1/*
2 * Copyright (C) 2011 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 *
30 */
31
32#include "config.h"
33#include "core/loader/LinkLoader.h"
34
35#include "FetchInitiatorTypeNames.h"
36#include "core/dom/Document.h"
37#include "core/fetch/FetchRequest.h"
38#include "core/fetch/ResourceFetcher.h"
39#include "core/html/LinkRelAttribute.h"
40#include "core/loader/PrerenderHandle.h"
41#include "core/frame/Settings.h"
42#include "platform/network/DNS.h"
43
44namespace WebCore {
45
46LinkLoader::LinkLoader(LinkLoaderClient* client)
47    : m_client(client)
48    , m_linkLoadTimer(this, &LinkLoader::linkLoadTimerFired)
49    , m_linkLoadingErrorTimer(this, &LinkLoader::linkLoadingErrorTimerFired)
50{
51}
52
53LinkLoader::~LinkLoader()
54{
55}
56
57void LinkLoader::linkLoadTimerFired(Timer<LinkLoader>* timer)
58{
59    ASSERT_UNUSED(timer, timer == &m_linkLoadTimer);
60    m_client->linkLoaded();
61}
62
63void LinkLoader::linkLoadingErrorTimerFired(Timer<LinkLoader>* timer)
64{
65    ASSERT_UNUSED(timer, timer == &m_linkLoadingErrorTimer);
66    m_client->linkLoadingErrored();
67}
68
69void LinkLoader::notifyFinished(Resource* resource)
70{
71    ASSERT(this->resource() == resource);
72
73    if (resource->errorOccurred())
74        m_linkLoadingErrorTimer.startOneShot(0);
75    else
76        m_linkLoadTimer.startOneShot(0);
77
78    clearResource();
79}
80
81void LinkLoader::didStartPrerender()
82{
83    m_client->didStartLinkPrerender();
84}
85
86void LinkLoader::didStopPrerender()
87{
88    m_client->didStopLinkPrerender();
89}
90
91void LinkLoader::didSendLoadForPrerender()
92{
93    m_client->didSendLoadForLinkPrerender();
94}
95
96void LinkLoader::didSendDOMContentLoadedForPrerender()
97{
98    m_client->didSendDOMContentLoadedForLinkPrerender();
99}
100
101bool LinkLoader::loadLink(const LinkRelAttribute& relAttribute, const String& type, const KURL& href, Document& document)
102{
103    if (relAttribute.isDNSPrefetch()) {
104        Settings* settings = document.settings();
105        // FIXME: The href attribute of the link element can be in "//hostname" form, and we shouldn't attempt
106        // to complete that as URL <https://bugs.webkit.org/show_bug.cgi?id=48857>.
107        if (settings && settings->dnsPrefetchingEnabled() && href.isValid() && !href.isEmpty())
108            prefetchDNS(href.host());
109    }
110
111    // FIXME(crbug.com/323096): Should take care of import.
112    if ((relAttribute.isLinkPrefetch() || relAttribute.isLinkSubresource()) && href.isValid() && document.frame()) {
113        if (!m_client->shouldLoadLink())
114            return false;
115        Resource::Type type = relAttribute.isLinkSubresource() ?  Resource::LinkSubresource : Resource::LinkPrefetch;
116        FetchRequest linkRequest(ResourceRequest(document.completeURL(href)), FetchInitiatorTypeNames::link);
117        setResource(document.fetcher()->fetchLinkResource(type, linkRequest));
118    }
119
120    if (relAttribute.isLinkPrerender()) {
121        if (!m_prerender) {
122            m_prerender = PrerenderHandle::create(document, this, href);
123        } else if (m_prerender->url() != href) {
124            m_prerender->cancel();
125            m_prerender = PrerenderHandle::create(document, this, href);
126        }
127    } else if (m_prerender) {
128        m_prerender->cancel();
129        m_prerender.clear();
130    }
131    return true;
132}
133
134void LinkLoader::released()
135{
136    // Only prerenders need treatment here; other links either use the Resource interface, or are notionally
137    // atomic (dns prefetch).
138    if (m_prerender) {
139        m_prerender->cancel();
140        m_prerender.clear();
141    }
142}
143
144}
145