pv/view/viewitemiterator.hpp

   1 /*
   2  * This file is part of the PulseView project.
   3  *
   4  * Copyright (C) 2014 Joel Holdsworth <joel@airwebreathe.org.uk>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  */
  20
  21 #ifndef PULSEVIEW_PV_VIEW_VIEWITEMITERATOR_HPP
  22 #define PULSEVIEW_PV_VIEW_VIEWITEMITERATOR_HPP
  23
  24 #include <algorithm>
  25 #include <cassert>
  26 #include <iterator>
  27 #include <memory>
  28 #include <stack>
  29 #include <type_traits>
  30 #include <vector>
  31
  32 #include <pv/session.hpp>
  33
  34 namespace pv {
  35 namespace view {
  36
  37 template<class Owner, class Item> class ViewItemIterator
  38 {
  39 public:
  40         typedef typename std::conditional<std::is_const<Owner>::value,
  41                 typename Owner::item_list::const_iterator,
  42                 typename Owner::item_list::iterator>::type child_iterator;
  43
  44         typedef std::shared_ptr<Item> value_type;
  45         typedef ptrdiff_t difference_type;
  46         typedef value_type pointer;
  47         typedef value_type& reference;
  48         typedef std::forward_iterator_tag iterator_category;
  49
  50 public:
  51         ViewItemIterator(Owner *owner) :
  52                 owner_stack_({owner}) {}
  53
  54         ViewItemIterator(Owner *owner, child_iterator iter) :
  55                 owner_stack_({owner}) {
  56                 assert(owner);
  57                 if (iter != owner->child_items().end())
  58                         iter_stack_.push(iter);
  59         }
  60
  61         ViewItemIterator(const ViewItemIterator<Owner, Item> &o) :
  62                 owner_stack_(o.owner_stack_),
  63                 iter_stack_(o.iter_stack_) {}
  64
  65         reference operator*() const {
  66                 return *iter_stack_.top();
  67         }
  68
  69         reference operator->() const {
  70                 return *this;
  71         }
  72
  73         ViewItemIterator<Owner, Item>& operator++() {
  74                 using std::dynamic_pointer_cast;
  75                 using std::shared_ptr;
  76
  77                 assert(!owner_stack_.empty());
  78                 assert(!iter_stack_.empty());
  79
  80                 shared_ptr<Owner> owner(dynamic_pointer_cast<Owner>(
  81                         *iter_stack_.top()));
  82                 if (owner && !owner->child_items().empty()) {
  83                         owner_stack_.push(owner.get());
  84                         iter_stack_.push(owner->child_items().begin());
  85                 } else {
  86                         while (!iter_stack_.empty() && (++iter_stack_.top()) ==
  87                                 owner_stack_.top()->child_items().end()) {
  88                                 owner_stack_.pop();
  89                                 iter_stack_.pop();
  90                         }
  91                 }
  92
  93                 return *this;
  94         }
  95
  96         ViewItemIterator<Owner, Item> operator++(int) {
  97                 ViewItemIterator<Owner, Item> pre = *this;
  98                 ++*this;
  99                 return pre;
 100         }
 101
 102         bool operator==(const ViewItemIterator &o) const {
 103                 return (iter_stack_.empty() && o.iter_stack_.empty()) || (
 104                         iter_stack_.size() == o.iter_stack_.size() &&
 105                         owner_stack_.top() == o.owner_stack_.top() &&
 106                         iter_stack_.top() == o.iter_stack_.top());
 107         }
 108
 109         bool operator!=(const ViewItemIterator &o) const {
 110                 return !((const ViewItemIterator&)*this == o);
 111         }
 112
 113         void swap(ViewItemIterator<Owner, Item>& other) {
 114                 swap(owner_stack_, other.owner_stack_);
 115                 swap(iter_stack_, other.iter_stack_);
 116         }
 117
 118 private:
 119         std::stack<Owner*> owner_stack_;
 120         std::stack<child_iterator> iter_stack_;
 121 };
 122
 123 template<class Owner, class Item>
 124 void swap(ViewItemIterator<Owner, Item>& a, ViewItemIterator<Owner, Item>& b)
 125 {
 126         a.swap(b);
 127 }
 128
 129 } // namespace view
 130 } // namespace pv
 131
 132 #endif // PULSEVIEW_PV_VIEW_VIEWITEMITERATOR_HPP