libcruft-util/pool.ipp

97 lines
2.4 KiB
Plaintext
Raw Normal View History

2012-08-22 16:12:26 +10:00
/*
* This file is part of libgim.
*
* libgim 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 3 of the License, or (at your option) any later
* version.
*
* libgim 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 libgim. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright 2011-2012 Danny Robson <danny@nerdcruft.net>
*/
#ifdef __UTIL_POOL_IPP
#error Double inclusion of pool.ipp
#endif
#define __UTIL_POOL_IPP
namespace util {
template <typename T>
pool<T>::pool (unsigned int _capacity):
m_capacity (_capacity)
{
static_assert (sizeof (T) >= sizeof (uintptr_t),
"pool<T>'s chained block system requires that T be at least pointer sized");
2014-05-20 13:44:49 +10:00
m_head = static_cast<node *> (operator new (sizeof (T) * m_capacity));
2012-08-22 16:12:26 +10:00
m_next = m_head;
for (unsigned int i = 0; i < m_capacity - 1; ++i)
m_next[i]._chain = &m_next[i + 1];
m_next[m_capacity - 1]._chain = NULL;
}
template <typename T>
pool<T>::~pool () {
CHECK (m_next != NULL);
unsigned int doomed_count = 0;
for (node *cursor = m_next; cursor != NULL; cursor = cursor->_chain)
++doomed_count;
CHECK_EQ (doomed_count, m_capacity);
operator delete (m_head);
}
2014-05-20 13:44:27 +10:00
2012-08-22 16:12:26 +10:00
template <typename T>
unsigned int
pool<T>::capacity (void) const
{ return m_capacity; }
template <typename T>
template <typename ...Args>
T*
pool<T>::acquire (Args&... args) {
if (!m_next)
throw std::bad_alloc ();
node *newnext = m_next->_chain;
T *data = (T*)&m_next->_data;
2014-05-20 13:44:27 +10:00
2012-08-22 16:12:26 +10:00
try {
new (data) T (args...);
} catch (...) {
m_next->_chain = newnext;
throw;
}
m_next = newnext;
return data;
}
template <typename T>
void
pool<T>::release (T *data) {
data->~T();
2014-05-20 13:44:49 +10:00
node *newnode = reinterpret_cast<node *> (data);
2012-08-22 16:12:26 +10:00
newnode->_chain = m_next;
m_next = newnode;
}
}