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/*
* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
* Copyright (C) 2000 Frederik Holljen (frederik.holljen@hig.no)
* Copyright (C) 2001 Peter Kelly (pmk@post.com)
* Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
* Copyright (C) 2004, 2008 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include "third_party/blink/renderer/core/dom/node_iterator_base.h"
#include "third_party/blink/renderer/bindings/core/v8/v8_node_filter.h"
#include "third_party/blink/renderer/core/dom/node.h"
#include "third_party/blink/renderer/core/execution_context/execution_context.h"
#include "third_party/blink/renderer/core/frame/web_feature.h"
#include "third_party/blink/renderer/platform/bindings/exception_state.h"
#include "third_party/blink/renderer/platform/instrumentation/use_counter.h"
namespace blink {
NodeIteratorBase::NodeIteratorBase(Node* root_node,
unsigned what_to_show,
V8NodeFilter* node_filter)
: root_(root_node), what_to_show_(what_to_show), filter_(node_filter) {}
unsigned NodeIteratorBase::AcceptNode(Node* node,
ExceptionState& exception_state) {
// DOM 6. Traversal
// https://dom.spec.whatwg.org/#traversal
// Each NodeIterator and TreeWalker object has an associated active flag to
// avoid recursive invocations.
if (active_flag_) {
// 1. If the active flag is set, then throw an "InvalidStateError"
// DOMException.
exception_state.ThrowDOMException(DOMExceptionCode::kInvalidStateError,
"Filter function can't be recursive");
return V8NodeFilter::FILTER_REJECT;
}
// 2. Let n be node’s nodeType attribute value minus 1.
// 3. If the nth bit (where 0 is the least significant bit) of whatToShow is
// not set, then return FILTER_SKIP.
//
// The bit twiddling here is done to map DOM node types, which are given as
// integers from 1 through 14, to whatToShow bit masks.
if (!(((1 << (node->getNodeType() - 1)) & what_to_show_)))
return V8NodeFilter::FILTER_SKIP;
// 4. If filter is null, then return FILTER_ACCEPT.
if (!filter_)
return V8NodeFilter::FILTER_ACCEPT;
// 5. Set the active flag.
base::AutoReset<bool> set_active_flag(&active_flag_, true);
// 6. Let result be the return value of call a user object’s operation with
// filter, "acceptNode", and « node ». If this throws an exception, then unset
// the active flag and rethrow the exception.
v8::TryCatch try_catch(filter_->GetIsolate());
uint16_t result = 0;
if (!filter_->acceptNode(nullptr, node).To(&result)) {
exception_state.RethrowV8Exception(try_catch.Exception());
return 0;
}
UseCounter::Count(
ExecutionContext::From(filter_->CallbackRelevantScriptState()),
filter_->IsCallbackObjectCallableForNodeIteratorBase()
? WebFeature::kNodeFilterIsFunction
: WebFeature::kNodeFilterIsObject);
// 7. Unset the active flag.
// 8. Return result.
return result;
}
void NodeIteratorBase::Trace(Visitor* visitor) {
visitor->Trace(root_);
visitor->Trace(filter_);
}
} // namespace blink
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