pv/view/rowitemiterator.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_ROWITEMITERATOR_HPP
  22 #define PULSEVIEW_PV_VIEW_ROWITEMITERATOR_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 #ifdef _WIN32
  33 // Windows: Avoid namespace pollution by thread.hpp (which includes windows.h).
  34 #define NOGDI
  35 #define NORESOURCE
  36 #endif
  37 #include <boost/thread/locks.hpp>
  38 #include <boost/thread/shared_mutex.hpp>
  39
  40 #include <pv/session.hpp>
  41
  42 namespace pv {
  43 namespace view {
  44
  45 template<class Owner, class Item> class RowItemIterator
  46 {
  47 public:
  48         typedef typename std::conditional<std::is_const<Owner>::value,
  49                 typename Owner::item_list::const_iterator,
  50                 typename Owner::item_list::iterator>::type child_iterator;
  51
  52         typedef std::shared_ptr<Item> value_type;
  53         typedef ptrdiff_t difference_type;
  54         typedef value_type pointer;
  55         typedef value_type& reference;
  56         typedef std::forward_iterator_tag iterator_category;
  57
  58 public:
  59         RowItemIterator(Owner *owner) :
  60                 owner_(owner),
  61                 lock_(owner->session().signals_mutex()) {}
  62
  63         RowItemIterator(Owner *owner, child_iterator iter) :
  64                 owner_(owner),
  65                 lock_(owner->session().signals_mutex()) {
  66                 assert(owner);
  67                 if (iter != owner->child_items().end())
  68                         iter_stack_.push(iter);
  69         }
  70
  71         RowItemIterator(const RowItemIterator<Owner, Item> &o) :
  72                 owner_(o.owner_),
  73                 lock_(*o.lock_.mutex()),
  74                 iter_stack_(o.iter_stack_) {}
  75
  76         reference operator*() const {
  77                 return *iter_stack_.top();
  78         }
  79
  80         reference operator->() const {
  81                 return *this;
  82         }
  83
  84         RowItemIterator<Owner, Item>& operator++() {
  85                 using std::dynamic_pointer_cast;
  86                 using std::shared_ptr;
  87
  88                 assert(owner_);
  89                 assert(!iter_stack_.empty());
  90
  91                 shared_ptr<Owner> owner(dynamic_pointer_cast<Owner>(
  92                         *iter_stack_.top()));
  93                 if (owner && !owner->child_items().empty()) {
  94                         owner_ = owner.get();
  95                         iter_stack_.push(owner->child_items().begin());
  96                 } else {
  97                         ++iter_stack_.top();
  98                         while (owner_ && iter_stack_.top() ==
  99                                 owner_->child_items().end()) {
 100                                 iter_stack_.pop();
 101                                 owner_ = iter_stack_.empty() ? nullptr :
 102                                         (*iter_stack_.top()++)->owner();
 103                         }
 104                 }
 105
 106                 return *this;
 107         }
 108
 109         RowItemIterator<Owner, Item> operator++(int) {
 110                 RowItemIterator<Owner, Item> pre = *this;
 111                 ++*this;
 112                 return pre;
 113         }
 114
 115         bool operator==(const RowItemIterator &o) const {
 116                 return (iter_stack_.empty() && o.iter_stack_.empty()) ||
 117                         (owner_ == o.owner_ &&
 118                         iter_stack_.size() == o.iter_stack_.size() &&
 119                         std::equal(
 120                                 owner_->child_items().cbegin(),
 121                                 owner_->child_items().cend(),
 122                                 o.owner_->child_items().cbegin()));
 123         }
 124
 125         bool operator!=(const RowItemIterator &o) const {
 126                 return !((const RowItemIterator&)*this == o);
 127         }
 128
 129         void swap(RowItemIterator<Owner, Item>& other) {
 130                 swap(owner_, other.owner_);
 131                 swap(iter_stack_, other.iter_stack_);
 132         }
 133
 134 private:
 135         Owner *owner_;
 136         boost::shared_lock<boost::shared_mutex> lock_;
 137         std::stack<child_iterator> iter_stack_;
 138 };
 139
 140 template<class Owner, class Item>
 141 void swap(RowItemIterator<Owner, Item>& a, RowItemIterator<Owner, Item>& b)
 142 {
 143         a.swap(b);
 144 }
 145
 146 } // namespace view
 147 } // namespace pv
 148
 149 #endif // PULSEVIEW_PV_VIEW_ROWITEMITERATOR_HPP