/**
* Copyright (C) 2013 10gen Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see .
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#include "mongo/db/exec/or.h"
#include "mongo/db/exec/filter.h"
namespace mongo {
OrStage::OrStage(WorkingSet* ws, bool dedup, const MatchExpression* filter)
: _ws(ws), _filter(filter), _currentChild(0), _dedup(dedup) { }
OrStage::~OrStage() {
for (size_t i = 0; i < _children.size(); ++i) {
delete _children[i];
}
}
void OrStage::addChild(PlanStage* child) { _children.push_back(child); }
bool OrStage::isEOF() { return _currentChild >= _children.size(); }
PlanStage::StageState OrStage::work(WorkingSetID* out) {
++_commonStats.works;
if (isEOF()) { return PlanStage::IS_EOF; }
if (0 == _specificStats.matchTested.size()) {
_specificStats.matchTested = vector(_children.size(), 0);
}
WorkingSetID id;
StageState childStatus = _children[_currentChild]->work(&id);
if (PlanStage::ADVANCED == childStatus) {
WorkingSetMember* member = _ws->get(id);
verify(member->hasLoc());
// If we're deduping...
if (_dedup) {
++_specificStats.dupsTested;
// ...and we've seen the DiskLoc before
if (_seen.end() != _seen.find(member->loc)) {
// ...drop it.
++_specificStats.dupsDropped;
_ws->free(id);
++_commonStats.needTime;
return PlanStage::NEED_TIME;
}
else {
// Otherwise, note that we've seen it.
_seen.insert(member->loc);
}
}
if (Filter::passes(member, _filter)) {
if (NULL != _filter) {
++_specificStats.matchTested[_currentChild];
}
// Match! return it.
*out = id;
++_commonStats.advanced;
return PlanStage::ADVANCED;
}
else {
// Does not match, try again.
_ws->free(id);
++_commonStats.needTime;
return PlanStage::NEED_TIME;
}
}
else if (PlanStage::IS_EOF == childStatus) {
// Done with _currentChild, move to the next one.
++_currentChild;
// Maybe we're out of children.
if (isEOF()) {
return PlanStage::IS_EOF;
}
else {
++_commonStats.needTime;
return PlanStage::NEED_TIME;
}
}
else {
if (PlanStage::NEED_FETCH == childStatus) {
++_commonStats.needFetch;
}
else if (PlanStage::NEED_TIME == childStatus) {
++_commonStats.needTime;
}
// NEED_TIME, ERROR, NEED_YIELD, pass them up.
return childStatus;
}
}
void OrStage::prepareToYield() {
++_commonStats.yields;
for (size_t i = 0; i < _children.size(); ++i) {
_children[i]->prepareToYield();
}
}
void OrStage::recoverFromYield() {
++_commonStats.unyields;
for (size_t i = 0; i < _children.size(); ++i) {
_children[i]->recoverFromYield();
}
}
void OrStage::invalidate(const DiskLoc& dl) {
++_commonStats.invalidates;
if (isEOF()) { return; }
for (size_t i = 0; i < _children.size(); ++i) {
_children[i]->invalidate(dl);
}
// If we see DL again it is not the same record as it once was so we still want to
// return it.
if (_dedup) {
unordered_set::iterator it = _seen.find(dl);
if (_seen.end() != it) {
++_specificStats.locsForgotten;
_seen.erase(dl);
}
}
}
PlanStageStats* OrStage::getStats() {
_commonStats.isEOF = isEOF();
auto_ptr ret(new PlanStageStats(_commonStats));
ret->setSpecific(_specificStats);
for (size_t i = 0; i < _children.size(); ++i) {
ret->children.push_back(_children[i]->getStats());
}
return ret.release();
}
} // namespace mongo