushable boxes to push...");
309                }
310            }
311
312            while (!isStopped()) {
313                // If we're not allowed to sync (e.g. roaming policy), leave now
314                if (!ExchangeService.canAutoSync(mAccount)) {
315                    if (ExchangeService.onSecurityHold(mAccount)) {
316                        mExitStatus = EasSyncService.EXIT_SECURITY_FAILURE;
317                    } else {
318                        // Use backoff rules, etc.
319                        mExitStatus = EasSyncService.EXIT_IO_ERROR;
320                    }
321                    return;
322                }
323                userLog("Sending Account syncKey: ", mAccount.mSyncKey);
324                Serializer s = new Serializer();
325                s.start(Tags.FOLDER_FOLDER_SYNC).start(Tags.FOLDER_SYNC_KEY)
326                    .text(mAccount.mSyncKey).end().end().done();
327                EasResponse resp = sendHttpClientPost("FolderSync", s.toByteArray());
328                try {
329                    if (isStopped()) break;
330                    int code = resp.getStatus();
331                    if (code == HttpStatus.SC_OK) {
332                        if (!resp.isEmpty()) {
333                            InputStream is = resp.getInputStream();
334                            // Returns true if we need to sync again
335                            if (new FolderSyncParser(is,
336                                    new AccountSyncAdapter(this)).parse()) {
337                                continue;
338                            }
339                        }
340                    } else if (resp.isProvisionError()) {
341                        throw new CommandStatusException(CommandStatus.NEEDS_PROVISIONING);
342                    } else if (resp.isAuthError()) {
343                        mExitStatus = EasSyncService.EXIT_LOGIN_FAILURE;
344                        return;
345                    } else if (code == EAS_REDIRECT_CODE && canHandleAccountMailboxRedirect(resp)) {
346                        // This will cause a retry of the FolderSync
347                        continue;
348                    } else {
349                        userLog("FolderSync response error: ", code);
350                    }
351                } finally {
352                    resp.close();
353                }
354
355                // Change all push/hold boxes to push
356                cv.clear();
357                cv.put(Mailbox.SYNC_INTERVAL, Account.CHECK_INTERVAL_PUSH);
358                if (mContentResolver.update(Mailbox.CONTENT_URI, cv,
359                        WHERE_PUSH_HOLD_NOT_ACCOUNT_MAILBOX,
360                        new String[] {Long.toString(mAccount.mId)}) > 0) {
361                    userLog("Set push/hold boxes to push...");
362                }
363
364                // Before each run of the pingLoop, if this Account has a PolicySet, make sure it's
365                // active; otherwise, clear out the key/flag.  This should cause a provisioning
366                // error on the next POST, and start the security sequence over again
367                String key = mAccount.mSecuritySyncKey;
368                if (!TextUtils.isEmpty(key)) {
369                    Policy policy = Policy.restorePolicyWithId(mContext, mAccount.mPolicyKey);
370                    if ((policy != null) && !PolicyServiceProxy.isActive(mContext, policy)) {
371                        resetSecurityPolicies();
372                    }
373                }
374
375                // Wait for push notifications.
376                String threadName = Thread.currentThread().getName();
377                try {
378                    runPingLoop();
379                } catch (StaleFolderListException e) {
380                    // We break out if we get told about a stale folder list
381                    userLog("Ping interrupted; folder list requires sync...");
382                } catch (IllegalHeartbeatException e) {
383                    // If we're sending an illegal heartbeat, reset either the min or the max to
384                    // that heartbeat
385                    resetHeartbeats(e.mLegalHeartbeat);
386                } finally {
387                    Thread.currentThread().setName(threadName);
388                }
389            }
390        } catch (CommandStatusException e) {
391            // If the sync error is a provisioning failure (perhaps policies changed),
392            // let's try the provisioning procedure
393            // Provisioning must only be attempted for the account mailbox - trying to
394            // provision any other mailbox may result in race conditions and the
395            // creation of multiple policy keys.
396            int status = e.mStatus;
397            if (CommandStatus.isNeedsProvisioning(status)) {
398                if (!tryProvision(this)) {
399                    // Set the appropriate failure status
400                    mExitStatus = EasSyncService.EXIT_SECURITY_FAILURE;
401                    return;
402                }
403            } else if (CommandStatus.isDeniedAccess(status)) {
404                mExitStatus = EasSyncService.EXIT_ACCESS_DENIED;
405                return;
406            } else {
407                userLog("Unexpected status: " + CommandStatus.toString(status));
408                mExitStatus = EasSyncService.EXIT_EXCEPTION;
409            }
410        }
411    }
412
413    /**
414     * Reset either our minimum or maximum ping heartbeat to a heartbeat known to be legal
415     * @param legalHeartbeat a known legal heartbeat (from the EAS server)
416     */
417    /*package*/ void resetHeartbeats(int legalHeartbeat) {
418        userLog("Resetting min/max heartbeat, legal = " + legalHeartbeat);
419        // We are here because the current heartbeat (mPingHeartbeat) is invalid.  Depending on
420        // whether the argument is above or below the current heartbeat, we can infer the need to
421        // change either the minimum or maximum heartbeat
422        if (legalHeartbeat > mPingHeartbeat) {
423            // The legal heartbeat is higher than the ping heartbeat; therefore, our minimum was
424            // too low.  We respond by raising either or both of the minimum heartbeat or the
425            // force heartbeat to the argument value
426            if (mPingMinHeartbeat < legalHeartbeat) {
427                mPingMinHeartbeat = legalHeartbeat;
428            }
429            if (mPingForceHeartbeat < legalHeartbeat) {
430                mPingForceHeartbeat = legalHeartbeat;
431            }
432            // If our minimum is now greater than the max, bring them together
433            if (mPingMinHeartbeat > mPingMaxHeartbeat) {
434                mPingMaxHeartbeat = legalHeartbeat;
435            }
436        } else if (legalHeartbeat < mPingHeartbeat) {
437            // The legal heartbeat is lower than the ping heartbeat; therefore, our maximum was
438            // too high.  We respond by lowering the maximum to the argument value
439            mPingMaxHeartbeat = legalHeartbeat;
440            // If our maximum is now less than the minimum, bring them together
441            if (mPingMaxHeartbeat < mPingMinHeartbeat) {
442                mPingMinHeartbeat = legalHeartbeat;
443            }
444        }
445        // Set current heartbeat to the legal heartbeat
446        mPingHeartbeat = legalHeartbeat;
447        // Allow the heartbeat logic to run
448        mPingHeartbeatDropped = false;
449    }
450
451    private void pushFallback(long mailboxId) {
452        Mailbox mailbox = Mailbox.restoreMailboxWithId(mContext, mailboxId);
453        if (mailbox == null) {
454            return;
455        }
456        ContentValues cv = new ContentValues();
457        int mins = PING_FALLBACK_PIM;
458        if (mailbox.mType == Mailbox.TYPE_INBOX) {
459            mins = PING_FALLBACK_INBOX;
460        }
461        cv.put(Mailbox.SYNC_INTERVAL, mins);
462        mContentResolver.update(ContentUris.withAppendedId(Mailbox.CONTENT_URI, mailboxId),
463                cv, null, null);
464        errorLog("*** PING ERROR LOOP: Set " + mailbox.mDisplayName + " to " + mins
465                + " min sync");
466        ExchangeService.kick("push fallback");
467    }
468
469    /**
470     * Simplistic attempt to determine a NAT timeout, based on experience with various carriers
471     * and networks.  The string "reset by peer" is very common in these situations, so we look for
472     * that specifically.  We may add additional tests here as more is learned.
473     * @param message
474     * @return whether this message is likely associated with a NAT failure
475     */
476    private static boolean isLikelyNatFailure(String message) {
477        if (message == null) return false;
478        if (message.contains("reset by peer")) {
479            return true;
480        }
481        return false;
482    }
483
484    private void sleep(long ms, boolean runAsleep) {
485        if (runAsleep) {
486            ExchangeService.runAsleep(mMailboxId, ms + (5 * DateUtils.SECOND_IN_MILLIS));
487        }
488        try {
489            Thread.sleep(ms);
490        } catch (InterruptedException e) {
491            // Doesn't matter whether we stop early; it's the thought that counts
492        } finally {
493            if (runAsleep) {
494                ExchangeService.runAwake(mMailboxId);
495            }
496        }
497    }
498
499    protected EasResponse sendPing(byte[] bytes, int heartbeat) throws IOException {
500       Thread.currentThread().setName(mAccount.mDisplayName + ": Ping");
501       if (Eas.USER_LOG) {
502           userLog("Send ping, timeout: " + heartbeat + "s, high: " + mPingHighWaterMark + 's');
503       }
504       return sendHttpClientPost(EasSyncService.PING_COMMAND, new ByteArrayEntity(bytes),
505               (int)((heartbeat + 5) * DateUtils.SECOND_IN_MILLIS));
506    }
507
508    private void runPingLoop() throws IOException, StaleFolderListException,
509            IllegalHeartbeatException, CommandStatusException {
510        int pingHeartbeat = mPingHeartbeat;
511        userLog("runPingLoop");
512        // Do push for all sync services here
513        long endTime = System.currentTimeMillis() + (30 * DateUtils.MINUTE_IN_MILLIS);
514        HashMap<String, Integer> pingErrorMap = new HashMap<String, Integer>();
515        ArrayList<String> readyMailboxes = new ArrayList<String>();
516        ArrayList<String> notReadyMailboxes = new ArrayList<String>();
517        int pingWaitCount = 0;
518        long inboxId = -1;
519        android.accounts.Account amAccount = new android.accounts.Account(mAccount.mEmailAddress,
520                Eas.EXCHANGE_ACCOUNT_MANAGER_TYPE);
521        while ((System.currentTimeMillis() < endTime) && !isStopped()) {
522            // Count of pushable mailboxes
523            int pushCount = 0;
524            // Count of mailboxes that can be pushed right now
525            int canPushCount = 0;
526            // Count of uninitialized boxes
527            int uninitCount = 0;
528
529            Serializer s = new Serializer();
530            Cursor c = mContentResolver.query(Mailbox.CONTENT_URI, Mailbox.CONTENT_PROJECTION,
531                    MailboxColumns.ACCOUNT_KEY + '=' + mAccount.mId +
532                    AND_FREQUENCY_PING_PUSH_AND_NOT_ACCOUNT_MAILBOX, null, null);
533            if (c == null) throw new ProviderUnavailableException();
534            notReadyMailboxes.clear();
535            readyMailboxes.clear();
536            // Look for an inbox, and remember its id
537            if (inboxId == -1) {
538                inboxId = Mailbox.findMailboxOfType(mContext, mAccount.mId, Mailbox.TYPE_INBOX);
539            }
540            try {
541                // Loop through our pushed boxes seeing what is available to push
542                while (c.moveToNext()) {
543                    pushCount++;
544                    // Two requirements for push:
545                    // 1) ExchangeService tells us the mailbox is syncable (not running/not stopped)
546                    // 2) The syncKey isn't "0" (i.e. it's synced at least once)
547                    long mailboxId = c.getLong(Mailbox.CONTENT_ID_COLUMN);
548                    String mailboxName = c.getString(Mailbox.CONTENT_DISPLAY_NAME_COLUMN);
549
550                    // See what type of box we've got and get authority
551                    int mailboxType = c.getInt(Mailbox.CONTENT_TYPE_COLUMN);
552                    String authority = EmailContent.AUTHORITY;
553                    switch(mailboxType) {
554                        case Mailbox.TYPE_CALENDAR:
555                            authority = CalendarContract.AUTHORITY;
556                            break;
557                        case Mailbox.TYPE_CONTACTS:
558                            authority = ContactsContract.AUTHORITY;
559                            break;
560                    }
561
562                    // See whether we can ping for this mailbox
563                    int pingStatus;
564                    if (!ContentResolver.getSyncAutomatically(amAccount, authority)) {
565                        pingStatus = ExchangeService.PING_STATUS_DISABLED;
566                    } else {
567                        pingStatus = ExchangeService.pingStatus(mailboxId);
568
569                    }
570
571                    if (pingStatus == ExchangeService.PING_STATUS_OK) {
572                        String syncKey = c.getString(Mailbox.CONTENT_SYNC_KEY_COLUMN);
573                        if ((syncKey == null) || syncKey.equals("0")) {
574                            // We can't push until the initial sync is done
575                            pushCount--;
576                            uninitCount++;
577                            continue;
578                        }
579
580                        if (canPushCount++ == 0) {
581                            // Initialize the Ping command
582                            s.start(Tags.PING_PING)
583                                .data(Tags.PING_HEARTBEAT_INTERVAL,
584                                        Integer.toString(pingHeartbeat))
585                                .start(Tags.PING_FOLDERS);
586                        }
587
588                        String folderClass = getTargetCollectionClassFromCursor(c);
589                        s.start(Tags.PING_FOLDER)
590                            .data(Tags.PING_ID, c.getString(Mailbox.CONTENT_SERVER_ID_COLUMN))
591                            .data(Tags.PING_CLASS, folderClass)
592                            .end();
593                        readyMailboxes.add(mailboxName);
594                    } else if ((pingStatus == ExchangeService.PING_STATUS_RUNNING) ||
595                            (pingStatus == ExchangeService.PING_STATUS_WAITING)) {
596                        notReadyMailboxes.add(mailboxName);
597                    } else if (pingStatus == ExchangeService.PING_STATUS_UNABLE) {
598                        pushCount--;
599                        userLog(mailboxName, " in error state; ignore");
600                        continue;
601                    } else if (pingStatus == ExchangeService.PING_STATUS_DISABLED) {
602                        pushCount--;
603                        userLog(mailboxName, " disabled by user; ignore");
604                        continue;
605                    }
606                }
607            } finally {
608                c.close();
609            }
610
611            if (Eas.USER_LOG) {
612                if (!notReadyMailboxes.isEmpty()) {
613                    userLog("Ping not ready for: " + notReadyMailboxes);
614                }
615                if (!readyMailboxes.isEmpty()) {
616                    userLog("Ping ready for: " + readyMailboxes);
617                }
618            }
619
620            // If we've waited 10 seconds or more, just ping with whatever boxes are ready
621            // But use a shorter than normal heartbeat
622            boolean forcePing = !notReadyMailboxes.isEmpty() && (pingWaitCount > 5);
623
624            if ((canPushCount > 0) && ((canPushCount == pushCount) || forcePing)) {
625                // If all pingable boxes are ready for push, send Ping to the server
626                s.end().end().done();
627                pingWaitCount = 0;
628                mPostAborted = false;
629                mPostReset = false;
630
631                // If we've been stopped, this is a good time to return
632                if (isStopped()) return;
633
634                long pingTime = SystemClock.elapsedRealtime();
635                try {
636                    // Send the ping, wrapped by appropriate timeout/alarm
637                    if (forcePing) {
638                        userLog("Forcing ping after waiting for all boxes to be ready");
639                    }
640                    EasResponse resp =
641                        sendPing(s.toByteArray(), forcePing ? mPingForceHeartbeat : pingHeartbeat);
642
643                    try {
644                        int code = resp.getStatus();
645                        userLog("Ping response: ", code);
646
647                        // If we're not allowed to sync (e.g. roaming policy), terminate gracefully
648                        // now; otherwise we might start a sync based on the response
649                        if (!ExchangeService.canAutoSync(mAccount)) {
650                            stop();
651                        }
652
653                        // Return immediately if we've been asked to stop during the ping
654                        if (isStopped()) {
655                            userLog("Stopping pingLoop");
656                            return;
657                        }
658
659                        if (code == HttpStatus.SC_OK) {
660                            if (!resp.isEmpty()) {
661                                InputStream is = resp.getInputStream();
662                                int pingResult = parsePingResult(is, mContentResolver,
663                                        pingErrorMap);
664                                // If our ping completed (status = 1), and wasn't forced and we're
665                                // not at the maximum, try increasing timeout by two minutes
666                                if (pingResult == PROTOCOL_PING_STATUS_COMPLETED && !forcePing) {
667                                    if (pingHeartbeat > mPingHighWaterMark) {
668                                        mPingHighWaterMark = pingHeartbeat;
669                                        userLog("Setting high water mark at: ", mPingHighWaterMark);
670                                    }
671                                    if ((pingHeartbeat < mPingMaxHeartbeat) &&
672                                            !mPingHeartbeatDropped) {
673                                        pingHeartbeat += PING_HEARTBEAT_INCREMENT;
674                                        if (pingHeartbeat > mPingMaxHeartbeat) {
675                                            pingHeartbeat = mPingMaxHeartbeat;
676                                        }
677                                        userLog("Increase ping heartbeat to ", pingHeartbeat, "s");
678                                    }
679                                } else if (pingResult == PROTOCOL_PING_STATUS_BAD_PARAMETERS ||
680                                        pingResult == PROTOCOL_PING_STATUS_RETRY) {
681                                    // These errors appear to be server-related (I've seen a bad
682                                    // parameters result with known good parameters...)
683                                    userLog("Server error during Ping: " + pingResult);
684                                    // Act as if we have an IOException (backoff, etc.)
685                                    throw new IOException();
686                                }
687                                // Make sure to clear out any pending sync errors
688                                ExchangeService.removeFromSyncErrorMap(mMailboxId);
689                            } else {
690                                userLog("Ping returned empty result; throwing IOException");
691                                // Act as if we have an IOException (backoff, etc.)
692                                throw new IOException();
693                            }
694                        } else if (resp.isAuthError()) {
695                            mExitStatus = EasSyncService.EXIT_LOGIN_FAILURE;
696                            userLog("Authorization error during Ping: ", code);
697                            throw new IOException();
698                        }
699                    } finally {
700                        resp.close();
701                    }
702                } catch (IOException e) {
703                    String message = e.getMessage();
704                    // If we get the exception that is indicative of a NAT timeout and if we
705                    // haven't yet "fixed" the timeout, back off by two minutes and "fix" it
706                    boolean hasMessage = message != null;
707                    userLog("IOException runPingLoop: " + (hasMessage ? message : "[no message]"));
708                    if (mPostReset) {
709                        // Nothing to do in this case; this is ExchangeService telling us to try
710                        // another ping.
711                    } else if (mPostAborted || isLikelyNatFailure(message)) {
712                        long pingLength = SystemClock.elapsedRealtime() - pingTime;
713                        if ((pingHeartbeat > mPingMinHeartbeat) &&
714                                (pingHeartbeat > mPingHighWaterMark)) {
715                            pingHeartbeat -= PING_HEARTBEAT_INCREMENT;
716                            mPingHeartbeatDropped = true;
717                            if (pingHeartbeat < mPingMinHeartbeat) {
718                                pingHeartbeat = mPingMinHeartbeat;
719                            }
720                            userLog("Decreased ping heartbeat to ", pingHeartbeat, "s");
721                        } else if (mPostAborted) {
722                            // There's no point in throwing here; this can happen in two cases
723                            // 1) An alarm, which indicates minutes without activity; no sense
724                            //    backing off
725                            // 2) ExchangeService abort, due to sync of mailbox.  Again, we want to
726                            //    keep on trying to ping
727                            userLog("Ping aborted; retry");
728                        } else if (pingLength < 2000) {
729                            userLog("Abort or NAT type return < 2 seconds; throwing IOException");
730                            throw e;
731                        } else {
732                            userLog("NAT type IOException");
733                        }
734                    } else if (hasMessage && message.contains("roken pipe")) {
735                        // The "broken pipe" error (uppercase or lowercase "b") seems to be an
736                        // internal error, so let's not throw an exception (which leads to delays)
737                        // but rather simply run through the loop again
738                    } else {
739                        throw e;
740                    }
741                }
742            } else if (forcePing) {
743                // In this case, there aren't any boxes that are pingable, but there are boxes
744                // waiting (for IOExceptions)
745                userLog("pingLoop waiting 60s for any pingable boxes");
746                sleep(60 * DateUtils.SECOND_IN_MILLIS, true);
747            } else if (pushCount > 0) {
748                // If we want to Ping, but can't just yet, wait a little bit
749                // TODO Change sleep to wait and use notify from ExchangeService when a sync ends
750                sleep(2 * DateUtils.SECOND_IN_MILLIS, false);
751                pingWaitCount++;
752                //userLog("pingLoop waited 2s for: ", (pushCount - canPushCount), " box(es)");
753            } else if (uninitCount > 0) {
754                // In this case, we're doing an initial sync of at least one mailbox.  Since this
755                // is typically a one-time case, I'm ok with trying again every 10 seconds until
756                // we're in one of the other possible states.
757                userLog("pingLoop waiting for initial sync of ", uninitCount, " box(es)");
758                sleep(10 * DateUtils.SECOND_IN_MILLIS, true);
759            } else if (inboxId == -1) {
760                // In this case, we're still syncing mailboxes, so sleep for only a short time
761                sleep(45 * DateUtils.SECOND_IN_MILLIS, true);
762            } else {
763                // We've got nothing to do, so we'll check again in 20 minutes at which time
764                // we'll update the folder list, check for policy changes and/or remote wipe, etc.
765                // Let the device sleep in the meantime...
766                userLog(ACCOUNT_MAILBOX_SLEEP_TEXT);
767                sleep(ACCOUNT_MAILBOX_SLEEP_TIME, true);
768            }
769        }
770
771        // Save away the current heartbeat
772        mPingHeartbeat = pingHeartbeat;
773    }
774
775    private int parsePingResult(InputStream is, ContentResolver cr,
776            HashMap<String, Integer> errorMap)
777            throws IOException, StaleFolderListException, IllegalHeartbeatException,
778                CommandStatusException {
779        PingParser pp = new PingParser(is);
780        if (pp.parse()) {
781            // True indicates some mailboxes need syncing...
782            // syncList has the serverId's of the mailboxes...
783            mBindArguments[0] = Long.toString(mAccount.mId);
784            mPingChangeList = pp.getSyncList();
785            for (String serverId: mPingChangeList) {
786                mBindArguments[1] = serverId;
787                Cursor c = cr.query(Mailbox.CONTENT_URI, Mailbox.CONTENT_PROJECTION,
788                        WHERE_ACCOUNT_KEY_AND_SERVER_ID, mBindArguments, null);
789                if (c == null) throw new ProviderUnavailableException();
790                try {
791                    if (c.moveToFirst()) {
792
793                        /**
794                         * Check the boxes reporting changes to see if there really were any...
795                         * We do this because bugs in various Exchange servers can put us into a
796                         * looping behavior by continually reporting changes in a mailbox, even when
797                         * there aren't any.
798                         *
799                         * This behavior is seemingly random, and therefore we must code defensively
800                         * by backing off of push behavior when it is detected.
801                         *
802                         * One known cause, on certain Exchange 2003 servers, is acknowledged by
803                         * Microsoft, and the server hotfix for this case can be found at
804                         * http://support.microsoft.com/kb/923282
805                         */
806
807                        // Check the status of the last sync
808                        String status = c.getString(Mailbox.CONTENT_SYNC_STATUS_COLUMN);
809                        int type = ExchangeService.getStatusType(status);
810                        // This check should always be true...
811                        if (type == ExchangeService.SYNC_PING) {
812                            int changeCount = ExchangeService.getStatusChangeCount(status);
813                            if (changeCount > 0) {
814                                errorMap.remove(serverId);
815                            } else if (changeCount == 0) {
816                                // This means that a ping reported changes in error; we keep a count
817                                // of consecutive errors of this kind
818                                String name = c.getString(Mailbox.CONTENT_DISPLAY_NAME_COLUMN);
819                                Integer failures = errorMap.get(serverId);
820                                if (failures == null) {
821                                    userLog("Last ping reported changes in error for: ", name);
822                                    errorMap.put(serverId, 1);
823                                } else if (failures > MAX_PING_FAILURES) {
824                                    // We'll back off of push for this box
825                                    pushFallback(c.getLong(Mailbox.CONTENT_ID_COLUMN));
826                                    continue;
827                                } else {
828                                    userLog("Last ping reported changes in error for: ", name);
829                                    errorMap.put(serverId, failures + 1);
830                                }
831                            }
832                        }
833
834                        // If there were no problems with previous sync, we'll start another one
835                        ExchangeService.startManualSync(c.getLong(Mailbox.CONTENT_ID_COLUMN),
836                                ExchangeService.SYNC_PING, null);
837                    }
838                } finally {
839                    c.close();
840                }
841            }
842        }
843        return pp.getPingStatus();
844    }
845}
846