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1273.1.30
by Jay Pipes
* Completes the blueprint for splitting the XA Resource Manager |
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/* -*- mode: c++; c-basic-offset: 2; indent-tabs-mode: nil; -*-
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* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
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*
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* Copyright (c) 2010 Jay Pipes <jaypipes@gmail.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; version 2 of the License.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef DRIZZLED_PLUGIN_MONITORED_IN_TRANSACTION_H
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#define DRIZZLED_PLUGIN_MONITORED_IN_TRANSACTION_H
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#include <cstring> |
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namespace drizzled |
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{
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namespace plugin |
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{
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extern size_t num_trx_monitored_objects; |
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/**
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* An abstract interface class for those objects which are tracked
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* by the TransactionServices component during operations in a
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* transaction.
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*
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* Note that both non-transactional plugin::StorageEngines, non-XA
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* plugin::TransactionalStorageEngines, and plugin::XaResourceManager
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* objects are all tracked by the transaction manager in TransactionServices.
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*
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* Implementing classes should inherit *publically* from
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* plugin::MonitoredInTransaction, as public inheritance means
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* "is a" and is the appropriate use here since all implementing classes
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* *are* monitored in a transaction...
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*/
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class MonitoredInTransaction |
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{
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public: |
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MonitoredInTransaction(); |
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virtual ~MonitoredInTransaction() {} |
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/**
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* Returns true if the class should participate
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* in the SQL transaction.
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*/
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virtual bool participatesInSqlTransaction() const= 0; |
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/**
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* Returns true if the class should participate
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* in the XA transaction.
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*/
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virtual bool participatesInXaTransaction() const= 0; |
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/**
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* Returns true if the class should be registered
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* for every XA transaction regardless of whether
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* the class modifies the server's state.
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*
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* @note
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*
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* As an example, the XaTransactionApplier plugin class returns
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* true for this virtual method. Even though it does not
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* change the result of the transaction (it simply is logging
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* the changes made by other resource managers), the applier
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* plugin should be enlisted in all XA transactions in order
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* to be able to rollback or recover its logging activity
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* properly.
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*/
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virtual bool alwaysRegisterForXaTransaction() const= 0; |
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/**
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* Returns the "slot" or ID of the monitored resource
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*/
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size_t getId() const |
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{
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return id; |
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}
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private: |
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/**
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* The ID or "slot" of the plugin.
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*
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* @todo
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*
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* Maybe move this into plugin::Plugin? Only issue then is
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* that all plugins would have a ha_data slot, when only a few
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* actually need that. Maybe create a plugin::NeedsSessionData?
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*/
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size_t id; |
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};
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} /* namespace plugin */ |
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} /* namespace drizzled */ |
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#endif /* DRIZZLED_PLUGIN_MONITORED_IN_TRANSACTION_H */ |