gecko-dev/dom/html/HTMLFormControlsCollection.cpp

/* -*- 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 "mozilla/dom/HTMLFormControlsCollection.h"

#include "mozilla/FlushType.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/HTMLFormControlsCollectionBinding.h"
#include "mozilla/dom/HTMLFormElement.h"
#include "nsGenericHTMLElement.h"  // nsGenericHTMLFormElement
#include "nsIDocument.h"
#include "nsIFormControl.h"
#include "RadioNodeList.h"
#include "jsfriendapi.h"

namespace mozilla {
namespace dom {

/* static */ bool HTMLFormControlsCollection::ShouldBeInElements(
    nsIFormControl* aFormControl) {
  // For backwards compatibility (with 4.x and IE) we must not add
  // <input type=image> elements to the list of form controls in a
  // form.

  switch (aFormControl->ControlType()) {
    case NS_FORM_BUTTON_BUTTON:
    case NS_FORM_BUTTON_RESET:
    case NS_FORM_BUTTON_SUBMIT:
    case NS_FORM_INPUT_BUTTON:
    case NS_FORM_INPUT_CHECKBOX:
    case NS_FORM_INPUT_COLOR:
    case NS_FORM_INPUT_EMAIL:
    case NS_FORM_INPUT_FILE:
    case NS_FORM_INPUT_HIDDEN:
    case NS_FORM_INPUT_RESET:
    case NS_FORM_INPUT_PASSWORD:
    case NS_FORM_INPUT_RADIO:
    case NS_FORM_INPUT_SEARCH:
    case NS_FORM_INPUT_SUBMIT:
    case NS_FORM_INPUT_TEXT:
    case NS_FORM_INPUT_TEL:
    case NS_FORM_INPUT_URL:
    case NS_FORM_INPUT_NUMBER:
    case NS_FORM_INPUT_RANGE:
    case NS_FORM_INPUT_DATE:
    case NS_FORM_INPUT_TIME:
    case NS_FORM_INPUT_MONTH:
    case NS_FORM_INPUT_WEEK:
    case NS_FORM_INPUT_DATETIME_LOCAL:
    case NS_FORM_SELECT:
    case NS_FORM_TEXTAREA:
    case NS_FORM_FIELDSET:
    case NS_FORM_OBJECT:
    case NS_FORM_OUTPUT:
      return true;
  }

  // These form control types are not supposed to end up in the
  // form.elements array
  //
  // NS_FORM_INPUT_IMAGE
  //
  // XXXbz maybe we should just check for that type here instead of the big
  // switch?

  return false;
}

HTMLFormControlsCollection::HTMLFormControlsCollection(HTMLFormElement* aForm)
    : mForm(aForm)
      // Initialize the elements list to have an initial capacity
      // of 8 to reduce allocations on small forms.
      ,
      mElements(8),
      mNameLookupTable(HTMLFormElement::FORM_CONTROL_LIST_HASHTABLE_LENGTH) {}

HTMLFormControlsCollection::~HTMLFormControlsCollection() {
  mForm = nullptr;
  Clear();
}

void HTMLFormControlsCollection::DropFormReference() {
  mForm = nullptr;
  Clear();
}

void HTMLFormControlsCollection::Clear() {
  // Null out childrens' pointer to me.  No refcounting here
  for (int32_t i = mElements.Length() - 1; i >= 0; i--) {
    mElements[i]->ClearForm(false, false);
  }
  mElements.Clear();

  for (int32_t i = mNotInElements.Length() - 1; i >= 0; i--) {
    mNotInElements[i]->ClearForm(false, false);
  }
  mNotInElements.Clear();

  mNameLookupTable.Clear();
}

void HTMLFormControlsCollection::FlushPendingNotifications() {
  if (mForm) {
    nsIDocument* doc = mForm->GetUncomposedDoc();
    if (doc) {
      doc->FlushPendingNotifications(FlushType::Content);
    }
  }
}

NS_IMPL_CYCLE_COLLECTION_CLASS(HTMLFormControlsCollection)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(HTMLFormControlsCollection)
  // Note: We intentionally don't set tmp->mForm to nullptr here, since doing
  // so may result in crashes because of inconsistent null-checking after the
  // object gets unlinked.
  tmp->Clear();
  NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
NS_IMPL_CYCLE_COLLECTION_UNLINK_END
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(HTMLFormControlsCollection)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mNameLookupTable)
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
NS_IMPL_CYCLE_COLLECTION_TRACE_BEGIN(HTMLFormControlsCollection)
  NS_IMPL_CYCLE_COLLECTION_TRACE_PRESERVED_WRAPPER
NS_IMPL_CYCLE_COLLECTION_TRACE_END

// XPConnect interface list for HTMLFormControlsCollection
NS_INTERFACE_TABLE_HEAD(HTMLFormControlsCollection)
  NS_WRAPPERCACHE_INTERFACE_TABLE_ENTRY
  NS_INTERFACE_TABLE(HTMLFormControlsCollection, nsIHTMLCollection)
  NS_INTERFACE_TABLE_TO_MAP_SEGUE_CYCLE_COLLECTION(HTMLFormControlsCollection)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(HTMLFormControlsCollection)
NS_IMPL_CYCLE_COLLECTING_RELEASE(HTMLFormControlsCollection)

// nsIHTMLCollection interface

uint32_t HTMLFormControlsCollection::Length() {
  FlushPendingNotifications();
  return mElements.Length();
}

nsISupports* HTMLFormControlsCollection::NamedItemInternal(
    const nsAString& aName, bool aFlushContent) {
  if (aFlushContent) {
    FlushPendingNotifications();
  }

  return mNameLookupTable.GetWeak(aName);
}

nsresult HTMLFormControlsCollection::AddElementToTable(
    nsGenericHTMLFormElement* aChild, const nsAString& aName) {
  if (!ShouldBeInElements(aChild)) {
    return NS_OK;
  }

  return mForm->AddElementToTableInternal(mNameLookupTable, aChild, aName);
}

nsresult HTMLFormControlsCollection::IndexOfControl(nsIFormControl* aControl,
                                                    int32_t* aIndex) {
  // Note -- not a DOM method; callers should handle flushing themselves

  NS_ENSURE_ARG_POINTER(aIndex);

  *aIndex = mElements.IndexOf(aControl);

  return NS_OK;
}

nsresult HTMLFormControlsCollection::RemoveElementFromTable(
    nsGenericHTMLFormElement* aChild, const nsAString& aName) {
  if (!ShouldBeInElements(aChild)) {
    return NS_OK;
  }

  return mForm->RemoveElementFromTableInternal(mNameLookupTable, aChild, aName);
}

nsresult HTMLFormControlsCollection::GetSortedControls(
    nsTArray<RefPtr<nsGenericHTMLFormElement>>& aControls) const {
#ifdef DEBUG
  HTMLFormElement::AssertDocumentOrder(mElements, mForm);
  HTMLFormElement::AssertDocumentOrder(mNotInElements, mForm);
#endif

  aControls.Clear();

  // Merge the elements list and the not in elements list. Both lists are
  // already sorted.
  uint32_t elementsLen = mElements.Length();
  uint32_t notInElementsLen = mNotInElements.Length();
  aControls.SetCapacity(elementsLen + notInElementsLen);

  uint32_t elementsIdx = 0;
  uint32_t notInElementsIdx = 0;

  while (elementsIdx < elementsLen || notInElementsIdx < notInElementsLen) {
    // Check whether we're done with mElements
    if (elementsIdx == elementsLen) {
      NS_ASSERTION(notInElementsIdx < notInElementsLen,
                   "Should have remaining not-in-elements");
      // Append the remaining mNotInElements elements
      if (!aControls.AppendElements(
              mNotInElements.Elements() + notInElementsIdx,
              notInElementsLen - notInElementsIdx)) {
        return NS_ERROR_OUT_OF_MEMORY;
      }
      break;
    }
    // Check whether we're done with mNotInElements
    if (notInElementsIdx == notInElementsLen) {
      NS_ASSERTION(elementsIdx < elementsLen,
                   "Should have remaining in-elements");
      // Append the remaining mElements elements
      if (!aControls.AppendElements(mElements.Elements() + elementsIdx,
                                    elementsLen - elementsIdx)) {
        return NS_ERROR_OUT_OF_MEMORY;
      }
      break;
    }
    // Both lists have elements left.
    NS_ASSERTION(mElements[elementsIdx] && mNotInElements[notInElementsIdx],
                 "Should have remaining elements");
    // Determine which of the two elements should be ordered
    // first and add it to the end of the list.
    nsGenericHTMLFormElement* elementToAdd;
    if (HTMLFormElement::CompareFormControlPosition(
            mElements[elementsIdx], mNotInElements[notInElementsIdx], mForm) <
        0) {
      elementToAdd = mElements[elementsIdx];
      ++elementsIdx;
    } else {
      elementToAdd = mNotInElements[notInElementsIdx];
      ++notInElementsIdx;
    }
    // Add the first element to the list.
    if (!aControls.AppendElement(elementToAdd)) {
      return NS_ERROR_OUT_OF_MEMORY;
    }
  }

  NS_ASSERTION(aControls.Length() == elementsLen + notInElementsLen,
               "Not all form controls were added to the sorted list");
#ifdef DEBUG
  HTMLFormElement::AssertDocumentOrder(aControls, mForm);
#endif

  return NS_OK;
}

Element* HTMLFormControlsCollection::GetElementAt(uint32_t aIndex) {
  FlushPendingNotifications();

  return mElements.SafeElementAt(aIndex, nullptr);
}

/* virtual */ nsINode* HTMLFormControlsCollection::GetParentObject() {
  return mForm;
}

/* virtual */ Element* HTMLFormControlsCollection::GetFirstNamedElement(
    const nsAString& aName, bool& aFound) {
  Nullable<OwningRadioNodeListOrElement> maybeResult;
  NamedGetter(aName, aFound, maybeResult);
  if (!aFound) {
    return nullptr;
  }
  MOZ_ASSERT(!maybeResult.IsNull());
  const OwningRadioNodeListOrElement& result = maybeResult.Value();
  if (result.IsElement()) {
    return result.GetAsElement().get();
  }
  if (result.IsRadioNodeList()) {
    RadioNodeList& nodelist = result.GetAsRadioNodeList();
    return nodelist.Item(0)->AsElement();
  }
  MOZ_ASSERT_UNREACHABLE("Should only have Elements and NodeLists here.");
  return nullptr;
}

void HTMLFormControlsCollection::NamedGetter(
    const nsAString& aName, bool& aFound,
    Nullable<OwningRadioNodeListOrElement>& aResult) {
  nsISupports* item = NamedItemInternal(aName, true);
  if (!item) {
    aFound = false;
    return;
  }
  aFound = true;
  if (nsCOMPtr<Element> element = do_QueryInterface(item)) {
    aResult.SetValue().SetAsElement() = element;
    return;
  }
  if (nsCOMPtr<RadioNodeList> nodelist = do_QueryInterface(item)) {
    aResult.SetValue().SetAsRadioNodeList() = nodelist;
    return;
  }
  MOZ_ASSERT_UNREACHABLE("Should only have Elements and NodeLists here.");
}

void HTMLFormControlsCollection::GetSupportedNames(nsTArray<nsString>& aNames) {
  FlushPendingNotifications();
  // Just enumerate mNameLookupTable.  This won't guarantee order, but
  // that's OK, because the HTML5 spec doesn't define an order for
  // this enumeration.
  for (auto iter = mNameLookupTable.Iter(); !iter.Done(); iter.Next()) {
    aNames.AppendElement(iter.Key());
  }
}

/* virtual */ JSObject* HTMLFormControlsCollection::WrapObject(
    JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
  return HTMLFormControlsCollection_Binding::Wrap(aCx, this, aGivenProto);
}

}  // namespace dom
}  // namespace mozilla