table_id.h

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/**
  @file table_id.h
 
  @brief Contains the class Table_id, mainly used for row based replication.
*/
 
#ifndef MYSQL_BINLOG_EVENT_TABLE_ID_H
#define MYSQL_BINLOG_EVENT_TABLE_ID_H
#include <stdint.h>
#include "mysql/binlog/event/wrapper_functions.h"
 
namespace mysql::binlog::event {
 
/**
  @class Table_id
 
  @brief Each table share has a table id, it is mainly used for row based
  replication. Meanwhile it is used as table's version too.
*/
class Table_id {
 private:
  /* In table map event and rows events, table id is 6 bytes.*/
  static const unsigned long long TABLE_ID_MAX = (~0ULL >> 16);
  uint64_t m_id;
 
 public:
  Table_id() : m_id(0) {}
  explicit Table_id(unsigned long long id) : m_id(id) {}
 
  unsigned long long id() const { return m_id; }
  bool is_valid() const { return m_id <= TABLE_ID_MAX; }
 
  Table_id &operator=(unsigned long long id) {
    m_id = id;
    return *this;
  }
 
  bool operator==(const Table_id &tid) const { return m_id == tid.m_id; }
  bool operator!=(const Table_id &tid) const { return m_id != tid.m_id; }
 
  /* Support implicit type converting from Table_id to unsigned long long */
  operator unsigned long long() const { return m_id; }
 
  Table_id operator++(int) {
    Table_id id(m_id);
 
    /* m_id is reset to 0, when it exceeds the max value. */
    m_id = (m_id == TABLE_ID_MAX ? 0 : m_id + 1);
 
    BAPI_ASSERT(m_id <= TABLE_ID_MAX);
    return id;
  }
};
 
}  // namespace mysql::binlog::event
 
#endif  // MYSQL_BINLOG_EVENT_TABLE_ID_H