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1796.4.1
by Andrew Hutchings
Add initial template work and test |
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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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1796.4.20
by Andrew Hutchings
Fix copyright |
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* Copyright (C) 2010 Andrew Hutchings
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1796.4.1
by Andrew Hutchings
Add initial template work and test |
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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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1796.4.18
by Andrew Hutchings
Fix lint errors |
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#ifndef DRIZZLED_GLOBAL_BUFFER_H
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#define DRIZZLED_GLOBAL_BUFFER_H
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1796.4.1
by Andrew Hutchings
Add initial template work and test |
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#include <drizzled/atomics.h> |
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namespace drizzled |
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{
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template <class T> |
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class global_buffer_constraint |
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{
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public: |
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1796.4.8
by Andrew Hutchings
Change default setting |
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global_buffer_constraint(T max) |
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{
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setMaxSize(max); |
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}
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1796.4.1
by Andrew Hutchings
Add initial template work and test |
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T getMaxSize() const { return max_size; } |
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1796.4.8
by Andrew Hutchings
Change default setting |
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void setMaxSize(T new_size) |
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{
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if (new_size == 0) new_size = std::numeric_limits<T>::max(); |
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max_size= new_size; |
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}
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1796.4.1
by Andrew Hutchings
Add initial template work and test |
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bool add(T addition) |
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{
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if (current_size.add_and_fetch(addition) > max_size) |
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{
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current_size.add_and_fetch(T(0) - addition); |
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return false; |
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}
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return true; |
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}
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bool sub(T subtract) |
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{
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if (current_size < subtract) |
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return false; |
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else
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current_size.add_and_fetch(T(0) - subtract); |
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return true; |
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}
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private: |
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atomic<T> current_size; |
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T max_size; |
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};
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}
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1796.4.18
by Andrew Hutchings
Fix lint errors |
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#endif /* DRIZZLED_GLOBAL_BUFFER_H */ |