pjs/extensions/xforms/nsXFormsInstanceElement.cpp

654 строки
21 KiB
C++
Исходник Обычный вид История

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* ***** 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 XForms support.
*
* The Initial Developer of the Original Code is
* IBM Corporation.
* Portions created by the Initial Developer are Copyright (C) 2004
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Brian Ryner <bryner@brianryner.com>
* Olli Pettay <Olli.Pettay@helsinki.fi>
*
* 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 "nsXFormsInstanceElement.h"
#include "nsIDOMElement.h"
#include "nsIDOMEventTarget.h"
#include "nsIDOM3Node.h"
#include "nsIDocument.h"
#include "nsMemory.h"
#include "nsXFormsAtoms.h"
#include "nsString.h"
#include "nsIDOMEventReceiver.h"
#include "nsIDOMDOMImplementation.h"
#include "nsIXTFGenericElementWrapper.h"
#include "nsXFormsUtils.h"
#include "nsNetUtil.h"
static const char* kLoadAsData = "loadAsData";
NS_IMPL_ISUPPORTS_INHERITED6(nsXFormsInstanceElement,
nsXFormsStubElement,
nsIXFormsNSInstanceElement,
nsIInstanceElementPrivate,
nsIStreamListener,
nsIRequestObserver,
nsIInterfaceRequestor,
nsIChannelEventSink)
nsXFormsInstanceElement::nsXFormsInstanceElement()
: mElement(nsnull)
, mInitialized(PR_FALSE)
, mLazy(PR_FALSE)
{
}
NS_IMETHODIMP
nsXFormsInstanceElement::OnDestroyed()
{
if (mChannel) {
// better be a good citizen and tell the browser that we don't need this
// resource anymore.
mChannel->Cancel(NS_BINDING_ABORTED);
mChannel = nsnull;
}
mListener = nsnull;
SetInstanceDocument(nsnull);
mElement = nsnull;
return NS_OK;
}
NS_IMETHODIMP
nsXFormsInstanceElement::AttributeSet(nsIAtom *aName,
const nsAString &aNewValue)
{
if (!mInitialized || mLazy)
return NS_OK;
if (aName == nsXFormsAtoms::src) {
LoadExternalInstance(aNewValue);
}
return NS_OK;
}
NS_IMETHODIMP
nsXFormsInstanceElement::AttributeRemoved(nsIAtom *aName)
{
if (!mInitialized || mLazy)
return NS_OK;
if (aName == nsXFormsAtoms::src) {
PRBool restart = PR_FALSE;
if (mChannel) {
// looks like we are trying to remove the src attribute while we are
// already trying to load the external instance document. We'll stop
// the current load effort.
restart = PR_TRUE;
mChannel->Cancel(NS_BINDING_ABORTED);
mChannel = nsnull;
mListener = nsnull;
}
// We no longer have an external instance to use. Reset our instance
// document to whatever inline content we have.
nsresult rv = CloneInlineInstance();
// if we had already started to load an external instance document, then
// as part of that we would have told the model to wait for that external
// document to load before it finishes the model construction. Since we
// aren't loading from an external document any longer, tell the model that
// there is need to wait for us anymore.
if (restart) {
nsCOMPtr<nsIModelElementPrivate> model = GetModel();
if (model) {
model->InstanceLoadFinished(PR_TRUE);
}
}
return rv;
}
return NS_OK;
}
NS_IMETHODIMP
nsXFormsInstanceElement::OnCreated(nsIXTFGenericElementWrapper *aWrapper)
{
aWrapper->SetNotificationMask(nsIXTFElement::NOTIFY_ATTRIBUTE_SET |
nsIXTFElement::NOTIFY_ATTRIBUTE_REMOVED |
nsIXTFElement::NOTIFY_WILL_CHANGE_PARENT |
nsIXTFElement::NOTIFY_PARENT_CHANGED);
nsCOMPtr<nsIDOMElement> node;
aWrapper->GetElementNode(getter_AddRefs(node));
// It's ok to keep a weak pointer to mElement. mElement will have an owning
// reference to this object, so as long as we null out mElement in
// OnDestroyed, it will always be valid.
mElement = node;
NS_ASSERTION(mElement, "Wrapper is not an nsIDOMElement, we'll crash soon");
return NS_OK;
}
// nsIInterfaceRequestor
NS_IMETHODIMP
nsXFormsInstanceElement::GetInterface(const nsIID & aIID, void **aResult)
{
*aResult = nsnull;
return QueryInterface(aIID, aResult);
}
// nsIChannelEventSink
NS_IMETHODIMP
nsXFormsInstanceElement::OnChannelRedirect(nsIChannel *OldChannel,
nsIChannel *aNewChannel,
PRUint32 aFlags)
{
NS_PRECONDITION(aNewChannel, "Redirect without a channel?");
NS_PRECONDITION(!mLazy, "Loading an instance document for a lazy instance?");
nsCOMPtr<nsIURI> newURI;
nsresult rv = aNewChannel->GetURI(getter_AddRefs(newURI));
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_STATE(mElement);
nsCOMPtr<nsIDOMDocument> domDoc;
mElement->GetOwnerDocument(getter_AddRefs(domDoc));
nsCOMPtr<nsIDocument> doc(do_QueryInterface(domDoc));
NS_ENSURE_STATE(doc);
if (!nsXFormsUtils::CheckSameOrigin(doc, newURI)) {
nsXFormsUtils::ReportError(NS_LITERAL_STRING("instanceLoadOrigin"), domDoc);
return NS_ERROR_ABORT;
}
return NS_OK;
}
// nsIStreamListener
// It is possible that mListener could be null here. If the document hit a
// parsing error after we've already started to load the external source, then
// Mozilla will destroy all of the elements and the document in order to load
// the parser error page. This will cause mListener to become null but since
// the channel will hold a nsCOMPtr to the nsXFormsInstanceElement preventing
// it from being freed up, the channel will still be able to call the
// nsIStreamListener functions that we implement here. And calling
// mChannel->Cancel() is no guarantee that these other notifications won't come
// through if the timing is wrong. So we need to check for mElement below
// before we handle any of the stream notifications.
NS_IMETHODIMP
nsXFormsInstanceElement::OnStartRequest(nsIRequest *request, nsISupports *ctx)
{
NS_PRECONDITION(!mLazy, "Loading an instance document for a lazy instance?");
if (!mElement || !mListener) {
return NS_OK;
}
return mListener->OnStartRequest(request, ctx);
}
NS_IMETHODIMP
nsXFormsInstanceElement::OnDataAvailable(nsIRequest *aRequest,
nsISupports *ctxt,
nsIInputStream *inStr,
PRUint32 sourceOffset,
PRUint32 count)
{
NS_PRECONDITION(!mLazy, "Loading an instance document for a lazy instance?");
if (!mElement || !mListener) {
return NS_OK;
}
return mListener->OnDataAvailable(aRequest, ctxt, inStr, sourceOffset, count);
}
NS_IMETHODIMP
nsXFormsInstanceElement::OnStopRequest(nsIRequest *request, nsISupports *ctx,
nsresult status)
{
NS_PRECONDITION(!mLazy, "Loading an instance document for a lazy instance?");
if (status == NS_BINDING_ABORTED) {
// looks like our element has already been destroyed. No use continuing on.
return NS_OK;
}
mChannel = nsnull;
NS_ASSERTION(mListener, "No stream listener for document!");
mListener->OnStopRequest(request, ctx, status);
PRBool succeeded = NS_SUCCEEDED(status);
if (!succeeded) {
SetInstanceDocument(nsnull);
}
if (mDocument) {
nsCOMPtr<nsIDOMElement> docElem;
mDocument->GetDocumentElement(getter_AddRefs(docElem));
if (docElem) {
nsAutoString tagName, namespaceURI;
docElem->GetTagName(tagName);
docElem->GetNamespaceURI(namespaceURI);
if (tagName.EqualsLiteral("parsererror") &&
namespaceURI.EqualsLiteral("http://www.mozilla.org/newlayout/xml/parsererror.xml")) {
NS_WARNING("resulting instance document could not be parsed");
succeeded = PR_FALSE;
SetInstanceDocument(nsnull);
}
}
}
nsCOMPtr<nsIModelElementPrivate> model = GetModel();
if (model) {
model->InstanceLoadFinished(succeeded);
}
mListener = nsnull;
return NS_OK;
}
// nsIXFormsNSInstanceElement
NS_IMETHODIMP
nsXFormsInstanceElement::GetInstanceDocument(nsIDOMDocument **aDocument)
{
NS_IF_ADDREF(*aDocument = mDocument);
return NS_OK;
}
// nsIInstanceElementPrivate
NS_IMETHODIMP
nsXFormsInstanceElement::SetInstanceDocument(nsIDOMDocument *aDocument)
{
nsCOMPtr<nsIDocument> doc(do_QueryInterface(mDocument));
if (doc) {
doc->UnsetProperty(nsXFormsAtoms::instanceDocumentOwner);
}
mDocument = aDocument;
doc = do_QueryInterface(mDocument);
if (doc) {
// Set property to prevent an instance document loading an external instance
// document
nsresult rv = doc->SetProperty(nsXFormsAtoms::isInstanceDocument, doc);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsISupports> owner(do_QueryInterface(mElement));
NS_ENSURE_STATE(owner);
rv = doc->SetProperty(nsXFormsAtoms::instanceDocumentOwner, owner);
NS_ENSURE_SUCCESS(rv, rv);
}
return NS_OK;
}
NS_IMETHODIMP
nsXFormsInstanceElement::BackupOriginalDocument()
{
nsresult rv = NS_OK;
// This is called when xforms-ready is received by the model. By now we know
// that the instance document, whether external or inline, is loaded into
// mDocument. Get the root node, clone it, and insert it into our copy of
// the document. This is the magic behind getting xforms-reset to work.
nsCOMPtr<nsIDocument> origDoc(do_QueryInterface(mOriginalDocument));
if(mDocument && origDoc) {
// xf:instance elements in original document must not try to load anything.
rv = origDoc->SetProperty(nsXFormsAtoms::isInstanceDocument, origDoc);
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIDOMNode> newNode;
nsCOMPtr<nsIDOMElement> instanceRoot;
rv = mDocument->GetDocumentElement(getter_AddRefs(instanceRoot));
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(instanceRoot, NS_ERROR_FAILURE);
nsCOMPtr<nsIDOMNode> nodeReturn;
rv = instanceRoot->CloneNode(PR_TRUE, getter_AddRefs(newNode));
if(NS_SUCCEEDED(rv)) {
rv = mOriginalDocument->AppendChild(newNode, getter_AddRefs(nodeReturn));
NS_WARN_IF_FALSE(NS_SUCCEEDED(rv),
"failed to set up original instance document");
}
}
return rv;
}
NS_IMETHODIMP
nsXFormsInstanceElement::RestoreOriginalDocument()
{
nsresult rv = NS_OK;
// This is called when xforms-reset is received by the model. We assume
// that the backup of the instance document has been populated and is
// loaded into mOriginalDocument. Get the backup's root node, clone it, and
// insert it into the live copy of the instance document. This is the magic
// behind getting xforms-reset to work.
if(mDocument && mOriginalDocument) {
nsCOMPtr<nsIDOMNode> newNode, instanceRootNode, nodeReturn;
nsCOMPtr<nsIDOMElement> instanceRoot;
// first remove all the old stuff
rv = mDocument->GetDocumentElement(getter_AddRefs(instanceRoot));
if(NS_SUCCEEDED(rv)) {
if(instanceRoot) {
rv = mDocument->RemoveChild(instanceRoot, getter_AddRefs(nodeReturn));
NS_ENSURE_SUCCESS(rv, rv);
}
}
// now all of the garbage is out o' there! Put the original data back
// into mDocument
rv = mOriginalDocument->GetDocumentElement(getter_AddRefs(instanceRoot));
NS_ENSURE_SUCCESS(rv, rv);
NS_ENSURE_TRUE(instanceRoot, NS_ERROR_FAILURE);
instanceRootNode = do_QueryInterface(instanceRoot);
rv = instanceRootNode->CloneNode(PR_TRUE, getter_AddRefs(newNode));
if(NS_SUCCEEDED(rv)) {
rv = mDocument->AppendChild(newNode, getter_AddRefs(nodeReturn));
NS_WARN_IF_FALSE(NS_SUCCEEDED(rv),
"failed to restore original instance document");
}
}
return rv;
}
NS_IMETHODIMP
nsXFormsInstanceElement::GetElement(nsIDOMElement **aElement)
{
NS_IF_ADDREF(*aElement = mElement);
return NS_OK;
}
NS_IMETHODIMP
nsXFormsInstanceElement::WillChangeParent(nsIDOMElement *aNewParent)
{
if (!aNewParent) {
nsCOMPtr<nsIModelElementPrivate> model = GetModel();
if (model) {
model->RemoveInstanceElement(this);
}
}
return NS_OK;
}
NS_IMETHODIMP
nsXFormsInstanceElement::ParentChanged(nsIDOMElement *aNewParent)
{
nsCOMPtr<nsIModelElementPrivate> model = GetModel();
if (!model) return NS_OK;
if (mInitialized || !mElement) {
return NS_OK;
}
mInitialized = PR_TRUE;
model->AddInstanceElement(this);
// If model isn't loaded entirely (It means xforms-ready event hasn't been
// fired) then the instance will be initialized by model and will be backed up
// when xforms-ready event is fired.
PRBool isready;
model->GetIsReady(&isready);
if (!isready)
return NS_OK;
// If the model is loaded and ready then the instance is inserted dynamically.
// The instance should create instance document and back it up.
// Probably dynamic instances should be handled too when model isn't loaded
// entirely (for more information see a comment 29 of bug 320081
// https://bugzilla.mozilla.org/show_bug.cgi?id=320081#c29).
nsAutoString src;
mElement->GetAttribute(NS_LITERAL_STRING("src"), src);
if (!src.IsEmpty()) {
// XXX: external dynamic instances isn't handled (see a bug 325684
// https://bugzilla.mozilla.org/show_bug.cgi?id=325684)
return NS_OK;
}
// If we don't have a linked external instance, use our inline data.
nsresult rv = CloneInlineInstance();
if (NS_FAILED(rv))
return rv;
return BackupOriginalDocument();
}
NS_IMETHODIMP
nsXFormsInstanceElement::Initialize()
{
mElement->HasAttributeNS(NS_LITERAL_STRING(NS_NAMESPACE_MOZ_XFORMS_LAZY),
NS_LITERAL_STRING("lazy"), &mLazy);
if (mLazy) { // Lazy instance
return CreateInstanceDocument(NS_LITERAL_STRING("instanceData"));
}
// Normal instance
nsAutoString src;
mElement->GetAttribute(NS_LITERAL_STRING("src"), src);
if (src.IsEmpty()) {
return CloneInlineInstance();
}
LoadExternalInstance(src);
return NS_OK;
}
// private methods
nsresult
nsXFormsInstanceElement::CloneInlineInstance()
{
// Clear out our existing instance data
nsresult rv = CreateInstanceDocument(EmptyString());
if (NS_FAILED(rv))
return rv; // don't warn, we might just not be in the document yet
// look for our first child element (skip over text nodes, etc.)
nsCOMPtr<nsIDOMNode> child, temp;
mElement->GetFirstChild(getter_AddRefs(child));
while (child) {
PRUint16 nodeType;
child->GetNodeType(&nodeType);
if (nodeType == nsIDOMNode::ELEMENT_NODE)
break;
temp.swap(child);
temp->GetNextSibling(getter_AddRefs(child));
}
if (child) {
nsCOMPtr<nsIDOMNode> newNode;
rv = mDocument->ImportNode(child, PR_TRUE, getter_AddRefs(newNode));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIDOMNode> nodeReturn;
rv = mDocument->AppendChild(newNode, getter_AddRefs(nodeReturn));
NS_WARN_IF_FALSE(NS_SUCCEEDED(rv), "failed to append root instance node");
}
return rv;
}
void
nsXFormsInstanceElement::LoadExternalInstance(const nsAString &aSrc)
{
nsresult rv = NS_ERROR_FAILURE;
PRBool restart = PR_FALSE;
if (mChannel) {
// probably hit this condition because someone changed the value of our
// src attribute while we are already trying to load the previously
// specified document. We'll stop the current load effort and kick off the
// new attempt.
restart = PR_TRUE;
mChannel->Cancel(NS_BINDING_ABORTED);
mChannel = nsnull;
mListener = nsnull;
}
// Check whether we are an instance document ourselves
nsCOMPtr<nsIDOMDocument> domDoc;
mElement->GetOwnerDocument(getter_AddRefs(domDoc));
nsCOMPtr<nsIDocument> doc(do_QueryInterface(domDoc));
if (doc) {
if (doc->GetProperty(nsXFormsAtoms::isInstanceDocument)) {
/// Property exists, which means we are an instance document trying
/// to load an external instance document. We do not allow that.
const nsPromiseFlatString& flat = PromiseFlatString(aSrc);
const PRUnichar *strings[] = { flat.get() };
nsXFormsUtils::ReportError(NS_LITERAL_STRING("instanceInstanceLoad"),
strings, 1, mElement, mElement);
} else {
// Clear out our existing instance data
if (NS_SUCCEEDED(CreateInstanceDocument(EmptyString()))) {
nsCOMPtr<nsIDocument> newDoc = do_QueryInterface(mDocument);
nsCOMPtr<nsIURI> uri;
NS_NewURI(getter_AddRefs(uri), aSrc,
doc->GetDocumentCharacterSet().get(), doc->GetDocumentURI());
if (uri) {
if (nsXFormsUtils::CheckSameOrigin(doc, uri)) {
nsCOMPtr<nsILoadGroup> loadGroup;
loadGroup = doc->GetDocumentLoadGroup();
NS_WARN_IF_FALSE(loadGroup, "No load group!");
// Using the same load group as the main document and creating
// the channel with LOAD_NORMAL flag delays the dispatching of
// the 'load' event until all instance data documents have been
// loaded.
NS_NewChannel(getter_AddRefs(mChannel), uri, nsnull, loadGroup,
nsnull, nsIRequest::LOAD_NORMAL);
if (mChannel) {
rv = newDoc->StartDocumentLoad(kLoadAsData, mChannel, loadGroup,
nsnull, getter_AddRefs(mListener),
PR_TRUE);
if (NS_SUCCEEDED(rv)) {
mChannel->SetNotificationCallbacks(this);
rv = mChannel->AsyncOpen(this, nsnull);
}
}
} else {
nsXFormsUtils::ReportError(NS_LITERAL_STRING("instanceLoadOrigin"),
domDoc);
}
}
}
}
}
nsCOMPtr<nsIModelElementPrivate> model = GetModel();
if (model) {
// if this isn't the first time that this instance element has tried
// to load an external document, then we don't need to tell the model
// to wait again. It would screw up the counter it uses. But if this
// isn't a restart, then by golly, the model better wait for us!
if (!restart) {
model->InstanceLoadStarted();
}
if (NS_FAILED(rv)) {
model->InstanceLoadFinished(PR_FALSE);
}
}
}
nsresult
nsXFormsInstanceElement::CreateInstanceDocument(const nsAString &aQualifiedName)
{
nsCOMPtr<nsIDOMDocument> doc;
nsresult rv = mElement->GetOwnerDocument(getter_AddRefs(doc));
NS_ENSURE_SUCCESS(rv, rv);
if (!doc) // could be we just aren't inserted yet, so don't warn
return NS_ERROR_FAILURE;
nsCOMPtr<nsIDOMDOMImplementation> domImpl;
rv = doc->GetImplementation(getter_AddRefs(domImpl));
NS_ENSURE_SUCCESS(rv, rv);
nsCOMPtr<nsIDOMDocument> newDoc;
rv = domImpl->CreateDocument(EmptyString(), aQualifiedName, nsnull,
getter_AddRefs(newDoc));
NS_ENSURE_SUCCESS(rv, rv);
rv = SetInstanceDocument(newDoc);
NS_ENSURE_SUCCESS(rv, rv);
// I don't know if not being able to create a backup document is worth
// failing this function. Since it probably won't be used often, we'll
// let it slide. But it probably does mean that things are going south
// with the browser.
domImpl->CreateDocument(EmptyString(), aQualifiedName, nsnull,
getter_AddRefs(mOriginalDocument));
return rv;
}
already_AddRefed<nsIModelElementPrivate>
nsXFormsInstanceElement::GetModel()
{
if (!mElement)
{
NS_WARNING("The XTF wrapper element has been destroyed");
return nsnull;
}
nsCOMPtr<nsIDOMNode> parentNode;
mElement->GetParentNode(getter_AddRefs(parentNode));
nsIModelElementPrivate *model = nsnull;
if (parentNode)
CallQueryInterface(parentNode, &model);
return model;
}
nsresult
NS_NewXFormsInstanceElement(nsIXTFElement **aResult)
{
*aResult = new nsXFormsInstanceElement();
if (!*aResult)
return NS_ERROR_OUT_OF_MEMORY;
NS_ADDREF(*aResult);
return NS_OK;
}