1// Bitmap Allocator. Out of line function definitions. -*- C++ -*-
2
3// Copyright (C) 2004-2022 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.
10
11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14// GNU General Public License for more details.
15
16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.
19
20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23// <http://www.gnu.org/licenses/>.
24
25#include <ext/bitmap_allocator.h>
26
27namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
28{
29_GLIBCXX_BEGIN_NAMESPACE_VERSION
30
31  using std::size_t;
32
33  namespace __detail
34  {
35    template class __mini_vector<
36      std::pair<bitmap_allocator<char>::_Alloc_block*,
37		bitmap_allocator<char>::_Alloc_block*> >;
38
39    template class __mini_vector<
40      std::pair<bitmap_allocator<wchar_t>::_Alloc_block*,
41		bitmap_allocator<wchar_t>::_Alloc_block*> >;
42
43    template class __mini_vector<size_t*>;
44
45    template size_t** __lower_bound(size_t**, size_t**, size_t const&,
46				    free_list::_LT_pointer_compare);
47  }
48
49  size_t*
50  free_list::
51  _M_get(size_t __sz) throw(std::bad_alloc)
52  {
53#if defined __GTHREADS
54    __mutex_type& __bfl_mutex = _M_get_mutex();
55    __bfl_mutex.lock();
56#endif
57    const vector_type& __free_list = _M_get_free_list();
58    using __gnu_cxx::__detail::__lower_bound;
59    iterator __tmp = __lower_bound(__free_list.begin(), __free_list.end(),
60				   __sz, _LT_pointer_compare());
61
62    if (__tmp == __free_list.end() || !_M_should_i_give(**__tmp, __sz))
63      {
64	// We release the lock here, because operator new is
65	// guaranteed to be thread-safe by the underlying
66	// implementation.
67#if defined __GTHREADS
68	__bfl_mutex.unlock();
69#endif
70	// Try twice to get the memory: once directly, and the 2nd
71	// time after clearing the free list. If both fail, then throw
72	// std::bad_alloc().
73	int __ctr = 2;
74	while (__ctr)
75	  {
76	    size_t* __ret = 0;
77	    --__ctr;
78	    __try
79	      {
80		__ret = reinterpret_cast<size_t*>
81		  (::operator new(__sz + sizeof(size_t)));
82	      }
83	    __catch(const std::bad_alloc&)
84	      {
85		this->_M_clear();
86	      }
87	    if (!__ret)
88	      continue;
89	    *__ret = __sz;
90	    return __ret + 1;
91	  }
92	std::__throw_bad_alloc();
93      }
94    else
95      {
96	size_t* __ret = *__tmp;
97	_M_get_free_list().erase(__tmp);
98#if defined __GTHREADS
99	__bfl_mutex.unlock();
100#endif
101	return __ret + 1;
102      }
103  }
104
105  void
106  free_list::
107  _M_clear()
108  {
109#if defined __GTHREADS
110    __gnu_cxx::__scoped_lock __bfl_lock(_M_get_mutex());
111#endif
112    vector_type& __free_list = _M_get_free_list();
113    iterator __iter = __free_list.begin();
114    while (__iter != __free_list.end())
115      {
116	::operator delete((void*)*__iter);
117	++__iter;
118      }
119    __free_list.clear();
120  }
121
122  // Instantiations.
123  template class bitmap_allocator<char>;
124  template class bitmap_allocator<wchar_t>;
125
126_GLIBCXX_END_NAMESPACE_VERSION
127} // namespace
128