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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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_HTMLFormElement_h
+#define mozilla_dom_HTMLFormElement_h
+
+#include "mozilla/AsyncEventDispatcher.h"
+#include "mozilla/Attributes.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/dom/BrowsingContext.h"
+#include "mozilla/dom/PopupBlocker.h"
+#include "mozilla/dom/RadioGroupManager.h"
+#include "nsCOMPtr.h"
+#include "nsIFormControl.h"
+#include "nsGenericHTMLElement.h"
+#include "nsIRadioGroupContainer.h"
+#include "nsIWeakReferenceUtils.h"
+#include "nsThreadUtils.h"
+#include "nsInterfaceHashtable.h"
+#include "nsRefPtrHashtable.h"
+#include "nsTHashMap.h"
+#include "js/friend/DOMProxy.h" // JS::ExpandoAndGeneration
+
+class nsIMutableArray;
+class nsIURI;
+
+namespace mozilla {
+class EventChainPostVisitor;
+class EventChainPreVisitor;
+namespace dom {
+class DialogFormSubmission;
+class HTMLFormControlsCollection;
+class HTMLFormSubmission;
+class HTMLImageElement;
+class FormData;
+
+class HTMLFormElement final : public nsGenericHTMLElement,
+ public nsIRadioGroupContainer,
+ RadioGroupManager {
+ friend class HTMLFormControlsCollection;
+
+ public:
+ NS_IMPL_FROMNODE_HTML_WITH_TAG(HTMLFormElement, form)
+
+ explicit HTMLFormElement(
+ already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo);
+
+ enum { FORM_CONTROL_LIST_HASHTABLE_LENGTH = 8 };
+
+ // nsISupports
+ NS_DECL_ISUPPORTS_INHERITED
+
+ int32_t IndexOfContent(nsIContent* aContent);
+ nsGenericHTMLFormElement* GetDefaultSubmitElement() const;
+
+ // nsIRadioGroupContainer
+ void SetCurrentRadioButton(const nsAString& aName,
+ HTMLInputElement* aRadio) override;
+ HTMLInputElement* GetCurrentRadioButton(const nsAString& aName) override;
+ NS_IMETHOD GetNextRadioButton(const nsAString& aName, const bool aPrevious,
+ HTMLInputElement* aFocusedRadio,
+ HTMLInputElement** aRadioOut) override;
+ NS_IMETHOD WalkRadioGroup(const nsAString& aName,
+ nsIRadioVisitor* aVisitor) override;
+ void AddToRadioGroup(const nsAString& aName,
+ HTMLInputElement* aRadio) override;
+ void RemoveFromRadioGroup(const nsAString& aName,
+ HTMLInputElement* aRadio) override;
+ virtual uint32_t GetRequiredRadioCount(const nsAString& aName) const override;
+ virtual void RadioRequiredWillChange(const nsAString& aName,
+ bool aRequiredAdded) override;
+ virtual bool GetValueMissingState(const nsAString& aName) const override;
+ virtual void SetValueMissingState(const nsAString& aName,
+ bool aValue) override;
+
+ virtual ElementState IntrinsicState() const override;
+
+ // EventTarget
+ virtual void AsyncEventRunning(AsyncEventDispatcher* aEvent) override;
+
+ // nsIContent
+ virtual bool ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
+ const nsAString& aValue,
+ nsIPrincipal* aMaybeScriptedPrincipal,
+ nsAttrValue& aResult) override;
+ void GetEventTargetParent(EventChainPreVisitor& aVisitor) override;
+ void WillHandleEvent(EventChainPostVisitor& aVisitor) override;
+ virtual nsresult PostHandleEvent(EventChainPostVisitor& aVisitor) override;
+
+ virtual nsresult BindToTree(BindContext&, nsINode& aParent) override;
+ virtual void UnbindFromTree(bool aNullParent = true) override;
+ virtual nsresult BeforeSetAttr(int32_t aNamespaceID, nsAtom* aName,
+ const nsAttrValueOrString* aValue,
+ bool aNotify) override;
+
+ /**
+ * Forget all information about the current submission (and the fact that we
+ * are currently submitting at all).
+ */
+ void ForgetCurrentSubmission();
+
+ virtual nsresult Clone(dom::NodeInfo*, nsINode** aResult) const override;
+
+ NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(HTMLFormElement,
+ nsGenericHTMLElement)
+
+ /**
+ * Remove an element from this form's list of elements
+ *
+ * @param aElement the element to remove
+ * @param aUpdateValidity If true, updates the form validity.
+ * @return NS_OK if the element was successfully removed.
+ */
+ nsresult RemoveElement(nsGenericHTMLFormElement* aElement,
+ bool aUpdateValidity);
+
+ /**
+ * Remove an element from the lookup table maintained by the form.
+ * We can't fold this method into RemoveElement() because when
+ * RemoveElement() is called it doesn't know if the element is
+ * removed because the id attribute has changed, or because the
+ * name attribute has changed.
+ *
+ * @param aElement the element to remove
+ * @param aName the name or id of the element to remove
+ * @return NS_OK if the element was successfully removed.
+ */
+ nsresult RemoveElementFromTable(nsGenericHTMLFormElement* aElement,
+ const nsAString& aName);
+
+ /**
+ * Add an element to end of this form's list of elements
+ *
+ * @param aElement the element to add
+ * @param aUpdateValidity If true, the form validity will be updated.
+ * @param aNotify If true, send DocumentObserver notifications as needed.
+ * @return NS_OK if the element was successfully added
+ */
+ nsresult AddElement(nsGenericHTMLFormElement* aElement, bool aUpdateValidity,
+ bool aNotify);
+
+ /**
+ * Add an element to the lookup table maintained by the form.
+ *
+ * We can't fold this method into AddElement() because when
+ * AddElement() is called, the form control has no
+ * attributes. The name or id attributes of the form control
+ * are used as a key into the table.
+ */
+ nsresult AddElementToTable(nsGenericHTMLFormElement* aChild,
+ const nsAString& aName);
+
+ /**
+ * Remove an image element from this form's list of image elements
+ *
+ * @param aElement the image element to remove
+ * @return NS_OK if the element was successfully removed.
+ */
+ nsresult RemoveImageElement(HTMLImageElement* aElement);
+
+ /**
+ * Remove an image element from the lookup table maintained by the form.
+ * We can't fold this method into RemoveImageElement() because when
+ * RemoveImageElement() is called it doesn't know if the element is
+ * removed because the id attribute has changed, or because the
+ * name attribute has changed.
+ *
+ * @param aElement the image element to remove
+ * @param aName the name or id of the element to remove
+ * @return NS_OK if the element was successfully removed.
+ */
+ nsresult RemoveImageElementFromTable(HTMLImageElement* aElement,
+ const nsAString& aName);
+ /**
+ * Add an image element to the end of this form's list of image elements
+ *
+ * @param aElement the element to add
+ * @return NS_OK if the element was successfully added
+ */
+ nsresult AddImageElement(HTMLImageElement* aElement);
+
+ /**
+ * Add an image element to the lookup table maintained by the form.
+ *
+ * We can't fold this method into AddImageElement() because when
+ * AddImageElement() is called, the image attributes can change.
+ * The name or id attributes of the image are used as a key into the table.
+ */
+ nsresult AddImageElementToTable(HTMLImageElement* aChild,
+ const nsAString& aName);
+
+ /**
+ * Returns true if implicit submission of this form is disabled. For more
+ * on implicit submission see:
+ *
+ * http://www.whatwg.org/specs/web-apps/current-work/multipage/association-of-controls-and-forms.html#implicit-submission
+ */
+ bool ImplicitSubmissionIsDisabled() const;
+
+ /**
+ * Check whether a given nsGenericHTMLFormElement is the last single line
+ * input control that is not disabled. aElement is expected to not be null.
+ */
+ bool IsLastActiveElement(const nsGenericHTMLFormElement* aElement) const;
+
+ /**
+ * Check whether a given nsGenericHTMLFormElement is the default submit
+ * element. This is different from just comparing to
+ * GetDefaultSubmitElement() in certain situations inside an update
+ * when GetDefaultSubmitElement() might not be up to date. aElement
+ * is expected to not be null.
+ */
+ bool IsDefaultSubmitElement(const nsGenericHTMLFormElement* aElement) const;
+
+ /**
+ * Flag the form to know that a button or image triggered scripted form
+ * submission. In that case the form will defer the submission until the
+ * script handler returns and the return value is known.
+ */
+ void OnSubmitClickBegin(Element* aOriginatingElement);
+ void OnSubmitClickEnd();
+
+ /**
+ * This method will update the form validity.
+ *
+ * This method has to be called by form elements whenever their validity state
+ * or status regarding constraint validation changes.
+ *
+ * @note This method isn't used for CheckValidity().
+ * @note If an element becomes barred from constraint validation, it has to be
+ * considered as valid.
+ *
+ * @param aElementValidityState the new validity state of the element
+ */
+ void UpdateValidity(bool aElementValidityState);
+
+ /**
+ * This method check the form validity and make invalid form elements send
+ * invalid event if needed.
+ *
+ * @return Whether the form is valid.
+ *
+ * @note Do not call this method if novalidate/formnovalidate is used.
+ * @note This method might disappear with bug 592124, hopefuly.
+ * @see
+ * https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#interactively-validate-the-constraints
+ */
+ bool CheckValidFormSubmission();
+
+ /**
+ * Contruct the entry list to get their data pumped into the FormData and
+ * fire a `formdata` event with the entry list in formData attribute.
+ * <https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#constructing-form-data-set>
+ *
+ * @param aFormData the form data object
+ */
+ // TODO: Convert this to MOZ_CAN_RUN_SCRIPT (bug 1415230)
+ MOZ_CAN_RUN_SCRIPT_BOUNDARY nsresult ConstructEntryList(FormData* aFormData);
+
+ /**
+ * Whether the submission of this form has been ever prevented because of
+ * being invalid.
+ *
+ * @return Whether the submission of this form has been prevented because of
+ * being invalid.
+ */
+ bool HasEverTriedInvalidSubmit() const { return mEverTriedInvalidSubmit; }
+
+ /**
+ * Implements form[name]. Returns form controls in this form with the correct
+ * value of the name attribute.
+ */
+ already_AddRefed<nsISupports> FindNamedItem(const nsAString& aName,
+ nsWrapperCache** aCache);
+
+ // WebIDL
+
+ void GetAcceptCharset(DOMString& aValue) {
+ GetHTMLAttr(nsGkAtoms::acceptcharset, aValue);
+ }
+
+ void SetAcceptCharset(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::acceptcharset, aValue, aRv);
+ }
+
+ void GetAction(nsString& aValue);
+ void SetAction(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::action, aValue, aRv);
+ }
+
+ void GetAutocomplete(nsAString& aValue);
+ void SetAutocomplete(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::autocomplete, aValue, aRv);
+ }
+
+ void GetEnctype(nsAString& aValue);
+ void SetEnctype(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::enctype, aValue, aRv);
+ }
+
+ void GetEncoding(nsAString& aValue) { GetEnctype(aValue); }
+ void SetEncoding(const nsAString& aValue, ErrorResult& aRv) {
+ SetEnctype(aValue, aRv);
+ }
+
+ void GetMethod(nsAString& aValue);
+ void SetMethod(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::method, aValue, aRv);
+ }
+
+ void GetName(DOMString& aValue) { GetHTMLAttr(nsGkAtoms::name, aValue); }
+
+ void SetName(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::name, aValue, aRv);
+ }
+
+ bool NoValidate() const { return GetBoolAttr(nsGkAtoms::novalidate); }
+
+ void SetNoValidate(bool aValue, ErrorResult& aRv) {
+ SetHTMLBoolAttr(nsGkAtoms::novalidate, aValue, aRv);
+ }
+
+ void GetTarget(DOMString& aValue) { GetHTMLAttr(nsGkAtoms::target, aValue); }
+
+ void SetTarget(const nsAString& aValue, ErrorResult& aRv) {
+ SetHTMLAttr(nsGkAtoms::target, aValue, aRv);
+ }
+
+ // it's only out-of-line because the class definition is not available in the
+ // header
+ nsIHTMLCollection* Elements();
+
+ int32_t Length();
+
+ /**
+ * Check whether submission can proceed for this form then fire submit event.
+ * This basically implements steps 1-6 (more or less) of
+ * <https://html.spec.whatwg.org/multipage/forms.html#concept-form-submit>.
+ * @param aSubmitter If not null, is the "submitter" from that algorithm.
+ * Therefore it must be a valid submit control.
+ */
+ MOZ_CAN_RUN_SCRIPT void MaybeSubmit(Element* aSubmitter);
+ MOZ_CAN_RUN_SCRIPT void MaybeReset(Element* aSubmitter);
+ void Submit(ErrorResult& aRv);
+
+ /**
+ * Requests to submit the form. Unlike submit(), this method includes
+ * interactive constraint validation and firing a submit event,
+ * either of which can cancel submission.
+ *
+ * @param aSubmitter The submitter argument can be used to point to a specific
+ * submit button.
+ * @param aRv An ErrorResult.
+ * @see
+ * https://html.spec.whatwg.org/multipage/forms.html#dom-form-requestsubmit
+ */
+ MOZ_CAN_RUN_SCRIPT void RequestSubmit(nsGenericHTMLElement* aSubmitter,
+ ErrorResult& aRv);
+
+ MOZ_CAN_RUN_SCRIPT void Reset();
+
+ bool CheckValidity() { return CheckFormValidity(nullptr); }
+
+ bool ReportValidity() { return CheckValidFormSubmission(); }
+
+ Element* IndexedGetter(uint32_t aIndex, bool& aFound);
+
+ already_AddRefed<nsISupports> NamedGetter(const nsAString& aName,
+ bool& aFound);
+
+ void GetSupportedNames(nsTArray<nsString>& aRetval);
+
+ static int32_t CompareFormControlPosition(Element* aElement1,
+ Element* aElement2,
+ const nsIContent* aForm);
+#ifdef DEBUG
+ static void AssertDocumentOrder(
+ const nsTArray<nsGenericHTMLFormElement*>& aControls, nsIContent* aForm);
+ static void AssertDocumentOrder(
+ const nsTArray<RefPtr<nsGenericHTMLFormElement>>& aControls,
+ nsIContent* aForm);
+#endif
+
+ JS::ExpandoAndGeneration mExpandoAndGeneration;
+
+ protected:
+ virtual JSObject* WrapNode(JSContext* aCx,
+ JS::Handle<JSObject*> aGivenProto) override;
+
+ void PostPasswordEvent();
+ void PostPossibleUsernameEvent();
+
+ RefPtr<AsyncEventDispatcher> mFormPasswordEventDispatcher;
+ RefPtr<AsyncEventDispatcher> mFormPossibleUsernameEventDispatcher;
+
+ class RemoveElementRunnable;
+ friend class RemoveElementRunnable;
+
+ class RemoveElementRunnable : public Runnable {
+ public:
+ explicit RemoveElementRunnable(HTMLFormElement* aForm)
+ : Runnable("dom::HTMLFormElement::RemoveElementRunnable"),
+ mForm(aForm) {}
+
+ NS_IMETHOD Run() override {
+ mForm->HandleDefaultSubmitRemoval();
+ return NS_OK;
+ }
+
+ private:
+ RefPtr<HTMLFormElement> mForm;
+ };
+
+ nsresult DoReset();
+
+ // Async callback to handle removal of our default submit
+ void HandleDefaultSubmitRemoval();
+
+ //
+ // Submit Helpers
+ //
+ //
+ /**
+ * Attempt to submit (submission might be deferred)
+ *
+ * @param aPresContext the presentation context
+ * @param aEvent the DOM event that was passed to us for the submit
+ */
+ nsresult DoSubmit(Event* aEvent = nullptr);
+
+ /**
+ * Prepare the submission object (called by DoSubmit)
+ *
+ * @param aFormSubmission the submission object
+ * @param aEvent the DOM event that was passed to us for the submit
+ */
+ nsresult BuildSubmission(HTMLFormSubmission** aFormSubmission, Event* aEvent);
+ /**
+ * Perform the submission (called by DoSubmit and FlushPendingSubmission)
+ *
+ * @param aFormSubmission the submission object
+ */
+ nsresult SubmitSubmission(HTMLFormSubmission* aFormSubmission);
+
+ /**
+ * Submit a form[method=dialog]
+ * @param aFormSubmission the submission object
+ */
+ nsresult SubmitDialog(DialogFormSubmission* aFormSubmission);
+
+ /**
+ * Notify any submit observers of the submit.
+ *
+ * @param aActionURL the URL being submitted to
+ * @param aCancelSubmit out param where submit observers can specify that the
+ * submit should be cancelled.
+ */
+ nsresult NotifySubmitObservers(nsIURI* aActionURL, bool* aCancelSubmit,
+ bool aEarlyNotify);
+
+ /**
+ * If this form submission is secure -> insecure, ask the user if they want
+ * to continue.
+ *
+ * @param aActionURL the URL being submitted to
+ * @param aCancelSubmit out param: will be true if the user wants to cancel
+ */
+ nsresult DoSecureToInsecureSubmitCheck(nsIURI* aActionURL,
+ bool* aCancelSubmit);
+
+ /**
+ * Find form controls in this form with the correct value in the name
+ * attribute.
+ */
+ already_AddRefed<nsISupports> DoResolveName(const nsAString& aName);
+
+ /**
+ * Check the form validity following this algorithm:
+ * https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#statically-validate-the-constraints
+ *
+ * @param aInvalidElements [out] parameter containing the list of unhandled
+ * invalid controls.
+ *
+ * @return Whether the form is currently valid.
+ */
+ bool CheckFormValidity(nsTArray<RefPtr<Element>>* aInvalidElements) const;
+
+ // Clear the mImageNameLookupTable and mImageElements.
+ void Clear();
+
+ // Insert a element into the past names map.
+ void AddToPastNamesMap(const nsAString& aName, nsISupports* aChild);
+
+ // Remove the given element from the past names map. The element must be an
+ // nsGenericHTMLFormElement or HTMLImageElement.
+ void RemoveElementFromPastNamesMap(Element* aElement);
+
+ nsresult AddElementToTableInternal(
+ nsInterfaceHashtable<nsStringHashKey, nsISupports>& aTable,
+ nsIContent* aChild, const nsAString& aName);
+
+ nsresult RemoveElementFromTableInternal(
+ nsInterfaceHashtable<nsStringHashKey, nsISupports>& aTable,
+ nsIContent* aChild, const nsAString& aName);
+
+ public:
+ /**
+ * Flush a possible pending submission. If there was a scripted submission
+ * triggered by a button or image, the submission was defered. This method
+ * forces the pending submission to be submitted. (happens when the handler
+ * returns false or there is an action/target change in the script)
+ */
+ void FlushPendingSubmission();
+
+ /**
+ * Get the full URL to submit to. Do not submit if the returned URL is null.
+ *
+ * @param aActionURL the full, unadulterated URL you'll be submitting to [OUT]
+ * @param aOriginatingElement the originating element of the form submission
+ * [IN]
+ */
+ nsresult GetActionURL(nsIURI** aActionURL, Element* aOriginatingElement);
+
+ // Returns a number for this form that is unique within its owner document.
+ // This is used by nsContentUtils::GenerateStateKey to identify form controls
+ // that are inserted into the document by the parser.
+ int32_t GetFormNumberForStateKey();
+
+ /**
+ * Called when we have been cloned and adopted, and the information of the
+ * node has been changed.
+ */
+ void NodeInfoChanged(Document* aOldDoc) override;
+
+ protected:
+ //
+ // Data members
+ //
+ /** The list of controls (form.elements as well as stuff not in elements) */
+ RefPtr<HTMLFormControlsCollection> mControls;
+
+ /** The pending submission object */
+ UniquePtr<HTMLFormSubmission> mPendingSubmission;
+
+ /** The target browsing context, if any. */
+ RefPtr<BrowsingContext> mTargetContext;
+ /** The load identifier for the pending request created for a
+ * submit, used to be able to block double submits. */
+ Maybe<uint64_t> mCurrentLoadId;
+
+ /** The default submit element -- WEAK */
+ nsGenericHTMLFormElement* mDefaultSubmitElement;
+
+ /** The first submit element in mElements -- WEAK */
+ nsGenericHTMLFormElement* mFirstSubmitInElements;
+
+ /** The first submit element in mNotInElements -- WEAK */
+ nsGenericHTMLFormElement* mFirstSubmitNotInElements;
+
+ // This array holds on to all HTMLImageElement(s).
+ // This is needed to properly clean up the bi-directional references
+ // (both weak and strong) between the form and its HTMLImageElements.
+
+ nsTArray<HTMLImageElement*> mImageElements; // Holds WEAK references
+
+ // A map from an ID or NAME attribute to the HTMLImageElement(s), this
+ // hash holds strong references either to the named HTMLImageElement, or
+ // to a list of named HTMLImageElement(s), in the case where this hash
+ // holds on to a list of named HTMLImageElement(s) the list has weak
+ // references to the HTMLImageElement.
+
+ nsInterfaceHashtable<nsStringHashKey, nsISupports> mImageNameLookupTable;
+
+ // A map from names to elements that were gotten by those names from this
+ // form in that past. See "past names map" in the HTML5 specification.
+
+ nsInterfaceHashtable<nsStringHashKey, nsISupports> mPastNameLookupTable;
+
+ /** Keep track of what the popup state was when the submit was initiated */
+ PopupBlocker::PopupControlState mSubmitPopupState;
+
+ /**
+ * Number of invalid and candidate for constraint validation elements in the
+ * form the last time UpdateValidity has been called.
+ */
+ int32_t mInvalidElementsCount;
+
+ // See GetFormNumberForStateKey.
+ int32_t mFormNumber;
+
+ /** Whether we are currently processing a submit event or not */
+ bool mGeneratingSubmit;
+ /** Whether we are currently processing a reset event or not */
+ bool mGeneratingReset;
+ /** Whether the submission is to be deferred in case a script triggers it */
+ bool mDeferSubmission;
+ /** Whether we notified NS_FORMSUBMIT_SUBJECT listeners already */
+ bool mNotifiedObservers;
+ /** If we notified the listeners early, what was the result? */
+ bool mNotifiedObserversResult;
+ /**
+ * Whether the submission of this form has been ever prevented because of
+ * being invalid.
+ */
+ bool mEverTriedInvalidSubmit;
+ /** Whether we are constructing entry list */
+ bool mIsConstructingEntryList;
+ /** Whether we are firing submission event */
+ bool mIsFiringSubmissionEvents;
+
+ private:
+ bool IsSubmitting() const;
+
+ NotNull<const Encoding*> GetSubmitEncoding();
+
+ /**
+ * Fire an event when the form is removed from the DOM tree. This is now only
+ * used by the password manager.
+ */
+ void MaybeFireFormRemoved();
+
+ ~HTMLFormElement();
+};
+
+} // namespace dom
+
+} // namespace mozilla
+
+#endif // mozilla_dom_HTMLFormElement_h