~drizzle-trunk/drizzle/development

/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2010 Brian Aker

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; version 2 of the License.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#include "config.h"

#include "drizzled/session.h"

#include "drizzled/global_charset_info.h"

#include "drizzled/charset.h"

#include "drizzled/transaction_services.h"

#include "drizzled/plugin/storage_engine.h"

#include "drizzled/plugin/authorization.h"

namespace drizzled

{

namespace plugin

{

class AddSchemaNames : 

  public std::unary_function<StorageEngine *, void>

{

  SchemaIdentifier::vector &schemas;

public:

  AddSchemaNames(SchemaIdentifier::vector &of_names) :

    schemas(of_names)

  {

  }

  result_type operator() (argument_type engine)

  {

    engine->doGetSchemaIdentifiers(schemas);

  }

};

void StorageEngine::getIdentifiers(Session &session, SchemaIdentifier::vector &schemas)

{

  // Add hook here for engines to register schema.

  std::for_each(StorageEngine::getSchemaEngines().begin(), StorageEngine::getSchemaEngines().end(),

           AddSchemaNames(schemas));

  plugin::Authorization::pruneSchemaNames(session.user(), schemas);

}

class StorageEngineGetSchemaDefinition: public std::unary_function<StorageEngine *, bool>

{

  const SchemaIdentifier &identifier;

  message::schema::shared_ptr &schema_proto;

public:

  StorageEngineGetSchemaDefinition(const SchemaIdentifier &identifier_arg,

                                   message::schema::shared_ptr &schema_proto_arg) :

    identifier(identifier_arg),

    schema_proto(schema_proto_arg) 

  {

  }

  result_type operator() (argument_type engine)

  {

    return engine->doGetSchemaDefinition(identifier, schema_proto);

  }

};

/*

  Return value is "if parsed"

*/

bool StorageEngine::getSchemaDefinition(const drizzled::TableIdentifier &identifier, message::schema::shared_ptr &proto)

{

  return StorageEngine::getSchemaDefinition(identifier, proto);

}

bool StorageEngine::getSchemaDefinition(const SchemaIdentifier &identifier, message::schema::shared_ptr &proto)

{

  EngineVector::iterator iter=

    std::find_if(StorageEngine::getSchemaEngines().begin(), StorageEngine::getSchemaEngines().end(),

                 StorageEngineGetSchemaDefinition(identifier, proto));

  if (iter != StorageEngine::getSchemaEngines().end())

  {

    return true;

  }

  return false;

}

bool StorageEngine::doesSchemaExist(const SchemaIdentifier &identifier)

{

  message::schema::shared_ptr proto;

  return StorageEngine::getSchemaDefinition(identifier, proto);

}

const CHARSET_INFO *StorageEngine::getSchemaCollation(const SchemaIdentifier &identifier)

{

  message::schema::shared_ptr schmema_proto;

  bool found;

  found= StorageEngine::getSchemaDefinition(identifier, schmema_proto);

  if (found && schmema_proto->has_collation())

  {

    const std::string buffer= schmema_proto->collation();

    const CHARSET_INFO* cs= get_charset_by_name(buffer.c_str());

    if (not cs)

    {

      std::string path;

      identifier.getSQLPath(path);

      errmsg_printf(ERRMSG_LVL_ERROR,

                    _("Error while loading database options: '%s':"), path.c_str());

      errmsg_printf(ERRMSG_LVL_ERROR, ER(ER_UNKNOWN_COLLATION), buffer.c_str());

      return default_charset_info;

    }

    return cs;

  }

  return default_charset_info;

}

class CreateSchema : 

  public std::unary_function<StorageEngine *, void>

{

  const drizzled::message::Schema &schema_message;

public:

  CreateSchema(const drizzled::message::Schema &arg) :

    schema_message(arg)

  {

  }

  result_type operator() (argument_type engine)

  {

    // @todo eomeday check that at least one engine said "true"

    bool success= engine->doCreateSchema(schema_message);

    if (success) 

    {

      TransactionServices &transaction_services= TransactionServices::singleton();

      transaction_services.allocateNewTransactionId();

    }

  }

};

bool StorageEngine::createSchema(const drizzled::message::Schema &schema_message)

{

  // Add hook here for engines to register schema.

  std::for_each(StorageEngine::getSchemaEngines().begin(), StorageEngine::getSchemaEngines().end(),

                CreateSchema(schema_message));

  return true;

}

class DropSchema : 

  public std::unary_function<StorageEngine *, void>

{

  uint64_t &success_count;

  const SchemaIdentifier &identifier;

public:

  DropSchema(const SchemaIdentifier &arg, uint64_t &count_arg) :

    success_count(count_arg),

    identifier(arg)

  {

  }

  result_type operator() (argument_type engine)

  {

    // @todo someday check that at least one engine said "true"

    bool success= engine->doDropSchema(identifier);

    if (success)

    {

      success_count++;

      TransactionServices &transaction_services= TransactionServices::singleton();

      transaction_services.allocateNewTransactionId();

    }

  }

};

static bool drop_all_tables_in_schema(Session& session,

                                      SchemaIdentifier::const_reference identifier,

                                      TableIdentifier::vector &dropped_tables,

                                      uint64_t &deleted)

{

  TransactionServices &transaction_services= TransactionServices::singleton();

  plugin::StorageEngine::getIdentifiers(session, identifier, dropped_tables);

  for (TableIdentifier::vector::iterator it= dropped_tables.begin();

       it != dropped_tables.end();

       it++)

  {

    boost::mutex::scoped_lock scopedLock(table::Cache::singleton().mutex());

    table::Cache::singleton().removeTable(&session, *it,

                                          RTFC_WAIT_OTHER_THREAD_FLAG |

                                          RTFC_CHECK_KILLED_FLAG);

    if (plugin::StorageEngine::dropTable(session, *it))

    {

      my_error(ER_TABLE_DROP, *it);

      return false;

    }

    transaction_services.dropTable(&session, *it, true);

    deleted++;

  }

  return true;

}

bool StorageEngine::dropSchema(Session::reference session, SchemaIdentifier::const_reference identifier)

{

  uint64_t deleted= 0;

  bool error= false;

  TableIdentifier::vector dropped_tables;

  message::Schema schema_proto;

  do

  {

    // Remove all temp tables first, this prevents loss of table from

    // shadowing (ie temp over standard table)

    {

      // Lets delete the temporary tables first outside of locks.  

      TableIdentifier::vector set_of_identifiers;

      session.doGetTableIdentifiers(identifier, set_of_identifiers);

      for (TableIdentifier::vector::iterator iter= set_of_identifiers.begin(); iter != set_of_identifiers.end(); iter++)

      {

        if (session.drop_temporary_table(*iter))

        {

          my_error(ER_TABLE_DROP, *iter);

          error= true;

          break;

        }

      }

    }

    /* After deleting database, remove all cache entries related to schema */

    table::Cache::singleton().removeSchema(identifier);

    if (not drop_all_tables_in_schema(session, identifier, dropped_tables, deleted))

    {

      error= true;

      my_error(ER_DROP_SCHEMA, identifier);

      break;

    }

    uint64_t counter= 0;

    // Add hook here for engines to register schema.

    std::for_each(StorageEngine::getSchemaEngines().begin(), StorageEngine::getSchemaEngines().end(),

                  DropSchema(identifier, counter));

    if (not counter)

    {

      my_error(ER_DROP_SCHEMA, identifier);

      error= true;

      break;

    }

    else

    {

      /* We've already verified that the schema does exist, so safe to log it */

      TransactionServices &transaction_services= TransactionServices::singleton();

      transaction_services.dropSchema(&session, identifier);

    }

  } while (0);

  if (deleted > 0)

  {

    session.clear_error();

    session.server_status|= SERVER_STATUS_DB_DROPPED;

    session.my_ok((uint32_t) deleted);

    session.server_status&= ~SERVER_STATUS_DB_DROPPED;

  }

  return error;

}

class AlterSchema : 

  public std::unary_function<StorageEngine *, void>

{

  uint64_t &success_count;

  const drizzled::message::Schema &schema_message;

public:

  AlterSchema(const drizzled::message::Schema &arg, uint64_t &count_arg) :

    success_count(count_arg),

    schema_message(arg)

  {

  }

  result_type operator() (argument_type engine)

  {

    // @todo eomeday check that at least one engine said "true"

    bool success= engine->doAlterSchema(schema_message);

    if (success)

    {

      success_count++;

      TransactionServices &transaction_services= TransactionServices::singleton();

      transaction_services.allocateNewTransactionId();

    }

  }

};

bool StorageEngine::alterSchema(const drizzled::message::Schema &schema_message)

{

  uint64_t success_count= 0;

  std::for_each(StorageEngine::getSchemaEngines().begin(), StorageEngine::getSchemaEngines().end(),

                AlterSchema(schema_message, success_count));

  return success_count ? true : false;

}

} /* namespace plugin */

} /* namespace drizzled */