summaryrefslogtreecommitdiffstats
path: root/dom/base/Link.cpp
blob: e0cd4ed71d3c4bdf07cf0844ce2d70295d48df7c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "Link.h"

#include "mozilla/EventStates.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/dom/Element.h"
#include "nsIURL.h"
#include "nsISizeOf.h"
#include "nsIDocShell.h"
#include "nsIPrefetchService.h"
#include "nsCPrefetchService.h"
#include "nsStyleLinkElement.h"

#include "nsEscape.h"
#include "nsGkAtoms.h"
#include "nsHTMLDNSPrefetch.h"
#include "nsString.h"
#include "mozAutoDocUpdate.h"

#include "mozilla/Services.h"

namespace mozilla {
namespace dom {

Link::Link(Element *aElement)
  : mElement(aElement)
  , mHistory(services::GetHistoryService())
  , mLinkState(eLinkState_NotLink)
  , mNeedsRegistration(false)
  , mRegistered(false)
{
  MOZ_ASSERT(mElement, "Must have an element");
}

Link::~Link()
{
  UnregisterFromHistory();
}

bool
Link::ElementHasHref() const
{
  return mElement->HasAttr(kNameSpaceID_None, nsGkAtoms::href) ||
         (!mElement->IsHTMLElement() &&
          mElement->HasAttr(kNameSpaceID_XLink, nsGkAtoms::href));
}

void
Link::TryDNSPrefetch()
{
  MOZ_ASSERT(mElement->IsInComposedDoc());
  if (ElementHasHref() && nsHTMLDNSPrefetch::IsAllowed(mElement->OwnerDoc())) {
    nsHTMLDNSPrefetch::PrefetchLow(this);
  }
}

void
Link::CancelDNSPrefetch(nsWrapperCache::FlagsType aDeferredFlag,
                        nsWrapperCache::FlagsType aRequestedFlag)
{
  // If prefetch was deferred, clear flag and move on
  if (mElement->HasFlag(aDeferredFlag)) {
    mElement->UnsetFlags(aDeferredFlag);
    // Else if prefetch was requested, clear flag and send cancellation
  } else if (mElement->HasFlag(aRequestedFlag)) {
    mElement->UnsetFlags(aRequestedFlag);
    // Possible that hostname could have changed since binding, but since this
    // covers common cases, most DNS prefetch requests will be canceled
    nsHTMLDNSPrefetch::CancelPrefetchLow(this, NS_ERROR_ABORT);
  }
}

void
Link::TryDNSPrefetchPreconnectOrPrefetch()
{
  MOZ_ASSERT(mElement->IsInComposedDoc());
  if (!ElementHasHref()) {
    return;
  }

  nsAutoString rel;
  if (!mElement->GetAttr(kNameSpaceID_None, nsGkAtoms::rel, rel)) {
    return;
  }

  if (!nsContentUtils::PrefetchEnabled(mElement->OwnerDoc()->GetDocShell())) {
    return;
  }

  uint32_t linkTypes = nsStyleLinkElement::ParseLinkTypes(rel,
                         mElement->NodePrincipal());

  if ((linkTypes & nsStyleLinkElement::ePREFETCH) ||
      (linkTypes & nsStyleLinkElement::eNEXT)){
    nsCOMPtr<nsIPrefetchService> prefetchService(do_GetService(NS_PREFETCHSERVICE_CONTRACTID));
    if (prefetchService) {
      nsCOMPtr<nsIURI> uri(GetURI());
      if (uri) {
        nsCOMPtr<nsIDOMNode> domNode = GetAsDOMNode(mElement);
        prefetchService->PrefetchURI(uri,
                                     mElement->OwnerDoc()->GetDocumentURI(),
                                     domNode, linkTypes & nsStyleLinkElement::ePREFETCH);
        return;
      }
    }
  }

  if (linkTypes & nsStyleLinkElement::ePRECONNECT) {
    nsCOMPtr<nsIURI> uri(GetURI());
    if (uri && mElement->OwnerDoc()) {
      mElement->OwnerDoc()->MaybePreconnect(uri,
        mElement->AttrValueToCORSMode(mElement->GetParsedAttr(nsGkAtoms::crossorigin)));
      return;
    }
  }

  if (linkTypes & nsStyleLinkElement::eDNS_PREFETCH) {
    if (nsHTMLDNSPrefetch::IsAllowed(mElement->OwnerDoc())) {
      nsHTMLDNSPrefetch::PrefetchLow(this);
    }
  }
}

void
Link::CancelPrefetch()
{
  nsCOMPtr<nsIPrefetchService> prefetchService(do_GetService(NS_PREFETCHSERVICE_CONTRACTID));
  if (prefetchService) {
    nsCOMPtr<nsIURI> uri(GetURI());
    if (uri) {
      nsCOMPtr<nsIDOMNode> domNode = GetAsDOMNode(mElement);
      prefetchService->CancelPrefetchURI(uri, domNode);
    }
  }
}

void
Link::SetLinkState(nsLinkState aState)
{
  NS_ASSERTION(mRegistered,
               "Setting the link state of an unregistered Link!");
  NS_ASSERTION(mLinkState != aState,
               "Setting state to the currently set state!");

  // Set our current state as appropriate.
  mLinkState = aState;

  // Per IHistory interface documentation, we are no longer registered.
  mRegistered = false;

  MOZ_ASSERT(LinkState() == NS_EVENT_STATE_VISITED ||
             LinkState() == NS_EVENT_STATE_UNVISITED,
             "Unexpected state obtained from LinkState()!");

  // Tell the element to update its visited state
  mElement->UpdateState(true);
}

EventStates
Link::LinkState() const
{
  // We are a constant method, but we are just lazily doing things and have to
  // track that state.  Cast away that constness!
  Link *self = const_cast<Link *>(this);

  Element *element = self->mElement;

  // If we have not yet registered for notifications and need to,
  // due to our href changing, register now!
  if (!mRegistered && mNeedsRegistration && element->IsInComposedDoc()) {
    // Only try and register once.
    self->mNeedsRegistration = false;

    nsCOMPtr<nsIURI> hrefURI(GetURI());

    // Assume that we are not visited until we are told otherwise.
    self->mLinkState = eLinkState_Unvisited;

    // Make sure the href attribute has a valid link (bug 23209).
    // If we have a good href, register with History if available.
    if (mHistory && hrefURI) {
      nsresult rv = mHistory->RegisterVisitedCallback(hrefURI, self);
      if (NS_SUCCEEDED(rv)) {
        self->mRegistered = true;

        // And make sure we are in the document's link map.
        element->GetComposedDoc()->AddStyleRelevantLink(self);
      }
    }
  }

  // Otherwise, return our known state.
  if (mLinkState == eLinkState_Visited) {
    return NS_EVENT_STATE_VISITED;
  }

  if (mLinkState == eLinkState_Unvisited) {
    return NS_EVENT_STATE_UNVISITED;
  }

  return EventStates();
}

nsIURI*
Link::GetURI() const
{
  // If we have this URI cached, use it.
  if (mCachedURI) {
    return mCachedURI;
  }

  // Otherwise obtain it.
  Link *self = const_cast<Link *>(this);
  Element *element = self->mElement;
  mCachedURI = element->GetHrefURI();

  return mCachedURI;
}

void
Link::SetProtocol(const nsAString &aProtocol)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  nsAString::const_iterator start, end;
  aProtocol.BeginReading(start);
  aProtocol.EndReading(end);
  nsAString::const_iterator iter(start);
  (void)FindCharInReadable(':', iter, end);
  (void)uri->SetScheme(NS_ConvertUTF16toUTF8(Substring(start, iter)));

  SetHrefAttribute(uri);
}

void
Link::SetPassword(const nsAString &aPassword)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  uri->SetPassword(NS_ConvertUTF16toUTF8(aPassword));
  SetHrefAttribute(uri);
}

void
Link::SetUsername(const nsAString &aUsername)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  uri->SetUsername(NS_ConvertUTF16toUTF8(aUsername));
  SetHrefAttribute(uri);
}

void
Link::SetHost(const nsAString &aHost)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  (void)uri->SetHostPort(NS_ConvertUTF16toUTF8(aHost));
  SetHrefAttribute(uri);
}

void
Link::SetHostname(const nsAString &aHostname)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  (void)uri->SetHost(NS_ConvertUTF16toUTF8(aHostname));
  SetHrefAttribute(uri);
}

void
Link::SetPathname(const nsAString &aPathname)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  nsCOMPtr<nsIURL> url(do_QueryInterface(uri));
  if (!url) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  (void)url->SetFilePath(NS_ConvertUTF16toUTF8(aPathname));
  SetHrefAttribute(uri);
}

void
Link::SetSearch(const nsAString& aSearch)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  nsCOMPtr<nsIURL> url(do_QueryInterface(uri));
  if (!url) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  (void)url->SetQuery(NS_ConvertUTF16toUTF8(aSearch));
  SetHrefAttribute(uri);
}

void
Link::SetPort(const nsAString &aPort)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  nsresult rv;
  nsAutoString portStr(aPort);

  // nsIURI uses -1 as default value.
  int32_t port = -1;
  if (!aPort.IsEmpty()) {
    port = portStr.ToInteger(&rv);
    if (NS_FAILED(rv)) {
      return;
    }
  }

  (void)uri->SetPort(port);
  SetHrefAttribute(uri);
}

void
Link::SetHash(const nsAString &aHash)
{
  nsCOMPtr<nsIURI> uri(GetURIToMutate());
  if (!uri) {
    // Ignore failures to be compatible with NS4.
    return;
  }

  (void)uri->SetRef(NS_ConvertUTF16toUTF8(aHash));
  SetHrefAttribute(uri);
}

void
Link::GetOrigin(nsAString &aOrigin)
{
  aOrigin.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    return;
  }

  nsString origin;
  nsContentUtils::GetUTFOrigin(uri, origin);
  aOrigin.Assign(origin);
}

void
Link::GetProtocol(nsAString &_protocol)
{
  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    _protocol.AssignLiteral("http");
  }
  else {
    nsAutoCString scheme;
    (void)uri->GetScheme(scheme);
    CopyASCIItoUTF16(scheme, _protocol);
  }
  _protocol.Append(char16_t(':'));
}

void
Link::GetUsername(nsAString& aUsername)
{
  aUsername.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    return;
  }

  nsAutoCString username;
  uri->GetUsername(username);
  CopyASCIItoUTF16(username, aUsername);
}

void
Link::GetPassword(nsAString &aPassword)
{
  aPassword.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    return;
  }

  nsAutoCString password;
  uri->GetPassword(password);
  CopyASCIItoUTF16(password, aPassword);
}

void
Link::GetHost(nsAString &_host)
{
  _host.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    // Do not throw!  Not having a valid URI should result in an empty string.
    return;
  }

  nsAutoCString hostport;
  nsresult rv = uri->GetHostPort(hostport);
  if (NS_SUCCEEDED(rv)) {
    CopyUTF8toUTF16(hostport, _host);
  }
}

void
Link::GetHostname(nsAString &_hostname)
{
  _hostname.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    // Do not throw!  Not having a valid URI should result in an empty string.
    return;
  }

  nsContentUtils::GetHostOrIPv6WithBrackets(uri, _hostname);
}

void
Link::GetPathname(nsAString &_pathname)
{
  _pathname.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  nsCOMPtr<nsIURL> url(do_QueryInterface(uri));
  if (!url) {
    // Do not throw!  Not having a valid URI or URL should result in an empty
    // string.
    return;
  }

  nsAutoCString file;
  nsresult rv = url->GetFilePath(file);
  if (NS_SUCCEEDED(rv)) {
    CopyUTF8toUTF16(file, _pathname);
  }
}

void
Link::GetSearch(nsAString &_search)
{
  _search.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  nsCOMPtr<nsIURL> url(do_QueryInterface(uri));
  if (!url) {
    // Do not throw!  Not having a valid URI or URL should result in an empty
    // string.
    return;
  }

  nsAutoCString search;
  nsresult rv = url->GetQuery(search);
  if (NS_SUCCEEDED(rv) && !search.IsEmpty()) {
    CopyUTF8toUTF16(NS_LITERAL_CSTRING("?") + search, _search);
  }
}

void
Link::GetPort(nsAString &_port)
{
  _port.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    // Do not throw!  Not having a valid URI should result in an empty string.
    return;
  }

  int32_t port;
  nsresult rv = uri->GetPort(&port);
  // Note that failure to get the port from the URI is not necessarily a bad
  // thing.  Some URIs do not have a port.
  if (NS_SUCCEEDED(rv) && port != -1) {
    nsAutoString portStr;
    portStr.AppendInt(port, 10);
    _port.Assign(portStr);
  }
}

void
Link::GetHash(nsAString &_hash)
{
  _hash.Truncate();

  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    // Do not throw!  Not having a valid URI should result in an empty
    // string.
    return;
  }

  nsAutoCString ref;
  nsresult rv = uri->GetRef(ref);
  if (NS_SUCCEEDED(rv) && !ref.IsEmpty()) {
    _hash.Assign(char16_t('#'));
    if (nsContentUtils::GettersDecodeURLHash()) {
      NS_UnescapeURL(ref); // XXX may result in random non-ASCII bytes!
    }
    AppendUTF8toUTF16(ref, _hash);
  }
}

void
Link::ResetLinkState(bool aNotify, bool aHasHref)
{
  nsLinkState defaultState;

  // The default state for links with an href is unvisited.
  if (aHasHref) {
    defaultState = eLinkState_Unvisited;
  } else {
    defaultState = eLinkState_NotLink;
  }

  // If !mNeedsRegstration, then either we've never registered, or we're
  // currently registered; in either case, we should remove ourself
  // from the doc and the history.
  if (!mNeedsRegistration && mLinkState != eLinkState_NotLink) {
    nsIDocument *doc = mElement->GetComposedDoc();
    if (doc && (mRegistered || mLinkState == eLinkState_Visited)) {
      // Tell the document to forget about this link if we've registered
      // with it before.
      doc->ForgetLink(this);
    }

    UnregisterFromHistory();
  }

  // If we have an href, we should register with the history.
  mNeedsRegistration = aHasHref;

  // If we've cached the URI, reset always invalidates it.
  mCachedURI = nullptr;

  // Update our state back to the default.
  mLinkState = defaultState;

  // We have to be very careful here: if aNotify is false we do NOT
  // want to call UpdateState, because that will call into LinkState()
  // and try to start off loads, etc.  But ResetLinkState is called
  // with aNotify false when things are in inconsistent states, so
  // we'll get confused in that situation.  Instead, just silently
  // update the link state on mElement. Since we might have set the
  // link state to unvisited, make sure to update with that state if
  // required.
  if (aNotify) {
    mElement->UpdateState(aNotify);
  } else {
    if (mLinkState == eLinkState_Unvisited) {
      mElement->UpdateLinkState(NS_EVENT_STATE_UNVISITED);
    } else {
      mElement->UpdateLinkState(EventStates());
    }
  }
}

void
Link::UnregisterFromHistory()
{
  // If we are not registered, we have nothing to do.
  if (!mRegistered) {
    return;
  }

  NS_ASSERTION(mCachedURI, "mRegistered is true, but we have no cached URI?!");

  // And tell History to stop tracking us.
  if (mHistory) {
    nsresult rv = mHistory->UnregisterVisitedCallback(mCachedURI, this);
    NS_ASSERTION(NS_SUCCEEDED(rv), "This should only fail if we misuse the API!");
    if (NS_SUCCEEDED(rv)) {
      mRegistered = false;
    }
  }
}

already_AddRefed<nsIURI>
Link::GetURIToMutate()
{
  nsCOMPtr<nsIURI> uri(GetURI());
  if (!uri) {
    return nullptr;
  }
  nsCOMPtr<nsIURI> clone;
  (void)uri->Clone(getter_AddRefs(clone));
  return clone.forget();
}

void
Link::SetHrefAttribute(nsIURI *aURI)
{
  NS_ASSERTION(aURI, "Null URI is illegal!");

  // if we change this code to not reserialize we need to do something smarter
  // in SetProtocol because changing the protocol of an URI can change the
  // "nature" of the nsIURL/nsIURI implementation.
  nsAutoCString href;
  (void)aURI->GetSpec(href);
  (void)mElement->SetAttr(kNameSpaceID_None, nsGkAtoms::href,
                          NS_ConvertUTF8toUTF16(href), true);
}

size_t
Link::SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const
{
  size_t n = 0;

  if (mCachedURI) {
    nsCOMPtr<nsISizeOf> iface = do_QueryInterface(mCachedURI);
    if (iface) {
      n += iface->SizeOfIncludingThis(aMallocSizeOf);
    }
  }

  // The following members don't need to be measured:
  // - mElement, because it is a pointer-to-self used to avoid QIs
  // - mHistory, because it is non-owning

  return n;
}

} // namespace dom
} // namespace mozilla