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/* -*- 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
#ifndef mozilla_dom_HTMLDNSPrefetch_h___
#define mozilla_dom_HTMLDNSPrefetch_h___
#include "nsCOMPtr.h"
#include "nsIRequest.h"
#include "nsString.h"
#include "nsIDNSService.h"
class nsITimer;
class nsIURI;
namespace mozilla {
class OriginAttributes;
namespace net {
class NeckoParent;
} // namespace net
namespace dom {
class Document;
class Element;
class SupportsDNSPrefetch;
class HTMLDNSPrefetch {
public:
// The required aDocument parameter is the context requesting the prefetch -
// under certain circumstances (e.g. headers, or security context) associated
// with the context the prefetch will not be performed.
static bool IsAllowed(Document* aDocument);
static nsresult Initialize();
static nsresult Shutdown();
// Call one of the Prefetch* methods to start the lookup.
//
// The URI versions will defer DNS lookup until pageload is
// complete, while the string versions submit the lookup to
// the DNS system immediately. The URI version is somewhat lighter
// weight, but its request is also more likely to be dropped due to a
// full queue and it may only be used from the main thread.
//
// If you are planning to use the methods with the OriginAttributes param, be
// sure that you pass a partitioned one. See StoragePrincipalHelper.h to know
// more.
enum class Priority {
Low,
Medium,
High,
};
enum class PrefetchSource {
LinkDnsPrefetch,
AnchorSpeculativePrefetch,
};
static nsresult DeferPrefetch(SupportsDNSPrefetch& aSupports,
Element& aElement, Priority aPriority);
static void SendRequest(Element& aElement, nsIDNSService::DNSFlags aFlags);
static nsresult Prefetch(
const nsAString& host, bool isHttps,
const OriginAttributes& aPartitionedPrincipalOriginAttributes,
nsIRequest::TRRMode aTRRMode, Priority);
static nsresult CancelPrefetch(
const nsAString& host, bool isHttps,
const OriginAttributes& aPartitionedPrincipalOriginAttributes,
nsIRequest::TRRMode aTRRMode, Priority, nsresult aReason);
static nsresult CancelPrefetch(SupportsDNSPrefetch&, Element&, Priority,
nsresult aReason);
static void ElementDestroyed(Element&, SupportsDNSPrefetch&);
static nsIDNSService::DNSFlags PriorityToDNSServiceFlags(Priority);
private:
static nsresult Prefetch(
const nsAString& host, bool isHttps,
const OriginAttributes& aPartitionedPrincipalOriginAttributes,
nsIDNSService::DNSFlags flags);
static nsresult CancelPrefetch(
const nsAString& hostname, bool isHttps,
const OriginAttributes& aPartitionedPrincipalOriginAttributes,
nsIDNSService::DNSFlags flags, nsresult aReason);
friend class net::NeckoParent;
};
// Elements that support DNS prefetch are expected to subclass this.
class SupportsDNSPrefetch {
public:
bool IsInDNSPrefetch() { return mInDNSPrefetch; }
void SetIsInDNSPrefetch() { mInDNSPrefetch = true; }
void ClearIsInDNSPrefetch() { mInDNSPrefetch = false; }
void DNSPrefetchRequestStarted() {
mDNSPrefetchDeferred = false;
mDNSPrefetchRequested = true;
}
void DNSPrefetchRequestDeferred() {
mDNSPrefetchDeferred = true;
mDNSPrefetchRequested = false;
}
bool IsDNSPrefetchRequestDeferred() const { return mDNSPrefetchDeferred; }
// This could be a virtual function or something like that, but that would
// cause our subclasses to grow by two pointers, rather than just 1 byte at
// most.
nsIURI* GetURIForDNSPrefetch(Element& aOwner);
protected:
SupportsDNSPrefetch()
: mInDNSPrefetch(false),
mDNSPrefetchRequested(false),
mDNSPrefetchDeferred(false),
mDestroyedCalled(false) {}
void CancelDNSPrefetch(Element& aOwner);
void TryDNSPrefetch(Element& aOwner, HTMLDNSPrefetch::PrefetchSource aSource);
// This MUST be called on the destructor of the Element subclass.
// Our own destructor ensures that.
void Destroyed(Element& aOwner) {
MOZ_DIAGNOSTIC_ASSERT(!mDestroyedCalled,
"Multiple calls to SupportsDNSPrefetch::Destroyed?");
mDestroyedCalled = true;
if (mInDNSPrefetch) {
HTMLDNSPrefetch::ElementDestroyed(aOwner, *this);
}
}
~SupportsDNSPrefetch() {
MOZ_DIAGNOSTIC_ASSERT(mDestroyedCalled,
"Need to call SupportsDNSPrefetch::Destroyed "
"from the owner element");
}
private:
bool mInDNSPrefetch : 1;
bool mDNSPrefetchRequested : 1;
bool mDNSPrefetchDeferred : 1;
bool mDestroyedCalled : 1;
};
} // namespace dom
} // namespace mozilla
#endif