gecko/uriloader/prefetch/nsPrefetchService.cpp

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/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 2002
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Darin Fisher <darin@netscape.com> (original author)
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include "nsPrefetchService.h"
#include "nsICacheSession.h"
#include "nsICacheService.h"
#include "nsIServiceManager.h"
#include "nsICategoryManager.h"
#include "nsIObserverService.h"
#include "nsIPrefService.h"
#include "nsIPrefBranch2.h"
#include "nsIDocCharset.h"
#include "nsIWebProgress.h"
#include "nsCURILoader.h"
#include "nsICachingChannel.h"
#include "nsICacheVisitor.h"
#include "nsIHttpChannel.h"
#include "nsIURL.h"
#include "nsISimpleEnumerator.h"
#include "nsNetUtil.h"
#include "nsString.h"
#include "nsXPIDLString.h"
#include "nsReadableUtils.h"
#include "nsStreamUtils.h"
#include "nsAutoPtr.h"
#include "prtime.h"
#include "prlog.h"
#include "plstr.h"
#if defined(PR_LOGGING)
//
// To enable logging (see prlog.h for full details):
//
// set NSPR_LOG_MODULES=nsPrefetch:5
// set NSPR_LOG_FILE=prefetch.log
//
// this enables PR_LOG_ALWAYS level information and places all output in
// the file http.log
//
static PRLogModuleInfo *gPrefetchLog;
#endif
#define LOG(args) PR_LOG(gPrefetchLog, 4, args)
#define LOG_ENABLED() PR_LOG_TEST(gPrefetchLog, 4)
#define PREFETCH_PREF "network.prefetch-next"
//-----------------------------------------------------------------------------
// helpers
//-----------------------------------------------------------------------------
static inline PRUint32
PRTimeToSeconds(PRTime t_usec)
{
PRTime usec_per_sec;
PRUint32 t_sec;
LL_I2L(usec_per_sec, PR_USEC_PER_SEC);
LL_DIV(t_usec, t_usec, usec_per_sec);
LL_L2I(t_sec, t_usec);
return t_sec;
}
#define NowInSeconds() PRTimeToSeconds(PR_Now())
//-----------------------------------------------------------------------------
// nsPrefetchQueueEnumerator
//-----------------------------------------------------------------------------
class nsPrefetchQueueEnumerator : public nsISimpleEnumerator
{
public:
NS_DECL_ISUPPORTS
NS_DECL_NSISIMPLEENUMERATOR
nsPrefetchQueueEnumerator(nsPrefetchService *aService);
~nsPrefetchQueueEnumerator();
private:
void Increment();
nsRefPtr<nsPrefetchService> mService;
nsRefPtr<nsPrefetchNode> mCurrent;
PRBool mStarted;
};
//-----------------------------------------------------------------------------
// nsPrefetchQueueEnumerator <public>
//-----------------------------------------------------------------------------
nsPrefetchQueueEnumerator::nsPrefetchQueueEnumerator(nsPrefetchService *aService)
: mService(aService)
, mStarted(PR_FALSE)
{
Increment();
}
nsPrefetchQueueEnumerator::~nsPrefetchQueueEnumerator()
{
}
//-----------------------------------------------------------------------------
// nsPrefetchQueueEnumerator::nsISimpleEnumerator
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchQueueEnumerator::HasMoreElements(PRBool *aHasMore)
{
*aHasMore = (mCurrent != nsnull);
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchQueueEnumerator::GetNext(nsISupports **aItem)
{
if (!mCurrent) return NS_ERROR_FAILURE;
NS_ADDREF(*aItem = static_cast<nsIDOMLoadStatus*>(mCurrent.get()));
Increment();
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchQueueEnumerator <private>
//-----------------------------------------------------------------------------
void
nsPrefetchQueueEnumerator::Increment()
{
if (!mStarted) {
// If the service is currently serving a request, it won't be in
// the pending queue, so we return it first. If it isn't, we'll
// just start with the pending queue.
mStarted = PR_TRUE;
mCurrent = mService->GetCurrentNode();
if (!mCurrent)
mCurrent = mService->GetQueueHead();
return;
}
if (mCurrent) {
if (mCurrent == mService->GetCurrentNode()) {
// If we just returned the node being processed by the service,
// start with the pending queue
mCurrent = mService->GetQueueHead();
}
else {
// Otherwise just advance to the next item in the queue
mCurrent = mCurrent->mNext;
}
}
}
//-----------------------------------------------------------------------------
// nsPrefetchQueueEnumerator::nsISupports
//-----------------------------------------------------------------------------
NS_IMPL_ISUPPORTS1(nsPrefetchQueueEnumerator, nsISimpleEnumerator)
//-----------------------------------------------------------------------------
// nsPrefetchNode <public>
//-----------------------------------------------------------------------------
nsPrefetchNode::nsPrefetchNode(nsPrefetchService *aService,
nsIURI *aURI,
nsIURI *aReferrerURI,
nsIDOMNode *aSource)
: mNext(nsnull)
, mURI(aURI)
, mReferrerURI(aReferrerURI)
, mService(aService)
, mChannel(nsnull)
, mState(nsIDOMLoadStatus::UNINITIALIZED)
, mBytesRead(0)
{
mSource = do_GetWeakReference(aSource);
}
nsresult
nsPrefetchNode::OpenChannel()
{
nsresult rv = NS_NewChannel(getter_AddRefs(mChannel),
mURI,
nsnull, nsnull, this,
nsIRequest::LOAD_BACKGROUND |
nsICachingChannel::LOAD_ONLY_IF_MODIFIED);
NS_ENSURE_SUCCESS(rv, rv);
// configure HTTP specific stuff
nsCOMPtr<nsIHttpChannel> httpChannel =
do_QueryInterface(mChannel);
if (httpChannel) {
httpChannel->SetReferrer(mReferrerURI);
httpChannel->SetRequestHeader(
NS_LITERAL_CSTRING("X-Moz"),
NS_LITERAL_CSTRING("prefetch"),
PR_FALSE);
}
rv = mChannel->AsyncOpen(this, nsnull);
NS_ENSURE_SUCCESS(rv, rv);
mState = nsIDOMLoadStatus::REQUESTED;
return NS_OK;
}
nsresult
nsPrefetchNode::CancelChannel(nsresult error)
{
mChannel->Cancel(error);
mChannel = nsnull;
mState = nsIDOMLoadStatus::UNINITIALIZED;
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchNode::nsISupports
//-----------------------------------------------------------------------------
NS_IMPL_ISUPPORTS5(nsPrefetchNode,
nsIDOMLoadStatus,
nsIRequestObserver,
nsIStreamListener,
nsIInterfaceRequestor,
nsIChannelEventSink)
//-----------------------------------------------------------------------------
// nsPrefetchNode::nsIStreamListener
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchNode::OnStartRequest(nsIRequest *aRequest,
nsISupports *aContext)
{
nsresult rv;
nsCOMPtr<nsICachingChannel> cachingChannel =
do_QueryInterface(aRequest, &rv);
if (NS_FAILED(rv)) return rv;
// no need to prefetch a document that is already in the cache
PRBool fromCache;
if (NS_SUCCEEDED(cachingChannel->IsFromCache(&fromCache)) &&
fromCache) {
LOG(("document is already in the cache; canceling prefetch\n"));
return NS_BINDING_ABORTED;
}
//
// no need to prefetch a document that must be requested fresh each
// and every time.
//
nsCOMPtr<nsISupports> cacheToken;
cachingChannel->GetCacheToken(getter_AddRefs(cacheToken));
if (!cacheToken)
return NS_ERROR_ABORT; // bail, no cache entry
nsCOMPtr<nsICacheEntryInfo> entryInfo =
do_QueryInterface(cacheToken, &rv);
if (NS_FAILED(rv)) return rv;
PRUint32 expTime;
if (NS_SUCCEEDED(entryInfo->GetExpirationTime(&expTime))) {
if (NowInSeconds() >= expTime) {
LOG(("document cannot be reused from cache; "
"canceling prefetch\n"));
return NS_BINDING_ABORTED;
}
}
mState = nsIDOMLoadStatus::RECEIVING;
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::OnDataAvailable(nsIRequest *aRequest,
nsISupports *aContext,
nsIInputStream *aStream,
PRUint32 aOffset,
PRUint32 aCount)
{
PRUint32 bytesRead = 0;
aStream->ReadSegments(NS_DiscardSegment, nsnull, aCount, &bytesRead);
mBytesRead += bytesRead;
LOG(("prefetched %u bytes [offset=%u]\n", bytesRead, aOffset));
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::OnStopRequest(nsIRequest *aRequest,
nsISupports *aContext,
nsresult aStatus)
{
LOG(("done prefetching [status=%x]\n", aStatus));
mState = nsIDOMLoadStatus::LOADED;
if (mBytesRead == 0 && aStatus == NS_OK) {
// we didn't need to read (because LOAD_ONLY_IF_MODIFIED was
// specified), but the object should report loadedSize as if it
// did.
mChannel->GetContentLength(&mBytesRead);
}
mService->NotifyLoadCompleted(this);
mService->ProcessNextURI();
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchNode::nsIInterfaceRequestor
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchNode::GetInterface(const nsIID &aIID, void **aResult)
{
if (aIID.Equals(NS_GET_IID(nsIChannelEventSink))) {
NS_ADDREF_THIS();
*aResult = static_cast<nsIChannelEventSink *>(this);
return NS_OK;
}
return NS_ERROR_NO_INTERFACE;
}
//-----------------------------------------------------------------------------
// nsPrefetchNode::nsIChannelEventSink
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchNode::OnChannelRedirect(nsIChannel *aOldChannel,
nsIChannel *aNewChannel,
PRUint32 aFlags)
{
nsCOMPtr<nsIURI> newURI;
nsresult rv = aNewChannel->GetURI(getter_AddRefs(newURI));
if (NS_FAILED(rv))
return rv;
nsCOMPtr<nsICachingChannel> oldCachingChannel =
do_QueryInterface(aOldChannel);
PRBool match;
rv = newURI->SchemeIs("http", &match);
if (NS_FAILED(rv) || !match) {
rv = newURI->SchemeIs("https", &match);
if (NS_FAILED(rv) || !match) {
LOG(("rejected: URL is not of type http/https\n"));
return NS_ERROR_ABORT;
}
}
// HTTP request headers are not automatically forwarded to the new channel.
nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aNewChannel);
NS_ENSURE_STATE(httpChannel);
httpChannel->SetRequestHeader(NS_LITERAL_CSTRING("X-Moz"),
NS_LITERAL_CSTRING("prefetch"),
PR_FALSE);
mChannel = aNewChannel;
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchService <public>
//-----------------------------------------------------------------------------
nsPrefetchService::nsPrefetchService()
: mQueueHead(nsnull)
, mQueueTail(nsnull)
, mStopCount(0)
, mHaveProcessed(PR_FALSE)
, mDisabled(PR_TRUE)
{
}
nsPrefetchService::~nsPrefetchService()
{
// cannot reach destructor if prefetch in progress (listener owns reference
// to this service)
EmptyQueue();
}
nsresult
nsPrefetchService::Init()
{
#if defined(PR_LOGGING)
if (!gPrefetchLog)
gPrefetchLog = PR_NewLogModule("nsPrefetch");
#endif
nsresult rv;
// read prefs and hook up pref observer
nsCOMPtr<nsIPrefBranch2> prefs(do_GetService(NS_PREFSERVICE_CONTRACTID, &rv));
if (NS_SUCCEEDED(rv)) {
PRBool enabled;
rv = prefs->GetBoolPref(PREFETCH_PREF, &enabled);
if (NS_SUCCEEDED(rv) && enabled)
mDisabled = PR_FALSE;
prefs->AddObserver(PREFETCH_PREF, this, PR_TRUE);
}
// Observe xpcom-shutdown event
nsCOMPtr<nsIObserverService> observerServ(
do_GetService("@mozilla.org/observer-service;1", &rv));
if (NS_FAILED(rv)) return rv;
rv = observerServ->AddObserver(this, NS_XPCOM_SHUTDOWN_OBSERVER_ID, PR_TRUE);
if (NS_FAILED(rv)) return rv;
if (!mDisabled)
AddProgressListener();
return NS_OK;
}
void
nsPrefetchService::ProcessNextURI()
{
nsresult rv;
nsCOMPtr<nsIURI> uri, referrer;
mCurrentNode = nsnull;
do {
rv = DequeueNode(getter_AddRefs(mCurrentNode));
if (NS_FAILED(rv)) break;
#if defined(PR_LOGGING)
if (LOG_ENABLED()) {
nsCAutoString spec;
mCurrentNode->mURI->GetSpec(spec);
LOG(("ProcessNextURI [%s]\n", spec.get()));
}
#endif
//
// if opening the channel fails, then just skip to the next uri
//
rv = mCurrentNode->OpenChannel();
}
while (NS_FAILED(rv));
}
void
nsPrefetchService::NotifyLoadRequested(nsPrefetchNode *node)
{
nsresult rv;
nsCOMPtr<nsIObserverService> observerService =
do_GetService("@mozilla.org/observer-service;1", &rv);
if (NS_FAILED(rv)) return;
observerService->NotifyObservers(static_cast<nsIDOMLoadStatus*>(node),
"prefetch-load-requested", nsnull);
}
void
nsPrefetchService::NotifyLoadCompleted(nsPrefetchNode *node)
{
nsresult rv;
nsCOMPtr<nsIObserverService> observerService =
do_GetService("@mozilla.org/observer-service;1", &rv);
if (NS_FAILED(rv)) return;
observerService->NotifyObservers(static_cast<nsIDOMLoadStatus*>(node),
"prefetch-load-completed", nsnull);
}
//-----------------------------------------------------------------------------
// nsPrefetchService <private>
//-----------------------------------------------------------------------------
void
nsPrefetchService::AddProgressListener()
{
// Register as an observer for the document loader
nsCOMPtr<nsIWebProgress> progress =
do_GetService(NS_DOCUMENTLOADER_SERVICE_CONTRACTID);
if (progress)
progress->AddProgressListener(this, nsIWebProgress::NOTIFY_STATE_DOCUMENT);
}
void
nsPrefetchService::RemoveProgressListener()
{
// Register as an observer for the document loader
nsCOMPtr<nsIWebProgress> progress =
do_GetService(NS_DOCUMENTLOADER_SERVICE_CONTRACTID);
if (progress)
progress->RemoveProgressListener(this);
}
nsresult
nsPrefetchService::EnqueueNode(nsPrefetchNode *aNode)
{
NS_ADDREF(aNode);
if (!mQueueTail) {
mQueueHead = aNode;
mQueueTail = aNode;
}
else {
mQueueTail->mNext = aNode;
mQueueTail = aNode;
}
return NS_OK;
}
nsresult
nsPrefetchService::EnqueueURI(nsIURI *aURI,
nsIURI *aReferrerURI,
nsIDOMNode *aSource,
nsPrefetchNode **aNode)
{
nsPrefetchNode *node = new nsPrefetchNode(this, aURI, aReferrerURI,
aSource);
if (!node)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*aNode = node);
return EnqueueNode(node);
}
nsresult
nsPrefetchService::DequeueNode(nsPrefetchNode **node)
{
if (!mQueueHead)
return NS_ERROR_NOT_AVAILABLE;
// give the ref to the caller
*node = mQueueHead;
mQueueHead = mQueueHead->mNext;
(*node)->mNext = nsnull;
if (!mQueueHead)
mQueueTail = nsnull;
return NS_OK;
}
void
nsPrefetchService::EmptyQueue()
{
do {
nsRefPtr<nsPrefetchNode> node;
DequeueNode(getter_AddRefs(node));
} while (mQueueHead);
}
void
nsPrefetchService::StartPrefetching()
{
//
// at initialization time we might miss the first DOCUMENT START
// notification, so we have to be careful to avoid letting our
// stop count go negative.
//
if (mStopCount > 0)
mStopCount--;
LOG(("StartPrefetching [stopcount=%d]\n", mStopCount));
// only start prefetching after we've received enough DOCUMENT
// STOP notifications. we do this inorder to defer prefetching
// until after all sub-frames have finished loading.
if (mStopCount == 0 && !mCurrentNode) {
mHaveProcessed = PR_TRUE;
ProcessNextURI();
}
}
void
nsPrefetchService::StopPrefetching()
{
mStopCount++;
LOG(("StopPrefetching [stopcount=%d]\n", mStopCount));
// only kill the prefetch queue if we've actually started prefetching.
if (!mCurrentNode)
return;
mCurrentNode->CancelChannel(NS_BINDING_ABORTED);
mCurrentNode = nsnull;
EmptyQueue();
}
//-----------------------------------------------------------------------------
// nsPrefetchService::nsISupports
//-----------------------------------------------------------------------------
NS_IMPL_ISUPPORTS4(nsPrefetchService,
nsIPrefetchService,
nsIWebProgressListener,
nsIObserver,
nsISupportsWeakReference)
//-----------------------------------------------------------------------------
// nsPrefetchService::nsIPrefetchService
//-----------------------------------------------------------------------------
nsresult
nsPrefetchService::Prefetch(nsIURI *aURI,
nsIURI *aReferrerURI,
nsIDOMNode *aSource,
PRBool aExplicit)
{
nsresult rv;
NS_ENSURE_ARG_POINTER(aURI);
NS_ENSURE_ARG_POINTER(aReferrerURI);
#if defined(PR_LOGGING)
if (LOG_ENABLED()) {
nsCAutoString spec;
aURI->GetSpec(spec);
LOG(("PrefetchURI [%s]\n", spec.get()));
}
#endif
if (mDisabled) {
LOG(("rejected: prefetch service is disabled\n"));
return NS_ERROR_ABORT;
}
//
// XXX we should really be asking the protocol handler if it supports
// caching, so we can determine if there is any value to prefetching.
// for now, we'll only prefetch http links since we know that's the
// most common case. ignore https links since https content only goes
// into the memory cache.
//
// XXX we might want to either leverage nsIProtocolHandler::protocolFlags
// or possibly nsIRequest::loadFlags to determine if this URI should be
// prefetched.
//
PRBool match;
rv = aURI->SchemeIs("http", &match);
if (NS_FAILED(rv) || !match) {
rv = aURI->SchemeIs("https", &match);
if (NS_FAILED(rv) || !match) {
LOG(("rejected: URL is not of type http/https\n"));
return NS_ERROR_ABORT;
}
}
//
// the referrer URI must be http:
//
rv = aReferrerURI->SchemeIs("http", &match);
if (NS_FAILED(rv) || !match) {
rv = aReferrerURI->SchemeIs("https", &match);
if (NS_FAILED(rv) || !match) {
LOG(("rejected: referrer URL is neither http nor https\n"));
return NS_ERROR_ABORT;
}
}
// skip URLs that contain query strings, except URLs for which prefetching
// has been explicitly requested.
if (!aExplicit) {
nsCOMPtr<nsIURL> url(do_QueryInterface(aURI, &rv));
if (NS_FAILED(rv)) return rv;
nsCAutoString query;
rv = url->GetQuery(query);
if (NS_FAILED(rv) || !query.IsEmpty()) {
LOG(("rejected: URL has a query string\n"));
return NS_ERROR_ABORT;
}
}
//
// cancel if being prefetched
//
if (mCurrentNode) {
PRBool equals;
if (NS_SUCCEEDED(mCurrentNode->mURI->Equals(aURI, &equals)) && equals) {
LOG(("rejected: URL is already being prefetched\n"));
return NS_ERROR_ABORT;
}
}
//
// cancel if already on the prefetch queue
//
nsPrefetchNode *node = mQueueHead;
for (; node; node = node->mNext) {
PRBool equals;
if (NS_SUCCEEDED(node->mURI->Equals(aURI, &equals)) && equals) {
LOG(("rejected: URL is already on prefetch queue\n"));
return NS_ERROR_ABORT;
}
}
nsRefPtr<nsPrefetchNode> enqueuedNode;
rv = EnqueueURI(aURI, aReferrerURI, aSource,
getter_AddRefs(enqueuedNode));
NS_ENSURE_SUCCESS(rv, rv);
NotifyLoadRequested(enqueuedNode);
// if there are no pages loading, kick off the request immediately
if (mStopCount == 0 && mHaveProcessed)
ProcessNextURI();
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchService::PrefetchURI(nsIURI *aURI,
nsIURI *aReferrerURI,
nsIDOMNode *aSource,
PRBool aExplicit)
{
return Prefetch(aURI, aReferrerURI, aSource, aExplicit);
}
NS_IMETHODIMP
nsPrefetchService::PrefetchURIForOfflineUse(nsIURI *aURI,
nsIURI *aReferrerURI,
nsIDOMNode *aSource,
PRBool aExplicit)
{
return NS_ERROR_NOT_IMPLEMENTED;
}
NS_IMETHODIMP
nsPrefetchService::EnumerateQueue(PRBool aIncludeNormalItems,
PRBool aIncludeOfflineItems,
nsISimpleEnumerator **aEnumerator)
{
NS_ENSURE_TRUE(aIncludeNormalItems && !aIncludeOfflineItems,
NS_ERROR_NOT_IMPLEMENTED);
*aEnumerator = new nsPrefetchQueueEnumerator(this);
if (!*aEnumerator) return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*aEnumerator);
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchNode::nsIDOMLoadStatus
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchNode::GetSource(nsIDOMNode **aSource)
{
*aSource = nsnull;
nsCOMPtr<nsIDOMNode> source = do_QueryReferent(mSource);
if (source)
source.swap(*aSource);
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::GetUri(nsAString &aURI)
{
nsCAutoString spec;
nsresult rv = mURI->GetSpec(spec);
NS_ENSURE_SUCCESS(rv, rv);
CopyUTF8toUTF16(spec, aURI);
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::GetTotalSize(PRInt32 *aTotalSize)
{
if (mChannel) {
return mChannel->GetContentLength(aTotalSize);
}
*aTotalSize = -1;
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::GetLoadedSize(PRInt32 *aLoadedSize)
{
*aLoadedSize = mBytesRead;
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::GetReadyState(PRUint16 *aReadyState)
{
*aReadyState = mState;
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchNode::GetStatus(PRUint16 *aStatus)
{
if (!mChannel) {
*aStatus = 0;
return NS_OK;
}
nsresult rv;
nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(mChannel, &rv);
NS_ENSURE_SUCCESS(rv, rv);
PRUint32 httpStatus;
rv = httpChannel->GetResponseStatus(&httpStatus);
if (rv == NS_ERROR_NOT_AVAILABLE) {
// Someone's calling this before we got a response... Check our
// ReadyState. If we're at RECEIVING or LOADED, then this means the
// connection errored before we got any data; return a somewhat
// sensible error code in that case.
if (mState >= nsIDOMLoadStatus::RECEIVING) {
*aStatus = NS_ERROR_NOT_AVAILABLE;
return NS_OK;
}
*aStatus = 0;
return NS_OK;
}
NS_ENSURE_SUCCESS(rv, rv);
*aStatus = PRUint16(httpStatus);
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchService::nsIWebProgressListener
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchService::OnProgressChange(nsIWebProgress *aProgress,
nsIRequest *aRequest,
PRInt32 curSelfProgress,
PRInt32 maxSelfProgress,
PRInt32 curTotalProgress,
PRInt32 maxTotalProgress)
{
NS_NOTREACHED("notification excluded in AddProgressListener(...)");
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchService::OnStateChange(nsIWebProgress* aWebProgress,
nsIRequest *aRequest,
PRUint32 progressStateFlags,
nsresult aStatus)
{
if (progressStateFlags & STATE_IS_DOCUMENT) {
if (progressStateFlags & STATE_STOP)
StartPrefetching();
else if (progressStateFlags & STATE_START)
StopPrefetching();
}
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchService::OnLocationChange(nsIWebProgress* aWebProgress,
nsIRequest* aRequest,
nsIURI *location)
{
NS_NOTREACHED("notification excluded in AddProgressListener(...)");
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchService::OnStatusChange(nsIWebProgress* aWebProgress,
nsIRequest* aRequest,
nsresult aStatus,
const PRUnichar* aMessage)
{
NS_NOTREACHED("notification excluded in AddProgressListener(...)");
return NS_OK;
}
NS_IMETHODIMP
nsPrefetchService::OnSecurityChange(nsIWebProgress *aWebProgress,
nsIRequest *aRequest,
PRUint32 state)
{
NS_NOTREACHED("notification excluded in AddProgressListener(...)");
return NS_OK;
}
//-----------------------------------------------------------------------------
// nsPrefetchService::nsIObserver
//-----------------------------------------------------------------------------
NS_IMETHODIMP
nsPrefetchService::Observe(nsISupports *aSubject,
const char *aTopic,
const PRUnichar *aData)
{
LOG(("nsPrefetchService::Observe [topic=%s]\n", aTopic));
if (!strcmp(aTopic, NS_XPCOM_SHUTDOWN_OBSERVER_ID)) {
StopPrefetching();
EmptyQueue();
mDisabled = PR_TRUE;
}
else if (!strcmp(aTopic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID)) {
nsCOMPtr<nsIPrefBranch> prefs(do_QueryInterface(aSubject));
PRBool enabled;
nsresult rv = prefs->GetBoolPref(PREFETCH_PREF, &enabled);
if (NS_SUCCEEDED(rv) && enabled) {
if (mDisabled) {
LOG(("enabling prefetching\n"));
mDisabled = PR_FALSE;
AddProgressListener();
}
}
else {
if (!mDisabled) {
LOG(("disabling prefetching\n"));
StopPrefetching();
EmptyQueue();
mDisabled = PR_TRUE;
RemoveProgressListener();
}
}
}
return NS_OK;
}
// vim: ts=4 sw=4 expandtab