2 * Copyright (C) 2010 Apple Inc. All rights reserved.
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
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18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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23 * THE POSSIBILITY OF SUCH DAMAGE.
27 #include "WebBackForwardList.h"
29 #include "WebPageProxy.h"
33 static const unsigned DefaultCapacity = 100;
35 WebBackForwardList::WebBackForwardList(WebPageProxy* page)
37 , m_hasCurrentIndex(false)
39 , m_capacity(DefaultCapacity)
44 WebBackForwardList::~WebBackForwardList()
46 // A WebBackForwardList should never be destroyed unless it's associated page has been closed or is invalid.
47 ASSERT((!m_page && !m_hasCurrentIndex) || !m_page->isValid());
50 void WebBackForwardList::pageClosed()
52 // We should have always started out with an m_page and we should never close the page twice.
56 size_t size = m_entries.size();
57 for (size_t i = 0; i < size; ++i) {
61 m_page->backForwardRemovedItem(m_entries[i]->itemID());
67 m_hasCurrentIndex = false;
70 void WebBackForwardList::addItem(WebBackForwardListItem* newItem)
72 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
74 if (!m_capacity || !newItem || !m_page)
77 Vector<RefPtr<APIObject> > removedItems;
79 if (m_hasCurrentIndex) {
80 // Toss everything in the forward list.
81 unsigned targetSize = m_currentIndex + 1;
82 removedItems.reserveCapacity(m_entries.size() - targetSize);
83 while (m_entries.size() > targetSize) {
84 m_page->backForwardRemovedItem(m_entries.last()->itemID());
85 removedItems.append(m_entries.last().release());
86 m_entries.removeLast();
89 // Toss the first item if the list is getting too big, as long as we're not using it
90 // (or even if we are, if we only want 1 entry).
91 if (m_entries.size() == m_capacity && (m_currentIndex || m_capacity == 1)) {
92 m_page->backForwardRemovedItem(m_entries[0]->itemID());
93 removedItems.append(m_entries[0].release());
96 if (m_entries.isEmpty())
97 m_hasCurrentIndex = false;
102 // If we have no current item index we should also not have any entries.
103 ASSERT(m_entries.isEmpty());
105 // But just in case it does happen in practice we'll get back in to a consistent state now before adding the new item.
106 size_t size = m_entries.size();
107 for (size_t i = 0; i < size; ++i) {
108 ASSERT(m_entries[i]);
111 m_page->backForwardRemovedItem(m_entries[i]->itemID());
112 removedItems.append(m_entries[i].release());
117 if (!m_hasCurrentIndex) {
118 ASSERT(m_entries.isEmpty());
120 m_hasCurrentIndex = true;
124 // m_current never be pointing more than 1 past the end of the entries Vector.
125 // If it is, something has gone wrong and we should not try to insert the new item.
126 ASSERT(m_currentIndex <= m_entries.size());
127 if (m_currentIndex <= m_entries.size())
128 m_entries.insert(m_currentIndex, newItem);
130 m_page->didChangeBackForwardList(newItem, &removedItems);
133 void WebBackForwardList::goToItem(WebBackForwardListItem* item)
135 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
137 if (!m_entries.size() || !item || !m_page || !m_hasCurrentIndex)
141 for (; index < m_entries.size(); ++index) {
142 if (m_entries[index] == item)
145 if (index < m_entries.size()) {
146 m_currentIndex = index;
147 m_page->didChangeBackForwardList(0, 0);
151 WebBackForwardListItem* WebBackForwardList::currentItem()
153 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
155 return m_page && m_hasCurrentIndex ? m_entries[m_currentIndex].get() : 0;
158 WebBackForwardListItem* WebBackForwardList::backItem()
160 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
162 return m_page && m_hasCurrentIndex && m_currentIndex ? m_entries[m_currentIndex - 1].get() : 0;
165 WebBackForwardListItem* WebBackForwardList::forwardItem()
167 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
169 return m_page && m_hasCurrentIndex && m_entries.size() && m_currentIndex < m_entries.size() - 1 ? m_entries[m_currentIndex + 1].get() : 0;
172 WebBackForwardListItem* WebBackForwardList::itemAtIndex(int index)
174 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
176 if (!m_hasCurrentIndex || !m_page)
179 // Do range checks without doing math on index to avoid overflow.
180 if (index < -backListCount())
183 if (index > forwardListCount())
186 return m_entries[index + m_currentIndex].get();
189 int WebBackForwardList::backListCount()
191 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
193 return m_page && m_hasCurrentIndex ? m_currentIndex : 0;
196 int WebBackForwardList::forwardListCount()
198 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
200 return m_page && m_hasCurrentIndex ? m_entries.size() - (m_currentIndex + 1) : 0;
203 PassRefPtr<ImmutableArray> WebBackForwardList::backListAsImmutableArrayWithLimit(unsigned limit)
205 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
207 if (!m_page || !m_hasCurrentIndex)
208 return ImmutableArray::create();
210 unsigned backListSize = static_cast<unsigned>(backListCount());
211 unsigned size = std::min(backListSize, limit);
213 return ImmutableArray::create();
215 Vector<RefPtr<APIObject> > vector;
216 vector.reserveInitialCapacity(size);
218 ASSERT(backListSize >= size);
219 for (unsigned i = backListSize - size; i < backListSize; ++i) {
220 ASSERT(m_entries[i]);
221 vector.uncheckedAppend(m_entries[i].get());
224 return ImmutableArray::adopt(vector);
227 PassRefPtr<ImmutableArray> WebBackForwardList::forwardListAsImmutableArrayWithLimit(unsigned limit)
229 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
231 if (!m_page || !m_hasCurrentIndex)
232 return ImmutableArray::create();
234 unsigned size = std::min(static_cast<unsigned>(forwardListCount()), limit);
236 return ImmutableArray::create();
238 Vector<RefPtr<APIObject> > vector;
239 vector.reserveInitialCapacity(size);
241 unsigned last = m_currentIndex + size;
242 ASSERT(last < m_entries.size());
243 for (unsigned i = m_currentIndex + 1; i <= last; ++i) {
244 ASSERT(m_entries[i]);
245 vector.uncheckedAppend(m_entries[i].get());
248 return ImmutableArray::adopt(vector);
251 void WebBackForwardList::clear()
253 ASSERT(!m_hasCurrentIndex || m_currentIndex < m_entries.size());
255 size_t size = m_entries.size();
256 if (!m_page || size <= 1)
259 RefPtr<WebBackForwardListItem> currentItem = this->currentItem();
260 Vector<RefPtr<APIObject> > removedItems;
263 // We should only ever have no current item if we also have no current item index.
264 ASSERT(!m_hasCurrentIndex);
266 // But just in case it does happen in practice we should get back into a consistent state now.
267 for (size_t i = 0; i < size; ++i) {
268 ASSERT(m_entries[i]);
272 m_page->backForwardRemovedItem(m_entries[i]->itemID());
273 removedItems.append(m_entries[i].release());
277 m_hasCurrentIndex = false;
278 m_page->didChangeBackForwardList(0, &removedItems);
283 for (size_t i = 0; i < size; ++i) {
284 ASSERT(m_entries[i]);
285 if (m_entries[i] && m_entries[i] != currentItem)
286 m_page->backForwardRemovedItem(m_entries[i]->itemID());
289 removedItems.reserveCapacity(size - 1);
290 for (size_t i = 0; i < size; ++i) {
291 if (i != m_currentIndex && m_hasCurrentIndex && m_entries[i])
292 removedItems.append(m_entries[i].release());
299 m_entries[0] = currentItem.release();
302 m_hasCurrentIndex = false;
305 m_page->didChangeBackForwardList(0, &removedItems);
308 } // namespace WebKit