1 /*
2 * Copyright (C) 2017 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
17 #include "Log.h"
18
19 #include "CombinationLogMatchingTracker.h"
20 #include "matchers/matcher_util.h"
21
22 namespace android {
23 namespace os {
24 namespace statsd {
25
26 using std::set;
27 using std::unordered_map;
28 using std::vector;
29
CombinationLogMatchingTracker(const int64_t & id,const int index)30 CombinationLogMatchingTracker::CombinationLogMatchingTracker(const int64_t& id, const int index)
31 : LogMatchingTracker(id, index) {
32 }
33
~CombinationLogMatchingTracker()34 CombinationLogMatchingTracker::~CombinationLogMatchingTracker() {
35 }
36
init(const vector<AtomMatcher> & allLogMatchers,const vector<sp<LogMatchingTracker>> & allTrackers,const unordered_map<int64_t,int> & matcherMap,vector<bool> & stack)37 bool CombinationLogMatchingTracker::init(const vector<AtomMatcher>& allLogMatchers,
38 const vector<sp<LogMatchingTracker>>& allTrackers,
39 const unordered_map<int64_t, int>& matcherMap,
40 vector<bool>& stack) {
41 if (mInitialized) {
42 return true;
43 }
44
45 // mark this node as visited in the recursion stack.
46 stack[mIndex] = true;
47
48 AtomMatcher_Combination matcher = allLogMatchers[mIndex].combination();
49
50 // LogicalOperation is missing in the config
51 if (!matcher.has_operation()) {
52 return false;
53 }
54
55 mLogicalOperation = matcher.operation();
56
57 if (mLogicalOperation == LogicalOperation::NOT && matcher.matcher_size() != 1) {
58 return false;
59 }
60
61 for (const auto& child : matcher.matcher()) {
62 auto pair = matcherMap.find(child);
63 if (pair == matcherMap.end()) {
64 ALOGW("Matcher %lld not found in the config", (long long)child);
65 return false;
66 }
67
68 int childIndex = pair->second;
69
70 // if the child is a visited node in the recursion -> circle detected.
71 if (stack[childIndex]) {
72 ALOGE("Circle detected in matcher config");
73 return false;
74 }
75
76 if (!allTrackers[childIndex]->init(allLogMatchers, allTrackers, matcherMap, stack)) {
77 ALOGW("child matcher init failed %lld", (long long)child);
78 return false;
79 }
80
81 mChildren.push_back(childIndex);
82
83 const set<int>& childTagIds = allTrackers[childIndex]->getAtomIds();
84 mAtomIds.insert(childTagIds.begin(), childTagIds.end());
85 }
86
87 mInitialized = true;
88 // unmark this node in the recursion stack.
89 stack[mIndex] = false;
90 return true;
91 }
92
onLogEvent(const LogEvent & event,const vector<sp<LogMatchingTracker>> & allTrackers,vector<MatchingState> & matcherResults)93 void CombinationLogMatchingTracker::onLogEvent(const LogEvent& event,
94 const vector<sp<LogMatchingTracker>>& allTrackers,
95 vector<MatchingState>& matcherResults) {
96 // this event has been processed.
97 if (matcherResults[mIndex] != MatchingState::kNotComputed) {
98 return;
99 }
100
101 if (mAtomIds.find(event.GetTagId()) == mAtomIds.end()) {
102 matcherResults[mIndex] = MatchingState::kNotMatched;
103 return;
104 }
105
106 // evaluate children matchers if they haven't been evaluated.
107 for (const int childIndex : mChildren) {
108 if (matcherResults[childIndex] == MatchingState::kNotComputed) {
109 const sp<LogMatchingTracker>& child = allTrackers[childIndex];
110 child->onLogEvent(event, allTrackers, matcherResults);
111 }
112 }
113
114 bool matched = combinationMatch(mChildren, mLogicalOperation, matcherResults);
115 matcherResults[mIndex] = matched ? MatchingState::kMatched : MatchingState::kNotMatched;
116 }
117
118 } // namespace statsd
119 } // namespace os
120 } // namespace android
121