src/trace_processor/sqlite/stats_table.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_SQLITE_STATS_TABLE_H_
#define SRC_TRACE_PROCESSOR_SQLITE_STATS_TABLE_H_

#include <limits>
#include <memory>

#include "src/trace_processor/sqlite/sqlite_table.h"
#include "src/trace_processor/storage/stats.h"
#include "src/trace_processor/storage/trace_storage.h"

namespace perfetto {
namespace trace_processor {

// The stats table contains diagnostic info and errors that are either:
// - Collected at trace time (e.g., ftrace buffer overruns).
// - Generated at parsing time (e.g., clock events out-of-order).
class StatsTable : public SqliteTable {
 public:
  enum Column { kName = 0, kIndex, kSeverity, kSource, kValue };
  class Cursor : public SqliteTable::Cursor {
   public:
    Cursor(StatsTable*);

    // Implementation of SqliteTable::Cursor.
    int Filter(const QueryConstraints&,
               sqlite3_value**,
               FilterHistory) override;
    int Next() override;
    int Eof() override;
    int Column(sqlite3_context*, int N) override;

   private:
    Cursor(Cursor&) = delete;
    Cursor& operator=(const Cursor&) = delete;

    Cursor(Cursor&&) noexcept = default;
    Cursor& operator=(Cursor&&) = default;

    StatsTable* table_ = nullptr;
    const TraceStorage* storage_ = nullptr;
    size_t key_ = 0;
    TraceStorage::Stats::IndexMap::const_iterator index_{};
  };

  static void RegisterTable(sqlite3* db, const TraceStorage* storage);

  StatsTable(sqlite3*, const TraceStorage*);

  // Table implementation.
  util::Status Init(int, const char* const*, SqliteTable::Schema*) override;
  std::unique_ptr<SqliteTable::Cursor> CreateCursor() override;
  int BestIndex(const QueryConstraints&, BestIndexInfo*) override;

 private:
  const TraceStorage* const storage_;
};
}  // namespace trace_processor
}  // namespace perfetto

#endif  // SRC_TRACE_PROCESSOR_SQLITE_STATS_TABLE_H_