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+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef NSTEXTRUNTRANSFORMATIONS_H_
+#define NSTEXTRUNTRANSFORMATIONS_H_
+
+#include "mozilla/Attributes.h"
+#include "mozilla/MemoryReporting.h"
+#include "mozilla/UniquePtr.h"
+#include "gfxTextRun.h"
+#include "mozilla/ComputedStyle.h"
+#include "nsPresContext.h"
+#include "nsStyleStruct.h"
+
+class nsTransformedTextRun;
+
+struct nsTransformedCharStyle final {
+ NS_INLINE_DECL_REFCOUNTING(nsTransformedCharStyle)
+
+ explicit nsTransformedCharStyle(mozilla::ComputedStyle* aStyle,
+ nsPresContext* aPresContext)
+ : mFont(aStyle->StyleFont()->mFont),
+ mLanguage(aStyle->StyleFont()->mLanguage),
+ mPresContext(aPresContext),
+ mScriptSizeMultiplier(aStyle->StyleFont()->mScriptSizeMultiplier),
+ mTextTransform(aStyle->StyleText()->mTextTransform),
+ mMathVariant(aStyle->StyleFont()->mMathVariant),
+ mExplicitLanguage(aStyle->StyleFont()->mExplicitLanguage) {}
+
+ nsFont mFont;
+ RefPtr<nsAtom> mLanguage;
+ RefPtr<nsPresContext> mPresContext;
+ float mScriptSizeMultiplier;
+ mozilla::StyleTextTransform mTextTransform;
+ mozilla::StyleMathVariant mMathVariant;
+ bool mExplicitLanguage;
+ bool mForceNonFullWidth = false;
+ bool mMaskPassword = false;
+
+ private:
+ ~nsTransformedCharStyle() = default;
+ nsTransformedCharStyle(const nsTransformedCharStyle& aOther) = delete;
+ nsTransformedCharStyle& operator=(const nsTransformedCharStyle& aOther) =
+ delete;
+};
+
+class nsTransformingTextRunFactory {
+ public:
+ virtual ~nsTransformingTextRunFactory() = default;
+
+ // Default 8-bit path just transforms to Unicode and takes that path
+ already_AddRefed<nsTransformedTextRun> MakeTextRun(
+ const uint8_t* aString, uint32_t aLength,
+ const gfxFontGroup::Parameters* aParams, gfxFontGroup* aFontGroup,
+ mozilla::gfx::ShapedTextFlags aFlags, nsTextFrameUtils::Flags aFlags2,
+ nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, bool aOwnsFactory);
+
+ already_AddRefed<nsTransformedTextRun> MakeTextRun(
+ const char16_t* aString, uint32_t aLength,
+ const gfxFontGroup::Parameters* aParams, gfxFontGroup* aFontGroup,
+ mozilla::gfx::ShapedTextFlags aFlags, nsTextFrameUtils::Flags aFlags2,
+ nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, bool aOwnsFactory);
+
+ virtual void RebuildTextRun(nsTransformedTextRun* aTextRun,
+ mozilla::gfx::DrawTarget* aRefDrawTarget,
+ gfxMissingFontRecorder* aMFR) = 0;
+};
+
+/**
+ * Builds textruns that transform the text in some way (e.g., capitalize)
+ * and then render the text using some other textrun implementation.
+ * This factory also supports "text-security" transforms that convert all
+ * characters to a single symbol.
+ */
+class nsCaseTransformTextRunFactory : public nsTransformingTextRunFactory {
+ public:
+ // We could add an optimization here so that when there is no inner
+ // factory, no title-case conversion, and no upper-casing of SZLIG, we
+ // override MakeTextRun (after making it virtual in the superclass) and have
+ // it just convert the string to uppercase or lowercase and create the textrun
+ // via the fontgroup.
+
+ // Takes ownership of aInnerTransformTextRunFactory
+ nsCaseTransformTextRunFactory(mozilla::UniquePtr<nsTransformingTextRunFactory>
+ aInnerTransformingTextRunFactory,
+ bool aAllUppercase, char16_t aMaskChar)
+ : mInnerTransformingTextRunFactory(
+ std::move(aInnerTransformingTextRunFactory)),
+ mAllUppercase(aAllUppercase),
+ mMaskChar(aMaskChar) {}
+
+ virtual void RebuildTextRun(nsTransformedTextRun* aTextRun,
+ mozilla::gfx::DrawTarget* aRefDrawTarget,
+ gfxMissingFontRecorder* aMFR) override;
+
+ // Perform a transformation on the given string, writing the result into
+ // aConvertedString. If aGlobalTransform is passed, the transform is global
+ // and aLanguage is used to determine any language-specific behavior;
+ // otherwise, an nsTransformedTextRun should be passed in as aTextRun and its
+ // styles will be used to determine the transform(s) to be applied.
+ // If such an input textrun is provided, then its line-breaks and styles
+ // will be copied to the output arrays, which must also be provided by
+ // the caller. For the global transform usage (no input textrun), these are
+ // ignored.
+ // If aMaskChar is non-zero, it is used as a "masking" character to replace
+ // all characters in the text (for -webkit-text-security).
+ // If aCaseTransformsOnly is true, then only the upper/lower/capitalize
+ // transformations are performed; full-width and full-size-kana are ignored.
+ // If `aTextRun` is not nullptr and characters which are styled with setting
+ // `nsTransformedCharStyle::mMaskPassword` to true, they are replaced with
+ // password mask characters and are not transformed (i.e., won't be added
+ // or merged for the specified transform). However, unmasked characters
+ // whose `nsTransformedCharStyle::mMaskPassword` is set to false are
+ // transformed normally.
+ // Note that "masking" behavior may be triggered either by
+ // -webkit-text-security, resulting in a non-zero aMaskChar being passed,
+ // or by <input type=password>, which results in the editor code setting
+ // nsTransformedCharStyle::mMaskPassword. (The latter mechanism enables the
+ // editor to temporarily reveal the just-entered character during typing,
+ // whereas simply setting aMaskChar would unconditionally mask all the text.)
+ static bool TransformString(
+ const nsAString& aString, nsString& aConvertedString,
+ const mozilla::Maybe<mozilla::StyleTextTransform>& aGlobalTransform,
+ char16_t aMaskChar, bool aCaseTransformsOnly, const nsAtom* aLanguage,
+ nsTArray<bool>& aCharsToMergeArray, nsTArray<bool>& aDeletedCharsArray,
+ const nsTransformedTextRun* aTextRun = nullptr,
+ uint32_t aOffsetInTextRun = 0,
+ nsTArray<uint8_t>* aCanBreakBeforeArray = nullptr,
+ nsTArray<RefPtr<nsTransformedCharStyle>>* aStyleArray = nullptr);
+
+ protected:
+ mozilla::UniquePtr<nsTransformingTextRunFactory>
+ mInnerTransformingTextRunFactory;
+ bool mAllUppercase;
+ char16_t mMaskChar;
+};
+
+/**
+ * So that we can reshape as necessary, we store enough information
+ * to fully rebuild the textrun contents.
+ */
+class nsTransformedTextRun final : public gfxTextRun {
+ public:
+ static already_AddRefed<nsTransformedTextRun> Create(
+ const gfxTextRunFactory::Parameters* aParams,
+ nsTransformingTextRunFactory* aFactory, gfxFontGroup* aFontGroup,
+ const char16_t* aString, uint32_t aLength,
+ const mozilla::gfx::ShapedTextFlags aFlags,
+ const nsTextFrameUtils::Flags aFlags2,
+ nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles, bool aOwnsFactory);
+
+ ~nsTransformedTextRun() {
+ if (mOwnsFactory) {
+ delete mFactory;
+ }
+ }
+
+ void SetCapitalization(uint32_t aStart, uint32_t aLength,
+ bool* aCapitalization);
+ virtual bool SetPotentialLineBreaks(Range aRange,
+ const uint8_t* aBreakBefore) override;
+ /**
+ * Called after SetCapitalization and SetPotentialLineBreaks
+ * are done and before we request any data from the textrun. Also always
+ * called after a Create.
+ */
+ void FinishSettingProperties(mozilla::gfx::DrawTarget* aRefDrawTarget,
+ gfxMissingFontRecorder* aMFR) {
+ if (mNeedsRebuild) {
+ mNeedsRebuild = false;
+ mFactory->RebuildTextRun(this, aRefDrawTarget, aMFR);
+ }
+ }
+
+ // override the gfxTextRun impls to account for additional members here
+ virtual size_t SizeOfExcludingThis(
+ mozilla::MallocSizeOf aMallocSizeOf) override;
+ virtual size_t SizeOfIncludingThis(
+ mozilla::MallocSizeOf aMallocSizeOf) override;
+
+ nsTransformingTextRunFactory* mFactory;
+ nsTArray<RefPtr<nsTransformedCharStyle>> mStyles;
+ nsTArray<bool> mCapitalize;
+ nsString mString;
+ bool mOwnsFactory;
+ bool mNeedsRebuild;
+
+ private:
+ nsTransformedTextRun(const gfxTextRunFactory::Parameters* aParams,
+ nsTransformingTextRunFactory* aFactory,
+ gfxFontGroup* aFontGroup, const char16_t* aString,
+ uint32_t aLength,
+ const mozilla::gfx::ShapedTextFlags aFlags,
+ const nsTextFrameUtils::Flags aFlags2,
+ nsTArray<RefPtr<nsTransformedCharStyle>>&& aStyles,
+ bool aOwnsFactory)
+ : gfxTextRun(aParams, aLength, aFontGroup, aFlags, aFlags2),
+ mFactory(aFactory),
+ mStyles(std::move(aStyles)),
+ mString(aString, aLength),
+ mOwnsFactory(aOwnsFactory),
+ mNeedsRebuild(true) {
+ mCharacterGlyphs = reinterpret_cast<CompressedGlyph*>(this + 1);
+ }
+};
+
+/**
+ * Copy a given textrun, but merge certain characters into a single logical
+ * character. Glyphs for a character are added to the glyph list for the
+ * previous character and then the merged character is eliminated. Visually the
+ * results are identical.
+ *
+ * This is used for text-transform:uppercase when we encounter a SZLIG,
+ * whose uppercase form is "SS", or other ligature or precomposed form
+ * that expands to multiple codepoints during case transformation,
+ * and for Greek text when combining diacritics have been deleted.
+ *
+ * This function is unable to merge characters when they occur in different
+ * glyph runs. This only happens in tricky edge cases where a character was
+ * decomposed by case-mapping (e.g. there's no precomposed uppercase version
+ * of an accented lowercase letter), and then font-matching caused the
+ * diacritics to be assigned to a different font than the base character.
+ * In this situation, the diacritic(s) get discarded, which is less than
+ * ideal, but they probably weren't going to render very well anyway.
+ * Bug 543200 will improve this by making font-matching operate on entire
+ * clusters instead of individual codepoints.
+ *
+ * For simplicity, this produces a textrun containing all DetailedGlyphs,
+ * no simple glyphs. So don't call it unless you really have merging to do.
+ *
+ * @param aCharsToMerge when aCharsToMerge[i] is true, this character in aSrc
+ * is merged into the previous character
+ *
+ * @param aDeletedChars when aDeletedChars[i] is true, the character at this
+ * position in aDest was deleted (has no corresponding char in aSrc)
+ */
+void MergeCharactersInTextRun(gfxTextRun* aDest, gfxTextRun* aSrc,
+ const bool* aCharsToMerge,
+ const bool* aDeletedChars);
+
+gfxTextRunFactory::Parameters GetParametersForInner(
+ nsTransformedTextRun* aTextRun, mozilla::gfx::ShapedTextFlags* aFlags,
+ mozilla::gfx::DrawTarget* aRefDrawTarget);
+
+#endif /*NSTEXTRUNTRANSFORMATIONS_H_*/