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// libTorrent - BitTorrent library
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// Copyright (C) 2005-2007, Jari Sundell
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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; either version 2 of the License, or
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// (at your option) any later version.
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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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// 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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// In addition, as a special exception, the copyright holders give
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// permission to link the code of portions of this program with the
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// OpenSSL library under certain conditions as described in each
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// individual source file, and distribute linked combinations
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// You must obey the GNU General Public License in all respects for
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// all of the code used other than OpenSSL. If you modify file(s)
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// with this exception, you may extend this exception to your version
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// of the file(s), but you are not obligated to do so. If you do not
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// wish to do so, delete this exception statement from your version.
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// If you delete this exception statement from all source files in the
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// program, then also delete it here.
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// Contact: Jari Sundell <jaris@ifi.uio.no>
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// 3185 Skoppum, NORWAY
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#ifndef LIBTORRENT_BITFIELD_H
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#define LIBTORRENT_BITFIELD_H
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#include <torrent/common.h>
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class LIBTORRENT_EXPORT Bitfield {
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typedef uint32_t size_type;
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typedef uint8_t value_type;
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typedef const uint8_t const_value_type;
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typedef value_type* iterator;
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typedef const value_type* const_iterator;
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Bitfield() : m_size(0), m_set(0), m_data(NULL) {}
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~Bitfield() { clear(); }
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bool empty() const { return m_data == NULL; }
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bool is_all_set() const { return m_set == m_size; }
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bool is_all_unset() const { return m_set == 0; }
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bool is_tail_cleared() const { return m_size % 8 == 0 || !((*(end() - 1) & mask_from(m_size % 8))); }
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size_type size_bits() const { return m_size; }
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size_type size_bytes() const { return (m_size + 7) / 8; }
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size_type size_set() const { return m_set; }
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size_type size_unset() const { return m_size - m_set; }
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void set_size_bits(size_type s);
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void set_size_set(size_type s);
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// Call update if you've changed the data directly and want to
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// update the counters and unset the last unused bits.
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// Resize clears the data?
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void allocate() { if (m_data == NULL) m_data = new value_type[size_bytes()]; }
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void unallocate() { delete [] m_data; m_data = NULL; }
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void clear() { unallocate(); m_size = 0; m_set = 0; }
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void clear_tail() { if (m_size % 8) *(end() - 1) &= mask_before(m_size % 8); }
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void copy(const Bitfield& bf);
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void swap(Bitfield& bf);
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void set_range(size_type first, size_type last);
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void unset_range(size_type first, size_type last);
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bool get(size_type idx) const { return m_data[idx / 8] & mask_at(idx % 8); }
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void set(size_type idx) { m_set += !get(idx); m_data[idx / 8] |= mask_at(idx % 8); }
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void unset(size_type idx) { m_set -= get(idx); m_data[idx / 8] &= ~mask_at(idx % 8); }
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iterator begin() { return m_data; }
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const_iterator begin() const { return m_data; }
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iterator end() { return m_data + size_bytes(); }
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const_iterator end() const { return m_data + size_bytes(); }
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size_type position(const_iterator itr) const { return (itr - m_data) * 8; }
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void from_c_str(const char* str) { std::memcpy(m_data, str, size_bytes()); update(); }
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// Remember to use modulo.
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static value_type mask_at(size_type idx) { return 1 << (7 - idx); }
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static value_type mask_before(size_type idx) { return (value_type)~0 << (8 - idx); }
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static value_type mask_from(size_type idx) { return (value_type)~0 >> idx; }
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Bitfield(const Bitfield& bf);
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Bitfield& operator = (const Bitfield& bf);
added
removed
src/torrent/bitfield.h
