1 files changed, 659 insertions, 0 deletions
diff --git a/dom/base/Link.cpp b/dom/base/Link.cpp
new file mode 100644
index 0000000000..43bbe5c3a6
--- /dev/null
+++ b/dom/base/Link.cpp
@@ -0,0 +1,659 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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