/* -*- c++ -*- */ /* * Copyright (C) 2009 The Android Open Source Project * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef ANDROID_ASTL_ALGORITHM__ #define ANDROID_ASTL_ALGORITHM__ #include <cstddef> #include <cstring> #include <type_traits.h> #ifndef ANDROID_ASTL_TYPE_TRAITS_H__ #error "Wrong file included!" #endif namespace std { // This file contains the following template functions: // - min // - max // - swap // - fill // - fill_n // - equal template<typename _T> inline const _T& min(const _T& left, const _T& right) { if (left < right) return left; return right; } template<typename _T> inline const _T& max(const _T& left, const _T& right) { if (right < left) return left; return right; } template<typename _T> inline void swap(_T& left, _T& right) { _T tmp = left; left = right; right = tmp; } // fill the range [begin, end) with copies of value, return nothing. // fill_n the range [begin, begin + n) with copies of value, return // the pointer at begin + n. // // TODO: fill and fill_n should take forward and output iterators for // begin and end params. Fix this when iterator are defined. template<bool> struct __fill { template<typename _T> static void fill(_T *begin, const _T *end, const _T& value) { for (; begin < end; ++begin) *begin = value; } }; template<> struct __fill<true> // scalar version { template<typename _T> static void fill(_T *begin, const _T *end, const _T& value) { const _T tmp = value; for (; begin < end; ++begin) *begin = tmp; } }; template<typename _T> void fill(_T *begin, _T *end, const _T& value) { const bool is_scalar = std::is_scalar<_T>::value; __fill<is_scalar>::fill(begin, end, value); } // Specialization: for one-byte types use memset. inline void fill(unsigned char *begin, unsigned char *end, const unsigned char& value) { if (begin < end) { const int tmp = value; std::memset(begin, tmp, end - begin); } } inline void fill(signed char *begin, signed char *end, const signed char& value) { if (begin < end) { const int tmp = value; std::memset(begin, tmp, end - begin); } } inline void fill(char *begin, char *end, const char& value) { if (begin < end) { const int tmp = value; std::memset(begin, tmp, end - begin); } } template<bool> struct __fill_n { template<typename _T> static _T *fill_n(_T *begin, size_t num, const _T& value) { for (size_t i = 0; i < num; ++i, ++begin) { *begin = value; } return begin; } }; template<> struct __fill_n<true> // scalar version { template<typename _T> static _T *fill_n(_T *begin, size_t num, const _T& value) { const _T tmp = value; for (size_t i = 0; i < num; ++i, ++begin) { *begin = tmp; } return begin; } }; template<typename _T> _T *fill_n(_T *begin, size_t n, const _T& value) { const bool is_scalar = std::is_scalar<_T>::value; return __fill_n<is_scalar>::fill_n(begin, n, value); } // Specialization: for one-byte types uses memset. inline unsigned char *fill_n(unsigned char *begin, size_t num, const unsigned char& value) { const int tmp = value; std::memset(begin, tmp, num); return begin + num; } inline signed char *fill_n(signed char *begin, size_t num, const signed char& value) { const int tmp = value; std::memset(begin, tmp, num); return begin + num; } inline char *fill_n(char *begin, size_t num, const char& value) { const int tmp = value; std::memset(begin, tmp, num); return begin + num; } // Test a range for element-wise equality using operator== // @param begin1 An input iterator. // @param end1 An input iterator. // @param begin2 An input iterator. // @return true if all the elements of the range are equal. // TODO: When we have a proper structure for iterator as opposed to // just pointers, we should be able to the get the type for the values // referenced by the iterator and default to memcmp for simple types. // TODO: equal should degrade to memcmp for pod. template<typename _InputIterator1, typename _InputIterator2> inline bool equal(_InputIterator1 begin1, _InputIterator1 end1, _InputIterator2 begin2) { for (; begin1 < end1; ++begin1, ++begin2) { if (!(*begin1 == *begin2)) { return false; } } return true; } // Test a range for element-wise equality using operator== // @param begin1 An input iterator. // @param end1 An input iterator. // @param begin2 An input iterator. // @param binary_pred A binary predicate function. // @return true if all the elements of the range are equal. template<typename _InputIterator1, typename _InputIterator2, typename _BinaryPredicated> inline bool equal(_InputIterator1 begin1, _InputIterator1 end1, _InputIterator2 begin2, _BinaryPredicated binary_predicate) { for (; begin1 < end1; ++begin1, ++begin2) { if (!bool(binary_predicate(*begin1, *begin2))) { return false; } } return true; } } // namespace std #endif