polardbxengine/plugin/x/client/xpriority_list.h

87 lines
2.5 KiB
C++

/*
* Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, version 2.0,
* as published by the Free Software Foundation.
*
* This program is also distributed with certain software (including
* but not limited to OpenSSL) that is licensed under separate terms,
* as designated in a particular file or component or in included license
* documentation. The authors of MySQL hereby grant you an additional
* permission to link the program and your derivative works with the
* separately licensed software that they have included with MySQL.
*
* 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, version 2.0, 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
*/
// MySQL DB access module, for use by plugins and others
// For the module that implements interactive DB functionality see mod_db
#ifndef PLUGIN_X_CLIENT_XPRIORITY_LIST_H_
#define PLUGIN_X_CLIENT_XPRIORITY_LIST_H_
#include <algorithm>
#include <list>
namespace xcl {
template <typename Element_type,
bool (*Priority_compare)(const Element_type &, const Element_type &) =
Element_type::compare>
class Priority_list {
public:
using Iterator = typename std::list<Element_type>::iterator;
public:
void push_front(const Element_type &n) {
const auto i = std::find_if(
m_list.begin(), m_list.end(),
[&n](const Element_type &e) { return !Priority_compare(e, n); });
if (m_list.end() == i) {
m_list.push_back(n);
return;
}
m_list.insert(i, n);
}
void push_back(const Element_type &n) {
const auto i = std::find_if(
m_list.rbegin(), m_list.rend(),
[&n](const Element_type &e) { return !Priority_compare(n, e); });
if (m_list.rend() == i) {
m_list.push_front(n);
return;
}
m_list.insert(i.base(), n);
}
void erase(Iterator i) { m_list.erase(i); }
void clear() { m_list.clear(); }
Iterator begin() { return m_list.begin(); }
Iterator end() { return m_list.end(); }
private:
std::list<Element_type> m_list;
};
} // namespace xcl
#endif // PLUGIN_X_CLIENT_XPRIORITY_LIST_H_