src/trace_processor/trace_processor.h

/*
 * Copyright (C) 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SRC_TRACE_PROCESSOR_TRACE_PROCESSOR_H_
#define SRC_TRACE_PROCESSOR_TRACE_PROCESSOR_H_

#include <atomic>
#include <functional>
#include <memory>

#include "perfetto/base/weak_ptr.h"
#include "src/trace_processor/scoped_db.h"
#include "src/trace_processor/trace_processor_context.h"

namespace perfetto {

namespace base {
class TaskRunner;
}

namespace protos {
class RawQueryArgs;
class RawQueryResult;
}  // namespace protos

namespace trace_processor {

class BlobReader;

// Coordinates the loading of traces from an arbitary source and allows
// execution of SQL queries on the events in these traces.
class TraceProcessor {
 public:
  explicit TraceProcessor(base::TaskRunner*);
  ~TraceProcessor();

  // Loads a trace by reading from the given blob reader. Invokes |callback|
  // when the trace has been fully read and parsed.
  void LoadTrace(BlobReader*, std::function<void()> callback);

  // Executes a SQLite query on the loaded portion of the trace. |result| will
  // be invoked once after the result of the query is available.
  void ExecuteQuery(const protos::RawQueryArgs&,
                    std::function<void(const protos::RawQueryResult&)>);

  // Interrupts the current query. Typically used by Ctrl-C handler.
  void InterruptQuery();

 private:
  void LoadTraceChunk(std::function<void()> callback);

  ScopedDb db_;  // Keep first.
  TraceProcessorContext context_;
  base::TaskRunner* const task_runner_;

  // This is atomic because it is set by the CTRL-C signal handler and we need
  // to prevent single-flow compiler optimizations in ExecuteQuery().
  std::atomic<bool> query_interrupted_{false};

  base::WeakPtrFactory<TraceProcessor> weak_factory_;  // Keep last.
};

// When set, logs SQLite actions on the console.
void EnableSQLiteVtableDebugging();

}  // namespace trace_processor
}  // namespace perfetto

#endif  // SRC_TRACE_PROCESSOR_TRACE_PROCESSOR_H_