1/*
2 * Copyright 2018, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16#define DEBUG false  // STOPSHIP if true
17#include "Log.h"
18
19#include "StateTracker.h"
20#include "guardrail/StatsdStats.h"
21
22namespace android {
23namespace os {
24namespace statsd {
25
26using std::string;
27using std::unordered_set;
28using std::vector;
29
30StateTracker::StateTracker(const ConfigKey& key, const int64_t& id, const int index,
31                           const SimplePredicate& simplePredicate,
32                           const unordered_map<int64_t, int>& trackerNameIndexMap,
33                           const vector<Matcher> primaryKeys)
34    : ConditionTracker(id, index), mConfigKey(key), mPrimaryKeys(primaryKeys) {
35    if (simplePredicate.has_start()) {
36        auto pair = trackerNameIndexMap.find(simplePredicate.start());
37        if (pair == trackerNameIndexMap.end()) {
38            ALOGW("Start matcher %lld not found in the config", (long long)simplePredicate.start());
39            return;
40        }
41        mStartLogMatcherIndex = pair->second;
42        mTrackerIndex.insert(mStartLogMatcherIndex);
43    } else {
44        ALOGW("Condition %lld must have a start matcher", (long long)id);
45        return;
46    }
47
48    if (simplePredicate.has_dimensions()) {
49        translateFieldMatcher(simplePredicate.dimensions(), &mOutputDimensions);
50        if (mOutputDimensions.size() > 0) {
51            mSliced = true;
52            mDimensionTag = mOutputDimensions[0].mMatcher.getTag();
53        } else {
54            ALOGW("Condition %lld has invalid dimensions", (long long)id);
55            return;
56        }
57    } else {
58        ALOGW("Condition %lld being a state tracker, but has no dimension", (long long)id);
59        return;
60    }
61
62    if (simplePredicate.initial_value() == SimplePredicate_InitialValue_FALSE) {
63        mInitialValue = ConditionState::kFalse;
64    } else {
65        mInitialValue = ConditionState::kUnknown;
66    }
67
68    mNonSlicedConditionState = mInitialValue;
69    mInitialized = true;
70}
71
72StateTracker::~StateTracker() {
73    VLOG("~StateTracker()");
74}
75
76bool StateTracker::init(const vector<Predicate>& allConditionConfig,
77                        const vector<sp<ConditionTracker>>& allConditionTrackers,
78                        const unordered_map<int64_t, int>& conditionIdIndexMap,
79                        vector<bool>& stack) {
80    return mInitialized;
81}
82
83void StateTracker::dumpState() {
84    VLOG("StateTracker %lld DUMP:", (long long)mConditionId);
85    for (const auto& value : mSlicedState) {
86        VLOG("\t%s -> %s", value.first.toString().c_str(), value.second.toString().c_str());
87    }
88    VLOG("Last Changed to True: ");
89    for (const auto& value : mLastChangedToTrueDimensions) {
90        VLOG("%s", value.toString().c_str());
91    }
92    VLOG("Last Changed to False: ");
93    for (const auto& value : mLastChangedToFalseDimensions) {
94        VLOG("%s", value.toString().c_str());
95    }
96}
97
98bool StateTracker::hitGuardRail(const HashableDimensionKey& newKey) {
99    if (mSlicedState.find(newKey) != mSlicedState.end()) {
100        // if the condition is not sliced or the key is not new, we are good!
101        return false;
102    }
103    // 1. Report the tuple count if the tuple count > soft limit
104    if (mSlicedState.size() > StatsdStats::kDimensionKeySizeSoftLimit - 1) {
105        size_t newTupleCount = mSlicedState.size() + 1;
106        StatsdStats::getInstance().noteConditionDimensionSize(mConfigKey, mConditionId, newTupleCount);
107        // 2. Don't add more tuples, we are above the allowed threshold. Drop the data.
108        if (newTupleCount > StatsdStats::kDimensionKeySizeHardLimit) {
109            ALOGE("Predicate %lld dropping data for dimension key %s",
110                (long long)mConditionId, newKey.toString().c_str());
111            return true;
112        }
113    }
114    return false;
115}
116
117void StateTracker::evaluateCondition(const LogEvent& event,
118                                     const vector<MatchingState>& eventMatcherValues,
119                                     const vector<sp<ConditionTracker>>& mAllConditions,
120                                     vector<ConditionState>& conditionCache,
121                                     vector<bool>& conditionChangedCache) {
122    mLastChangedToTrueDimensions.clear();
123    mLastChangedToFalseDimensions.clear();
124    if (conditionCache[mIndex] != ConditionState::kNotEvaluated) {
125        // it has been evaluated.
126        VLOG("Yes, already evaluated, %lld %d", (long long)mConditionId, conditionCache[mIndex]);
127        return;
128    }
129
130    if (mStartLogMatcherIndex >= 0 &&
131        eventMatcherValues[mStartLogMatcherIndex] != MatchingState::kMatched) {
132        conditionCache[mIndex] =
133                mSlicedState.size() > 0 ? ConditionState::kTrue : ConditionState::kFalse;
134        conditionChangedCache[mIndex] = false;
135        return;
136    }
137
138    VLOG("StateTracker evaluate event %s", event.ToString().c_str());
139
140    // Primary key can exclusive fields must be simple fields. so there won't be more than
141    // one keys matched.
142    HashableDimensionKey primaryKey;
143    HashableDimensionKey state;
144    if ((mPrimaryKeys.size() > 0 && !filterValues(mPrimaryKeys, event.getValues(), &primaryKey)) ||
145        !filterValues(mOutputDimensions, event.getValues(), &state)) {
146        ALOGE("Failed to filter fields in the event?? panic now!");
147        conditionCache[mIndex] =
148                mSlicedState.size() > 0 ? ConditionState::kTrue : ConditionState::kFalse;
149        conditionChangedCache[mIndex] = false;
150        return;
151    }
152    hitGuardRail(primaryKey);
153
154    VLOG("StateTracker: key %s state %s", primaryKey.toString().c_str(), state.toString().c_str());
155
156    auto it = mSlicedState.find(primaryKey);
157    if (it == mSlicedState.end()) {
158        mSlicedState[primaryKey] = state;
159        conditionCache[mIndex] = ConditionState::kTrue;
160        mLastChangedToTrueDimensions.insert(state);
161        conditionChangedCache[mIndex] = true;
162    } else if (!(it->second == state)) {
163        mLastChangedToFalseDimensions.insert(it->second);
164        mLastChangedToTrueDimensions.insert(state);
165        mSlicedState[primaryKey] = state;
166        conditionCache[mIndex] = ConditionState::kTrue;
167        conditionChangedCache[mIndex] = true;
168    } else {
169        conditionCache[mIndex] = ConditionState::kTrue;
170        conditionChangedCache[mIndex] = false;
171    }
172
173    if (DEBUG) {
174        dumpState();
175    }
176    return;
177}
178
179void StateTracker::isConditionMet(
180        const ConditionKey& conditionParameters, const vector<sp<ConditionTracker>>& allConditions,
181        const vector<Matcher>& dimensionFields,
182        const bool isSubOutputDimensionFields,
183        const bool isPartialLink,
184        vector<ConditionState>& conditionCache,
185        std::unordered_set<HashableDimensionKey>& dimensionsKeySet) const {
186    if (conditionCache[mIndex] != ConditionState::kNotEvaluated) {
187        // it has been evaluated.
188        VLOG("Yes, already evaluated, %lld %d", (long long)mConditionId, conditionCache[mIndex]);
189        return;
190    }
191
192    const auto pair = conditionParameters.find(mConditionId);
193    if (pair == conditionParameters.end()) {
194        if (mSlicedState.size() > 0) {
195            conditionCache[mIndex] = ConditionState::kTrue;
196
197            for (const auto& state : mSlicedState) {
198                dimensionsKeySet.insert(state.second);
199            }
200        } else {
201            conditionCache[mIndex] = ConditionState::kUnknown;
202        }
203        return;
204    }
205
206    const auto& primaryKey = pair->second;
207    conditionCache[mIndex] = mInitialValue;
208    auto it = mSlicedState.find(primaryKey);
209    if (it != mSlicedState.end()) {
210        conditionCache[mIndex] = ConditionState::kTrue;
211        dimensionsKeySet.insert(it->second);
212    }
213}
214
215ConditionState StateTracker::getMetConditionDimension(
216        const std::vector<sp<ConditionTracker>>& allConditions,
217        const vector<Matcher>& dimensionFields,
218        const bool isSubOutputDimensionFields,
219        std::unordered_set<HashableDimensionKey>& dimensionsKeySet) const {
220    if (mSlicedState.size() > 0) {
221        for (const auto& state : mSlicedState) {
222            dimensionsKeySet.insert(state.second);
223        }
224        return ConditionState::kTrue;
225    }
226
227    return mInitialValue;
228}
229
230}  // namespace statsd
231}  // namespace os
232}  // namespace android