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::string;
28 using std::unique_ptr;
29 using std::unordered_map;
30 using std::vector;
31
CombinationLogMatchingTracker(const int64_t & id,const int index)32 CombinationLogMatchingTracker::CombinationLogMatchingTracker(const int64_t& id, const int index)
33 : LogMatchingTracker(id, index) {
34 }
35
~CombinationLogMatchingTracker()36 CombinationLogMatchingTracker::~CombinationLogMatchingTracker() {
37 }
38
init(const vector<AtomMatcher> & allLogMatchers,const vector<sp<LogMatchingTracker>> & allTrackers,const unordered_map<int64_t,int> & matcherMap,vector<bool> & stack)39 bool CombinationLogMatchingTracker::init(const vector<AtomMatcher>& allLogMatchers,
40 const vector<sp<LogMatchingTracker>>& allTrackers,
41 const unordered_map<int64_t, int>& matcherMap,
42 vector<bool>& stack) {
43 if (mInitialized) {
44 return true;
45 }
46
47 // mark this node as visited in the recursion stack.
48 stack[mIndex] = true;
49
50 AtomMatcher_Combination matcher = allLogMatchers[mIndex].combination();
51
52 // LogicalOperation is missing in the config
53 if (!matcher.has_operation()) {
54 return false;
55 }
56
57 mLogicalOperation = matcher.operation();
58
59 if (mLogicalOperation == LogicalOperation::NOT && matcher.matcher_size() != 1) {
60 return false;
61 }
62
63 for (const auto& child : matcher.matcher()) {
64 auto pair = matcherMap.find(child);
65 if (pair == matcherMap.end()) {
66 ALOGW("Matcher %lld not found in the config", (long long)child);
67 return false;
68 }
69
70 int childIndex = pair->second;
71
72 // if the child is a visited node in the recursion -> circle detected.
73 if (stack[childIndex]) {
74 ALOGE("Circle detected in matcher config");
75 return false;
76 }
77
78 if (!allTrackers[childIndex]->init(allLogMatchers, allTrackers, matcherMap, stack)) {
79 ALOGW("child matcher init failed %lld", (long long)child);
80 return false;
81 }
82
83 mChildren.push_back(childIndex);
84
85 const set<int>& childTagIds = allTrackers[childIndex]->getAtomIds();
86 mAtomIds.insert(childTagIds.begin(), childTagIds.end());
87 }
88
89 mInitialized = true;
90 // unmark this node in the recursion stack.
91 stack[mIndex] = false;
92 return true;
93 }
94
onLogEvent(const LogEvent & event,const vector<sp<LogMatchingTracker>> & allTrackers,vector<MatchingState> & matcherResults)95 void CombinationLogMatchingTracker::onLogEvent(const LogEvent& event,
96 const vector<sp<LogMatchingTracker>>& allTrackers,
97 vector<MatchingState>& matcherResults) {
98 // this event has been processed.
99 if (matcherResults[mIndex] != MatchingState::kNotComputed) {
100 return;
101 }
102
103 if (mAtomIds.find(event.GetTagId()) == mAtomIds.end()) {
104 matcherResults[mIndex] = MatchingState::kNotMatched;
105 return;
106 }
107
108 // evaluate children matchers if they haven't been evaluated.
109 for (const int childIndex : mChildren) {
110 if (matcherResults[childIndex] == MatchingState::kNotComputed) {
111 const sp<LogMatchingTracker>& child = allTrackers[childIndex];
112 child->onLogEvent(event, allTrackers, matcherResults);
113 }
114 }
115
116 bool matched = combinationMatch(mChildren, mLogicalOperation, matcherResults);
117 matcherResults[mIndex] = matched ? MatchingState::kMatched : MatchingState::kNotMatched;
118 }
119
120 } // namespace statsd
121 } // namespace os
122 } // namespace android
123