~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; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  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/plugin/catalog.h>

#include <drizzled/catalog/cache.h>

#include <drizzled/catalog/local.h>

#include <drizzled/error.h>

#include <boost/foreach.hpp>

namespace drizzled

{

namespace plugin

{

// Private container we use for holding the instances of engines passed to

// use from the catalog plugins.

class Engines {

  catalog::Engine::vector _catalogs;

public:

  static Engines& singleton()

  {

    static Engines ptr;

    return ptr;

  }

  catalog::Engine::vector &catalogs()

  {

    return _catalogs;

  }

};

bool Catalog::create(const identifier::Catalog& identifier)

{

  message::catalog::shared_ptr message= message::catalog::make_shared(identifier);

  return create(identifier, message);

}

bool Catalog::create(const identifier::Catalog& identifier, message::catalog::shared_ptr &message)

{

  assert(message);

  catalog::lock::Create lock(identifier);

  if (not lock.locked())

  {

    my_error(ER_CATALOG_NO_LOCK, MYF(0), identifier.getName().c_str());

    return false;

  }

  size_t create_count= 0;

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    if (ref->create(identifier, message))

      create_count++;

  }

  assert(create_count < 2);

  if (not create_count)

  {

    my_error(ER_CATALOG_CANNOT_CREATE, MYF(0), identifier.getName().c_str());

    return false;

  }

  return true;

}

bool Catalog::drop(const identifier::Catalog& identifier)

{

  if (identifier == drizzled::catalog::local_identifier())

  {

    my_error(drizzled::ER_CATALOG_NO_DROP_LOCAL, MYF(0));

    return false;

  }

  catalog::lock::Erase lock(identifier);

  if (not lock.locked())

  {

    my_error(ER_CATALOG_NO_LOCK, MYF(0), identifier.getName().c_str());

    return false; 

  }

  size_t drop_count= 0;

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    if (ref->drop(identifier))

      drop_count++;

  }

  assert(drop_count < 2);

  if (not drop_count)

  {

    my_error(ER_CATALOG_DOES_NOT_EXIST, MYF(0), identifier.getName().c_str());

    return false;

  }

  return true;

}

bool Catalog::lock(const identifier::Catalog& identifier)

{

  drizzled::error_t error;

  // We insert a lock into the cache, if this fails we bail.

  if (not catalog::Cache::lock(identifier, error))

  {

    my_error(error, identifier);

    return false;

  }

  return true;

}

bool Catalog::unlock(const identifier::Catalog& identifier)

{

  drizzled::error_t error;

  if (not catalog::Cache::unlock(identifier, error))

  {

    my_error(error, identifier);

  }

  return false;

}

bool plugin::Catalog::addPlugin(plugin::Catalog *arg)

{

  Engines::singleton().catalogs().push_back(arg->engine());

  return false;

}

bool plugin::Catalog::exist(const identifier::Catalog& identifier)

{

  if (catalog::Cache::exist(identifier))

    return true;

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    if (ref->exist(identifier))

      return true;

  }

  return false;

}

void plugin::Catalog::getIdentifiers(identifier::catalog::vector &identifiers)

{

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    ref->getIdentifiers(identifiers);

  }

}

void plugin::Catalog::getMessages(message::catalog::vector &messages)

{

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    ref->getMessages(messages);

  }

}

message::catalog::shared_ptr plugin::Catalog::getMessage(const identifier::Catalog& identifier)

{

  drizzled::error_t error;

  catalog::Instance::shared_ptr instance= catalog::Cache::find(identifier, error);

  message::catalog::shared_ptr message;

  if (instance and instance->message())

  {

    return instance->message();

  }

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    if ((message= ref->getMessage(identifier)))

      return message;

  }

  return message;

}

catalog::Instance::shared_ptr plugin::Catalog::getInstance(const identifier::Catalog& identifier)

{

  drizzled::error_t error;

  catalog::Instance::shared_ptr instance= catalog::Cache::find(identifier, error);

  if (instance)

    return instance;

  BOOST_FOREACH(catalog::Engine::vector::const_reference ref, Engines::singleton().catalogs())

  {

    message::catalog::shared_ptr message;

    if (message= ref->getMessage(identifier))

    {

      instance= catalog::Instance::make_shared(message);

      // If this should fail inserting into the cache, we are in a world of

      // pain.

      catalog::Cache::insert(identifier, instance, error);

      return instance;

    }

  }

  return catalog::Instance::shared_ptr();

}

void plugin::Catalog::removePlugin(plugin::Catalog *)

{

}

} /* namespace plugin */

} /* namespace drizzled */