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webkit / WebKit / ea6a1ff9671bb166eba94387fe28817878d5867a / . / Source / WebCore / editing / TextIterator.cpp
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/*
* Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
* Copyright (C) 2005 Alexey Proskuryakov.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "config.h"
#include "TextIterator.h"
#include "Document.h"
#include "ExceptionCodePlaceholder.h"
#include "Font.h"
#include "Frame.h"
#include "HTMLElement.h"
#include "HTMLNames.h"
#include "HTMLTextFormControlElement.h"
#include "InlineTextBox.h"
#include "NodeTraversal.h"
#include "RenderImage.h"
#include "RenderTableCell.h"
#include "RenderTableRow.h"
#include "RenderTextControl.h"
#include "RenderTextFragment.h"
#include "ShadowRoot.h"
#include "TextBoundaries.h"
#include "TextBreakIterator.h"
#include "TextControlInnerElements.h"
#include "VisiblePosition.h"
#include "VisibleUnits.h"
#include "htmlediting.h"
#include <wtf/text/CString.h>
#include <wtf/unicode/CharacterNames.h>
#if USE(ICU_UNICODE) && !UCONFIG_NO_COLLATION
#include "TextBreakIteratorInternalICU.h"
#include <unicode/usearch.h>
#endif
using namespace WTF::Unicode;
namespace WebCore {
using namespace HTMLNames;
// Buffer that knows how to compare with a search target.
// Keeps enough of the previous text to be able to search in the future, but no more.
// Non-breaking spaces are always equal to normal spaces.
// Case folding is also done if the CaseInsensitive option is specified.
// Matches are further filtered if the AtWordStarts option is specified, although some
// matches inside a word are permitted if TreatMedialCapitalAsWordStart is specified as well.
class SearchBuffer {
WTF_MAKE_NONCOPYABLE(SearchBuffer);
public:
SearchBuffer(const String& target, FindOptions);
~SearchBuffer();
// Returns number of characters appended; guaranteed to be in the range [1, length].
size_t append(const UChar*, size_t length);
bool needsMoreContext() const;
void prependContext(const UChar*, size_t length);
void reachedBreak();
// Result is the size in characters of what was found.
// And <startOffset> is the number of characters back to the start of what was found.
size_t search(size_t& startOffset);
bool atBreak() const;
#if USE(ICU_UNICODE) && !UCONFIG_NO_COLLATION
private:
bool isBadMatch(const UChar*, size_t length) const;
bool isWordStartMatch(size_t start, size_t length) const;
String m_target;
FindOptions m_options;
Vector<UChar> m_buffer;
size_t m_overlap;
size_t m_prefixLength;
bool m_atBreak;
bool m_needsMoreContext;
bool m_targetRequiresKanaWorkaround;
Vector<UChar> m_normalizedTarget;
mutable Vector<UChar> m_normalizedMatch;
#else
private:
void append(UChar, bool isCharacterStart);
size_t length() const;
String m_target;
FindOptions m_options;
Vector<UChar> m_buffer;
Vector<bool> m_isCharacterStartBuffer;
bool m_isBufferFull;
size_t m_cursor;
#endif
};
// --------
static const unsigned bitsInWord = sizeof(unsigned) * 8;
static const unsigned bitInWordMask = bitsInWord - 1;
BitStack::BitStack()
: m_size(0)
{
}
BitStack::~BitStack()
{
}
void BitStack::push(bool bit)
{
unsigned index = m_size / bitsInWord;
unsigned shift = m_size & bitInWordMask;
if (!shift && index == m_words.size()) {
m_words.grow(index + 1);
m_words[index] = 0;
}
unsigned& word = m_words[index];
unsigned mask = 1U << shift;
if (bit)
word |= mask;
else
word &= ~mask;
++m_size;
}
void BitStack::pop()
{
if (m_size)
--m_size;
}
bool BitStack::top() const
{
if (!m_size)
return false;
unsigned shift = (m_size - 1) & bitInWordMask;
return m_words.last() & (1U << shift);
}
unsigned BitStack::size() const
{
return m_size;
}
// --------
#if !ASSERT_DISABLED
static unsigned depthCrossingShadowBoundaries(Node* node)
{
unsigned depth = 0;
for (Node* parent = node->parentOrShadowHostNode(); parent; parent = parent->parentOrShadowHostNode())
++depth;
return depth;
}
#endif
// This function is like Range::pastLastNode, except for the fact that it can climb up out of shadow trees.
static Node* nextInPreOrderCrossingShadowBoundaries(Node* rangeEndContainer, int rangeEndOffset)
{
if (!rangeEndContainer)
return 0;
if (rangeEndOffset >= 0 && !rangeEndContainer->offsetInCharacters()) {
if (Node* next = rangeEndContainer->childNode(rangeEndOffset))
return next;
}
for (Node* node = rangeEndContainer; node; node = node->parentOrShadowHostNode()) {
if (Node* next = node->nextSibling())
return next;
}
return 0;
}
// --------
static inline bool fullyClipsContents(Node* node)
{
RenderObject* renderer = node->renderer();
if (!renderer || !renderer->isBox() || !renderer->hasOverflowClip())
return false;
return toRenderBox(renderer)->size().isEmpty();
}
static inline bool ignoresContainerClip(Node* node)
{
RenderObject* renderer = node->renderer();
if (!renderer || renderer->isTextOrLineBreak())
return false;
return renderer->style().hasOutOfFlowPosition();
}
static void pushFullyClippedState(BitStack& stack, Node* node)
{
ASSERT(stack.size() == depthCrossingShadowBoundaries(node));
// Push true if this node full clips its contents, or if a parent already has fully
// clipped and this is not a node that ignores its container's clip.
stack.push(fullyClipsContents(node) || (stack.top() && !ignoresContainerClip(node)));
}
static void setUpFullyClippedStack(BitStack& stack, Node* node)
{
// Put the nodes in a vector so we can iterate in reverse order.
Vector<Node*, 100> ancestry;
for (Node* parent = node->parentOrShadowHostNode(); parent; parent = parent->parentOrShadowHostNode())
ancestry.append(parent);
// Call pushFullyClippedState on each node starting with the earliest ancestor.
size_t size = ancestry.size();
for (size_t i = 0; i < size; ++i)
pushFullyClippedState(stack, ancestry[size - i - 1]);
pushFullyClippedState(stack, node);
ASSERT(stack.size() == 1 + depthCrossingShadowBoundaries(node));
}
static bool isRendererReplacedElement(RenderObject* renderer)
{
if (!renderer)
return false;
if (renderer->isImage() || renderer->isWidget())
return true;
if (renderer->node() && renderer->node()->isElementNode()) {
Element* element = toElement(renderer->node());
if (element->isFormControlElement() || element->hasTagName(legendTag)
|| element->hasTagName(meterTag) || element->hasTagName(progressTag))
return true;
if (equalIgnoringCase(element->getAttribute(roleAttr), "img"))
return true;
}
return false;
}
// --------
TextIterator::TextIterator(const Range* r, TextIteratorBehavior behavior)
: m_startContainer(0)
, m_startOffset(0)
, m_endContainer(0)
, m_endOffset(0)
, m_positionNode(0)
, m_textCharacters(0)
, m_textLength(0)
, m_remainingTextBox(0)
, m_firstLetterText(0)
, m_sortedTextBoxesPosition(0)
, m_emitsCharactersBetweenAllVisiblePositions(behavior & TextIteratorEmitsCharactersBetweenAllVisiblePositions)
, m_entersTextControls(behavior & TextIteratorEntersTextControls)
, m_emitsTextWithoutTranscoding(behavior & TextIteratorEmitsTextsWithoutTranscoding)
, m_emitsOriginalText(behavior & TextIteratorEmitsOriginalText)
, m_handledFirstLetter(false)
, m_ignoresStyleVisibility(behavior & TextIteratorIgnoresStyleVisibility)
, m_emitsObjectReplacementCharacters(behavior & TextIteratorEmitsObjectReplacementCharacters)
, m_stopsOnFormControls(behavior & TextIteratorStopsOnFormControls)
, m_shouldStop(false)
, m_emitsImageAltText(behavior & TextIteratorEmitsImageAltText)
{
if (!r)
return;
r->ownerDocument().updateLayoutIgnorePendingStylesheets();
// get and validate the range endpoints
Node* startContainer = r->startContainer();
if (!startContainer)
return;
int startOffset = r->startOffset();
Node* endContainer = r->endContainer();
int endOffset = r->endOffset();
// Callers should be handing us well-formed ranges. If we discover that this isn't
// the case, we could consider changing this assertion to an early return.
ASSERT(r->boundaryPointsValid());
// remember range - this does not change
m_startContainer = startContainer;
m_startOffset = startOffset;
m_endContainer = endContainer;
m_endOffset = endOffset;
// set up the current node for processing
m_node = r->firstNode();
if (!m_node)
return;
setUpFullyClippedStack(m_fullyClippedStack, m_node);
m_offset = m_node == m_startContainer ? m_startOffset : 0;
m_handledNode = false;
m_handledChildren = false;
// calculate first out of bounds node
m_pastEndNode = nextInPreOrderCrossingShadowBoundaries(endContainer, endOffset);
// initialize node processing state
m_needsAnotherNewline = false;
m_textBox = 0;
// initialize record of previous node processing
m_hasEmitted = false;
m_lastTextNode = 0;
m_lastTextNodeEndedWithCollapsedSpace = false;
m_lastCharacter = 0;
#ifndef NDEBUG
// need this just because of the assert in advance()
m_positionNode = m_node;
#endif
// identify the first run
advance();
}
TextIterator::~TextIterator()
{
}
void TextIterator::advance()
{
if (m_shouldStop)
return;
// reset the run information
m_positionNode = 0;
m_textLength = 0;
// handle remembered node that needed a newline after the text node's newline
if (m_needsAnotherNewline) {
// Emit the extra newline, and position it *inside* m_node, after m_node's
// contents, in case it's a block, in the same way that we position the first
// newline. The range for the emitted newline should start where the line
// break begins.
// FIXME: It would be cleaner if we emitted two newlines during the last
// iteration, instead of using m_needsAnotherNewline.
Node* baseNode = m_node->lastChild() ? m_node->lastChild() : m_node;
emitCharacter('\n', baseNode->parentNode(), baseNode, 1, 1);
m_needsAnotherNewline = false;
return;
}
if (!m_textBox && m_remainingTextBox) {
m_textBox = m_remainingTextBox;
m_remainingTextBox = 0;
m_firstLetterText = 0;
m_offset = 0;
}
// handle remembered text box
if (m_textBox) {
handleTextBox();
if (m_positionNode)
return;
}
while (m_node && m_node != m_pastEndNode) {
if (!m_shouldStop && m_stopsOnFormControls && HTMLFormControlElement::enclosingFormControlElement(m_node))
m_shouldStop = true;
// if the range ends at offset 0 of an element, represent the
// position, but not the content, of that element e.g. if the
// node is a blockflow element, emit a newline that
// precedes the element
if (m_node == m_endContainer && m_endOffset == 0) {
representNodeOffsetZero();
m_node = 0;
return;
}
RenderObject* renderer = m_node->renderer();
if (!renderer) {
m_handledNode = true;
m_handledChildren = true;
} else {
// handle current node according to its type
if (!m_handledNode) {
if (renderer->isText() && m_node->nodeType() == Node::TEXT_NODE) // FIXME: What about CDATA_SECTION_NODE?
m_handledNode = handleTextNode();
else if (isRendererReplacedElement(renderer))
m_handledNode = handleReplacedElement();
else
m_handledNode = handleNonTextNode();
if (m_positionNode)
return;
}
}
// find a new current node to handle in depth-first manner,
// calling exitNode() as we come back thru a parent node
Node* next = m_handledChildren ? 0 : m_node->firstChild();
m_offset = 0;
if (!next) {
next = m_node->nextSibling();
if (!next) {
bool pastEnd = NodeTraversal::next(m_node) == m_pastEndNode;
Node* parentNode = m_node->parentOrShadowHostNode();
while (!next && parentNode) {
if ((pastEnd && parentNode == m_endContainer) || m_endContainer->isDescendantOf(parentNode))
return;
bool haveRenderer = m_node->renderer();
m_node = parentNode;
m_fullyClippedStack.pop();
parentNode = m_node->parentOrShadowHostNode();
if (haveRenderer)
exitNode();
if (m_positionNode) {
m_handledNode = true;
m_handledChildren = true;
return;
}
next = m_node->nextSibling();
}
}
m_fullyClippedStack.pop();
}
// set the new current node
m_node = next;
if (m_node)
pushFullyClippedState(m_fullyClippedStack, m_node);
m_handledNode = false;
m_handledChildren = false;
m_handledFirstLetter = false;
m_firstLetterText = 0;
// how would this ever be?
if (m_positionNode)
return;
}
}
UChar TextIterator::characterAt(unsigned index) const
{
ASSERT_WITH_SECURITY_IMPLICATION(index < static_cast<unsigned>(length()));
if (!(index < static_cast<unsigned>(length())))
return 0;
if (!m_textCharacters)
return string()[startOffset() + index];
return m_textCharacters[index];
}
void TextIterator::appendTextToStringBuilder(StringBuilder& builder) const
{
if (!m_textCharacters)
builder.append(string(), startOffset(), length());
else
builder.append(characters(), length());
}
bool TextIterator::handleTextNode()
{
if (m_fullyClippedStack.top() && !m_ignoresStyleVisibility)
return false;
RenderText* renderer = toRenderText(m_node->renderer());
m_lastTextNode = m_node;
String str = renderer->text();
// handle pre-formatted text
if (!renderer->style().collapseWhiteSpace()) {
int runStart = m_offset;
if (m_lastTextNodeEndedWithCollapsedSpace && hasVisibleTextNode(renderer)) {
emitCharacter(' ', m_node, 0, runStart, runStart);
return false;
}
if (!m_handledFirstLetter && renderer->isTextFragment() && !m_offset) {
handleTextNodeFirstLetter(static_cast<RenderTextFragment*>(renderer));
if (m_firstLetterText) {
String firstLetter = m_firstLetterText->text();
emitText(m_node, m_firstLetterText, m_offset, m_offset + firstLetter.length());
m_firstLetterText = 0;
m_textBox = 0;
return false;
}
}
if (renderer->style().visibility() != VISIBLE && !m_ignoresStyleVisibility)
return false;
int strLength = str.length();
int end = (m_node == m_endContainer) ? m_endOffset : INT_MAX;
int runEnd = std::min(strLength, end);
if (runStart >= runEnd)
return true;
emitText(m_node, runStart, runEnd);
return true;
}
if (renderer->simpleLineLayout()) {
if (renderer->style().visibility() != VISIBLE && !m_ignoresStyleVisibility)
return true;
// This code aims to produce same results as handleTextBox() below so test results don't change. It does not make much logical sense.
unsigned runEnd = m_offset;
unsigned runStart = m_offset;
while (runEnd < str.length() && (isCollapsibleWhitespace(str[runEnd]) || str[runEnd] == '\t'))
++runEnd;
bool addSpaceForPrevious = m_lastTextNodeEndedWithCollapsedSpace && m_lastCharacter && !isCollapsibleWhitespace(m_lastCharacter);
if (runEnd > runStart || addSpaceForPrevious) {
if (runEnd == str.length()) {
m_lastTextNodeEndedWithCollapsedSpace = true;
return true;
}
bool addSpaceForCurrent = runStart || (m_lastCharacter && !isCollapsibleWhitespace(m_lastCharacter));
if (addSpaceForCurrent || addSpaceForPrevious) {
emitCharacter(' ', m_node, 0, runStart, runEnd);
m_offset = runEnd;
return false;
}
runStart = runEnd;
}
while (runEnd < str.length() && !isCollapsibleWhitespace(str[runEnd]))
++runEnd;
if (runStart < str.length())
emitText(m_node, renderer, runStart, runEnd);
m_offset = runEnd;
return runEnd == str.length();
}
if (renderer->firstTextBox())
m_textBox = renderer->firstTextBox();
bool shouldHandleFirstLetter = !m_handledFirstLetter && renderer->isTextFragment() && !m_offset;
if (shouldHandleFirstLetter)
handleTextNodeFirstLetter(static_cast<RenderTextFragment*>(renderer));
if (!renderer->firstTextBox() && str.length() > 0 && !shouldHandleFirstLetter) {
if (renderer->style().visibility() != VISIBLE && !m_ignoresStyleVisibility)
return false;
m_lastTextNodeEndedWithCollapsedSpace = true; // entire block is collapsed space
return true;
}
if (m_firstLetterText)
renderer = m_firstLetterText;
// Used when text boxes are out of order (Hebrew/Arabic w/ embeded LTR text)
if (renderer->containsReversedText()) {
m_sortedTextBoxes.clear();
for (InlineTextBox* textBox = renderer->firstTextBox(); textBox; textBox = textBox->nextTextBox()) {
m_sortedTextBoxes.append(textBox);
}
std::sort(m_sortedTextBoxes.begin(), m_sortedTextBoxes.end(), InlineTextBox::compareByStart);
m_sortedTextBoxesPosition = 0;
m_textBox = m_sortedTextBoxes.isEmpty() ? 0 : m_sortedTextBoxes[0];
}
handleTextBox();
return true;
}
void TextIterator::handleTextBox()
{
RenderText* renderer = m_firstLetterText ? m_firstLetterText : toRenderText(m_node->renderer());
if (renderer->style().visibility() != VISIBLE && !m_ignoresStyleVisibility) {
m_textBox = 0;
return;
}
String str = renderer->text();
unsigned start = m_offset;
unsigned end = (m_node == m_endContainer) ? static_cast<unsigned>(m_endOffset) : UINT_MAX;
while (m_textBox) {
unsigned textBoxStart = m_textBox->start();
unsigned runStart = std::max(textBoxStart, start);
// Check for collapsed space at the start of this run.
InlineTextBox* firstTextBox = renderer->containsReversedText() ? (m_sortedTextBoxes.isEmpty() ? 0 : m_sortedTextBoxes[0]) : renderer->firstTextBox();
bool needSpace = m_lastTextNodeEndedWithCollapsedSpace
|| (m_textBox == firstTextBox && textBoxStart == runStart && runStart > 0);
if (needSpace && !isCollapsibleWhitespace(m_lastCharacter) && m_lastCharacter) {
if (m_lastTextNode == m_node && runStart > 0 && str[runStart - 1] == ' ') {
unsigned spaceRunStart = runStart - 1;
while (spaceRunStart > 0 && str[spaceRunStart - 1] == ' ')
--spaceRunStart;
emitText(m_node, renderer, spaceRunStart, spaceRunStart + 1);
} else
emitCharacter(' ', m_node, 0, runStart, runStart);
return;
}
unsigned textBoxEnd = textBoxStart + m_textBox->len();
unsigned runEnd = std::min(textBoxEnd, end);
// Determine what the next text box will be, but don't advance yet
InlineTextBox* nextTextBox = 0;
if (renderer->containsReversedText()) {
if (m_sortedTextBoxesPosition + 1 < m_sortedTextBoxes.size())
nextTextBox = m_sortedTextBoxes[m_sortedTextBoxesPosition + 1];
} else
nextTextBox = m_textBox->nextTextBox();
ASSERT(!nextTextBox || &nextTextBox->renderer() == renderer);
if (runStart < runEnd) {
// Handle either a single newline character (which becomes a space),
// or a run of characters that does not include a newline.
// This effectively translates newlines to spaces without copying the text.
if (str[runStart] == '\n') {
emitCharacter(' ', m_node, 0, runStart, runStart + 1);
m_offset = runStart + 1;
} else {
size_t subrunEnd = str.find('\n', runStart);
if (subrunEnd == notFound || subrunEnd > runEnd)
subrunEnd = runEnd;
m_offset = subrunEnd;
emitText(m_node, renderer, runStart, subrunEnd);
}
// If we are doing a subrun that doesn't go to the end of the text box,
// come back again to finish handling this text box; don't advance to the next one.
if (static_cast<unsigned>(m_positionEndOffset) < textBoxEnd)
return;
// Advance and return
unsigned nextRunStart = nextTextBox ? nextTextBox->start() : str.length();
if (nextRunStart > runEnd)
m_lastTextNodeEndedWithCollapsedSpace = true; // collapsed space between runs or at the end
m_textBox = nextTextBox;
if (renderer->containsReversedText())
++m_sortedTextBoxesPosition;
return;
}
// Advance and continue
m_textBox = nextTextBox;
if (renderer->containsReversedText())
++m_sortedTextBoxesPosition;
}
if (!m_textBox && m_remainingTextBox) {
m_textBox = m_remainingTextBox;
m_remainingTextBox = 0;
m_firstLetterText = 0;
m_offset = 0;
handleTextBox();
}
}
static inline RenderText* firstRenderTextInFirstLetter(RenderObject* firstLetter)
{
if (!firstLetter)
return 0;
// FIXME: Should this check descendent objects?
for (RenderObject* current = firstLetter->firstChildSlow(); current; current = current->nextSibling()) {
if (current->isText())
return toRenderText(current);
}
return 0;
}
void TextIterator::handleTextNodeFirstLetter(RenderTextFragment* renderer)
{
if (renderer->firstLetter()) {
RenderObject* r = renderer->firstLetter();
if (r->style().visibility() != VISIBLE && !m_ignoresStyleVisibility)
return;
if (RenderText* firstLetter = firstRenderTextInFirstLetter(r)) {
m_handledFirstLetter = true;
m_remainingTextBox = m_textBox;
m_textBox = firstLetter->firstTextBox();
m_sortedTextBoxes.clear();
m_firstLetterText = firstLetter;
}
}
m_handledFirstLetter = true;
}
bool TextIterator::handleReplacedElement()
{
if (m_fullyClippedStack.top())
return false;
RenderObject* renderer = m_node->renderer();
if (renderer->style().visibility() != VISIBLE && !m_ignoresStyleVisibility)
return false;
if (m_lastTextNodeEndedWithCollapsedSpace) {
emitCharacter(' ', m_lastTextNode->parentNode(), m_lastTextNode, 1, 1);
return false;
}
if (m_entersTextControls && renderer->isTextControl()) {
if (TextControlInnerTextElement* innerTextElement = toRenderTextControl(renderer)->textFormControlElement().innerTextElement()) {
m_node = innerTextElement->containingShadowRoot();
pushFullyClippedState(m_fullyClippedStack, m_node);
m_offset = 0;
return false;
}
}
m_hasEmitted = true;
if (m_emitsObjectReplacementCharacters && renderer && renderer->isReplaced()) {
emitCharacter(objectReplacementCharacter, m_node->parentNode(), m_node, 0, 1);
return true;
}
if (m_emitsCharactersBetweenAllVisiblePositions) {
// We want replaced elements to behave like punctuation for boundary
// finding, and to simply take up space for the selection preservation
// code in moveParagraphs, so we use a comma.
emitCharacter(',', m_node->parentNode(), m_node, 0, 1);
return true;
}
m_positionNode = m_node->parentNode();
m_positionOffsetBaseNode = m_node;
m_positionStartOffset = 0;
m_positionEndOffset = 1;
m_textCharacters = 0;
if (m_emitsImageAltText && renderer->isImage() && renderer->isRenderImage()) {
m_text = toRenderImage(renderer)->altText();
if (!m_text.isEmpty()) {
m_textLength = m_text.length();
m_lastCharacter = m_text[m_textLength - 1];
return true;
}
}
m_textLength = 0;
m_lastCharacter = 0;
return true;
}
bool TextIterator::hasVisibleTextNode(RenderText* renderer)
{
if (renderer->style().visibility() == VISIBLE)
return true;
if (renderer->isTextFragment()) {
RenderTextFragment* fragment = static_cast<RenderTextFragment*>(renderer);
if (fragment->firstLetter() && fragment->firstLetter()->style().visibility() == VISIBLE)
return true;
}
return false;
}
static bool shouldEmitTabBeforeNode(Node* node)
{
RenderObject* r = node->renderer();
// Table cells are delimited by tabs.
if (!r || !isTableCell(node))
return false;
// Want a tab before every cell other than the first one
RenderTableCell* rc = toRenderTableCell(r);
RenderTable* t = rc->table();
return t && (t->cellBefore(rc) || t->cellAbove(rc));
}
static bool shouldEmitNewlineForNode(Node* node, bool emitsOriginalText)
{
RenderObject* renderer = node->renderer();
if (renderer ? !renderer->isBR() : !node->hasTagName(brTag))
return false;
return emitsOriginalText || !(node->isInShadowTree() && node->shadowHost()->toInputElement());
}
static bool shouldEmitNewlinesBeforeAndAfterNode(Node* node)
{
// Block flow (versus inline flow) is represented by having
// a newline both before and after the element.
RenderObject* r = node->renderer();
if (!r) {
return (node->hasTagName(blockquoteTag)
|| node->hasTagName(ddTag)
|| node->hasTagName(divTag)
|| node->hasTagName(dlTag)
|| node->hasTagName(dtTag)
|| node->hasTagName(h1Tag)
|| node->hasTagName(h2Tag)
|| node->hasTagName(h3Tag)
|| node->hasTagName(h4Tag)
|| node->hasTagName(h5Tag)
|| node->hasTagName(h6Tag)
|| node->hasTagName(hrTag)
|| node->hasTagName(liTag)
|| node->hasTagName(listingTag)
|| node->hasTagName(olTag)
|| node->hasTagName(pTag)
|| node->hasTagName(preTag)
|| node->hasTagName(trTag)
|| node->hasTagName(ulTag));
}
// Need to make an exception for table cells, because they are blocks, but we
// want them tab-delimited rather than having newlines before and after.
if (isTableCell(node))
return false;
// Need to make an exception for table row elements, because they are neither
// "inline" or "RenderBlock", but we want newlines for them.
if (r->isTableRow()) {
RenderTable* t = toRenderTableRow(r)->table();
if (t && !t->isInline())
return true;
}
return !r->isInline() && r->isRenderBlock()
&& !r->isFloatingOrOutOfFlowPositioned() && !r->isBody() && !r->isRubyText();
}
static bool shouldEmitNewlineAfterNode(Node* node)
{
// FIXME: It should be better but slower to create a VisiblePosition here.
if (!shouldEmitNewlinesBeforeAndAfterNode(node))
return false;
// Check if this is the very last renderer in the document.
// If so, then we should not emit a newline.
while ((node = NodeTraversal::nextSkippingChildren(node)))
if (node->renderer())
return true;
return false;
}
static bool shouldEmitNewlineBeforeNode(Node* node)
{
return shouldEmitNewlinesBeforeAndAfterNode(node);
}
static bool shouldEmitExtraNewlineForNode(Node* node)
{
// When there is a significant collapsed bottom margin, emit an extra
// newline for a more realistic result. We end up getting the right
// result even without margin collapsing. For example: <div><p>text</p></div>
// will work right even if both the <div> and the <p> have bottom margins.
RenderObject* r = node->renderer();
if (!r || !r->isBox())
return false;
// NOTE: We only do this for a select set of nodes, and fwiw WinIE appears
// not to do this at all
if (node->hasTagName(h1Tag)
|| node->hasTagName(h2Tag)
|| node->hasTagName(h3Tag)
|| node->hasTagName(h4Tag)
|| node->hasTagName(h5Tag)
|| node->hasTagName(h6Tag)
|| node->hasTagName(pTag)) {
int bottomMargin = toRenderBox(r)->collapsedMarginAfter();
int fontSize = toRenderBox(r)->style().fontDescription().computedPixelSize();
if (bottomMargin * 2 >= fontSize)
return true;
}
return false;
}
static int collapsedSpaceLength(RenderText* renderer, int textEnd)
{
const UChar* characters = renderer->text()->characters();
int length = renderer->text()->length();
for (int i = textEnd; i < length; ++i) {
if (!renderer->style().isCollapsibleWhiteSpace(characters[i]))
return i - textEnd;
}
return length - textEnd;
}
static int maxOffsetIncludingCollapsedSpaces(Node* node)
{
int offset = caretMaxOffset(node);
if (node->renderer() && node->renderer()->isText())
offset += collapsedSpaceLength(toRenderText(node->renderer()), offset);
return offset;
}
// Whether or not we should emit a character as we enter m_node (if it's a container) or as we hit it (if it's atomic).
bool TextIterator::shouldRepresentNodeOffsetZero()
{
if (m_emitsCharactersBetweenAllVisiblePositions && m_node->renderer() && m_node->renderer()->isTable())
return true;
// Leave element positioned flush with start of a paragraph
// (e.g. do not insert tab before a table cell at the start of a paragraph)
if (m_lastCharacter == '\n')
return false;
// Otherwise, show the position if we have emitted any characters
if (m_hasEmitted)
return true;
// We've not emitted anything yet. Generally, there is no need for any positioning then.
// The only exception is when the element is visually not in the same line as
// the start of the range (e.g. the range starts at the end of the previous paragraph).
// NOTE: Creating VisiblePositions and comparing them is relatively expensive, so we
// make quicker checks to possibly avoid that. Another check that we could make is
// is whether the inline vs block flow changed since the previous visible element.
// I think we're already in a special enough case that that won't be needed, tho.
// No character needed if this is the first node in the range.
if (m_node == m_startContainer)
return false;
// If we are outside the start container's subtree, assume we need to emit.
// FIXME: m_startContainer could be an inline block
if (!m_node->isDescendantOf(m_startContainer))
return true;
// If we started as m_startContainer offset 0 and the current node is a descendant of
// the start container, we already had enough context to correctly decide whether to
// emit after a preceding block. We chose not to emit (m_hasEmitted is false),
// so don't second guess that now.
// NOTE: Is this really correct when m_node is not a leftmost descendant? Probably
// immaterial since we likely would have already emitted something by now.
if (m_startOffset == 0)
return false;
// If this node is unrendered or invisible the VisiblePosition checks below won't have much meaning.
// Additionally, if the range we are iterating over contains huge sections of unrendered content,
// we would create VisiblePositions on every call to this function without this check.
if (!m_node->renderer() || m_node->renderer()->style().visibility() != VISIBLE
|| (m_node->renderer()->isRenderBlockFlow() && !toRenderBlock(m_node->renderer())->height() && !m_node->hasTagName(bodyTag)))
return false;
// The startPos.isNotNull() check is needed because the start could be before the body,
// and in that case we'll get null. We don't want to put in newlines at the start in that case.
// The currPos.isNotNull() check is needed because positions in non-HTML content
// (like SVG) do not have visible positions, and we don't want to emit for them either.
VisiblePosition startPos = VisiblePosition(Position(m_startContainer, m_startOffset, Position::PositionIsOffsetInAnchor), DOWNSTREAM);
VisiblePosition currPos = VisiblePosition(positionBeforeNode(m_node), DOWNSTREAM);
return startPos.isNotNull() && currPos.isNotNull() && !inSameLine(startPos, currPos);
}
bool TextIterator::shouldEmitSpaceBeforeAndAfterNode(Node* node)
{
return node->renderer() && node->renderer()->isTable() && (node->renderer()->isInline() || m_emitsCharactersBetweenAllVisiblePositions);
}
void TextIterator::representNodeOffsetZero()
{
// Emit a character to show the positioning of m_node.
// When we haven't been emitting any characters, shouldRepresentNodeOffsetZero() can
// create VisiblePositions, which is expensive. So, we perform the inexpensive checks
// on m_node to see if it necessitates emitting a character first and will early return
// before encountering shouldRepresentNodeOffsetZero()s worse case behavior.
if (shouldEmitTabBeforeNode(m_node)) {
if (shouldRepresentNodeOffsetZero())
emitCharacter('\t', m_node->parentNode(), m_node, 0, 0);
} else if (shouldEmitNewlineBeforeNode(m_node)) {
if (shouldRepresentNodeOffsetZero())
emitCharacter('\n', m_node->parentNode(), m_node, 0, 0);
} else if (shouldEmitSpaceBeforeAndAfterNode(m_node)) {
if (shouldRepresentNodeOffsetZero())
emitCharacter(' ', m_node->parentNode(), m_node, 0, 0);
}
}
bool TextIterator::handleNonTextNode()
{
if (shouldEmitNewlineForNode(m_node, m_emitsOriginalText))
emitCharacter('\n', m_node->parentNode(), m_node, 0, 1);
else if (m_emitsCharactersBetweenAllVisiblePositions && m_node->renderer() && m_node->renderer()->isHR())
emitCharacter(' ', m_node->parentNode(), m_node, 0, 1);
else
representNodeOffsetZero();
return true;
}
void TextIterator::exitNode()
{
// prevent emitting a newline when exiting a collapsed block at beginning of the range
// FIXME: !m_hasEmitted does not necessarily mean there was a collapsed block... it could
// have been an hr (e.g.). Also, a collapsed block could have height (e.g. a table) and
// therefore look like a blank line.
if (!m_hasEmitted)
return;
// Emit with a position *inside* m_node, after m_node's contents, in
// case it is a block, because the run should start where the
// emitted character is positioned visually.
Node* baseNode = m_node->lastChild() ? m_node->lastChild() : m_node;
// FIXME: This shouldn't require the m_lastTextNode to be true, but we can't change that without making
// the logic in _web_attributedStringFromRange match. We'll get that for free when we switch to use
// TextIterator in _web_attributedStringFromRange.
// See <rdar://problem/5428427> for an example of how this mismatch will cause problems.
if (m_lastTextNode && shouldEmitNewlineAfterNode(m_node)) {
// use extra newline to represent margin bottom, as needed
bool addNewline = shouldEmitExtraNewlineForNode(m_node);
// FIXME: We need to emit a '\n' as we leave an empty block(s) that
// contain a VisiblePosition when doing selection preservation.
if (m_lastCharacter != '\n') {
// insert a newline with a position following this block's contents.
emitCharacter('\n', baseNode->parentNode(), baseNode, 1, 1);
// remember whether to later add a newline for the current node
ASSERT(!m_needsAnotherNewline);
m_needsAnotherNewline = addNewline;
} else if (addNewline)
// insert a newline with a position following this block's contents.
emitCharacter('\n', baseNode->parentNode(), baseNode, 1, 1);
}
// If nothing was emitted, see if we need to emit a space.
if (!m_positionNode && shouldEmitSpaceBeforeAndAfterNode(m_node))
emitCharacter(' ', baseNode->parentNode(), baseNode, 1, 1);
}
void TextIterator::emitCharacter(UChar c, Node* textNode, Node* offsetBaseNode, int textStartOffset, int textEndOffset)
{
m_hasEmitted = true;
// remember information with which to construct the TextIterator::range()
// NOTE: textNode is often not a text node, so the range will specify child nodes of positionNode
m_positionNode = textNode;
m_positionOffsetBaseNode = offsetBaseNode;
m_positionStartOffset = textStartOffset;
m_positionEndOffset = textEndOffset;
// remember information with which to construct the TextIterator::characters() and length()
m_singleCharacterBuffer = c;
m_textCharacters = &m_singleCharacterBuffer;
m_textLength = 1;
// remember some iteration state
m_lastTextNodeEndedWithCollapsedSpace = false;
m_lastCharacter = c;
}
void TextIterator::emitText(Node* textNode, RenderObject* renderObject, int textStartOffset, int textEndOffset)
{
RenderText* renderer = toRenderText(renderObject);
m_text = m_emitsOriginalText ? renderer->originalText() : (m_emitsTextWithoutTranscoding ? renderer->textWithoutConvertingBackslashToYenSymbol() : renderer->text());
ASSERT(!m_text.isEmpty());
ASSERT(0 <= textStartOffset && textStartOffset < static_cast<int>(m_text.length()));
ASSERT(0 <= textEndOffset && textEndOffset <= static_cast<int>(m_text.length()));
ASSERT(textStartOffset <= textEndOffset);
m_positionNode = textNode;
m_positionOffsetBaseNode = 0;
m_positionStartOffset = textStartOffset;
m_positionEndOffset = textEndOffset;
m_textCharacters = 0;
m_textLength = textEndOffset - textStartOffset;
m_lastCharacter = m_text[textEndOffset - 1];
m_lastTextNodeEndedWithCollapsedSpace = false;
m_hasEmitted = true;
}
void TextIterator::emitText(Node* textNode, int textStartOffset, int textEndOffset)
{
emitText(textNode, m_node->renderer(), textStartOffset, textEndOffset);
}
PassRefPtr<Range> TextIterator::range() const
{
// use the current run information, if we have it
if (m_positionNode) {
if (m_positionOffsetBaseNode) {
int index = m_positionOffsetBaseNode->nodeIndex();
m_positionStartOffset += index;
m_positionEndOffset += index;
m_positionOffsetBaseNode = 0;
}
return Range::create(m_positionNode->document(), m_positionNode, m_positionStartOffset, m_positionNode, m_positionEndOffset);
}
// otherwise, return the end of the overall range we were given
if (m_endContainer)
return Range::create(m_endContainer->document(), m_endContainer, m_endOffset, m_endContainer, m_endOffset);
return 0;
}
Node* TextIterator::node() const
{
RefPtr<Range> textRange = range();
if (!textRange)
return 0;
Node* node = textRange->startContainer();
if (!node)
return 0;
if (node->offsetInCharacters())
return node;
return node->childNode(textRange->startOffset());
}
// --------
SimplifiedBackwardsTextIterator::SimplifiedBackwardsTextIterator(const Range* r, TextIteratorBehavior behavior)
: m_node(0)
, m_offset(0)
, m_handledNode(false)
, m_handledChildren(false)
, m_startNode(0)
, m_startOffset(0)
, m_endNode(0)
, m_endOffset(0)
, m_positionNode(0)
, m_positionStartOffset(0)
, m_positionEndOffset(0)
, m_textCharacters(0)
, m_textLength(0)
, m_lastTextNode(0)
, m_lastCharacter(0)
, m_singleCharacterBuffer(0)
, m_havePassedStartNode(false)
, m_shouldHandleFirstLetter(false)
, m_stopsOnFormControls(behavior & TextIteratorStopsOnFormControls)
, m_shouldStop(false)
, m_emitsOriginalText(false)
{
ASSERT(behavior == TextIteratorDefaultBehavior || behavior == TextIteratorStopsOnFormControls);
if (!r)
return;
r->ownerDocument().updateLayoutIgnorePendingStylesheets();
Node* startNode = r->startContainer();
if (!startNode)
return;
Node* endNode = r->endContainer();
int startOffset = r->startOffset();
int endOffset = r->endOffset();
if (!startNode->offsetInCharacters()) {
if (startOffset >= 0 && startOffset < static_cast<int>(startNode->childNodeCount())) {
startNode = startNode->childNode(startOffset);
startOffset = 0;
}
}
if (!endNode->offsetInCharacters()) {
if (endOffset > 0 && endOffset <= static_cast<int>(endNode->childNodeCount())) {
endNode = endNode->childNode(endOffset - 1);
endOffset = lastOffsetInNode(endNode);
}
}
m_node = endNode;
setUpFullyClippedStack(m_fullyClippedStack, m_node);
m_offset = endOffset;
m_handledNode = false;
m_handledChildren = endOffset == 0;
m_startNode = startNode;
m_startOffset = startOffset;
m_endNode = endNode;
m_endOffset = endOffset;
#ifndef NDEBUG
// Need this just because of the assert.
m_positionNode = endNode;
#endif
m_lastTextNode = 0;
m_lastCharacter = '\n';
m_havePassedStartNode = false;
advance();
}
void SimplifiedBackwardsTextIterator::advance()
{
ASSERT(m_positionNode);
if (m_shouldStop)
return;
if (m_stopsOnFormControls && HTMLFormControlElement::enclosingFormControlElement(m_node)) {
m_shouldStop = true;
return;
}
m_positionNode = 0;
m_textLength = 0;
while (m_node && !m_havePassedStartNode) {
// Don't handle node if we start iterating at [node, 0].
if (!m_handledNode && !(m_node == m_endNode && m_endOffset == 0)) {
RenderObject* renderer = m_node->renderer();
if (renderer && renderer->isText() && m_node->nodeType() == Node::TEXT_NODE) {
// FIXME: What about CDATA_SECTION_NODE?
if (renderer->style().visibility() == VISIBLE && m_offset > 0)
m_handledNode = handleTextNode();
} else if (renderer && (renderer->isImage() || renderer->isWidget())) {
if (renderer->style().visibility() == VISIBLE && m_offset > 0)
m_handledNode = handleReplacedElement();
} else
m_handledNode = handleNonTextNode();
if (m_positionNode)
return;
}
if (!m_handledChildren && m_node->hasChildNodes()) {
m_node = m_node->lastChild();
pushFullyClippedState(m_fullyClippedStack, m_node);
} else {
// Exit empty containers as we pass over them or containers
// where [container, 0] is where we started iterating.
if (!m_handledNode
&& canHaveChildrenForEditing(m_node)
&& m_node->parentNode()
&& (!m_node->lastChild() || (m_node == m_endNode && !m_endOffset))) {
exitNode();
if (m_positionNode) {
m_handledNode = true;
m_handledChildren = true;
return;
}
}
// Exit all other containers.
while (!m_node->previousSibling()) {
if (!advanceRespectingRange(m_node->parentOrShadowHostNode()))
break;
m_fullyClippedStack.pop();
exitNode();
if (m_positionNode) {
m_handledNode = true;
m_handledChildren = true;
return;
}
}
m_fullyClippedStack.pop();
if (advanceRespectingRange(m_node->previousSibling()))
pushFullyClippedState(m_fullyClippedStack, m_node);
else
m_node = 0;
}
// For the purpose of word boundary detection,
// we should iterate all visible text and trailing (collapsed) whitespaces.
m_offset = m_node ? maxOffsetIncludingCollapsedSpaces(m_node) : 0;
m_handledNode = false;
m_handledChildren = false;
if (m_positionNode)
return;
}
}
bool SimplifiedBackwardsTextIterator::handleTextNode()
{
m_lastTextNode = m_node;
int startOffset;
int offsetInNode;
RenderText* renderer = handleFirstLetter(startOffset, offsetInNode);
if (!renderer)
return true;
String text = renderer->text();
if (!renderer->firstTextBox() && text.length() > 0)
return true;
m_positionEndOffset = m_offset;
m_offset = startOffset + offsetInNode;
m_positionNode = m_node;
m_positionStartOffset = m_offset;
ASSERT(0 <= m_positionStartOffset - offsetInNode && m_positionStartOffset - offsetInNode <= static_cast<int>(text.length()));
ASSERT(1 <= m_positionEndOffset - offsetInNode && m_positionEndOffset - offsetInNode <= static_cast<int>(text.length()));
ASSERT(m_positionStartOffset <= m_positionEndOffset);
m_textLength = m_positionEndOffset - m_positionStartOffset;
m_textCharacters = text.characters() + (m_positionStartOffset - offsetInNode);
ASSERT(m_textCharacters >= text.characters());
ASSERT(m_textCharacters + m_textLength <= text.characters() + static_cast<int>(text.length()));
m_lastCharacter = text[m_positionEndOffset - 1];
return !m_shouldHandleFirstLetter;
}
RenderText* SimplifiedBackwardsTextIterator::handleFirstLetter(int& startOffset, int& offsetInNode)
{
RenderText* renderer = toRenderText(m_node->renderer());
startOffset = (m_node == m_startNode) ? m_startOffset : 0;
if (!renderer->isTextFragment()) {
offsetInNode = 0;
return renderer;
}
RenderTextFragment* fragment = toRenderTextFragment(renderer);
int offsetAfterFirstLetter = fragment->start();
if (startOffset >= offsetAfterFirstLetter) {
ASSERT(!m_shouldHandleFirstLetter);
offsetInNode = offsetAfterFirstLetter;
return renderer;
}
if (!m_shouldHandleFirstLetter && offsetAfterFirstLetter < m_offset) {
m_shouldHandleFirstLetter = true;
offsetInNode = offsetAfterFirstLetter;
return renderer;
}
m_shouldHandleFirstLetter = false;
offsetInNode = 0;
return firstRenderTextInFirstLetter(fragment->firstLetter());
}
bool SimplifiedBackwardsTextIterator::handleReplacedElement()
{
unsigned index = m_node->nodeIndex();
// We want replaced elements to behave like punctuation for boundary
// finding, and to simply take up space for the selection preservation
// code in moveParagraphs, so we use a comma. Unconditionally emit
// here because this iterator is only used for boundary finding.
emitCharacter(',', m_node->parentNode(), index, index + 1);
return true;
}
bool SimplifiedBackwardsTextIterator::handleNonTextNode()
{
// We can use a linefeed in place of a tab because this simple iterator is only used to
// find boundaries, not actual content. A linefeed breaks words, sentences, and paragraphs.
if (shouldEmitNewlineForNode(m_node, m_emitsOriginalText) || shouldEmitNewlineAfterNode(m_node) || shouldEmitTabBeforeNode(m_node)) {
unsigned index = m_node->nodeIndex();
// The start of this emitted range is wrong. Ensuring correctness would require
// VisiblePositions and so would be slow. previousBoundary expects this.
emitCharacter('\n', m_node->parentNode(), index + 1, index + 1);
}
return true;
}
void SimplifiedBackwardsTextIterator::exitNode()
{
if (shouldEmitNewlineForNode(m_node, m_emitsOriginalText) || shouldEmitNewlineBeforeNode(m_node) || shouldEmitTabBeforeNode(m_node)) {
// The start of this emitted range is wrong. Ensuring correctness would require
// VisiblePositions and so would be slow. previousBoundary expects this.
emitCharacter('\n', m_node, 0, 0);
}
}
void SimplifiedBackwardsTextIterator::emitCharacter(UChar c, Node* node, int startOffset, int endOffset)
{
m_singleCharacterBuffer = c;
m_positionNode = node;
m_positionStartOffset = startOffset;
m_positionEndOffset = endOffset;
m_textCharacters = &m_singleCharacterBuffer;
m_textLength = 1;
m_lastCharacter = c;
}
bool SimplifiedBackwardsTextIterator::advanceRespectingRange(Node* next)
{
if (!next)
return false;
m_havePassedStartNode |= m_node == m_startNode;
if (m_havePassedStartNode)
return false;
m_node = next;
return true;
}
PassRefPtr<Range> SimplifiedBackwardsTextIterator::range() const
{
if (m_positionNode)
return Range::create(m_positionNode->document(), m_positionNode, m_positionStartOffset, m_positionNode, m_positionEndOffset);
return Range::create(m_startNode->document(), m_startNode, m_startOffset, m_startNode, m_startOffset);
}
// --------
CharacterIterator::CharacterIterator(const Range* r, TextIteratorBehavior behavior)
: m_offset(0)
, m_runOffset(0)
, m_atBreak(true)
, m_textIterator(r, behavior)
{
while (!atEnd() && m_textIterator.length() == 0)
m_textIterator.advance();
}
PassRefPtr<Range> CharacterIterator::range() const
{
RefPtr<Range> r = m_textIterator.range();
if (!m_textIterator.atEnd()) {
if (m_textIterator.length() <= 1) {
ASSERT(m_runOffset == 0);
} else {
Node* n = r->startContainer();
ASSERT(n == r->endContainer());
int offset = r->startOffset() + m_runOffset;
r->setStart(n, offset, ASSERT_NO_EXCEPTION);
r->setEnd(n, offset + 1, ASSERT_NO_EXCEPTION);
}
}
return r.release();
}
void CharacterIterator::advance(int count)
{
if (count <= 0) {
ASSERT(count == 0);
return;
}
m_atBreak = false;
// easy if there is enough left in the current m_textIterator run
int remaining = m_textIterator.length() - m_runOffset;
if (count < remaining) {
m_runOffset += count;
m_offset += count;
return;
}
// exhaust the current m_textIterator run
count -= remaining;
m_offset += remaining;
// move to a subsequent m_textIterator run
for (m_textIterator.advance(); !atEnd(); m_textIterator.advance()) {
int runLength = m_textIterator.length();
if (runLength == 0)
m_atBreak = true;
else {
// see whether this is m_textIterator to use
if (count < runLength) {
m_runOffset = count;
m_offset += count;
return;
}
// exhaust this m_textIterator run
count -= runLength;
m_offset += runLength;
}
}
// ran to the end of the m_textIterator... no more runs left
m_atBreak = true;
m_runOffset = 0;
}
String CharacterIterator::string(int numChars)
{
Vector<UChar> result;
result.reserveInitialCapacity(numChars);
while (numChars > 0 && !atEnd()) {
int runSize = std::min(numChars, length());
result.append(characters(), runSize);
numChars -= runSize;
advance(runSize);
}
return String::adopt(result);
}
static PassRefPtr<Range> characterSubrange(CharacterIterator& it, int offset, int length)
{
it.advance(offset);
RefPtr<Range> start = it.range();
if (length > 1)
it.advance(length - 1);
RefPtr<Range> end = it.range();
return Range::create(start->startContainer()->document(),
start->startContainer(), start->startOffset(),
end->endContainer(), end->endOffset());
}
BackwardsCharacterIterator::BackwardsCharacterIterator(const Range* range, TextIteratorBehavior behavior)
: m_offset(0)
, m_runOffset(0)
, m_atBreak(true)
, m_textIterator(range, behavior)
{
while (!atEnd() && !m_textIterator.length())
m_textIterator.advance();
}
PassRefPtr<Range> BackwardsCharacterIterator::range() const
{
RefPtr<Range> r = m_textIterator.range();
if (!m_textIterator.atEnd()) {
if (m_textIterator.length() <= 1)
ASSERT(m_runOffset == 0);
else {
Node* n = r->startContainer();
ASSERT(n == r->endContainer());
int offset = r->endOffset() - m_runOffset;
r->setStart(n, offset - 1, ASSERT_NO_EXCEPTION);
r->setEnd(n, offset, ASSERT_NO_EXCEPTION);
}
}
return r.release();
}
void BackwardsCharacterIterator::advance(int count)
{
if (count <= 0) {
ASSERT(!count);
return;
}
m_atBreak = false;
int remaining = m_textIterator.length() - m_runOffset;
if (count < remaining) {
m_runOffset += count;
m_offset += count;
return;
}
count -= remaining;
m_offset += remaining;
for (m_textIterator.advance(); !atEnd(); m_textIterator.advance()) {
int runLength = m_textIterator.length();
if (runLength == 0)
m_atBreak = true;
else {
if (count < runLength) {
m_runOffset = count;
m_offset += count;
return;
}
count -= runLength;
m_offset += runLength;
}
}
m_atBreak = true;
m_runOffset = 0;
}
// --------
WordAwareIterator::WordAwareIterator(const Range* r)
: m_previousText(0)
, m_didLookAhead(true) // so we consider the first chunk from the text iterator
, m_textIterator(r)
{
advance(); // get in position over the first chunk of text
}
WordAwareIterator::~WordAwareIterator()
{
}
// We're always in one of these modes:
// - The current chunk in the text iterator is our current chunk
// (typically its a piece of whitespace, or text that ended with whitespace)
// - The previous chunk in the text iterator is our current chunk
// (we looked ahead to the next chunk and found a word boundary)
// - We built up our own chunk of text from many chunks from the text iterator
// FIXME: Performance could be bad for huge spans next to each other that don't fall on word boundaries.
void WordAwareIterator::advance()
{
m_previousText = 0;
m_buffer.clear(); // toss any old buffer we built up
// If last time we did a look-ahead, start with that looked-ahead chunk now
if (!m_didLookAhead) {
ASSERT(!m_textIterator.atEnd());
m_textIterator.advance();
}
m_didLookAhead = false;
// Go to next non-empty chunk
while (!m_textIterator.atEnd() && m_textIterator.length() == 0)
m_textIterator.advance();
m_range = m_textIterator.range();
if (m_textIterator.atEnd())
return;
while (1) {
// If this chunk ends in whitespace we can just use it as our chunk.
if (isSpaceOrNewline(m_textIterator.characters()[m_textIterator.length() - 1]))
return;
// If this is the first chunk that failed, save it in previousText before look ahead
if (m_buffer.isEmpty()) {
m_previousText = m_textIterator.characters();
m_previousLength = m_textIterator.length();
}
// Look ahead to next chunk. If it is whitespace or a break, we can use the previous stuff
m_textIterator.advance();
if (m_textIterator.atEnd() || m_textIterator.length() == 0 || isSpaceOrNewline(m_textIterator.characters()[0])) {
m_didLookAhead = true;
return;
}
if (m_buffer.isEmpty()) {
// Start gobbling chunks until we get to a suitable stopping point
m_buffer.append(m_previousText, m_previousLength);
m_previousText = 0;
}
m_buffer.append(m_textIterator.characters(), m_textIterator.length());
int exception = 0;
m_range->setEnd(m_textIterator.range()->endContainer(), m_textIterator.range()->endOffset(), exception);
}
}
int WordAwareIterator::length() const
{
if (!m_buffer.isEmpty())
return m_buffer.size();
if (m_previousText)
return m_previousLength;
return m_textIterator.length();
}
const UChar* WordAwareIterator::characters() const
{
if (!m_buffer.isEmpty())
return m_buffer.data();
if (m_previousText)
return m_previousText;
return m_textIterator.characters();
}
// --------
static inline UChar foldQuoteMarkOrSoftHyphen(UChar c)
{
switch (c) {
case hebrewPunctuationGershayim:
case leftDoubleQuotationMark:
case rightDoubleQuotationMark:
return '"';
case hebrewPunctuationGeresh:
case leftSingleQuotationMark:
case rightSingleQuotationMark:
return '\'';
case softHyphen:
// Replace soft hyphen with an ignorable character so that their presence or absence will
// not affect string comparison.
return 0;
default:
return c;
}
}
static inline void foldQuoteMarksAndSoftHyphens(String& s)
{
s.replace(hebrewPunctuationGeresh, '\'');
s.replace(hebrewPunctuationGershayim, '"');
s.replace(leftDoubleQuotationMark, '"');
s.replace(leftSingleQuotationMark, '\'');
s.replace(rightDoubleQuotationMark, '"');
s.replace(rightSingleQuotationMark, '\'');
// Replace soft hyphen with an ignorable character so that their presence or absence will
// not affect string comparison.
s.replace(softHyphen, 0);
}
#if USE(ICU_UNICODE) && !UCONFIG_NO_COLLATION
static inline void foldQuoteMarksAndSoftHyphens(UChar* data, size_t length)
{
for (size_t i = 0; i < length; ++i)
data[i] = foldQuoteMarkOrSoftHyphen(data[i]);
}
static const size_t minimumSearchBufferSize = 8192;
#ifndef NDEBUG
static bool searcherInUse;
#endif
static UStringSearch* createSearcher()
{
// Provide a non-empty pattern and non-empty text so usearch_open will not fail,
// but it doesn't matter exactly what it is, since we don't perform any searches
// without setting both the pattern and the text.
UErrorCode status = U_ZERO_ERROR;
String searchCollatorName = makeString(currentSearchLocaleID(), "@collation=search");
UStringSearch* searcher = usearch_open(&newlineCharacter, 1, &newlineCharacter, 1, searchCollatorName.utf8().data(), 0, &status);
ASSERT(status == U_ZERO_ERROR || status == U_USING_FALLBACK_WARNING || status == U_USING_DEFAULT_WARNING);
return searcher;
}
static UStringSearch* searcher()
{
static UStringSearch* searcher = createSearcher();
return searcher;
}
static inline void lockSearcher()
{
#ifndef NDEBUG
ASSERT(!searcherInUse);
searcherInUse = true;
#endif
}
static inline void unlockSearcher()
{
#ifndef NDEBUG
ASSERT(searcherInUse);
searcherInUse = false;
#endif
}
// ICU's search ignores the distinction between small kana letters and ones
// that are not small, and also characters that differ only in the voicing
// marks when considering only primary collation strength differences.
// This is not helpful for end users, since these differences make words
// distinct, so for our purposes we need these to be considered.
// The Unicode folks do not think the collation algorithm should be
// changed. To work around this, we would like to tailor the ICU searcher,
// but we can't get that to work yet. So instead, we check for cases where
// these differences occur, and skip those matches.
// We refer to the above technique as the "kana workaround". The next few
// functions are helper functinos for the kana workaround.
static inline bool isKanaLetter(UChar character)
{
// Hiragana letters.
if (character >= 0x3041 && character <= 0x3096)
return true;
// Katakana letters.
if (character >= 0x30A1 && character <= 0x30FA)
return true;
if (character >= 0x31F0 && character <= 0x31FF)
return true;
// Halfwidth katakana letters.
if (character >= 0xFF66 && character <= 0xFF9D && character != 0xFF70)
return true;
return false;
}
static inline bool isSmallKanaLetter(UChar character)
{
ASSERT(isKanaLetter(character));
switch (character) {
case 0x3041: // HIRAGANA LETTER SMALL A
case 0x3043: // HIRAGANA LETTER SMALL I
case 0x3045: // HIRAGANA LETTER SMALL U
case 0x3047: // HIRAGANA LETTER SMALL E
case 0x3049: // HIRAGANA LETTER SMALL O
case 0x3063: // HIRAGANA LETTER SMALL TU
case 0x3083: // HIRAGANA LETTER SMALL YA
case 0x3085: // HIRAGANA LETTER SMALL YU
case 0x3087: // HIRAGANA LETTER SMALL YO
case 0x308E: // HIRAGANA LETTER SMALL WA
case 0x3095: // HIRAGANA LETTER SMALL KA
case 0x3096: // HIRAGANA LETTER SMALL KE
case 0x30A1: // KATAKANA LETTER SMALL A
case 0x30A3: // KATAKANA LETTER SMALL I
case 0x30A5: // KATAKANA LETTER SMALL U
case 0x30A7: // KATAKANA LETTER SMALL E
case 0x30A9: // KATAKANA LETTER SMALL O
case 0x30C3: // KATAKANA LETTER SMALL TU
case 0x30E3: // KATAKANA LETTER SMALL YA
case 0x30E5: // KATAKANA LETTER SMALL YU
case 0x30E7: // KATAKANA LETTER SMALL YO
case 0x30EE: // KATAKANA LETTER SMALL WA
case 0x30F5: // KATAKANA LETTER SMALL KA
case 0x30F6: // KATAKANA LETTER SMALL KE
case 0x31F0: // KATAKANA LETTER SMALL KU
case 0x31F1: // KATAKANA LETTER SMALL SI
case 0x31F2: // KATAKANA LETTER SMALL SU
case 0x31F3: // KATAKANA LETTER SMALL TO
case 0x31F4: // KATAKANA LETTER SMALL NU
case 0x31F5: // KATAKANA LETTER SMALL HA
case 0x31F6: // KATAKANA LETTER SMALL HI
case 0x31F7: // KATAKANA LETTER SMALL HU
case 0x31F8: // KATAKANA LETTER SMALL HE
case 0x31F9: // KATAKANA LETTER SMALL HO
case 0x31FA: // KATAKANA LETTER SMALL MU
case 0x31FB: // KATAKANA LETTER SMALL RA
case 0x31FC: // KATAKANA LETTER SMALL RI
case 0x31FD: // KATAKANA LETTER SMALL RU
case 0x31FE: // KATAKANA LETTER SMALL RE
case 0x31FF: // KATAKANA LETTER SMALL RO
case 0xFF67: // HALFWIDTH KATAKANA LETTER SMALL A
case 0xFF68: // HALFWIDTH KATAKANA LETTER SMALL I
case 0xFF69: // HALFWIDTH KATAKANA LETTER SMALL U
case 0xFF6A: // HALFWIDTH KATAKANA LETTER SMALL E
case 0xFF6B: // HALFWIDTH KATAKANA LETTER SMALL O
case 0xFF6C: // HALFWIDTH KATAKANA LETTER SMALL YA
case 0xFF6D: // HALFWIDTH KATAKANA LETTER SMALL YU
case 0xFF6E: // HALFWIDTH KATAKANA LETTER SMALL YO
case 0xFF6F: // HALFWIDTH KATAKANA LETTER SMALL TU
return true;
}
return false;
}
enum VoicedSoundMarkType { NoVoicedSoundMark, VoicedSoundMark, SemiVoicedSoundMark };
static inline VoicedSoundMarkType composedVoicedSoundMark(UChar character)
{
ASSERT(isKanaLetter(character));
switch (character) {
case 0x304C: // HIRAGANA LETTER GA
case 0x304E: // HIRAGANA LETTER GI
case 0x3050: // HIRAGANA LETTER GU
case 0x3052: // HIRAGANA LETTER GE
case 0x3054: // HIRAGANA LETTER GO
case 0x3056: // HIRAGANA LETTER ZA
case 0x3058: // HIRAGANA LETTER ZI
case 0x305A: // HIRAGANA LETTER ZU
case 0x305C: // HIRAGANA LETTER ZE
case 0x305E: // HIRAGANA LETTER ZO
case 0x3060: // HIRAGANA LETTER DA
case 0x3062: // HIRAGANA LETTER DI
case 0x3065: // HIRAGANA LETTER DU
case 0x3067: // HIRAGANA LETTER DE
case 0x3069: // HIRAGANA LETTER DO
case 0x3070: // HIRAGANA LETTER BA
case 0x3073: // HIRAGANA LETTER BI
case 0x3076: // HIRAGANA LETTER BU
case 0x3079: // HIRAGANA LETTER BE
case 0x307C: // HIRAGANA LETTER BO
case 0x3094: // HIRAGANA LETTER VU
case 0x30AC: // KATAKANA LETTER GA
case 0x30AE: // KATAKANA LETTER GI
case 0x30B0: // KATAKANA LETTER GU
case 0x30B2: // KATAKANA LETTER GE
case 0x30B4: // KATAKANA LETTER GO
case 0x30B6: // KATAKANA LETTER ZA
case 0x30B8: // KATAKANA LETTER ZI
case 0x30BA: // KATAKANA LETTER ZU
case 0x30BC: // KATAKANA LETTER ZE
case 0x30BE: // KATAKANA LETTER ZO
case 0x30C0: // KATAKANA LETTER DA
case 0x30C2: // KATAKANA LETTER DI
case 0x30C5: // KATAKANA LETTER DU
case 0x30C7: // KATAKANA LETTER DE
case 0x30C9: // KATAKANA LETTER DO
case 0x30D0: // KATAKANA LETTER BA
case 0x30D3: // KATAKANA LETTER BI
case 0x30D6: // KATAKANA LETTER BU
case 0x30D9: // KATAKANA LETTER BE
case 0x30DC: // KATAKANA LETTER BO
case 0x30F4: // KATAKANA LETTER VU
case 0x30F7: // KATAKANA LETTER VA
case 0x30F8: // KATAKANA LETTER VI
case 0x30F9: // KATAKANA LETTER VE
case 0x30FA: // KATAKANA LETTER VO
return VoicedSoundMark;
case 0x3071: // HIRAGANA LETTER PA
case 0x3074: // HIRAGANA LETTER PI
case 0x3077: // HIRAGANA LETTER PU
case 0x307A: // HIRAGANA LETTER PE
case 0x307D: // HIRAGANA LETTER PO
case 0x30D1: // KATAKANA LETTER PA
case 0x30D4: // KATAKANA LETTER PI
case 0x30D7: // KATAKANA LETTER PU
case 0x30DA: // KATAKANA LETTER PE
case 0x30DD: // KATAKANA LETTER PO
return SemiVoicedSoundMark;
}
return NoVoicedSoundMark;
}
static inline bool isCombiningVoicedSoundMark(UChar character)
{
switch (character) {
case 0x3099: // COMBINING KATAKANA-HIRAGANA VOICED SOUND MARK
case 0x309A: // COMBINING KATAKANA-HIRAGANA SEMI-VOICED SOUND MARK
return true;
}
return false;
}
static inline bool containsKanaLetters(const String& pattern)
{
const UChar* characters = pattern.characters();
unsigned length = pattern.length();
for (unsigned i = 0; i < length; ++i) {
if (isKanaLetter(characters[i]))
return true;
}
return false;
}
static void normalizeCharacters(const UChar* characters, unsigned length, Vector<UChar>& buffer)
{
ASSERT(length);
buffer.resize(length);
UErrorCode status = U_ZERO_ERROR;
size_t bufferSize = unorm_normalize(characters, length, UNORM_NFC, 0, buffer.data(), length, &status);
ASSERT(status == U_ZERO_ERROR || status == U_STRING_NOT_TERMINATED_WARNING || status == U_BUFFER_OVERFLOW_ERROR);
ASSERT(bufferSize);
buffer.resize(bufferSize);
if (status == U_ZERO_ERROR || status == U_STRING_NOT_TERMINATED_WARNING)
return;
status = U_ZERO_ERROR;
unorm_normalize(characters, length, UNORM_NFC, 0, buffer.data(), bufferSize, &status);
ASSERT(status == U_STRING_NOT_TERMINATED_WARNING);
}
static bool isNonLatin1Separator(UChar32 character)
{
ASSERT_ARG(character, character >= 256);
return U_GET_GC_MASK(character) & (U_GC_S_MASK | U_GC_P_MASK | U_GC_Z_MASK | U_GC_CF_MASK);
}
static inline bool isSeparator(UChar32 character)
{
static const bool latin1SeparatorTable[256] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, // space ! " # $ % & ' ( ) * + , - . /
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, // : ; < = > ?
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // @
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, // [ \ ] ^ _
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, // `
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, // { | } ~
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,
1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0
};
if (character < 256)
return latin1SeparatorTable[character];
return isNonLatin1Separator(character);
}
inline SearchBuffer::SearchBuffer(const String& target, FindOptions options)
: m_target(target)
, m_options(options)
, m_prefixLength(0)
, m_atBreak(true)
, m_needsMoreContext(options & AtWordStarts)
, m_targetRequiresKanaWorkaround(containsKanaLetters(m_target))
{
ASSERT(!m_target.isEmpty());
// FIXME: We'd like to tailor the searcher to fold quote marks for us instead
// of doing it in a separate replacement pass here, but ICU doesn't offer a way
// to add tailoring on top of the locale-specific tailoring as of this writing.
foldQuoteMarksAndSoftHyphens(m_target);
size_t targetLength = m_target.length();
m_buffer.reserveInitialCapacity(std::max(targetLength * 8, minimumSearchBufferSize));
m_overlap = m_buffer.capacity() / 4;
if ((m_options & AtWordStarts) && targetLength) {
UChar32 targetFirstCharacter;
U16_GET(m_target.characters(), 0, 0, targetLength, targetFirstCharacter);
// Characters in the separator category never really occur at the beginning of a word,
// so if the target begins with such a character, we just ignore the AtWordStart option.
if (isSeparator(targetFirstCharacter)) {
m_options &= ~AtWordStarts;
m_needsMoreContext = false;
}
}
// Grab the single global searcher.
// If we ever have a reason to do more than once search buffer at once, we'll have
// to move to multiple searchers.
lockSearcher();
UStringSearch* searcher = WebCore::searcher();
UCollator* collator = usearch_getCollator(searcher);
UCollationStrength strength;
USearchAttributeValue comparator;
if (m_options & CaseInsensitive) {
// Without loss of generality, have 'e' match {'e', 'E', 'é', 'É'} and 'é' match {'é', 'É'}.
strength = UCOL_SECONDARY;
comparator = USEARCH_PATTERN_BASE_WEIGHT_IS_WILDCARD;
} else {
// Without loss of generality, have 'e' match {'e'} and 'é' match {'é'}.
strength = UCOL_TERTIARY;
comparator = USEARCH_STANDARD_ELEMENT_COMPARISON;
}
if (ucol_getStrength(collator) != strength) {
ucol_setStrength(collator, strength);
usearch_reset(searcher);
}
UErrorCode status = U_ZERO_ERROR;
usearch_setAttribute(searcher, USEARCH_ELEMENT_COMPARISON, comparator, &status);
ASSERT(status == U_ZERO_ERROR);
usearch_setPattern(searcher, m_target.characters(), targetLength, &status);
ASSERT(status == U_ZERO_ERROR);
// The kana workaround requires a normalized copy of the target string.
if (m_targetRequiresKanaWorkaround)
normalizeCharacters(m_target.characters(), m_target.length(), m_normalizedTarget);
}
inline SearchBuffer::~SearchBuffer()
{
// Leave the static object pointing to a valid string.
UErrorCode status = U_ZERO_ERROR;
usearch_setPattern(WebCore::searcher(), &newlineCharacter, 1, &status);
ASSERT(status == U_ZERO_ERROR);
unlockSearcher();
}
inline size_t SearchBuffer::append(const UChar* characters, size_t length)
{
ASSERT(length);
if (m_atBreak) {
m_buffer.shrink(0);
m_prefixLength = 0;
m_atBreak = false;
} else if (m_buffer.size() == m_buffer.capacity()) {
memcpy(m_buffer.data(), m_buffer.data() + m_buffer.size() - m_overlap, m_overlap * sizeof(UChar));
m_prefixLength -= std::min(m_prefixLength, m_buffer.size() - m_overlap);
m_buffer.shrink(m_overlap);
}
size_t oldLength = m_buffer.size();
size_t usableLength = std::min(m_buffer.capacity() - oldLength, length);
ASSERT(usableLength);
m_buffer.append(characters, usableLength);
foldQuoteMarksAndSoftHyphens(m_buffer.data() + oldLength, usableLength);
return usableLength;
}
inline bool SearchBuffer::needsMoreContext() const
{
return m_needsMoreContext;
}
inline void SearchBuffer::prependContext(const UChar* characters, size_t length)
{
ASSERT(m_needsMoreContext);
ASSERT(m_prefixLength == m_buffer.size());
if (!length)
return;
m_atBreak = false;
size_t wordBoundaryContextStart = length;
if (wordBoundaryContextStart) {
U16_BACK_1(characters, 0, wordBoundaryContextStart);
wordBoundaryContextStart = startOfLastWordBoundaryContext(characters, wordBoundaryContextStart);
}
size_t usableLength = std::min(m_buffer.capacity() - m_prefixLength, length - wordBoundaryContextStart);
m_buffer.insert(0, characters + length - usableLength, usableLength);
m_prefixLength += usableLength;
if (wordBoundaryContextStart || m_prefixLength == m_buffer.capacity())
m_needsMoreContext = false;
}
inline bool SearchBuffer::atBreak() const
{
return m_atBreak;
}
inline void SearchBuffer::reachedBreak()
{
m_atBreak = true;
}
inline bool SearchBuffer::isBadMatch(const UChar* match, size_t matchLength) const
{
// This function implements the kana workaround. If usearch treats
// it as a match, but we do not want to, then it's a "bad match".
if (!m_targetRequiresKanaWorkaround)
return false;
// Normalize into a match buffer. We reuse a single buffer rather than
// creating a new one each time.
normalizeCharacters(match, matchLength, m_normalizedMatch);
const UChar* a = m_normalizedTarget.begin();
const UChar* aEnd = m_normalizedTarget.end();
const UChar* b = m_normalizedMatch.begin();
const UChar* bEnd = m_normalizedMatch.end();
while (true) {
// Skip runs of non-kana-letter characters. This is necessary so we can
// correctly handle strings where the target and match have different-length
// runs of characters that match, while still double checking the correctness
// of matches of kana letters with other kana letters.
while (a != aEnd && !isKanaLetter(*a))
++a;
while (b != bEnd && !isKanaLetter(*b))
++b;
// If we reached the end of either the target or the match, we should have
// reached the end of both; both should have the same number of kana letters.
if (a == aEnd || b == bEnd) {
ASSERT(a == aEnd);
ASSERT(b == bEnd);
return false;
}
// Check for differences in the kana letter character itself.
if (isSmallKanaLetter(*a) != isSmallKanaLetter(*b))
return true;
if (composedVoicedSoundMark(*a) != composedVoicedSoundMark(*b))
return true;
++a;
++b;
// Check for differences in combining voiced sound marks found after the letter.
while (1) {
if (!(a != aEnd && isCombiningVoicedSoundMark(*a))) {
if (b != bEnd && isCombiningVoicedSoundMark(*b))
return true;
break;
}
if (!(b != bEnd && isCombiningVoicedSoundMark(*b)))
return true;
if (*a != *b)
return true;
++a;
++b;
}
}
}
inline bool SearchBuffer::isWordStartMatch(size_t start, size_t length) const
{
ASSERT(m_options & AtWordStarts);
if (!start)
return true;
int size = m_buffer.size();
int offset = start;
UChar32 firstCharacter;
U16_GET(m_buffer.data(), 0, offset, size, firstCharacter);
if (m_options & TreatMedialCapitalAsWordStart) {
UChar32 previousCharacter;
U16_PREV(m_buffer.data(), 0, offset, previousCharacter);
if (isSeparator(firstCharacter)) {
// The start of a separator run is a word start (".org" in "webkit.org").
if (!isSeparator(previousCharacter))
return true;
} else if (isASCIIUpper(firstCharacter)) {
// The start of an uppercase run is a word start ("Kit" in "WebKit").
if (!isASCIIUpper(previousCharacter))
return true;
// The last character of an uppercase run followed by a non-separator, non-digit
// is a word start ("Request" in "XMLHTTPRequest").
offset = start;
U16_FWD_1(m_buffer.data(), offset, size);
UChar32 nextCharacter = 0;
if (offset < size)
U16_GET(m_buffer.data(), 0, offset, size, nextCharacter);
if (!isASCIIUpper(nextCharacter) && !isASCIIDigit(nextCharacter) && !isSeparator(nextCharacter))
return true;
} else if (isASCIIDigit(firstCharacter)) {
// The start of a digit run is a word start ("2" in "WebKit2").
if (!isASCIIDigit(previousCharacter))
return true;
} else if (isSeparator(previousCharacter) || isASCIIDigit(previousCharacter)) {
// The start of a non-separator, non-uppercase, non-digit run is a word start,
// except after an uppercase. ("org" in "webkit.org", but not "ore" in "WebCore").
return true;
}
}
// Chinese and Japanese lack word boundary marks, and there is no clear agreement on what constitutes
// a word, so treat the position before any CJK character as a word start.
if (Font::isCJKIdeographOrSymbol(firstCharacter))
return true;
size_t wordBreakSearchStart = start + length;
while (wordBreakSearchStart > start)
wordBreakSearchStart = findNextWordFromIndex(m_buffer.data(), m_buffer.size(), wordBreakSearchStart, false /* backwards */);
return wordBreakSearchStart == start;
}
inline size_t SearchBuffer::search(size_t& start)
{
size_t size = m_buffer.size();
if (m_atBreak) {
if (!size)
return 0;
} else {
if (size != m_buffer.capacity())
return 0;
}
UStringSearch* searcher = WebCore::searcher();
UErrorCode status = U_ZERO_ERROR;
usearch_setText(searcher, m_buffer.data(), size, &status);
ASSERT(status == U_ZERO_ERROR);
usearch_setOffset(searcher, m_prefixLength, &status);
ASSERT(status == U_ZERO_ERROR);
int matchStart = usearch_next(searcher, &status);
ASSERT(status == U_ZERO_ERROR);
nextMatch:
if (!(matchStart >= 0 && static_cast<size_t>(matchStart) < size)) {
ASSERT(matchStart == USEARCH_DONE);
return 0;
}
// Matches that start in the overlap area are only tentative.
// The same match may appear later, matching more characters,
// possibly including a combining character that's not yet in the buffer.
if (!m_atBreak && static_cast<size_t>(matchStart) >= size - m_overlap) {
size_t overlap = m_overlap;
if (m_options & AtWordStarts) {
// Ensure that there is sufficient context before matchStart the next time around for
// determining if it is at a word boundary.
int wordBoundaryContextStart = matchStart;
U16_BACK_1(m_buffer.data(), 0, wordBoundaryContextStart);
wordBoundaryContextStart = startOfLastWordBoundaryContext(m_buffer.data(), wordBoundaryContextStart);
overlap = std::min(size - 1, std::max(overlap, size - wordBoundaryContextStart));
}
memcpy(m_buffer.data(), m_buffer.data() + size - overlap, overlap * sizeof(UChar));
m_prefixLength -= std::min(m_prefixLength, size - overlap);
m_buffer.shrink(overlap);
return 0;
}
size_t matchedLength = usearch_getMatchedLength(searcher);
ASSERT_WITH_SECURITY_IMPLICATION(matchStart + matchedLength <= size);
// If this match is "bad", move on to the next match.
if (isBadMatch(m_buffer.data() + matchStart, matchedLength) || ((m_options & AtWordStarts) && !isWordStartMatch(matchStart, matchedLength))) {
matchStart = usearch_next(searcher, &status);
ASSERT(status == U_ZERO_ERROR);
goto nextMatch;
}
size_t newSize = size - (matchStart + 1);
memmove(m_buffer.data(), m_buffer.data() + matchStart + 1, newSize * sizeof(UChar));
m_prefixLength -= std::min<size_t>(m_prefixLength, matchStart + 1);
m_buffer.shrink(newSize);
start = size - matchStart;
return matchedLength;
}
#else // !ICU_UNICODE
inline SearchBuffer::SearchBuffer(const String& target, FindOptions options)
: m_target(options & CaseInsensitive ? target.foldCase() : target)
, m_options(options)
, m_buffer(m_target.length())
, m_isCharacterStartBuffer(m_target.length())
, m_isBufferFull(false)
, m_cursor(0)
{
ASSERT(!m_target.isEmpty());
m_target.replace(noBreakSpace, ' ');
foldQuoteMarksAndSoftHyphens(m_target);
}
inline SearchBuffer::~SearchBuffer()
{
}
inline void SearchBuffer::reachedBreak()
{
m_cursor = 0;
m_isBufferFull = false;
}
inline bool SearchBuffer::atBreak() const
{
return !m_cursor && !m_isBufferFull;
}
inline void SearchBuffer::append(UChar c, bool isStart)
{
m_buffer[m_cursor] = c == noBreakSpace ? ' ' : foldQuoteMarkOrSoftHyphen(c);
m_isCharacterStartBuffer[m_cursor] = isStart;
if (++m_cursor == m_target.length()) {
m_cursor = 0;
m_isBufferFull = true;
}
}
inline size_t SearchBuffer::append(const UChar* characters, size_t length)
{
ASSERT(length);
if (!(m_options & CaseInsensitive)) {
append(characters[0], true);
return 1;
}
const int maxFoldedCharacters = 16; // sensible maximum is 3, this should be more than enough
UChar foldedCharacters[maxFoldedCharacters];
UErrorCode status = U_ZERO_ERROR;
int numFoldedCharacters = u_strFoldCase(foldedCharacters, maxFoldedCharacters, characters, 1, U_FOLD_CASE_DEFAULT, &status);
ASSERT(U_SUCCESS(status));
ASSERT(numFoldedCharacters);
ASSERT(numFoldedCharacters <= maxFoldedCharacters);
if (!error && numFoldedCharacters) {
numFoldedCharacters = min(numFoldedCharacters, maxFoldedCharacters);
append(foldedCharacters[0], true);
for (int i = 1; i < numFoldedCharacters; ++i)
append(foldedCharacters[i], false);
}
return 1;
}
inline bool SearchBuffer::needsMoreContext() const
{
return false;
}
void SearchBuffer::prependContext(const UChar*, size_t)
{
ASSERT_NOT_REACHED();
}
inline size_t SearchBuffer::search(size_t& start)
{
if (!m_isBufferFull)
return 0;
if (!m_isCharacterStartBuffer[m_cursor])
return 0;
size_t tailSpace = m_target.length() - m_cursor;
if (memcmp(&m_buffer[m_cursor], m_target.characters(), tailSpace * sizeof(UChar)) != 0)
return 0;
if (memcmp(&m_buffer[0], m_target.characters() + tailSpace, m_cursor * sizeof(UChar)) != 0)
return 0;
start = length();
// Now that we've found a match once, we don't want to find it again, because those
// are the SearchBuffer semantics, allowing for a buffer where you append more than one
// character at a time. To do this we take advantage of m_isCharacterStartBuffer, but if
// we want to get rid of that in the future we could track this with a separate boolean
// or even move the characters to the start of the buffer and set m_isBufferFull to false.
m_isCharacterStartBuffer[m_cursor] = false;
return start;
}
// Returns the number of characters that were appended to the buffer (what we are searching in).
// That's not necessarily the same length as the passed-in target string, because case folding
// can make two strings match even though they're not the same length.
size_t SearchBuffer::length() const
{
size_t bufferSize = m_target.length();
size_t length = 0;
for (size_t i = 0; i < bufferSize; ++i)
length += m_isCharacterStartBuffer[i];
return length;
}
#endif // !ICU_UNICODE
// --------
int TextIterator::rangeLength(const Range* r, bool forSelectionPreservation)
{
int length = 0;
for (TextIterator it(r, forSelectionPreservation ? TextIteratorEmitsCharactersBetweenAllVisiblePositions : TextIteratorDefaultBehavior); !it.atEnd(); it.advance())
length += it.length();
return length;
}
PassRefPtr<Range> TextIterator::subrange(Range* entireRange, int characterOffset, int characterCount)
{
CharacterIterator entireRangeIterator(entireRange);
return characterSubrange(entireRangeIterator, characterOffset, characterCount);
}
PassRefPtr<Range> TextIterator::rangeFromLocationAndLength(ContainerNode* scope, int rangeLocation, int rangeLength, bool forSelectionPreservation)
{
RefPtr<Range> resultRange = scope->document().createRange();
int docTextPosition = 0;
int rangeEnd = rangeLocation + rangeLength;
bool startRangeFound = false;
RefPtr<Range> textRunRange;
TextIterator it(rangeOfContents(*scope).get(), forSelectionPreservation ? TextIteratorEmitsCharactersBetweenAllVisiblePositions : TextIteratorDefaultBehavior);
// FIXME: the atEnd() check shouldn't be necessary, workaround for <http://bugs.webkit.org/show_bug.cgi?id=6289>.
if (rangeLocation == 0 && rangeLength == 0 && it.atEnd()) {
textRunRange = it.range();
resultRange->setStart(textRunRange->startContainer(), 0, ASSERT_NO_EXCEPTION);
resultRange->setEnd(textRunRange->startContainer(), 0, ASSERT_NO_EXCEPTION);
return resultRange.release();
}
for (; !it.atEnd(); it.advance()) {
int len = it.length();
textRunRange = it.range();
bool foundStart = rangeLocation >= docTextPosition && rangeLocation <= docTextPosition + len;
bool foundEnd = rangeEnd >= docTextPosition && rangeEnd <= docTextPosition + len;
// Fix textRunRange->endPosition(), but only if foundStart || foundEnd, because it is only
// in those cases that textRunRange is used.
if (foundEnd) {
// FIXME: This is a workaround for the fact that the end of a run is often at the wrong
// position for emitted '\n's.
if (len == 1 && it.characterAt(0) == '\n') {
it.advance();
if (!it.atEnd()) {
RefPtr<Range> range = it.range();
textRunRange->setEnd(range->startContainer(), range->startOffset(), ASSERT_NO_EXCEPTION);
} else {
Position runStart = textRunRange->startPosition();
Position runEnd = VisiblePosition(runStart).next().deepEquivalent();
if (runEnd.isNotNull())
textRunRange->setEnd(runEnd.containerNode(), runEnd.computeOffsetInContainerNode(), ASSERT_NO_EXCEPTION);
}
}
}
if (foundStart) {
startRangeFound = true;
int exception = 0;
if (textRunRange->startContainer()->isTextNode()) {
int offset = rangeLocation - docTextPosition;
resultRange->setStart(textRunRange->startContainer(), offset + textRunRange->startOffset(), exception);
} else {
if (rangeLocation == docTextPosition)
resultRange->setStart(textRunRange->startContainer(), textRunRange->startOffset(), exception);
else
resultRange->setStart(textRunRange->endContainer(), textRunRange->endOffset(), exception);
}
}
if (foundEnd) {
int exception = 0;
if (textRunRange->startContainer()->isTextNode()) {
int offset = rangeEnd - docTextPosition;
resultRange->setEnd(textRunRange->startContainer(), offset + textRunRange->startOffset(), exception);
} else {
if (rangeEnd == docTextPosition)
resultRange->setEnd(textRunRange->startContainer(), textRunRange->startOffset(), exception);
else
resultRange->setEnd(textRunRange->endContainer(), textRunRange->endOffset(), exception);
}
docTextPosition += len;
break;
}
docTextPosition += len;
}
if (!startRangeFound)
return 0;
if (rangeLength != 0 && rangeEnd > docTextPosition) { // rangeEnd is out of bounds
int exception = 0;
resultRange->setEnd(textRunRange->endContainer(), textRunRange->endOffset(), exception);
}
return resultRange.release();
}
bool TextIterator::getLocationAndLengthFromRange(Node* scope, const Range* range, size_t& location, size_t& length)
{
location = notFound;
length = 0;
if (!range->startContainer())
return false;
// The critical assumption is that this only gets called with ranges that
// concentrate on a given area containing the selection root. This is done
// because of text fields and textareas. The DOM for those is not
// directly in the document DOM, so ensure that the range does not cross a
// boundary of one of those.
if (range->startContainer() != scope && !range->startContainer()->isDescendantOf(scope))
return false;
if (range->endContainer() != scope && !range->endContainer()->isDescendantOf(scope))
return false;
RefPtr<Range> testRange = Range::create(scope->document(), scope, 0, range->startContainer(), range->startOffset());
ASSERT(testRange->startContainer() == scope);
location = TextIterator::rangeLength(testRange.get());
testRange->setEnd(range->endContainer(), range->endOffset(), IGNORE_EXCEPTION);
ASSERT(testRange->startContainer() == scope);
length = TextIterator::rangeLength(testRange.get()) - location;
return true;
}
// --------
String plainText(const Range* r, TextIteratorBehavior defaultBehavior, bool isDisplayString)
{
// The initial buffer size can be critical for performance: https://bugs.webkit.org/show_bug.cgi?id=81192
static const unsigned initialCapacity = 1 << 15;
unsigned bufferLength = 0;
StringBuilder builder;
builder.reserveCapacity(initialCapacity);
TextIteratorBehavior behavior = defaultBehavior;
if (!isDisplayString)
behavior = static_cast<TextIteratorBehavior>(behavior | TextIteratorEmitsTextsWithoutTranscoding);
for (TextIterator it(r, behavior); !it.atEnd(); it.advance()) {
it.appendTextToStringBuilder(builder);
bufferLength += it.length();
}
if (!bufferLength)
return emptyString();
String result = builder.toString();
if (isDisplayString)
r->ownerDocument().displayStringModifiedByEncoding(result);
return result;
}
static PassRefPtr<Range> collapsedToBoundary(const Range* range, bool forward)
{
RefPtr<Range> result = range->cloneRange(ASSERT_NO_EXCEPTION);
result->collapse(!forward, ASSERT_NO_EXCEPTION);
return result.release();
}
static size_t findPlainText(CharacterIterator& it, const String& target, FindOptions options, size_t& matchStart)
{
matchStart = 0;
size_t matchLength = 0;
SearchBuffer buffer(target, options);
if (buffer.needsMoreContext()) {
RefPtr<Range> startRange = it.range();
RefPtr<Range> beforeStartRange = startRange->ownerDocument().createRange();
beforeStartRange->setEnd(startRange->startContainer(), startRange->startOffset(), IGNORE_EXCEPTION);
for (SimplifiedBackwardsTextIterator backwardsIterator(beforeStartRange.get()); !backwardsIterator.atEnd(); backwardsIterator.advance()) {
buffer.prependContext(backwardsIterator.characters(), backwardsIterator.length());
if (!buffer.needsMoreContext())
break;
}
}
while (!it.atEnd()) {
it.advance(buffer.append(it.characters(), it.length()));
tryAgain:
size_t matchStartOffset;
if (size_t newMatchLength = buffer.search(matchStartOffset)) {
// Note that we found a match, and where we found it.
size_t lastCharacterInBufferOffset = it.characterOffset();
ASSERT(lastCharacterInBufferOffset >= matchStartOffset);
matchStart = lastCharacterInBufferOffset - matchStartOffset;
matchLength = newMatchLength;
// If searching forward, stop on the first match.
// If searching backward, don't stop, so we end up with the last match.
if (!(options & Backwards))
break;
goto tryAgain;
}
if (it.atBreak() && !buffer.atBreak()) {
buffer.reachedBreak();
goto tryAgain;
}
}
return matchLength;
}
PassRefPtr<Range> findPlainText(const Range* range, const String& target, FindOptions options)
{
// First, find the text.
size_t matchStart;
size_t matchLength;
{
CharacterIterator findIterator(range, TextIteratorEntersTextControls);
matchLength = findPlainText(findIterator, target, options, matchStart);
if (!matchLength)
return collapsedToBoundary(range, !(options & Backwards));
}
// Then, find the document position of the start and the end of the text.
CharacterIterator computeRangeIterator(range, TextIteratorEntersTextControls);
return characterSubrange(computeRangeIterator, matchStart, matchLength);
}
}