// Copyright (c) 2001, Daniel C. Nuffer | |
// Copyright (c) 2001-2011 Hartmut Kaiser | |
// | |
// Distributed under the Boost Software License, Version 1.0. (See accompanying | |
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) | |
#if !defined(BOOST_SPIRIT_ITERATOR_BUF_ID_CHECK_POLICY_MAR_16_2007_1108AM) | |
#define BOOST_SPIRIT_ITERATOR_BUF_ID_CHECK_POLICY_MAR_16_2007_1108AM | |
#include <boost/spirit/home/support/iterators/multi_pass_fwd.hpp> | |
#include <boost/spirit/home/support/iterators/detail/multi_pass.hpp> | |
#include <boost/config.hpp> | |
#include <boost/throw_exception.hpp> | |
#include <exception> // for std::exception | |
namespace boost { namespace spirit { namespace iterator_policies | |
{ | |
/////////////////////////////////////////////////////////////////////////// | |
// class illegal_backtracking | |
// thrown by buf_id_check CheckingPolicy if an instance of an iterator is | |
// used after another one has invalidated the queue | |
/////////////////////////////////////////////////////////////////////////// | |
class illegal_backtracking : public std::exception | |
{ | |
public: | |
illegal_backtracking() throw() {} | |
~illegal_backtracking() throw() {} | |
char const* what() const throw() | |
{ | |
return "boost::spirit::multi_pass::illegal_backtracking"; | |
} | |
}; | |
/////////////////////////////////////////////////////////////////////////////// | |
// class buf_id_check | |
// Implementation of the CheckingPolicy used by multi_pass | |
// This policy is most effective when used together with the std_deque | |
// StoragePolicy. | |
// | |
// If used with the fixed_size_queue StoragePolicy, it will not detect | |
// iterator dereferences that are out of the range of the queue. | |
/////////////////////////////////////////////////////////////////////////////// | |
struct buf_id_check | |
{ | |
/////////////////////////////////////////////////////////////////////// | |
struct unique //: detail::default_checking_policy | |
{ | |
unique() : buf_id(0) {} | |
unique(unique const& x) : buf_id(x.buf_id) {} | |
void swap(unique& x) | |
{ | |
boost::swap(buf_id, x.buf_id); | |
} | |
// called to verify that everything is ok. | |
template <typename MultiPass> | |
static void docheck(MultiPass const& mp) | |
{ | |
if (mp.buf_id != mp.shared()->shared_buf_id) | |
boost::throw_exception(illegal_backtracking()); | |
} | |
// called from multi_pass::clear_queue, so we can increment the count | |
template <typename MultiPass> | |
static void clear_queue(MultiPass& mp) | |
{ | |
++mp.shared()->shared_buf_id; | |
++mp.buf_id; | |
} | |
template <typename MultiPass> | |
static void destroy(MultiPass&) {} | |
protected: | |
unsigned long buf_id; | |
}; | |
/////////////////////////////////////////////////////////////////////// | |
struct shared | |
{ | |
shared() : shared_buf_id(0) {} | |
unsigned long shared_buf_id; | |
}; | |
}; | |
}}} | |
#endif |