C++ BSONObj类代码示例

 v8::Handle<v8::Value> ThreadReturnData(V8Scope* scope, const v8::Arguments& args) {
     BSONObj data = thisConfig(scope, args)->returnData();
     return scope->mongoToV8Element(data.firstElement(), true);
 }

Status MMAPV1DatabaseCatalogEntry::renameCollection(OperationContext* txn,
                                                    StringData fromNS,
                                                    StringData toNS,
                                                    bool stayTemp) {
    Status s = _renameSingleNamespace(txn, fromNS, toNS, stayTemp);
    if (!s.isOK())
        return s;

    NamespaceDetails* details = _namespaceIndex.details(toNS);
    invariant(details);

    RecordStoreV1Base* systemIndexRecordStore = _getIndexRecordStore();
    auto cursor = systemIndexRecordStore->getCursor(txn);
    while (auto record = cursor->next()) {
        BSONObj oldIndexSpec = record->data.releaseToBson();
        if (fromNS != oldIndexSpec["ns"].valuestrsafe())
            continue;

        BSONObj newIndexSpec;
        {
            BSONObjBuilder b;
            BSONObjIterator i(oldIndexSpec);
            while (i.more()) {
                BSONElement e = i.next();
                if (strcmp(e.fieldName(), "ns") != 0)
                    b.append(e);
                else
                    b << "ns" << toNS;
            }
            newIndexSpec = b.obj();
        }

        StatusWith<RecordId> newIndexSpecLoc = systemIndexRecordStore->insertRecord(
            txn, newIndexSpec.objdata(), newIndexSpec.objsize(), false);
        if (!newIndexSpecLoc.isOK())
            return newIndexSpecLoc.getStatus();

        const std::string& indexName = oldIndexSpec.getStringField("name");

        {
            // Fix the IndexDetails pointer.
            int indexI = getCollectionCatalogEntry(toNS)->_findIndexNumber(txn, indexName);

            IndexDetails& indexDetails = details->idx(indexI);
            *txn->recoveryUnit()->writing(&indexDetails.info) =
                DiskLoc::fromRecordId(newIndexSpecLoc.getValue());
        }

        {
            // Move the underlying namespace.
            std::string oldIndexNs = IndexDescriptor::makeIndexNamespace(fromNS, indexName);
            std::string newIndexNs = IndexDescriptor::makeIndexNamespace(toNS, indexName);

            Status s = _renameSingleNamespace(txn, oldIndexNs, newIndexNs, false);
            if (!s.isOK())
                return s;
        }

        systemIndexRecordStore->deleteRecord(txn, record->id);
    }

    return Status::OK();
}

BSONObj* DBController::readBSON(StreamType* stream) {
	auto_ptr<BSONInputStream> is(new BSONInputStream(stream));
	BSONObj* res = is->readBSON();
	if (_logger->isDebug()) _logger->debug(3, "DBController read bson from disc: %s", res->toChar());
	return res;
}

TEST(MatchExpressionParserTest, ParseIntegerElementToNonNegativeLongRejectsNegative) {
    BSONObj query = BSON("" << -2LL);
    ASSERT_NOT_OK(
        MatchExpressionParser::parseIntegerElementToNonNegativeLong(query.firstElement()));
}

        void operator()( DBClientCursorBatchIterator &i ) {
            mongolock l( true );
            if ( context ) {
                context->relocked();
            }

            while( i.moreInCurrentBatch() ) {
                if ( n % 128 == 127 /*yield some*/ ) {
                    time_t now = time(0);
                    if( now - lastLog >= 60 ) { 
                        // report progress
                        if( lastLog )
                            log() << "clone " << to_collection << ' ' << n << endl;
                        lastLog = now;
                    }
                    mayInterrupt( _mayBeInterrupted );
                    dbtempreleaseif t( _mayYield );
                }

                BSONObj tmp = i.nextSafe();

                /* assure object is valid.  note this will slow us down a little. */
                if ( !tmp.valid() ) {
                    stringstream ss;
                    ss << "Cloner: skipping corrupt object from " << from_collection;
                    BSONElement e = tmp.firstElement();
                    try {
                        e.validate();
                        ss << " firstElement: " << e;
                    }
                    catch( ... ) {
                        ss << " firstElement corrupt";
                    }
                    out() << ss.str() << endl;
                    continue;
                }

                ++n;

                BSONObj js = tmp;
                if ( isindex ) {
                    assert( strstr(from_collection, "system.indexes") );
                    js = fixindex(tmp);
                    storedForLater->push_back( js.getOwned() );
                    continue;
                }

                try {
                    theDataFileMgr.insertWithObjMod(to_collection, js);
                    if ( logForRepl )
                        logOp("i", to_collection, js);

                    getDur().commitIfNeeded();
                }
                catch( UserException& e ) {
                    log() << "warning: exception cloning object in " << from_collection << ' ' << e.what() << " obj:" << js.toString() << '\n';
                }

                RARELY if ( time( 0 ) - saveLast > 60 ) {
                    log() << n << " objects cloned so far from collection " << from_collection << endl;
                    saveLast = time( 0 );
                }
            }
        }

        bool run( const string& dbname,
                  BSONObj& cmdObj,
                  int,
                  string& errmsg,
                  BSONObjBuilder& result,
                  bool ) {

            string ns;
            if ( !FieldParser::extract( cmdObj, nsField, &ns, &errmsg ) ) {
                return false;
            }

            if ( ns.size() == 0 ) {
                errmsg = "no namespace specified";
                return false;
            }

            vector<BSONObj> bounds;
            if ( !FieldParser::extract( cmdObj, boundsField, &bounds, &errmsg ) ) {
                return false;
            }

            if ( bounds.size() == 0 ) {
                errmsg = "no bounds were specified";
                return false;
            }

            if ( bounds.size() != 2 ) {
                errmsg = "only a min and max bound may be specified";
                return false;
            }

            BSONObj minKey = bounds[0];
            BSONObj maxKey = bounds[1];

            if ( minKey.isEmpty() ) {
                errmsg = "no min key specified";
                return false;
            }

            if ( maxKey.isEmpty() ) {
                errmsg = "no max key specified";
                return false;
            }

            //
            // This might be the first call from mongos, so we may need to pass the config and shard
            // information to initialize the shardingState.
            //

            string config;
            FieldParser::FieldState extracted = FieldParser::extract( cmdObj,
                                                                      configField,
                                                                      &config,
                                                                      &errmsg );
            if ( !extracted ) return false;
            if ( extracted != FieldParser::FIELD_NONE ) {
                ShardingState::initialize( config );
            }
            else if ( !shardingState.enabled() ) {
                errmsg =
                    "sharding state must be enabled or config server specified to merge chunks";
                return false;
            }

            // ShardName is optional, but might not be set yet
            string shardName;
            extracted = FieldParser::extract( cmdObj, shardNameField, &shardName, &errmsg );

            if ( !extracted ) return false;
            if ( extracted != FieldParser::FIELD_NONE ) {
                shardingState.gotShardName( shardName );
            }

            //
            // Epoch is optional, and if not set indicates we should use the latest epoch
            //

            OID epoch;
            if ( !FieldParser::extract( cmdObj, epochField, &epoch, &errmsg ) ) {
                return false;
            }

            return mergeChunks( NamespaceString( ns ), minKey, maxKey, epoch, true, &errmsg );
        }

/* ****************************************************************************
*
* mongoUnsubscribeContextAvailability - 
*/
HttpStatusCode mongoUnsubscribeContextAvailability
(
  UnsubscribeContextAvailabilityRequest*   requestP,
  UnsubscribeContextAvailabilityResponse*  responseP,
  const std::string&                       tenant
)
{
  bool        reqSemTaken;
  std::string err;

  reqSemTake(__FUNCTION__, "ngsi9 unsubscribe request", SemWriteOp, &reqSemTaken);

  LM_T(LmtMongo, ("Unsubscribe Context Availability"));

  /* No matter if success or failure, the subscriptionId in the response is always the one
   * in the request */
  responseP->subscriptionId = requestP->subscriptionId;

  /* Look for document */
  BSONObj sub;
  OID     id;

  if (!safeGetSubId(requestP->subscriptionId, &id, &(responseP->statusCode)))
  {
    reqSemGive(__FUNCTION__, "ngsi9 unsubscribe request (safeGetSubId fail)", reqSemTaken);
    if (responseP->statusCode.code == SccContextElementNotFound)
    {
      // FIXME: doubt: invalid OID format? Or, subscription not found?
      std::string details = std::string("invalid OID format: '") + requestP->subscriptionId.get() + "'";
      alarmMgr.badInput(clientIp, details);
    }
    else // SccReceiverInternalError
    {
      LM_E(("Runtime Error (exception getting OID: %s)", responseP->statusCode.details.c_str()));
    }
    return SccOk;
  }

  if (!collectionFindOne(getSubscribeContextAvailabilityCollectionName(tenant), BSON("_id" << id), &sub, &err))
  {
    reqSemGive(__FUNCTION__, "ngsi9 unsubscribe request (mongo db exception)", reqSemTaken);
    responseP->statusCode.fill(SccReceiverInternalError, err);
    return SccOk;
  }
  alarmMgr.dbErrorReset();

  if (sub.isEmpty())
  {
    responseP->statusCode.fill(SccContextElementNotFound);
    reqSemGive(__FUNCTION__, "ngsi9 unsubscribe request (no subscriptions)", reqSemTaken);
    return SccOk;
  }

  /* Remove document in MongoDB */
  // FIXME: I would prefer to do the find and remove in a single operation. Is the some similar
  // to findAndModify for this?  
  if (!collectionRemove(getSubscribeContextAvailabilityCollectionName(tenant), BSON("_id" << OID(requestP->subscriptionId.get())), &err))
  {
    reqSemGive(__FUNCTION__, "ngsi9 unsubscribe request (mongo db exception)", reqSemTaken);
    responseP->statusCode.fill(SccReceiverInternalError, err);
    return SccOk;
  }

  reqSemGive(__FUNCTION__, "ngsi9 unsubscribe request", reqSemTaken);
  responseP->statusCode.fill(SccOk);
  return SccOk;
}

    UpdateResult update(UpdateRequest& request, UpdateDriver* driver) {

        const NamespaceString& nsString = request.getNamespaceString();

        validateUpdate( nsString.ns().c_str(), request.getUpdates(), request.getQuery() );

        NamespaceDetails* nsDetails = nsdetails( nsString.ns() );
        NamespaceDetailsTransient* nsDetailsTransient =
            &NamespaceDetailsTransient::get( nsString.ns().c_str() );

        OpDebug& debug = request.getDebug();

        // TODO: This seems a bit circuitious.
        debug.updateobj = request.getUpdates();

        driver->refreshIndexKeys( nsDetailsTransient->indexKeys() );

        shared_ptr<Cursor> cursor = getOptimizedCursor(
            nsString.ns(), request.getQuery(), BSONObj(), request.getQueryPlanSelectionPolicy() );

        // If the update was marked with '$isolated' (a.k.a '$atomic'), we are not allowed to
        // yield while evaluating the update loop below.
        //
        // TODO: Old code checks this repeatedly within the update loop. Is that necessary? It seems
        // that once atomic should be always atomic.
        const bool isolated =
            cursor->ok() &&
            cursor->matcher() &&
            cursor->matcher()->docMatcher().atomic();

        // The 'cursor' the optimizer gave us may contain query plans that generate duplicate
        // diskloc's. We set up here the mechanims that will prevent us from processing those
        // twice if we see them. We also set up a 'ClientCursor' so that we can support
        // yielding.
        //
        // TODO: Is it valid to call this on a non-ok cursor?
        const bool dedupHere = cursor->autoDedup();

        //
        // We'll start assuming we have one or more documents for this update. (Othwerwise,
        // we'll fallback to upserting.)
        //

        // We record that this will not be an upsert, in case a mod doesn't want to be applied
        // when in strict update mode.
        driver->setContext( ModifierInterface::ExecInfo::UPDATE_CONTEXT );

        // Let's fetch each of them and pipe them through the update expression, making sure to
        // keep track of the necessary stats. Recall that we'll be pulling documents out of
        // cursors and some of them do not deduplicate the entries they generate. We have
        // deduping logic in here, too -- for now.
        unordered_set<DiskLoc, DiskLoc::Hasher> seenLocs;
        int numMatched = 0;
        debug.nscanned = 0;

        Client& client = cc();

        mutablebson::Document doc;

        // If we are going to be yielding, we will need a ClientCursor scoped to this loop. We
        // only loop as long as the underlying cursor is OK.
        for ( auto_ptr<ClientCursor> clientCursor; cursor->ok(); ) {

            // If we haven't constructed a ClientCursor, and if the client allows us to throw
            // page faults, and if we are referring to a location that is likely not in
            // physical memory, then throw a PageFaultException. The entire operation will be
            // restarted.
            if ( clientCursor.get() == NULL &&
                 client.allowedToThrowPageFaultException() &&
                 !cursor->currLoc().isNull() &&
                 !cursor->currLoc().rec()->likelyInPhysicalMemory() ) {
                // We should never throw a PFE if we have already updated items.
                dassert((numMatched == 0) || (numMatched == debug.nupdateNoops));
                throw PageFaultException( cursor->currLoc().rec() );
            }

            if ( !isolated && debug.nscanned != 0 ) {

                // We are permitted to yield. To do so we need a ClientCursor, so create one
                // now if we have not yet done so.
                if ( !clientCursor.get() )
                    clientCursor.reset(
                        new ClientCursor( QueryOption_NoCursorTimeout, cursor, nsString.ns() ) );

                // Ask the client cursor to yield. We get two bits of state back: whether or not
                // we yielded, and whether or not we correctly recovered from yielding.
                bool yielded = false;
                const bool recovered = clientCursor->yieldSometimes(
                    ClientCursor::WillNeed, &yielded );

                if ( !recovered ) {
                    // If we failed to recover from the yield, then the ClientCursor is already
                    // gone. Release it so we don't destroy it a second time.
                    clientCursor.release();
                    break;
                }

                if ( !cursor->ok() ) {
                    // If the cursor died while we were yielded, just get out of the update loop.
                    break;
//.........这里部分代码省略.........

// static
Status ClearFilters::clear(OperationContext* txn,
                           QuerySettings* querySettings,
                           PlanCache* planCache,
                           const std::string& ns,
                           const BSONObj& cmdObj) {
    invariant(querySettings);

    // According to the specification, the planCacheClearFilters command runs in two modes:
    // - clear all hints; or
    // - clear hints for single query shape when a query shape is described in the
    //   command arguments.
    if (cmdObj.hasField("query")) {
        auto statusWithCQ = PlanCacheCommand::canonicalize(txn, ns, cmdObj);
        if (!statusWithCQ.isOK()) {
            return statusWithCQ.getStatus();
        }

        unique_ptr<CanonicalQuery> cq = std::move(statusWithCQ.getValue());
        querySettings->removeAllowedIndices(planCache->computeKey(*cq));

        // Remove entry from plan cache
        planCache->remove(*cq);

        LOG(0) << "Removed index filter on " << ns << " " << cq->toStringShort();

        return Status::OK();
    }

    // If query is not provided, make sure sort and projection are not in arguments.
    // We do not want to clear the entire cache inadvertently when the user
    // forgot to provide a value for "query".
    if (cmdObj.hasField("sort") || cmdObj.hasField("projection")) {
        return Status(ErrorCodes::BadValue, "sort or projection provided without query");
    }

    // Get entries from query settings. We need to remove corresponding entries from the plan
    // cache shortly.
    OwnedPointerVector<AllowedIndexEntry> entries;
    entries.mutableVector() = querySettings->getAllAllowedIndices();

    // OK to proceed with clearing entire cache.
    querySettings->clearAllowedIndices();

    const NamespaceString nss(ns);
    const ExtensionsCallbackReal extensionsCallback(txn, &nss);

    // Remove corresponding entries from plan cache.
    // Admin hints affect the planning process directly. If there were
    // plans generated as a result of applying index filter, these need to be
    // invalidated. This allows the planner to re-populate the plan cache with
    // non-filtered indexed solutions next time the query is run.
    // Resolve plan cache key from (query, sort, projection) in query settings entry.
    // Concurrency note: There's no harm in removing plan cache entries one at at time.
    // Only way that PlanCache::remove() can fail is when the query shape has been removed from
    // the cache by some other means (re-index, collection info reset, ...). This is OK since
    // that's the intended effect of calling the remove() function with the key from the hint entry.
    for (vector<AllowedIndexEntry*>::const_iterator i = entries.begin(); i != entries.end(); ++i) {
        AllowedIndexEntry* entry = *i;
        invariant(entry);

        // Create canonical query.
        auto qr = stdx::make_unique<QueryRequest>(nss);
        qr->setFilter(entry->query);
        qr->setSort(entry->sort);
        qr->setProj(entry->projection);
        auto statusWithCQ = CanonicalQuery::canonicalize(txn, std::move(qr), extensionsCallback);
        invariantOK(statusWithCQ.getStatus());
        std::unique_ptr<CanonicalQuery> cq = std::move(statusWithCQ.getValue());

        // Remove plan cache entry.
        planCache->remove(*cq);
    }

    LOG(0) << "Removed all index filters for collection: " << ns;

    return Status::OK();
}

    void handle_modify(DBClientBase *client, DBOperation *operation)
    {
        // First, we have to format our findandmodify.
        BSONObjBuilder sets;
        bool has_sets = false;
        BSONObjBuilder unsets;
        bool has_unsets = false;
        for(auto it  = operation->set_fields().begin();
            it != operation->set_fields().end(); ++it) {
            stringstream fieldname;
            fieldname << "fields." << it->first->get_name();
            if(it->second.empty()) {
                unsets << fieldname.str() << true;
                has_unsets = true;
            } else {
                DatagramPtr dg = Datagram::create();
                dg->add_data(it->second);
                DatagramIterator dgi(dg);
                sets << fieldname.str() << bamboo2bson(it->first->get_type(), dgi)["_"];
                has_sets = true;
            }
        }

        BSONObjBuilder updates_b;
        if(has_sets) {
            updates_b << "$set" << sets.obj();
        }
        if(has_unsets) {
            updates_b << "$unset" << unsets.obj();
        }
        BSONObj updates = updates_b.obj();

        // Also format any criteria for the change:
        BSONObjBuilder query_b;
        query_b << "_id" << operation->doid();
        for(auto it  = operation->criteria_fields().begin();
            it != operation->criteria_fields().end(); ++it) {
            stringstream fieldname;
            fieldname << "fields." << it->first->get_name();
            if(it->second.empty()) {
                query_b << fieldname.str() << BSON("$exists" << false);
            } else {
                DatagramPtr dg = Datagram::create();
                dg->add_data(it->second);
                DatagramIterator dgi(dg);
                query_b << fieldname.str() << bamboo2bson(it->first->get_type(), dgi)["_"];
            }
        }
        BSONObj query = query_b.obj();

        m_log->trace() << "Performing updates to " << operation->doid()
                       << ": " << updates << endl;
        m_log->trace() << "Query is: " << query << endl;

        BSONObj result;
        bool success;
        try {
            success = client->runCommand(
                          m_db,
                          BSON("findandmodify" << "astron.objects"
                               << "query" << query
                               << "update" << updates),
                          result);
        } catch(mongo::DBException &e) {
            m_log->error() << "Unexpected error while modifying "
                           << operation->doid() << ": " << e.what() << endl;
            operation->on_failure();
            return;
        }

        m_log->trace() << "Update result: " << result << endl;

        BSONObj obj;
        if(!success || result["value"].isNull()) {
            // Okay, something didn't work right. If we had criteria, let's
            // try to fetch the object without the criteria to see if it's a
            // criteria mismatch or a missing DOID.
            if(!operation->criteria_fields().empty()) {
                try {
                    obj = client->findOne(m_obj_collection,
                                          BSON("_id" << operation->doid()));
                } catch(mongo::DBException &e) {
                    m_log->error() << "Unexpected error while modifying "
                                   << operation->doid() << ": " << e.what() << endl;
                    operation->on_failure();
                    return;
                }
                if(!obj.isEmpty()) {
                    // There's the problem. Now we can send back a snapshot:
                    DBObjectSnapshot *snap = format_snapshot(operation->doid(), obj);
                    if(snap && operation->verify_class(snap->m_dclass)) {
                        operation->on_criteria_mismatch(snap);
                        return;
                    } else {
                        // Something else weird happened with our snapshot;
                        // either the class wasn't recognized or it was the
                        // wrong class. Either way, an error has been logged,
                        // and we need to fail the operation.
                        operation->on_failure();
                        return;
//.........这里部分代码省略.........

        void operator()( DBClientCursorBatchIterator &i ) {
            Lock::GlobalWrite lk;
            if ( context ) {
                context->relocked();
            }

            while( i.moreInCurrentBatch() ) {
                if ( n % 128 == 127 /*yield some*/ ) {
                    time_t now = time(0);
                    if( now - lastLog >= 60 ) { 
                        // report progress
                        if( lastLog )
                            log() << "clone " << to_collection << ' ' << n << endl;
                        lastLog = now;
                    }
                    mayInterrupt( _mayBeInterrupted );
                    dbtempreleaseif t( _mayYield );
                }

                BSONObj tmp = i.nextSafe();

                /* assure object is valid.  note this will slow us down a little. */
                if ( !tmp.valid() ) {
                    stringstream ss;
                    ss << "Cloner: skipping corrupt object from " << from_collection;
                    BSONElement e = tmp.firstElement();
                    try {
                        e.validate();
                        ss << " firstElement: " << e;
                    }
                    catch( ... ) {
                        ss << " firstElement corrupt";
                    }
                    out() << ss.str() << endl;
                    continue;
                }

                ++n;

                BSONObj js = tmp;
                if ( isindex ) {
                    verify( strstr(from_collection, "system.indexes") );
                    js = fixindex(tmp);
                    storedForLater->push_back( js.getOwned() );
                    continue;
                }

                try {
                    // add keys for presorting
                    DiskLoc loc = theDataFileMgr.insertWithObjMod(to_collection, js);
                    loc.assertOk();
                    if (_sortersForIndex != NULL) {
                        // add key to SortersForNS
                        for (SortersForIndex::iterator iSorter = _sortersForIndex->begin();
                             iSorter != _sortersForIndex->end();
                             ++iSorter) {
                            iSorter->second.preSortPhase.addKeys(iSorter->second.spec, js,
                                                                 loc, false);
                        }
                    }
                    if ( logForRepl )
                        logOp("i", to_collection, js);

                    getDur().commitIfNeeded();
                }
                catch( UserException& e ) {
                    error() << "error: exception cloning object in " << from_collection << ' ' << e.what() << " obj:" << js.toString() << '\n';
                    throw;
                }

                RARELY if ( time( 0 ) - saveLast > 60 ) {
                    log() << n << " objects cloned so far from collection " << from_collection << endl;
                    saveLast = time( 0 );
                }
            }
        }

void FTSIndexFormat::getKeys(const FTSSpec& spec, const BSONObj& obj, BSONObjSet* keys) {
    int extraSize = 0;
    vector<BSONElement> extrasBefore;
    vector<BSONElement> extrasAfter;

    // Compute the non FTS key elements for the prefix.
    for (unsigned i = 0; i < spec.numExtraBefore(); i++) {
        auto indexedElement = extractNonFTSKeyElement(obj, spec.extraBefore(i));
        extrasBefore.push_back(indexedElement);
        extraSize += indexedElement.size();
    }

    // Compute the non FTS key elements for the suffix.
    for (unsigned i = 0; i < spec.numExtraAfter(); i++) {
        auto indexedElement = extractNonFTSKeyElement(obj, spec.extraAfter(i));
        extrasAfter.push_back(indexedElement);
        extraSize += indexedElement.size();
    }

    TermFrequencyMap term_freqs;
    spec.scoreDocument(obj, &term_freqs);

    // create index keys from raw scores
    // only 1 per string

    // TODO SERVER-36440: Completely remove this limit in 4.3.
    if (serverGlobalParams.featureCompatibility.isVersionInitialized() &&
        serverGlobalParams.featureCompatibility.getVersion() ==
            ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo40) {
        uassert(16732,
                str::stream() << "too many unique keys for a single document to"
                              << " have a text index, max is "
                              << term_freqs.size()
                              << obj["_id"],
                term_freqs.size() <= 400000);
    }

    long long keyBSONSize = 0;
    const int MaxKeyBSONSizeMB = 4;

    for (TermFrequencyMap::const_iterator i = term_freqs.begin(); i != term_freqs.end(); ++i) {
        const string& term = i->first;
        double weight = i->second;

        // guess the total size of the btree entry based on the size of the weight, term tuple
        int guess = 5 /* bson overhead */ + 10 /* weight */ + 8 /* term overhead */ +
            /* term size (could be truncated/hashed) */
            guessTermSize(term, spec.getTextIndexVersion()) + extraSize;

        BSONObjBuilder b(guess);  // builds a BSON object with guess length.
        for (unsigned k = 0; k < extrasBefore.size(); k++) {
            b.appendAs(extrasBefore[k], "");
        }
        _appendIndexKey(b, weight, term, spec.getTextIndexVersion());
        for (unsigned k = 0; k < extrasAfter.size(); k++) {
            b.appendAs(extrasAfter[k], "");
        }
        BSONObj res = b.obj();

        verify(guess >= res.objsize());

        keys->insert(res);
        keyBSONSize += res.objsize();

        // TODO SERVER-36440: Completely remove this limit in 4.3.
        if (serverGlobalParams.featureCompatibility.isVersionInitialized() &&
            serverGlobalParams.featureCompatibility.getVersion() ==
                ServerGlobalParams::FeatureCompatibility::Version::kFullyDowngradedTo40) {
            uassert(16733,
                    str::stream() << "trying to index text where term list is too big, max is "
                                  << MaxKeyBSONSizeMB
                                  << "mb "
                                  << obj["_id"],
                    keyBSONSize <= (MaxKeyBSONSizeMB * 1024 * 1024));
        }
    }
}

Status ChunkManagerTargeter::targetUpdate(OperationContext* txn,
                                          const BatchedUpdateDocument& updateDoc,
                                          vector<ShardEndpoint*>* endpoints) const {
    //
    // Update targeting may use either the query or the update.  This is to support save-style
    // updates, of the form:
    //
    // coll.update({ _id : xxx }, { _id : xxx, shardKey : 1, foo : bar }, { upsert : true })
    //
    // Because drivers do not know the shard key, they can't pull the shard key automatically
    // into the query doc, and to correctly support upsert we must target a single shard.
    //
    // The rule is simple - If the update is replacement style (no '$set'), we target using the
    // update.  If the update is replacement style, we target using the query.
    //
    // If we have the exact shard key in either the query or replacement doc, we target using
    // that extracted key.
    //

    BSONObj query = updateDoc.getQuery();
    BSONObj updateExpr = updateDoc.getUpdateExpr();

    UpdateType updateType = getUpdateExprType(updateDoc.getUpdateExpr());

    if (updateType == UpdateType_Unknown) {
        return Status(ErrorCodes::UnsupportedFormat,
                      stream() << "update document " << updateExpr
                               << " has mixed $operator and non-$operator style fields");
    }

    BSONObj shardKey;

    if (_manager) {
        //
        // Sharded collections have the following futher requirements for targeting:
        //
        // Upserts must be targeted exactly by shard key.
        // Non-multi updates must be targeted exactly by shard key *or* exact _id.
        //

        // Get the shard key
        if (updateType == UpdateType_OpStyle) {
            // Target using the query
            StatusWith<BSONObj> status =
                _manager->getShardKeyPattern().extractShardKeyFromQuery(query);

            // Bad query
            if (!status.isOK())
                return status.getStatus();

            shardKey = status.getValue();
        } else {
            // Target using the replacement document
            shardKey = _manager->getShardKeyPattern().extractShardKeyFromDoc(updateExpr);
        }

        //
        // Extra sharded update validation
        //

        if (updateDoc.getUpsert()) {
            // Sharded upserts *always* need to be exactly targeted by shard key
            if (shardKey.isEmpty()) {
                return Status(ErrorCodes::ShardKeyNotFound,
                              stream() << "upsert " << updateDoc.toBSON()
                                       << " does not contain shard key for pattern "
                                       << _manager->getShardKeyPattern().toString());
            }

            // Also check shard key size on upsert
            Status status = ShardKeyPattern::checkShardKeySize(shardKey);
            if (!status.isOK())
                return status;
        }

        // Validate that single (non-multi) sharded updates are targeted by shard key or _id
        if (!updateDoc.getMulti() && shardKey.isEmpty() && !isExactIdQuery(updateDoc.getQuery())) {
            return Status(ErrorCodes::ShardKeyNotFound,
                          stream() << "update " << updateDoc.toBSON()
                                   << " does not contain _id or shard key for pattern "
                                   << _manager->getShardKeyPattern().toString());
        }
    }

    // Target the shard key, query, or replacement doc
    if (!shardKey.isEmpty()) {
        // We can't rely on our query targeting to be exact
        ShardEndpoint* endpoint = NULL;
        Status result =
            targetShardKey(txn, shardKey, (query.objsize() + updateExpr.objsize()), &endpoint);
        endpoints->push_back(endpoint);
        return result;
    } else if (updateType == UpdateType_OpStyle) {
        return targetQuery(query, endpoints);
    } else {
        return targetDoc(updateExpr, endpoints);
    }
}

    DiskLoc _repairExtent( Database* db , string ns, bool forward , DiskLoc eLoc , Writer& w ) {
        LogIndentLevel lil;

        if ( eLoc.getOfs() <= 0 ) {
            error() << "invalid extent ofs: " << eLoc.getOfs() << endl;
            return DiskLoc();
        }


        MongoDataFile * mdf = db->getFile( eLoc.a() );

        Extent * e = mdf->debug_getExtent( eLoc );
        if ( ! e->isOk() ) {
            warning() << "Extent not ok magic: " << e->magic << " going to try to continue" << endl;
        }

        log() << "length:" << e->length << endl;

        LogIndentLevel lil2;

        set<DiskLoc> seen;

        DiskLoc loc = forward ? e->firstRecord : e->lastRecord;
        while ( ! loc.isNull() ) {

            if ( ! seen.insert( loc ).second ) {
                error() << "infinite loop in extend, seen: " << loc << " before" << endl;
                break;
            }

            if ( loc.getOfs() <= 0 ) {
                error() << "offset is 0 for record which should be impossible" << endl;
                break;
            }
            log(1) << loc << endl;
            Record* rec = loc.rec();
            BSONObj obj;
            try {
                obj = loc.obj();
                assert( obj.valid() );
                LOG(1) << obj << endl;
                w( obj );
            }
            catch ( std::exception& e ) {
                log() << "found invalid document @ " << loc << " " << e.what() << endl;
                if ( ! obj.isEmpty() ) {
                    try {
                        BSONElement e = obj.firstElement();
                        stringstream ss;
                        ss << "first element: " << e;
                        log() << ss.str();
                    }
                    catch ( std::exception& ) {
                    }
                }
            }
            loc = forward ? rec->getNext( loc ) : rec->getPrev( loc );
        }
        return forward ? e->xnext : e->xprev;

    }

    int run() {

        if ( hasParam( "repair" ) ) {
            warning() << "repair is a work in progress" << endl;
            return repair();
        }

        {
            string q = getParam("query");
            if ( q.size() )
                _query = fromjson( q );
        }

        string opLogName = "";
        unsigned long long opLogStart = 0;
        if (hasParam("oplog")) {
            if (hasParam("query") || hasParam("db") || hasParam("collection")) {
                cout << "oplog mode is only supported on full dumps" << endl;
                return -1;
            }


            BSONObj isMaster;
            conn("true").simpleCommand("admin", &isMaster, "isMaster");

            if (isMaster.hasField("hosts")) { // if connected to replica set member
                opLogName = "local.oplog.rs";
            }
            else {
                opLogName = "local.oplog.$main";
                if ( ! isMaster["ismaster"].trueValue() ) {
                    cout << "oplog mode is only supported on master or replica set member" << endl;
                    return -1;
                }
            }

            auth("local");

            BSONObj op = conn(true).findOne(opLogName, Query().sort("$natural", -1), 0, QueryOption_SlaveOk);
            if (op.isEmpty()) {
                cout << "No operations in oplog. Please ensure you are connecting to a master." << endl;
                return -1;
            }

            assert(op["ts"].type() == Timestamp);
            opLogStart = op["ts"]._numberLong();
        }

        // check if we're outputting to stdout
        string out = getParam("out");
        if ( out == "-" ) {
            if ( _db != "" && _coll != "" ) {
                writeCollectionStdout( _db+"."+_coll );
                return 0;
            }
            else {
                cout << "You must specify database and collection to print to stdout" << endl;
                return -1;
            }
        }

        _usingMongos = isMongos();

        path root( out );
        string db = _db;

        if ( db == "" ) {
            cout << "all dbs" << endl;
            auth( "admin" );

            BSONObj res = conn( true ).findOne( "admin.$cmd" , BSON( "listDatabases" << 1 ) );
            if ( ! res["databases"].isABSONObj() ) {
                error() << "output of listDatabases isn't what we expected, no 'databases' field:\n" << res << endl;
                return -2;
            }
            BSONObj dbs = res["databases"].embeddedObjectUserCheck();
            set<string> keys;
            dbs.getFieldNames( keys );
            for ( set<string>::iterator i = keys.begin() ; i != keys.end() ; i++ ) {
                string key = *i;

                if ( ! dbs[key].isABSONObj() ) {
                    error() << "database field not an object key: " << key << " value: " << dbs[key] << endl;
                    return -3;
                }

                BSONObj dbobj = dbs[key].embeddedObjectUserCheck();

                const char * dbName = dbobj.getField( "name" ).valuestr();
                if ( (string)dbName == "local" )
                    continue;

                go ( dbName , root / dbName );
            }
        }
        else {
            auth( db );
            go( db , root / db );
        }

//.........这里部分代码省略.........