QueryResult* getMore(const char *ns, int ntoreturn, long long cursorid , stringstream& ss) {
ClientCursor *cc = ClientCursor::find(cursorid);
int bufSize = 512;
if ( cc ){
bufSize += sizeof( QueryResult );
bufSize += ( ntoreturn ? 4 : 1 ) * 1024 * 1024;
}
BufBuilder b( bufSize );
b.skip(sizeof(QueryResult));
int resultFlags = 0;
int start = 0;
int n = 0;
if ( !cc ) {
log() << "getMore: cursorid not found " << ns << " " << cursorid << endl;
cursorid = 0;
resultFlags = QueryResult::ResultFlag_CursorNotFound;
}
else {
ss << " query: " << cc->query << " ";
start = cc->pos;
Cursor *c = cc->c.get();
c->checkLocation();
while ( 1 ) {
if ( !c->ok() ) {
if ( c->tailable() ) {
if ( c->advance() ) {
continue;
}
break;
}
bool ok = ClientCursor::erase(cursorid);
assert(ok);
cursorid = 0;
cc = 0;
break;
}
if ( !cc->matcher->matches(c->currKey(), c->currLoc() ) ) {
}
else {
//out() << "matches " << c->currLoc().toString() << '\n';
if( c->getsetdup(c->currLoc()) ) {
//out() << " but it's a dup \n";
}
else {
BSONObj js = c->current();
fillQueryResultFromObj(b, cc->filter.get(), js);
n++;
if ( (ntoreturn>0 && (n >= ntoreturn || b.len() > MaxBytesToReturnToClientAtOnce)) ||
(ntoreturn==0 && b.len()>1*1024*1024) ) {
c->advance();
cc->pos += n;
//cc->updateLocation();
break;
}
}
}
c->advance();
}
if ( cc ) {
cc->updateLocation();
cc->mayUpgradeStorage();
}
}
QueryResult *qr = (QueryResult *) b.buf();
qr->len = b.len();
qr->setOperation(opReply);
qr->resultFlags() = resultFlags;
qr->cursorId = cursorid;
qr->startingFrom = start;
qr->nReturned = n;
b.decouple();
return qr;
}
QueryResult* processGetMore(const char* ns,
int ntoreturn,
long long cursorid,
CurOp& curop,
int pass,
bool& exhaust,
bool* isCursorAuthorized ) {
bool hasRunner = false;
// Scoped to kill the pin after seeing if the runner's there.
{
// See if there's a runner. We do this until agg. is behind a Runner instead of a CC.
ClientCursorPin p(cursorid);
ClientCursor *cc = p.c();
if (NULL != cc && NULL != cc->getRunner()) {
hasRunner = true;
}
}
if (hasRunner) {
return newGetMore(ns, ntoreturn, cursorid, curop, pass, exhaust,
isCursorAuthorized);
}
exhaust = false;
int bufSize = 512 + sizeof( QueryResult ) + MaxBytesToReturnToClientAtOnce;
BufBuilder b( bufSize );
b.skip(sizeof(QueryResult));
int resultFlags = ResultFlag_AwaitCapable;
int start = 0;
int n = 0;
scoped_ptr<Client::ReadContext> ctx(new Client::ReadContext(ns));
// call this readlocked so state can't change
replVerifyReadsOk();
ClientCursorPin p(cursorid);
ClientCursor *cc = p.c();
if ( unlikely(!cc) ) {
LOGSOME << "getMore: cursorid not found " << ns << " " << cursorid << endl;
cursorid = 0;
resultFlags = ResultFlag_CursorNotFound;
}
else {
// Some internal users create a ClientCursor with a Runner. Don't crash if this
// happens. Instead, hand them off to the new framework.
if (NULL != cc->getRunner()) {
p.release();
return newGetMore(ns, ntoreturn, cursorid, curop, pass, exhaust, isCursorAuthorized);
}
// check for spoofing of the ns such that it does not match the one originally there for the cursor
uassert(14833, "auth error", str::equals(ns, cc->ns().c_str()));
*isCursorAuthorized = true;
// This must be done after auth check to ensure proper cleanup.
uassert(16951, "failing getmore due to set failpoint",
!MONGO_FAIL_POINT(getMoreError));
// If the operation that spawned this cursor had a time limit set, apply leftover
// time to this getmore.
curop.setMaxTimeMicros( cc->getLeftoverMaxTimeMicros() );
killCurrentOp.checkForInterrupt(); // May trigger maxTimeAlwaysTimeOut fail point.
if ( pass == 0 )
cc->updateSlaveLocation( curop );
int queryOptions = cc->queryOptions();
curop.debug().query = cc->query();
curop.setQuery( cc->query() );
start = cc->pos();
Cursor *c = cc->c();
if (!c->requiresLock()) {
// make sure it won't be destroyed under us
fassert(16952, !c->shouldDestroyOnNSDeletion());
fassert(16953, !c->supportYields());
ctx.reset(); // unlocks
}
c->recoverFromYield();
DiskLoc last;
// This metadata may be stale, but it's the state of chunking when the cursor was
// created.
CollectionMetadataPtr metadata = cc->getCollMetadata();
KeyPattern keyPattern( metadata ? metadata->getKeyPattern() : BSONObj() );
while ( 1 ) {
if ( !c->ok() ) {
if ( c->tailable() ) {
// when a tailable cursor hits "EOF", ok() goes false, and current() is
// null. however advance() can still be retries as a reactivation attempt.
// when there is new data, it will return true. that's what we are doing
// here.
if ( c->advance() )
continue;
if( n == 0 && (queryOptions & QueryOption_AwaitData) && pass < 1000 ) {
return 0;
}
break;
}
p.release();
bool ok = ClientCursor::erase(cursorid);
verify(ok);
cursorid = 0;
cc = 0;
break;
}
MatchDetails details;
if ( cc->fields && cc->fields->getArrayOpType() == Projection::ARRAY_OP_POSITIONAL ) {
// field projection specified, and contains an array operator
details.requestElemMatchKey();
}
// in some cases (clone collection) there won't be a matcher
if ( !c->currentMatches( &details ) ) {
}
else if ( metadata && !metadata->keyBelongsToMe( extractKey(c, keyPattern ) ) ) {
LOG(2) << "cursor skipping document in un-owned chunk: " << c->current()
<< endl;
}
else {
if( c->getsetdup(c->currLoc()) ) {
//out() << " but it's a dup \n";
}
else {
last = c->currLoc();
n++;
// Fill out the fields requested by the query.
const Projection::KeyOnly *keyFieldsOnly = c->keyFieldsOnly();
if ( keyFieldsOnly ) {
fillQueryResultFromObj( b, 0, keyFieldsOnly->hydrate(
c->currKey() ), &details );
}
else {
DiskLoc loc = c->currLoc();
fillQueryResultFromObj( b, cc->fields.get(), c->current(), &details,
( ( cc->pq.get() && cc->pq->showDiskLoc() ) ? &loc : 0 ) );
}
if ( ( ntoreturn && n >= ntoreturn ) || b.len() > MaxBytesToReturnToClientAtOnce ) {
c->advance();
cc->incPos( n );
break;
}
}
}
c->advance();
if ( ! cc->yieldSometimes( ( c->ok() && c->keyFieldsOnly() ) ?
ClientCursor::DontNeed : ClientCursor::WillNeed ) ) {
ClientCursor::erase(cursorid);
cursorid = 0;
cc = 0;
break;
}
}
if ( cc ) {
if ( c->supportYields() ) {
ClientCursor::YieldData data;
verify( cc->prepareToYield( data ) );
}
else {
cc->c()->noteLocation();
}
cc->storeOpForSlave( last );
exhaust = cc->queryOptions() & QueryOption_Exhaust;
// If the getmore had a time limit, remaining time is "rolled over" back to the
// cursor (for use by future getmore ops).
cc->setLeftoverMaxTimeMicros( curop.getRemainingMaxTimeMicros() );
}
}
QueryResult *qr = (QueryResult *) b.buf();
qr->len = b.len();
qr->setOperation(opReply);
qr->_resultFlags() = resultFlags;
qr->cursorId = cursorid;
qr->startingFrom = start;
qr->nReturned = n;
b.decouple();
return qr;
}
QueryResult* processGetMore(const char *ns, int ntoreturn, long long cursorid , CurOp& curop, int pass, bool& exhaust ) {
exhaust = false;
ClientCursor::Pointer p(cursorid);
ClientCursor *cc = p.c();
int bufSize = 512 + sizeof( QueryResult ) + MaxBytesToReturnToClientAtOnce;
BufBuilder b( bufSize );
b.skip(sizeof(QueryResult));
int resultFlags = ResultFlag_AwaitCapable;
int start = 0;
int n = 0;
if ( unlikely(!cc) ) {
LOGSOME << "getMore: cursorid not found " << ns << " " << cursorid << endl;
cursorid = 0;
resultFlags = ResultFlag_CursorNotFound;
}
else {
// check for spoofing of the ns such that it does not match the one originally there for the cursor
uassert(14833, "auth error", str::equals(ns, cc->ns().c_str()));
if ( pass == 0 )
cc->updateSlaveLocation( curop );
int queryOptions = cc->queryOptions();
curop.debug().query = cc->query();
start = cc->pos();
Cursor *c = cc->c();
c->recoverFromYield();
DiskLoc last;
scoped_ptr<Projection::KeyOnly> keyFieldsOnly;
if ( cc->modifiedKeys() == false && cc->isMultiKey() == false && cc->fields )
keyFieldsOnly.reset( cc->fields->checkKey( cc->indexKeyPattern() ) );
// This manager may be stale, but it's the state of chunking when the cursor was created.
ShardChunkManagerPtr manager = cc->getChunkManager();
while ( 1 ) {
if ( !c->ok() ) {
if ( c->tailable() ) {
/* when a tailable cursor hits "EOF", ok() goes false, and current() is null. however
advance() can still be retries as a reactivation attempt. when there is new data, it will
return true. that's what we are doing here.
*/
if ( c->advance() )
continue;
if( n == 0 && (queryOptions & QueryOption_AwaitData) && pass < 1000 ) {
return 0;
}
break;
}
p.release();
bool ok = ClientCursor::erase(cursorid);
verify(ok);
cursorid = 0;
cc = 0;
break;
}
// in some cases (clone collection) there won't be a matcher
if ( !c->currentMatches() ) {
}
else if ( manager && ! manager->belongsToMe( cc ) ){
LOG(2) << "cursor skipping document in un-owned chunk: " << c->current() << endl;
}
else {
if( c->getsetdup(c->currLoc()) ) {
//out() << " but it's a dup \n";
}
else {
last = c->currLoc();
n++;
if ( keyFieldsOnly ) {
fillQueryResultFromObj(b, 0, keyFieldsOnly->hydrate( c->currKey() ) );
}
else {
BSONObj js = c->current();
// show disk loc should be part of the main query, not in an $or clause, so this should be ok
fillQueryResultFromObj(b, cc->fields.get(), js, ( cc->pq.get() && cc->pq->showDiskLoc() ? &last : 0));
}
if ( ( ntoreturn && n >= ntoreturn ) || b.len() > MaxBytesToReturnToClientAtOnce ) {
c->advance();
cc->incPos( n );
break;
}
}
}
c->advance();
if ( ! cc->yieldSometimes( ClientCursor::MaybeCovered ) ) {
ClientCursor::erase(cursorid);
cursorid = 0;
cc = 0;
p.deleted();
break;
}
}
if ( cc ) {
if ( c->supportYields() ) {
ClientCursor::YieldData data;
verify( cc->prepareToYield( data ) );
}
else {
cc->c()->noteLocation();
}
cc->mayUpgradeStorage();
cc->storeOpForSlave( last );
exhaust = cc->queryOptions() & QueryOption_Exhaust;
}
}
QueryResult *qr = (QueryResult *) b.buf();
qr->len = b.len();
qr->setOperation(opReply);
qr->_resultFlags() = resultFlags;
qr->cursorId = cursorid;
qr->startingFrom = start;
qr->nReturned = n;
b.decouple();
return qr;
}
