1 /* 2 * Copyright (C) 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 17 #ifndef SRC_TRACED_PROBES_ANDROID_LOG_ANDROID_LOG_DATA_SOURCE_H_ 18 #define SRC_TRACED_PROBES_ANDROID_LOG_ANDROID_LOG_DATA_SOURCE_H_ 19 20 #include <unordered_map> 21 #include <unordered_set> 22 #include <vector> 23 24 #include "perfetto/ext/base/paged_memory.h" 25 #include "perfetto/ext/base/scoped_file.h" 26 #include "perfetto/ext/base/string_view.h" 27 #include "perfetto/ext/base/unix_socket.h" 28 #include "perfetto/ext/base/weak_ptr.h" 29 #include "perfetto/tracing/core/forward_decls.h" 30 #include "src/traced/probes/probes_data_source.h" 31 32 namespace perfetto { 33 34 class TraceWriter; 35 namespace base { 36 class TaskRunner; 37 } 38 39 namespace protos { 40 namespace pbzero { 41 class AndroidLogPacket; 42 class AndroidLogPacket_LogEvent; 43 } // namespace pbzero 44 } // namespace protos 45 46 class AndroidLogDataSource : public ProbesDataSource { 47 public: 48 static const ProbesDataSource::Descriptor descriptor; 49 50 struct Stats { 51 uint64_t num_total = 0; // Total number of log entries received. 52 uint64_t num_failed = 0; // Parser failures. 53 uint64_t num_skipped = 0; // Messages skipped due to filters. 54 }; 55 56 // One EventFormat == one line of /system/etc/event-log-tags. 57 struct EventFormat { 58 std::string name; 59 std::vector<std::string> fields; 60 }; 61 62 AndroidLogDataSource(DataSourceConfig, 63 base::TaskRunner*, 64 TracingSessionID, 65 std::unique_ptr<TraceWriter> writer); 66 67 ~AndroidLogDataSource() override; 68 69 // ProbesDataSource implementation. 70 void Start() override; 71 void Flush(FlushRequestID, std::function<void()> callback) override; 72 73 // Reads the contents of /system/etc/event-log-tags. Virtual for testing. 74 virtual std::string ReadEventLogDefinitions(); 75 76 // Connects to the /dev/socket/logdr socket. Virtual for testing. 77 virtual base::UnixSocketRaw ConnectLogdrSocket(); 78 79 // Parses the contents of ReadEventLogDefinitions(). 80 void ParseEventLogDefinitions(); 81 82 const EventFormat* GetEventFormat(int id) const; stats()83 const Stats& stats() const { return stats_; } 84 base::WeakPtr<AndroidLogDataSource> GetWeakPtr() const; 85 86 private: 87 void EnableSocketWatchTask(bool); 88 void OnSocketDataAvailable(); 89 void ReadLogSocket(); 90 91 // Parses one line of /system/etc/event-log-tags. 92 bool ParseEventLogDefinitionLine(char* line, size_t len); 93 94 // Parses a textual (i.e. tag + message) event, which is the majority of 95 // log events. All buffers but the LID_EVENTS contain text events. 96 // If parsing fails returns false and leaves the |out_evt| field unset. 97 // If parsing succeeds returns true and: 98 // - If the event is skipped due to filters, |out_evt| is left unset. 99 // - If a new event is aded to the packet, |out_evt| is set to that. 100 bool ParseTextEvent(const char* start, 101 const char* end, 102 protos::pbzero::AndroidLogPacket* packet, 103 protos::pbzero::AndroidLogPacket_LogEvent** out_evt); 104 105 // Parses a binary event from the "events" buffer. 106 // If parsing fails returns false and leaves the |out_evt| field unset. 107 // If parsing succeeds returns true and: 108 // - If the event is skipped due to filters, |out_evt| is left unset. 109 // - If a new event is aded to the packet, |out_evt| is set to that. 110 bool ParseBinaryEvent(const char* start, 111 const char* end, 112 protos::pbzero::AndroidLogPacket* packet, 113 protos::pbzero::AndroidLogPacket_LogEvent** out_evt); 114 115 base::TaskRunner* const task_runner_; 116 std::unique_ptr<TraceWriter> writer_; 117 base::UnixSocketRaw logdr_sock_; 118 119 // Config parameters coming from the data source section in the trace config. 120 int min_prio_ = 0; 121 std::string mode_; 122 123 // For filtering events based on tags. 124 std::unordered_set<base::StringView> filter_tags_; 125 std::vector<char> filter_tags_strbuf_; 126 127 // Lookup map for binary events (log_id=EVENTS). Translates a numeric id into 128 // a corresponding field descriptor. This is generated by parsing 129 // /system/etc/event-log-tags when starting. 130 std::unordered_map<int, EventFormat> event_formats_; 131 132 // Buffer used for parsing. It's safer (read: fails sooner) than using the 133 // stack, due to red zones around the boundaries. 134 base::PagedMemory buf_; 135 Stats stats_; 136 bool fd_watch_task_enabled_ = false; 137 138 base::WeakPtrFactory<AndroidLogDataSource> weak_factory_; // Keep last. 139 }; 140 141 } // namespace perfetto 142 143 #endif // SRC_TRACED_PROBES_ANDROID_LOG_ANDROID_LOG_DATA_SOURCE_H_ 144