sdi_api.h

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   it under the terms of the GNU General Public License, version 2.0,
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
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   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#ifndef DD_SDI_API_INCLUDED
#define DD_SDI_API_INCLUDED

#include <memory>

#include "sql/dd/string_type.h"
#include "sql/dd/types/table.h"

struct MEM_ROOT;
class MDL_request;
class THD;
class Table_ref;

namespace dd {
namespace sdi {

/**
  State and operations for importing an sdi file into the DD.
 */
class Import_target {
  /** Full path to the sdi file being imported. */
  dd::String_type m_path;

  /** True if path points inside data dir */
  bool m_in_datadir;

  /** Temporary name for sdi files in data dir when import is ongoing */
  dd::String_type m_tmp_sdi_filename;

  /** Table object which the sdi will be deserialized into */
  std::unique_ptr<dd::Table> m_table_object;

  /** Schema name found in sdi */
  dd::String_type m_schema_name_in_sdi;

  /**
    Lower-case representation of table name if
    lower_case_table_names==2, nullptr otherwise.
  */
  std::unique_ptr<dd::String_type> m_lc_tname;

  /**
    Lower-case representation of schema name if
    lower_case_table_names==2, nullptr otherwise.
  */
  std::unique_ptr<dd::String_type> m_lc_sname;

 public:
  /**
    Creates an instance to handle the import of a single sdi file.
    @param path full path to an sdi file to import
    @param in_datadir true if the file is located somewhere under the
           server's data directory.
   */
  Import_target(String_type &&path, bool in_datadir);

  /**
    Having a unique_ptr as member makes this a move-only type.
   */
  Import_target(Import_target &&) = default;
  Import_target(const Import_target &) = delete;

  /**
    Finish import by removing tmp sdi file when importing from sdi
    file in datadir.

    @retval true if an error occurred
    @retval false otherwise
   */
  bool commit() const;

  /**
    Restore old state by renaming tmp sdi file back to its original
    name when importing from sdi file in datadir.

    @retval true if an error occurred
    @retval false otherwise
   */
  bool rollback() const;

  /**
    Obtains the canonical table name for use with MDL and
    privilege-checking. For lower_case_table_names=0 and 1, this is
    the same as the name of the Table object. For
    lower_case_table_names=2 it is the lower case version of the
    tablename.

    @returns pointer to dd::String_type holding canonical name
   */
  const dd::String_type *can_table_name() const;

  /**
    Obtains the canonical schema name for use with MDL and
    privilege-checking. For lower_case_table_names=0 and 1, this is
    the same as the schema name of the table in the sdi. For
    lower_case_table_names=2 it is the lower case version of the
    schemaname.

    @returns pointer to dd::String_type holding canonical name
   */
  const dd::String_type *can_schema_name() const;

  /**
    Reads the sdi file from disk and dserializes it into a Table
    object and its schema name, but does not store Table object in the
    DD.

    @param thd thread context
    @param shared_buffer pointer to a dd::String_type which is used to
           store the sdi string until it is deserialized.
    @retval true if an error occurred
    @retval false otherwise
   */
  bool load(THD *thd, String_type *shared_buffer);

  /**
    Constructs a Table_ref object with info from this Import_target.
    Table_ref::db and Table_ref::table_name are initialized to the
    canonical (lowercased for lctn==2) representation,
    Table_ref::alias to the native
    table_name, and Table_ref::m_lock_descriptor.type is set to
    TL_IGNORE.
   */
  Table_ref make_table_ref() const;

  /**
    Update the schema reference in the Table object and store
    it in the DD so that it becomes visible. Precondition: The
    Import_target must be loaded and privileges checked before this
    member function is called.

    @param thd thread handle
    @retval true if an error occurred
    @retval false otherwise
   */
  bool store_in_dd(THD *thd) const;
};

/**
  Check that we have the the necessary privileges to import this
  table.  Precondition: The Import_target must be loaded before this
  member function is called.

  @param thd thread handle
  @param t import target context
  @retval true if an error occurred
  @retval false otherwise
*/
bool check_privileges(THD *thd, const Import_target &t);

/**
  Creates an MDL_request for exclusive MDL on the table being
  imported. Does not actually lock the name, that must be done later
  for all requests to avoid deadlock.

  @param t import target context
  @param mem_root where to allocate the MDL_request
  @return pointer to mem_root allocated MDL_request
*/
MDL_request *mdl_request(const Import_target &t, MEM_ROOT *mem_root);

/**
  Drop all SDIs from all tablespaces associated with table. For a partitioned
  table SDIs are deleted from all the partition tablespaces.
*/
bool drop_all_for_table(THD *, const Table *);

/**
  Drop all SDIs from all tablespaces associated with partition or
  sub-partition. For a top-level partition of a sub-partitioned table, SDIs are
  removed for all sub-partitions of that partition.
*/
bool drop_all_for_part(THD *, const Partition *);
}  // namespace sdi
}  // namespace dd

#endif /* DD_SDI_API_INCLUDED */