prefetched_ifile.h

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#ifndef MYSQL_CSA_STORAGE_RELAY_LOG_PREFETCHED_IFILE_H
#define MYSQL_CSA_STORAGE_RELAY_LOG_PREFETCHED_IFILE_H
 
#include <atomic>
#include <cstring>
#include <memory>
#include <vector>
 
#include "sql/basic_istream.h"   // Basic_istream
#include "sql/binlog_istream.h"  // Basic_binlog_ifile
#include "sql/binlog_reader.h"
#include "sql/changestreams/apply/storage/relay_log/istream_prefetched.h"
#include "sql/log_event.h"  // Log_event
 
namespace mysql::csa {
 
/// Implementation of the Basic_binlog_ifile, which works on the
/// prefetched stream (Istream_prefetched)
/// Exposes additional function to set prefetcher (since legacy design does
/// not allow to use a custom constructor - see Basic_binlog_file_reader).
class Prefetched_ifile : public Basic_binlog_ifile {
 public:
  using Basic_binlog_ifile::Basic_binlog_ifile;
 
  /// Sets the prefetcher. Prefetcher must be set before opening the first file.
  /// Later on, same prefetcher object is reused to initialize
  /// Istream_prefetched object, which uses asynchronous prefetcher to get
  /// data.
  /// @param prefetcher Shared prefetcher object.
  void set_prefetcher(Log_prefetcher_sptr prefetcher);
 
 protected:
  /// Creates stream object "from the file". Data will be obtained
  /// via prefetcher
  std::unique_ptr<Basic_seekable_istream> open_file(
      const char *file_name) override;
 
  /// File currently opened
  std::string m_current_file;
  /// Prefetcher object we need to pass into created stream
  Log_prefetcher_sptr m_prefetcher;
};
 
}  // namespace mysql::csa
 
#endif  // MYSQL_CSA_STORAGE_RELAY_LOG_PREFETCHED_IFILE_H