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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: sw=2 ts=8 et :
*/
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_ContentCache_h
#define mozilla_ContentCache_h
#include <stdint.h>
#include "mozilla/widget/IMEData.h"
#include "mozilla/Assertions.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/EventForwards.h"
#include "mozilla/Maybe.h"
#include "mozilla/ToString.h"
#include "mozilla/WritingModes.h"
#include "nsString.h"
#include "nsTArray.h"
#include "Units.h"
class nsIWidget;
namespace mozilla {
class ContentCacheInParent;
namespace dom {
class BrowserParent;
} // namespace dom
/**
* ContentCache stores various information of the child content.
* This class has members which are necessary both in parent process and
* content process.
*/
class ContentCache {
public:
typedef CopyableTArray<LayoutDeviceIntRect> RectArray;
typedef widget::IMENotification IMENotification;
ContentCache() = default;
protected:
// Whole text in the target
nsString mText;
// Start offset of the composition string.
Maybe<uint32_t> mCompositionStart;
enum { ePrevCharRect = 1, eNextCharRect = 0 };
struct Selection final {
// Following values are offset in "flat text".
uint32_t mAnchor;
uint32_t mFocus;
WritingMode mWritingMode;
// Character rects at previous and next character of mAnchor and mFocus.
// The reason why ContentCache needs to store each previous character of
// them is IME may query character rect of the last character of a line
// when caret is at the end of the line.
// Note that use ePrevCharRect and eNextCharRect for accessing each item.
LayoutDeviceIntRect mAnchorCharRects[2];
LayoutDeviceIntRect mFocusCharRects[2];
// Whole rect of selected text. This is empty if the selection is collapsed.
LayoutDeviceIntRect mRect;
explicit Selection(uint32_t aAnchorOffset, uint32_t aFocusOffset,
const WritingMode& aWritingMode)
: mAnchor(aAnchorOffset),
mFocus(aFocusOffset),
mWritingMode(aWritingMode) {}
void ClearRects() {
for (auto& rect : mAnchorCharRects) {
rect.SetEmpty();
}
for (auto& rect : mFocusCharRects) {
rect.SetEmpty();
}
mRect.SetEmpty();
}
bool HasRects() const {
for (auto& rect : mAnchorCharRects) {
if (!rect.IsEmpty()) {
return true;
}
}
for (auto& rect : mFocusCharRects) {
if (!rect.IsEmpty()) {
return true;
}
}
return !mRect.IsEmpty();
}
bool Collapsed() const { return mFocus == mAnchor; }
bool Reversed() const { return mFocus < mAnchor; }
uint32_t StartOffset() const { return Reversed() ? mFocus : mAnchor; }
uint32_t EndOffset() const { return Reversed() ? mAnchor : mFocus; }
uint32_t Length() const {
return Reversed() ? mAnchor - mFocus : mFocus - mAnchor;
}
LayoutDeviceIntRect StartCharRect() const {
return Reversed() ? mFocusCharRects[eNextCharRect]
: mAnchorCharRects[eNextCharRect];
}
LayoutDeviceIntRect EndCharRect() const {
return Reversed() ? mAnchorCharRects[eNextCharRect]
: mFocusCharRects[eNextCharRect];
}
friend std::ostream& operator<<(std::ostream& aStream,
const Selection& aSelection) {
aStream << "{ mAnchor=" << aSelection.mAnchor
<< ", mFocus=" << aSelection.mFocus
<< ", mWritingMode=" << ToString(aSelection.mWritingMode).c_str();
if (aSelection.HasRects()) {
if (aSelection.mAnchor > 0) {
aStream << ", mAnchorCharRects[ePrevCharRect]="
<< aSelection.mAnchorCharRects[ContentCache::ePrevCharRect];
}
aStream << ", mAnchorCharRects[eNextCharRect]="
<< aSelection.mAnchorCharRects[ContentCache::eNextCharRect];
if (aSelection.mFocus > 0) {
aStream << ", mFocusCharRects[ePrevCharRect]="
<< aSelection.mFocusCharRects[ContentCache::ePrevCharRect];
}
aStream << ", mFocusCharRects[eNextCharRect]="
<< aSelection.mFocusCharRects[ContentCache::eNextCharRect]
<< ", mRect=" << aSelection.mRect;
}
aStream << ", Reversed()=" << (aSelection.Reversed() ? "true" : "false")
<< ", StartOffset()=" << aSelection.StartOffset()
<< ", EndOffset()=" << aSelection.EndOffset()
<< ", Collapsed()=" << (aSelection.Collapsed() ? "true" : "false")
<< ", Length()=" << aSelection.Length() << " }";
return aStream;
}
private:
Selection() = default;
friend struct IPC::ParamTraits<ContentCache::Selection>;
friend struct IPC::ParamTraits<Maybe<ContentCache::Selection>>;
};
Maybe<Selection> mSelection;
bool IsSelectionValid() const {
return mSelection.isSome() && mSelection->EndOffset() <= mText.Length();
}
// Stores first char rect because Yosemite's Japanese IME sometimes tries
// to query it. If there is no text, this is caret rect.
LayoutDeviceIntRect mFirstCharRect;
struct Caret final {
uint32_t mOffset;
LayoutDeviceIntRect mRect;
explicit Caret(uint32_t aOffset, LayoutDeviceIntRect aCaretRect)
: mOffset(aOffset), mRect(aCaretRect) {}
uint32_t Offset() const { return mOffset; }
bool HasRect() const { return !mRect.IsEmpty(); }
friend std::ostream& operator<<(std::ostream& aStream,
const Caret& aCaret) {
aStream << "{ mOffset=" << aCaret.mOffset;
if (aCaret.HasRect()) {
aStream << ", mRect=" << aCaret.mRect;
}
return aStream << " }";
}
private:
Caret() = default;
friend struct IPC::ParamTraits<ContentCache::Caret>;
friend struct IPC::ParamTraits<Maybe<ContentCache::Caret>>;
};
Maybe<Caret> mCaret;
struct TextRectArray final {
uint32_t mStart;
RectArray mRects;
explicit TextRectArray(uint32_t aStartOffset) : mStart(aStartOffset) {}
bool HasRects() const { return Length() > 0; }
uint32_t StartOffset() const { return mStart; }
uint32_t EndOffset() const {
CheckedInt<uint32_t> endOffset =
CheckedInt<uint32_t>(mStart) + mRects.Length();
return endOffset.isValid() ? endOffset.value() : UINT32_MAX;
}
uint32_t Length() const { return EndOffset() - mStart; }
bool IsOffsetInRange(uint32_t aOffset) const {
return StartOffset() <= aOffset && aOffset < EndOffset();
}
bool IsRangeCompletelyInRange(uint32_t aOffset, uint32_t aLength) const {
CheckedInt<uint32_t> endOffset = CheckedInt<uint32_t>(aOffset) + aLength;
if (NS_WARN_IF(!endOffset.isValid())) {
return false;
}
return IsOffsetInRange(aOffset) && aOffset + aLength <= EndOffset();
}
bool IsOverlappingWith(uint32_t aOffset, uint32_t aLength) const {
if (!HasRects() || aOffset == UINT32_MAX || !aLength) {
return false;
}
CheckedInt<uint32_t> endOffset = CheckedInt<uint32_t>(aOffset) + aLength;
if (NS_WARN_IF(!endOffset.isValid())) {
return false;
}
return aOffset < EndOffset() && endOffset.value() > mStart;
}
LayoutDeviceIntRect GetRect(uint32_t aOffset) const;
LayoutDeviceIntRect GetUnionRect(uint32_t aOffset, uint32_t aLength) const;
LayoutDeviceIntRect GetUnionRectAsFarAsPossible(
uint32_t aOffset, uint32_t aLength, bool aRoundToExistingOffset) const;
friend std::ostream& operator<<(std::ostream& aStream,
const TextRectArray& aTextRectArray) {
aStream << "{ mStart=" << aTextRectArray.mStart
<< ", mRects={ Length()=" << aTextRectArray.Length();
if (aTextRectArray.HasRects()) {
aStream << ", Elements()=[ ";
static constexpr uint32_t kMaxPrintRects = 4;
const uint32_t kFirstHalf = aTextRectArray.Length() <= kMaxPrintRects
? UINT32_MAX
: (kMaxPrintRects + 1) / 2;
const uint32_t kSecondHalf =
aTextRectArray.Length() <= kMaxPrintRects ? 0 : kMaxPrintRects / 2;
for (uint32_t i = 0; i < aTextRectArray.Length(); i++) {
if (i > 0) {
aStream << ", ";
}
aStream << ToString(aTextRectArray.mRects[i]).c_str();
if (i + 1 == kFirstHalf) {
aStream << " ...";
i = aTextRectArray.Length() - kSecondHalf - 1;
}
}
}
return aStream << " ] } }";
}
private:
TextRectArray() = default;
friend struct IPC::ParamTraits<ContentCache::TextRectArray>;
friend struct IPC::ParamTraits<Maybe<ContentCache::TextRectArray>>;
};
Maybe<TextRectArray> mTextRectArray;
Maybe<TextRectArray> mLastCommitStringTextRectArray;
LayoutDeviceIntRect mEditorRect;
friend class ContentCacheInParent;
friend struct IPC::ParamTraits<ContentCache>;
friend struct IPC::ParamTraits<ContentCache::Selection>;
friend struct IPC::ParamTraits<ContentCache::Caret>;
friend struct IPC::ParamTraits<ContentCache::TextRectArray>;
friend std::ostream& operator<<(
std::ostream& aStream,
const Selection& aSelection); // For e(Prev|Next)CharRect
};
class ContentCacheInChild final : public ContentCache {
public:
ContentCacheInChild() = default;
/**
* Called when composition event will be dispatched in this process from
* PuppetWidget.
*/
void OnCompositionEvent(const WidgetCompositionEvent& aCompositionEvent);
/**
* When IME loses focus, this should be called and making this forget the
* content for reducing footprint.
*/
void Clear();
/**
* Cache*() retrieves the latest content information and store them.
* Be aware, CacheSelection() calls CacheTextRects(), and also CacheText()
* calls CacheSelection(). So, related data is also retrieved automatically.
*/
bool CacheEditorRect(nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
bool CacheSelection(nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
bool CacheText(nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
bool CacheAll(nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
/**
* SetSelection() modifies selection with specified raw data. And also this
* tries to retrieve text rects too.
*/
void SetSelection(nsIWidget* aWidget, uint32_t aStartOffset, uint32_t aLength,
bool aReversed, const WritingMode& aWritingMode);
private:
bool QueryCharRect(nsIWidget* aWidget, uint32_t aOffset,
LayoutDeviceIntRect& aCharRect) const;
bool QueryCharRectArray(nsIWidget* aWidget, uint32_t aOffset,
uint32_t aLength, RectArray& aCharRectArray) const;
bool CacheCaret(nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
bool CacheTextRects(nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
// Once composition is committed, all of the commit string may be composed
// again by Kakutei-Undo of Japanese IME. Therefore, we need to keep
// storing the last composition start to cache all character rects of the
// last commit string.
Maybe<OffsetAndData<uint32_t>> mLastCommit;
};
class ContentCacheInParent final : public ContentCache {
public:
explicit ContentCacheInParent(dom::BrowserParent& aBrowserParent);
/**
* AssignContent() is called when BrowserParent receives ContentCache from
* the content process. This doesn't copy composition information because
* it's managed by BrowserParent itself.
*/
void AssignContent(const ContentCache& aOther, nsIWidget* aWidget,
const IMENotification* aNotification = nullptr);
/**
* HandleQueryContentEvent() sets content data to aEvent.mReply.
*
* For eQuerySelectedText, fail if the cache doesn't contain the whole
* selected range. (This shouldn't happen because PuppetWidget should have
* already sent the whole selection.)
*
* For eQueryTextContent, fail only if the cache doesn't overlap with
* the queried range. Note the difference from above. We use
* this behavior because a normal eQueryTextContent event is allowed to
* have out-of-bounds offsets, so that widget can request content without
* knowing the exact length of text. It's up to widget to handle cases when
* the returned offset/length are different from the queried offset/length.
*
* For eQueryTextRect, fail if cached offset/length aren't equals to input.
* Cocoa widget always queries selected offset, so it works on it.
*
* For eQueryCaretRect, fail if cached offset isn't equals to input
*
* For eQueryEditorRect, always success
*/
bool HandleQueryContentEvent(WidgetQueryContentEvent& aEvent,
nsIWidget* aWidget) const;
/**
* OnCompositionEvent() should be called before sending composition string.
* This returns true if the event should be sent. Otherwise, false.
*/
bool OnCompositionEvent(const WidgetCompositionEvent& aCompositionEvent);
/**
* OnSelectionEvent() should be called before sending selection event.
*/
void OnSelectionEvent(const WidgetSelectionEvent& aSelectionEvent);
/**
* OnEventNeedingAckHandled() should be called after the child process
* handles a sent event which needs acknowledging.
*
* WARNING: This may send notifications to IME. That might cause destroying
* BrowserParent or aWidget. Therefore, the caller must not destroy
* this instance during a call of this method.
*/
void OnEventNeedingAckHandled(nsIWidget* aWidget, EventMessage aMessage);
/**
* RequestIMEToCommitComposition() requests aWidget to commit or cancel
* composition. If it's handled synchronously, this returns true.
*
* @param aWidget The widget to be requested to commit or cancel
* the composition.
* @param aCancel When the caller tries to cancel the composition, true.
* Otherwise, i.e., tries to commit the composition, false.
* @param aCommittedString The committed string (i.e., the last data of
* dispatched composition events during requesting
* IME to commit composition.
* @return Whether the composition is actually committed
* synchronously.
*/
bool RequestIMEToCommitComposition(nsIWidget* aWidget, bool aCancel,
nsAString& aCommittedString);
/**
* MaybeNotifyIME() may notify IME of the notification. If child process
* hasn't been handled all sending events yet, this stores the notification
* and flush it later.
*/
void MaybeNotifyIME(nsIWidget* aWidget, const IMENotification& aNotification);
private:
IMENotification mPendingSelectionChange;
IMENotification mPendingTextChange;
IMENotification mPendingLayoutChange;
IMENotification mPendingCompositionUpdate;
#if MOZ_DIAGNOSTIC_ASSERT_ENABLED
// Log of event messages to be output to crash report.
nsTArray<EventMessage> mDispatchedEventMessages;
nsTArray<EventMessage> mReceivedEventMessages;
// Log of RequestIMEToCommitComposition() in the last 2 compositions.
enum class RequestIMEToCommitCompositionResult : uint8_t {
eToOldCompositionReceived,
eToCommittedCompositionReceived,
eReceivedAfterBrowserParentBlur,
eReceivedButNoTextComposition,
eHandledAsynchronously,
eHandledSynchronously,
};
const char* ToReadableText(
RequestIMEToCommitCompositionResult aResult) const {
switch (aResult) {
case RequestIMEToCommitCompositionResult::eToOldCompositionReceived:
return "Commit request is not handled because it's for "
"older composition";
case RequestIMEToCommitCompositionResult::eToCommittedCompositionReceived:
return "Commit request is not handled because BrowserParent has "
"already "
"sent commit event for the composition";
case RequestIMEToCommitCompositionResult::eReceivedAfterBrowserParentBlur:
return "Commit request is handled with stored composition string "
"because BrowserParent has already lost focus";
case RequestIMEToCommitCompositionResult::eReceivedButNoTextComposition:
return "Commit request is not handled because there is no "
"TextCompsition instance";
case RequestIMEToCommitCompositionResult::eHandledAsynchronously:
return "Commit request is handled but IME doesn't commit current "
"composition synchronously";
case RequestIMEToCommitCompositionResult::eHandledSynchronously:
return "Commit reqeust is handled synchronously";
default:
return "Unknown reason";
}
}
nsTArray<RequestIMEToCommitCompositionResult>
mRequestIMEToCommitCompositionResults;
#endif // MOZ_DIAGNOSTIC_ASSERT_ENABLED
// mBrowserParent is owner of the instance.
dom::BrowserParent& MOZ_NON_OWNING_REF mBrowserParent;
// mCompositionString is composition string which were sent to the remote
// process but not yet committed in the remote process.
nsString mCompositionString;
// This is not nullptr only while the instance is requesting IME to
// composition. Then, data value of dispatched composition events should
// be stored into the instance.
nsAString* mCommitStringByRequest;
// mPendingEventsNeedingAck is increased before sending a composition event or
// a selection event and decreased after they are received in the child
// process.
uint32_t mPendingEventsNeedingAck;
// mCompositionStartInChild stores current composition start offset in the
// remote process.
Maybe<uint32_t> mCompositionStartInChild;
// mPendingCommitLength is commit string length of the first pending
// composition. This is used by relative offset query events when querying
// new composition start offset.
// Note that when mPendingCompositionCount is not 0, i.e., there are 2 or
// more pending compositions, this cache won't be used because in such case,
// anyway ContentCacheInParent cannot return proper character rect.
uint32_t mPendingCommitLength;
// mPendingCompositionCount is number of compositions which started in widget
// but not yet handled in the child process.
uint8_t mPendingCompositionCount;
// mPendingCommitCount is number of eCompositionCommit(AsIs) events which
// were sent to the child process but not yet handled in it.
uint8_t mPendingCommitCount;
// mWidgetHasComposition is true when the widget in this process thinks that
// IME has composition. So, this is set to true when eCompositionStart is
// dispatched and set to false when eCompositionCommit(AsIs) is dispatched.
bool mWidgetHasComposition;
// mIsChildIgnoringCompositionEvents is set to true if the child process
// requests commit composition whose commit has already been sent to it.
// Then, set to false when the child process ignores the commit event.
bool mIsChildIgnoringCompositionEvents;
ContentCacheInParent() = delete;
/**
* When following methods' aRoundToExistingOffset is true, even if specified
* offset or range is out of bounds, the result is computed with the existing
* cache forcibly.
*/
bool GetCaretRect(uint32_t aOffset, bool aRoundToExistingOffset,
LayoutDeviceIntRect& aCaretRect) const;
bool GetTextRect(uint32_t aOffset, bool aRoundToExistingOffset,
LayoutDeviceIntRect& aTextRect) const;
bool GetUnionTextRects(uint32_t aOffset, uint32_t aLength,
bool aRoundToExistingOffset,
LayoutDeviceIntRect& aUnionTextRect) const;
void FlushPendingNotifications(nsIWidget* aWidget);
#if MOZ_DIAGNOSTIC_ASSERT_ENABLED
/**
* Remove unnecessary messages from mDispatchedEventMessages and
* mReceivedEventMessages.
*/
void RemoveUnnecessaryEventMessageLog();
/**
* Append event message log to aLog.
*/
void AppendEventMessageLog(nsACString& aLog) const;
#endif // #if MOZ_DIAGNOSTIC_ASSERT_ENABLED
};
} // namespace mozilla
#endif // mozilla_ContentCache_h