/* GRAPHITE2 LICENSING Copyright 2011, SIL International All rights reserved. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of License, or (at your option) any later version. 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 Lesser General Public License for more details. You should also have received a copy of the GNU Lesser General Public License along with this library in the file named "LICENSE". If not, write to the Free Software Foundation, 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA or visit their web page on the internet at http://www.fsf.org/licenses/lgpl.html. Alternatively, the contents of this file may be used under the terms of the Mozilla Public License (http://mozilla.org/MPL) or the GNU General Public License, as published by the Free Software Foundation, either version 2 of the License or (at your option) any later version. */ #pragma once #include #include #include "inc/Main.h" namespace graphite2 { // A read-only packed fast sparse array of uint16 with uint16 keys. // Like most container classes this has capacity and size properties and these // refer to the number of stored entries and the number of addressable entries // as normal. However due the sparse nature the capacity is always <= than the // size. class sparse { public: typedef uint16 key_type; typedef uint16 mapped_type; typedef std::pair value_type; private: typedef unsigned long mask_t; static const unsigned char SIZEOF_CHUNK = (sizeof(mask_t) - sizeof(key_type))*8; struct chunk { mask_t mask:SIZEOF_CHUNK; key_type offset; }; static chunk empty_chunk; sparse(const sparse &); sparse & operator = (const sparse &); public: template sparse(I first, const I last); sparse() throw(); ~sparse() throw(); operator bool () const throw(); mapped_type operator [] (const key_type k) const throw(); size_t capacity() const throw(); size_t size() const throw(); size_t _sizeof() const throw(); CLASS_NEW_DELETE; private: union { chunk * map; mapped_type * values; } m_array; key_type m_nchunks; }; inline sparse::sparse() throw() : m_nchunks(0) { m_array.map = &empty_chunk; } template sparse::sparse(I attr, const I last) : m_nchunks(0) { m_array.map = 0; // Find the maximum extent of the key space. size_t n_values=0; long lastkey = -1; for (I i = attr; i != last; ++i, ++n_values) { const typename std::iterator_traits::value_type v = *i; if (v.second == 0) { --n_values; continue; } if (v.first <= lastkey) { m_nchunks = 0; return; } lastkey = v.first; const key_type k = v.first / SIZEOF_CHUNK; if (k >= m_nchunks) m_nchunks = k+1; } if (m_nchunks == 0) { m_array.map=&empty_chunk; return; } m_array.values = grzeroalloc((m_nchunks*sizeof(chunk) + sizeof(mapped_type)-1) / sizeof(mapped_type) + n_values); if (m_array.values == 0) { free(m_array.values); m_array.map=0; return; } chunk * ci = m_array.map; ci->offset = (m_nchunks*sizeof(chunk) + sizeof(mapped_type)-1)/sizeof(mapped_type); mapped_type * vi = m_array.values + ci->offset; for (; attr != last; ++attr, ++vi) { const typename std::iterator_traits::value_type v = *attr; if (v.second == 0) { --vi; continue; } chunk * const ci_ = m_array.map + v.first/SIZEOF_CHUNK; if (ci != ci_) { ci = ci_; ci->offset = vi - m_array.values; } ci->mask |= 1UL << (SIZEOF_CHUNK - 1 - (v.first % SIZEOF_CHUNK)); *vi = v.second; } } inline sparse::operator bool () const throw() { return m_array.map != 0; } inline size_t sparse::size() const throw() { return m_nchunks*SIZEOF_CHUNK; } inline size_t sparse::_sizeof() const throw() { return sizeof(sparse) + capacity()*sizeof(mapped_type) + m_nchunks*sizeof(chunk); } } // namespace graphite2