Files
mongo/db/clientcursor.h
2008-06-11 16:58:34 -04:00

70 lines
1.7 KiB
C++

/* clientcursor.h
Cursor -- and its derived classes -- are our internal cursors.
ClientCursor is a wrapper that represents a cursorid from our client
application's perspective.
*/
#pragma once
#include "../stdafx.h"
typedef long long CursorId;
class Cursor;
class ClientCursor;
typedef map<CursorId, ClientCursor*> CCById;
extern CCById clientCursorsById;
class ClientCursor {
friend class CursInspector;
DiskLoc _lastLoc; // use getter and setter not this.
static CursorId allocCursorId();
public:
ClientCursor() : cursorid( allocCursorId() ), pos(0) {
clientCursorsById.insert( make_pair(cursorid, this) );
}
~ClientCursor();
const CursorId cursorid;
string ns;
auto_ptr<JSMatcher> matcher;
auto_ptr<Cursor> c;
int pos;
DiskLoc lastLoc() const { return _lastLoc; }
void setLastLoc(DiskLoc);
auto_ptr< set<string> > filter; // which fields query wants returned
Message originalMessage; // this is effectively an auto ptr for data the matcher points to.
static bool erase(CursorId id) {
ClientCursor *cc = find(id);
if( cc ) {
delete cc;
return true;
}
return false;
}
static ClientCursor* find(CursorId id) {
CCById::iterator it = clientCursorsById.find(id);
if( it == clientCursorsById.end() ) {
cout << "ClientCursor::find(): cursor not found in map " << id << '\n';
return 0;
}
return it->second;
}
/* call when cursor's location changes so that we can update the
cursorsbylocation map. if you are locked and internally iterating, only
need to call when you are ready to "unlock".
*/
void updateLocation();
//private:
// void addToByLocation(DiskLoc cl);
void cleanupByLocation(DiskLoc loc);
//public:
// ClientCursor *nextAtThisLocation;
};