1 //---------------------------------------------------------------------------//
2 // Copyright (c) 2014 Roshan <thisisroshansmail@gmail.com>
4 // Distributed under the Boost Software License, Version 1.0
5 // See accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt
8 // See http://boostorg.github.com/compute for more information.
9 //---------------------------------------------------------------------------//
11 #ifndef BOOST_COMPUTE_ALGORITHM_SEARCH_HPP
12 #define BOOST_COMPUTE_ALGORITHM_SEARCH_HPP
14 #include <boost/compute/algorithm/detail/search_all.hpp>
15 #include <boost/compute/algorithm/find.hpp>
16 #include <boost/compute/container/vector.hpp>
17 #include <boost/compute/detail/iterator_range_size.hpp>
18 #include <boost/compute/detail/meta_kernel.hpp>
19 #include <boost/compute/system.hpp>
25 /// \brief Substring matching algorithm
27 /// Searches for the first match of the pattern [p_first, p_last)
28 /// in text [t_first, t_last).
29 /// \return Iterator pointing to beginning of first occurrence
31 /// \param t_first Iterator pointing to start of text
32 /// \param t_last Iterator pointing to end of text
33 /// \param p_first Iterator pointing to start of pattern
34 /// \param p_last Iterator pointing to end of pattern
35 /// \param queue Queue on which to execute
37 template<class TextIterator, class PatternIterator>
38 inline TextIterator search(TextIterator t_first,
40 PatternIterator p_first,
41 PatternIterator p_last,
42 command_queue &queue = system::default_queue())
44 // there is no need to check if pattern starts at last n - 1 indices
45 vector<uint_> matching_indices(
46 detail::iterator_range_size(t_first, t_last)
47 - detail::iterator_range_size(p_first, p_last) + 1,
51 // search_kernel puts value 1 at every index in vector where pattern starts at
52 detail::search_kernel<PatternIterator,
54 vector<uint_>::iterator> kernel;
56 kernel.set_range(p_first, p_last, t_first, t_last, matching_indices.begin());
59 vector<uint_>::iterator index = ::boost::compute::find(
60 matching_indices.begin(), matching_indices.end(), uint_(1), queue
63 // pattern was not found
64 if(index == matching_indices.end())
67 return t_first + detail::iterator_range_size(matching_indices.begin(), index);
70 } //end compute namespace
71 } //end boost namespace
73 #endif // BOOST_COMPUTE_ALGORITHM_SEARCH_HPP