summaryrefslogtreecommitdiff
path: root/src/mongo/db/exec/working_set.cpp
blob: 9db2c75093b7d75460ff4e1b0e67dbc049f811e3 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
/**
 *    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 <http://www.gnu.org/licenses/>.
 *
 *    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/working_set.h"

#include "mongo/db/index/index_descriptor.h"

namespace mongo {

    WorkingSet::MemberHolder::MemberHolder() : member(NULL) { }
    WorkingSet::MemberHolder::~MemberHolder() {}

    WorkingSet::WorkingSet() : _freeList(INVALID_ID) { }

    WorkingSet::~WorkingSet() {
        for (size_t i = 0; i < _data.size(); i++) {
            delete _data[i].member;
        }
    }

    WorkingSetID WorkingSet::allocate() {
        if (_freeList == INVALID_ID) {
            // The free list is empty so we need to make a single new WSM to return. This relies on
            // vector::resize being amortized O(1) for efficient allocation. Note that the free list
            // remains empty until something is returned by a call to free().
            WorkingSetID id = _data.size();
            _data.resize(_data.size() + 1);
            _data.back().nextFreeOrSelf = id;
            _data.back().member = new WorkingSetMember();
            return id;
        }

        // Pop the head off the free list and return it.
        WorkingSetID id = _freeList;
        _freeList = _data[id].nextFreeOrSelf;
        _data[id].nextFreeOrSelf = id; // set to self to mark as in-use
        return id;
    }

    void WorkingSet::free(const WorkingSetID& i) {
        MemberHolder& holder = _data[i];
        verify(i < _data.size()); // ID has been allocated.
        verify(holder.nextFreeOrSelf == i); // ID currently in use.

        // Free resources and push this WSM to the head of the freelist.
        holder.member->clear();
        holder.nextFreeOrSelf = _freeList;
        _freeList = i;
    }

    void WorkingSet::flagForReview(const WorkingSetID& i) {
        WorkingSetMember* member = get(i);
        verify(WorkingSetMember::OWNED_OBJ == member->state);
        _flagged.insert(i);
    }

    const unordered_set<WorkingSetID>& WorkingSet::getFlagged() const {
        return _flagged;
    }

    bool WorkingSet::isFlagged(WorkingSetID id) const {
        invariant(id < _data.size());
        return _flagged.end() != _flagged.find(id);
    }

    WorkingSetMember::WorkingSetMember() : state(WorkingSetMember::INVALID) { }

    WorkingSetMember::~WorkingSetMember() { }

    void WorkingSetMember::clear() {
        for (size_t i = 0; i < WSM_COMPUTED_NUM_TYPES; i++) {
            _computed[i].reset();
        }

        keyData.clear();
        obj = BSONObj();
        state = WorkingSetMember::INVALID;
    }

    bool WorkingSetMember::hasLoc() const {
        return state == LOC_AND_IDX || state == LOC_AND_UNOWNED_OBJ;
    }

    bool WorkingSetMember::hasObj() const {
        return hasOwnedObj() || hasUnownedObj();
    }

    bool WorkingSetMember::hasOwnedObj() const {
        return state == OWNED_OBJ;
    }

    bool WorkingSetMember::hasUnownedObj() const {
        return state == LOC_AND_UNOWNED_OBJ;
    }

    bool WorkingSetMember::hasComputed(const WorkingSetComputedDataType type) const {
        return _computed[type];
    }

    const WorkingSetComputedData* WorkingSetMember::getComputed(const WorkingSetComputedDataType type) const {
        verify(_computed[type]);
        return _computed[type].get();
    }

    void WorkingSetMember::addComputed(WorkingSetComputedData* data) {
        verify(!hasComputed(data->type()));
        _computed[data->type()].reset(data);
    }

    bool WorkingSetMember::getFieldDotted(const string& field, BSONElement* out) const {
        // If our state is such that we have an object, use it.
        if (hasObj()) {
            *out = obj.getFieldDotted(field);
            return true;
        }

        // Our state should be such that we have index data/are covered.
        for (size_t i = 0; i < keyData.size(); ++i) {
            BSONObjIterator keyPatternIt(keyData[i].indexKeyPattern);
            BSONObjIterator keyDataIt(keyData[i].keyData);

            while (keyPatternIt.more()) {
                BSONElement keyPatternElt = keyPatternIt.next();
                verify(keyDataIt.more());
                BSONElement keyDataElt = keyDataIt.next();

                if (field == keyPatternElt.fieldName()) {
                    *out = keyDataElt;
                    return true;
                }
            }
        }

        return false;
    }

}  // namespace mongo