+ * + *
limitof a sequence of characters is the position just after their + * last character, i.e., one more than that position.
+ *
+ * Some of the API functions provide access to runs
.
+ * Such a run
is defined as a sequence of characters
+ * that are at the same embedding level
+ * after performing the BIDI algorithm.
+ * + * @author Markus W. Scherer. Ported to Mozilla by Simon Montagu + * @version 1.0 + */ + +/** + * nsBidiLevel is the type of the level values in this + * Bidi implementation. + * It holds an embedding level and indicates the visual direction + * by its bit 0 (even/odd value).
+ *
+ * It can also hold non-level values for the
+ * aParaLevel and aEmbeddingLevels
+ * arguments of SetPara; there:
+ *
aEmbeddingLevels[]
+ * value indicates whether the using application is
+ * specifying the level of a character to override whatever the
+ * Bidi implementation would resolve it to.aParaLevel can be set to the
+ * pseudo-level values NSBIDI_DEFAULT_LTR
+ * and NSBIDI_DEFAULT_RTL.The related constants are not real, valid level values.
+ * NSBIDI_DEFAULT_XXX can be used to specify
+ * a default for the paragraph level for
+ * when the SetPara function
+ * shall determine it but there is no
+ * strongly typed character in the input.
+ *
+ * Note that the value for
+ * Reordering can be done on a line, or on a paragraph which is
+ * then interpreted as one single line.
+ *
+ * On construction, the class is initially empty. It is assigned
+ * the Bidi properties of a paragraph by
+ * A Bidi class can be reused for as long as it is not deallocated
+ * by calling its destructor.
+ *
+ * This object can be reused for as long as it is not destroyed.
+ *
+ *
+ * This function takes a single plain text paragraph with or without
+ * externally specified embedding levels from
+ *
+ * If the entire paragraph consists of text of only one direction, then
+ * the function may not perform all the steps described by the algorithm,
+ * i.e., some levels may not be the same as if all steps were performed.
+ * This is not relevant for unidirectional text.
+ *
+ * The text must be externally split into separate paragraphs (rule P1).
+ * Paragraph separators (B) should appear at most at the very end.
+ *
+ * @param aText is a pointer to the single-paragraph text that the
+ * Bidi algorithm will be performed on
+ * (step (P1) of the algorithm is performed externally).
+ * The text must be (at least)
+ * Except for that bit, it must be
+ *
+ * Caution: A copy of this pointer, not of the levels,
+ * will be stored in the
+ * After the
+ * The
+ * In the new line object, the indexes will range from 0 to
+ *
+ * This is used after calling
+ *
+ * After line-breaking, rules (L1) and (L2) for the treatment of
+ * trailing WS and for reordering are performed on
+ * an
+ *
+ * Important: the line
+ *
+ * Note that this function may allocate memory under some
+ * circumstances, unlike
+ * This is especially useful for line-breaking on a paragraph.
+ *
+ * @param aLogicalStart is the first character of the run.
+ *
+ * @param aLogicalLimit will receive the limit of the run.
+ * The l-value that you point to here may be the
+ * same expression (variable) as the one for
+ *
+ *
+ *
+ * Example:
+ * @code
+ * int32_t i, count, logicalStart, visualIndex=0, length;
+ * nsBidiDirection dir;
+ * pBidi->CountRuns(&count);
+ * for(i=0; i
+ *
+ * Note that in right-to-left runs, this mapping places
+ * modifier letters before base characters and second surrogates
+ * before first ones.
+ *
+ * @param aLogicalIndex is the index of a character in the text.
+ *
+ * @param aVisualIndex will receive the visual position of this character.
+ *
+ * @see GetLogicalMap
+ * @see GetLogicalIndex
+ */
+ nsresult GetVisualIndex(int32_t aLogicalIndex, int32_t* aVisualIndex);
+
+ /**
+ * Get the logical text position from a visual position.
+ * If such a mapping is used many times on the same
+ *
+ *
+ * This is the inverse function to
+ * The index map will result in
+ *
+ * @see GetVisualMap
+ * @see GetVisualIndex
+ */
+ nsresult GetLogicalMap(int32_t *aIndexMap);
+
+ /**
+ * Get a visual-to-logical index map (array) for the characters in the nsBidi
+ * (paragraph or line) object.
+ *
+ * @param aIndexMap is a pointer to an array of
+ * The index map will result in
+ *
+ * @see GetLogicalMap
+ * @see GetLogicalIndex
+ */
+ nsresult GetVisualMap(int32_t *aIndexMap);
+
+ /**
+ * This is a convenience function that does not use a nsBidi object.
+ * It is intended to be used for when an application has determined the levels
+ * of objects (character sequences) and just needs to have them reordered (L2).
+ * This is equivalent to using
+ * The index map will result in
+ * The index map will result in NSBIDI_DEFAULT_LTR is even
+ * and the one for NSBIDI_DEFAULT_RTL is odd,
+ * just like with normal LTR and RTL level values -
+ * these special values are designed that way. Also, the implementation
+ * assumes that NSBIDI_MAX_EXPLICIT_LEVEL is odd.
+ *
+ * @see NSBIDI_DEFAULT_LTR
+ * @see NSBIDI_DEFAULT_RTL
+ * @see NSBIDI_LEVEL_OVERRIDE
+ * @see NSBIDI_MAX_EXPLICIT_LEVEL
+ */
+typedef uint8_t nsBidiLevel;
+
+/** Paragraph level setting.
+ * If there is no strong character, then set the paragraph level to 0 (left-to-right).
+ */
+#define NSBIDI_DEFAULT_LTR 0xfe
+
+/** Paragraph level setting.
+ * If there is no strong character, then set the paragraph level to 1 (right-to-left).
+ */
+#define NSBIDI_DEFAULT_RTL 0xff
+
+/**
+ * Maximum explicit embedding level.
+ * (The maximum resolved level can be up to NSBIDI_MAX_EXPLICIT_LEVEL+1).
+ *
+ */
+#define NSBIDI_MAX_EXPLICIT_LEVEL 61
+
+/** Bit flag for level input.
+ * Overrides directional properties.
+ */
+#define NSBIDI_LEVEL_OVERRIDE 0x80
+
+/**
+ * nsBidiDirection values indicate the text direction.
+ */
+enum nsBidiDirection {
+ /** All left-to-right text This is a 0 value. */
+ NSBIDI_LTR,
+ /** All right-to-left text This is a 1 value. */
+ NSBIDI_RTL,
+ /** Mixed-directional text. */
+ NSBIDI_MIXED
+};
+
+typedef enum nsBidiDirection nsBidiDirection;
+
+/* miscellaneous definitions ------------------------------------------------ */
+/** option flags for WriteReverse() */
+/**
+ * option bit for WriteReverse():
+ * keep combining characters after their base characters in RTL runs
+ *
+ * @see WriteReverse
+ */
+#define NSBIDI_KEEP_BASE_COMBINING 1
+
+/**
+ * option bit for WriteReverse():
+ * replace characters with the "mirrored" property in RTL runs
+ * by their mirror-image mappings
+ *
+ * @see WriteReverse
+ */
+#define NSBIDI_DO_MIRRORING 2
+
+/**
+ * option bit for WriteReverse():
+ * remove Bidi control characters
+ *
+ * @see WriteReverse
+ */
+#define NSBIDI_REMOVE_BIDI_CONTROLS 8
+
+/* helper macros for each allocated array member */
+#define GETDIRPROPSMEMORY(length) \
+ GetMemory((void **)&mDirPropsMemory, &mDirPropsSize, \
+ mMayAllocateText, (length))
+
+#define GETLEVELSMEMORY(length) \
+ GetMemory((void **)&mLevelsMemory, &mLevelsSize, \
+ mMayAllocateText, (length))
+
+#define GETRUNSMEMORY(length) \
+ GetMemory((void **)&mRunsMemory, &mRunsSize, \
+ mMayAllocateRuns, (length)*sizeof(Run))
+
+/* additional macros used by constructor - always allow allocation */
+#define GETINITIALDIRPROPSMEMORY(length) \
+ GetMemory((void **)&mDirPropsMemory, &mDirPropsSize, \
+ true, (length))
+
+#define GETINITIALLEVELSMEMORY(length) \
+ GetMemory((void **)&mLevelsMemory, &mLevelsSize, \
+ true, (length))
+
+#define GETINITIALRUNSMEMORY(length) \
+ GetMemory((void **)&mRunsMemory, &mRunsSize, \
+ true, (length)*sizeof(Run))
+
+/*
+ * Sometimes, bit values are more appropriate
+ * to deal with directionality properties.
+ * Abbreviations in these macro names refer to names
+ * used in the Bidi algorithm.
+ */
+typedef uint8_t DirProp;
+
+#define DIRPROP_FLAG(dir) (1UL<<(dir))
+
+/* special flag for multiple runs from explicit embedding codes */
+#define DIRPROP_FLAG_MULTI_RUNS (1UL<<31)
+
+/* are there any characters that are LTR or RTL? */
+#define MASK_LTR (DIRPROP_FLAG(L)|DIRPROP_FLAG(EN)|DIRPROP_FLAG(AN)|DIRPROP_FLAG(LRE)|DIRPROP_FLAG(LRO))
+#define MASK_RTL (DIRPROP_FLAG(R)|DIRPROP_FLAG(AL)|DIRPROP_FLAG(RLE)|DIRPROP_FLAG(RLO))
+
+/* explicit embedding codes */
+#define MASK_LRX (DIRPROP_FLAG(LRE)|DIRPROP_FLAG(LRO))
+#define MASK_RLX (DIRPROP_FLAG(RLE)|DIRPROP_FLAG(RLO))
+#define MASK_OVERRIDE (DIRPROP_FLAG(LRO)|DIRPROP_FLAG(RLO))
+
+#define MASK_EXPLICIT (MASK_LRX|MASK_RLX|DIRPROP_FLAG(PDF))
+#define MASK_BN_EXPLICIT (DIRPROP_FLAG(BN)|MASK_EXPLICIT)
+
+/* paragraph and segment separators */
+#define MASK_B_S (DIRPROP_FLAG(B)|DIRPROP_FLAG(S))
+
+/* all types that are counted as White Space or Neutral in some steps */
+#define MASK_WS (MASK_B_S|DIRPROP_FLAG(WS)|MASK_BN_EXPLICIT)
+#define MASK_N (DIRPROP_FLAG(O_N)|MASK_WS)
+
+/* all types that are included in a sequence of European Terminators for (W5) */
+#define MASK_ET_NSM_BN (DIRPROP_FLAG(ET)|DIRPROP_FLAG(NSM)|MASK_BN_EXPLICIT)
+
+/* types that are neutrals or could becomes neutrals in (Wn) */
+#define MASK_POSSIBLE_N (DIRPROP_FLAG(CS)|DIRPROP_FLAG(ES)|DIRPROP_FLAG(ET)|MASK_N)
+
+/*
+ * These types may be changed to "e",
+ * the embedding type (L or R) of the run,
+ * in the Bidi algorithm (N2)
+ */
+#define MASK_EMBEDDING (DIRPROP_FLAG(NSM)|MASK_POSSIBLE_N)
+
+/* the dirProp's L and R are defined to 0 and 1 values in nsCharType */
+#define GET_LR_FROM_LEVEL(level) ((DirProp)((level)&1))
+
+#define IS_DEFAULT_LEVEL(level) (((level)&0xfe)==0xfe)
+
+/* handle surrogate pairs --------------------------------------------------- */
+
+#define IS_FIRST_SURROGATE(uchar) (((uchar)&0xfc00)==0xd800)
+#define IS_SECOND_SURROGATE(uchar) (((uchar)&0xfc00)==0xdc00)
+
+/* get the UTF-32 value directly from the surrogate pseudo-characters */
+#define SURROGATE_OFFSET ((0xd800<<10UL)+0xdc00-0x10000)
+#define GET_UTF_32(first, second) (((first)<<10UL)+(second)-SURROGATE_OFFSET)
+
+
+#define UTF_ERROR_VALUE 0xffff
+/* definitions with forward iteration --------------------------------------- */
+
+/*
+ * all the macros that go forward assume that
+ * the initial offset is 0<=iSetPara
+ * or the Bidi properties of a line of a paragraph by
+ * SetLine.SetPara will allocate additional memory for
+ * internal structures as necessary.
+ */
+class nsBidi
+{
+public:
+ /** @brief Default constructor.
+ *
+ * The nsBidi object is initially empty. It is assigned
+ * the Bidi properties of a paragraph by SetPara()
+ * or the Bidi properties of a line of a paragraph by
+ * GetLine().SetPara() will allocate additional memory for
+ * internal structures as necessary.
+ *
+ */
+ nsBidi();
+
+ /** @brief Destructor. */
+ virtual ~nsBidi();
+
+
+ /**
+ * Perform the Unicode Bidi algorithm. It is defined in the
+ * Unicode Technical Report 9,
+ * version 5,
+ * also described in The Unicode Standard, Version 3.0 .styled
text
+ * and computes the left-right-directionality of each character.
+ * For example, in pure LTR text with numbers the numbers would get
+ * a resolved level of 2 higher than the surrounding text according to
+ * the algorithm. This implementation may set all resolved levels to
+ * the same value in such a case.aLength long.
+ *
+ * @param aLength is the length of the text; if aLength==-1 then
+ * the text must be zero-terminated.
+ *
+ * @param aParaLevel specifies the default level for the paragraph;
+ * it is typically 0 (LTR) or 1 (RTL).
+ * If the function shall determine the paragraph level from the text,
+ * then aParaLevel can be set to
+ * either NSBIDI_DEFAULT_LTR
+ * or NSBIDI_DEFAULT_RTL;
+ * if there is no strongly typed character, then
+ * the desired default is used (0 for LTR or 1 for RTL).
+ * Any other value between 0 and NSBIDI_MAX_EXPLICIT_LEVEL is also valid,
+ * with odd levels indicating RTL.
+ *
+ * @param aEmbeddingLevels (in) may be used to preset the embedding and override levels,
+ * ignoring characters like LRE and PDF in the text.
+ * A level overrides the directional property of its corresponding
+ * (same index) character if the level has the
+ * NSBIDI_LEVEL_OVERRIDE bit set.aParaLevel<=aEmbeddingLevels[]<=NSBIDI_MAX_EXPLICIT_LEVEL.nsBidi object;
+ * the aEmbeddingLevels array must not be
+ * deallocated before the nsBidi object is destroyed or reused,
+ * and the aEmbeddingLevels
+ * should not be modified to avoid unexpected results on subsequent Bidi operations.
+ * However, the SetPara and
+ * SetLine functions may modify some or all of the levels.nsBidi object is reused or destroyed, the caller
+ * must take care of the deallocation of the aEmbeddingLevels array.aEmbeddingLevels array must be
+ * at least aLength long.
+ */
+ nsresult SetPara(const char16_t *aText, int32_t aLength, nsBidiLevel aParaLevel, nsBidiLevel *aEmbeddingLevels);
+
+ /**
+ * Get the directionality of the text.
+ *
+ * @param aDirection receives a NSBIDI_XXX value that indicates if the entire text
+ * represented by this object is unidirectional,
+ * and which direction, or if it is mixed-directional.
+ *
+ * @see nsBidiDirection
+ */
+ nsresult GetDirection(nsBidiDirection* aDirection);
+
+ /**
+ * Get the paragraph level of the text.
+ *
+ * @param aParaLevel receives a NSBIDI_XXX value indicating the paragraph level
+ *
+ * @see nsBidiLevel
+ */
+ nsresult GetParaLevel(nsBidiLevel* aParaLevel);
+
+#ifdef FULL_BIDI_ENGINE
+ /**
+ * SetLine sets an nsBidi to
+ * contain the reordering information, especially the resolved levels,
+ * for all the characters in a line of text. This line of text is
+ * specified by referring to an nsBidi object representing
+ * this information for a paragraph of text, and by specifying
+ * a range of indexes in this paragraph.aLimit-aStart.SetPara
+ * for a paragraph, and after line-breaking on that paragraph.
+ * It is not necessary if the paragraph is treated as a single line.nsBidi object that represents a line.nsBidi object shares data with
+ * aParaBidi.
+ * You must destroy or reuse this object before aParaBidi.
+ * In other words, you must destroy or reuse the nsBidi object for a line
+ * before the object for its parent paragraph.
+ *
+ * @param aParaBidi is the parent paragraph object.
+ *
+ * @param aStart is the line's first index into the paragraph text.
+ *
+ * @param aLimit is just behind the line's last index into the paragraph text
+ * (its last index +1).
+ * It must be 0<=aStart<=aLimit<=paragraph length.
+ *
+ * @see SetPara
+ */
+ nsresult SetLine(nsIBidi* aParaBidi, int32_t aStart, int32_t aLimit);
+
+ /**
+ * Get the length of the text.
+ *
+ * @param aLength receives the length of the text that the nsBidi object was created for.
+ */
+ nsresult GetLength(int32_t* aLength);
+
+ /**
+ * Get the level for one character.
+ *
+ * @param aCharIndex the index of a character.
+ *
+ * @param aLevel receives the level for the character at aCharIndex.
+ *
+ * @see nsBidiLevel
+ */
+ nsresult GetLevelAt(int32_t aCharIndex, nsBidiLevel* aLevel);
+
+ /**
+ * Get an array of levels for each character.GetLevelAt.
+ *
+ * @param aLevels receives a pointer to the levels array for the text,
+ * or nullptr if an error occurs.
+ *
+ * @see nsBidiLevel
+ */
+ nsresult GetLevels(nsBidiLevel** aLevels);
+#endif // FULL_BIDI_ENGINE
+ /**
+ * Get the bidirectional type for one character.
+ *
+ * @param aCharIndex the index of a character.
+ *
+ * @param aType receives the bidirectional type of the character at aCharIndex.
+ */
+ nsresult GetCharTypeAt(int32_t aCharIndex, nsCharType* aType);
+
+ /**
+ * Get a logical run.
+ * This function returns information about a run and is used
+ * to retrieve runs in logical order.aLogicalStart.
+ * This pointer can be nullptr if this
+ * value is not necessary.
+ *
+ * @param aLevel will receive the level of the run.
+ * This pointer can be nullptr if this
+ * value is not necessary.
+ */
+ nsresult GetLogicalRun(int32_t aLogicalStart, int32_t* aLogicalLimit, nsBidiLevel* aLevel);
+
+ /**
+ * Get the number of runs.
+ * This function may invoke the actual reordering on the
+ * nsBidi object, after SetPara
+ * may have resolved only the levels of the text. Therefore,
+ * CountRuns may have to allocate memory,
+ * and may fail doing so.
+ *
+ * @param aRunCount will receive the number of runs.
+ */
+ nsresult CountRuns(int32_t* aRunCount);
+
+ /**
+ * Get one run's logical start, length, and directionality,
+ * which can be 0 for LTR or 1 for RTL.
+ * In an RTL run, the character at the logical start is
+ * visually on the right of the displayed run.
+ * The length is the number of characters in the run.CountRuns should be called
+ * before the runs are retrieved.
+ *
+ * @param aRunIndex is the number of the run in visual order, in the
+ * range [0..CountRuns-1].
+ *
+ * @param aLogicalStart is the first logical character index in the text.
+ * The pointer may be nullptr if this index is not needed.
+ *
+ * @param aLength is the number of characters (at least one) in the run.
+ * The pointer may be nullptr if this is not needed.
+ *
+ * @param aDirection will receive the directionality of the run,
+ * NSBIDI_LTR==0 or NSBIDI_RTL==1,
+ * never NSBIDI_MIXED.
+ *
+ * @see CountRunsnsBidi object, then calling
+ * GetLogicalMap is more efficient.nsBidi object, then calling
+ * GetVisualMap is more efficient.GetVisualIndex.
+ *
+ * @param aVisualIndex is the visual position of a character.
+ *
+ * @param aLogicalIndex will receive the index of this character in the text.
+ *
+ * @see GetVisualMap
+ * @see GetVisualIndex
+ */
+ nsresult GetLogicalIndex(int32_t aVisualIndex, int32_t* aLogicalIndex);
+
+ /**
+ * Get a logical-to-visual index map (array) for the characters in the nsBidi
+ * (paragraph or line) object.
+ *
+ * @param aIndexMap is a pointer to an array of GetLength
+ * indexes which will reflect the reordering of the characters.
+ * The array does not need to be initialized.aIndexMap[aLogicalIndex]==aVisualIndex.GetLength
+ * indexes which will reflect the reordering of the characters.
+ * The array does not need to be initialized.aIndexMap[aVisualIndex]==aLogicalIndex.GetLogicalMap on a
+ * nsBidi object.
+ *
+ * @param aLevels is an array with aLength levels that have been determined by
+ * the application.
+ *
+ * @param aLength is the number of levels in the array, or, semantically,
+ * the number of objects to be reordered.
+ * It must be aLength>0.
+ *
+ * @param aIndexMap is a pointer to an array of aLength
+ * indexes which will reflect the reordering of the characters.
+ * The array does not need to be initialized.aIndexMap[aLogicalIndex]==aVisualIndex.
+ */
+ static nsresult ReorderLogical(const nsBidiLevel *aLevels, int32_t aLength, int32_t *aIndexMap);
+#endif // FULL_BIDI_ENGINE
+ /**
+ * This is a convenience function that does not use a nsBidi object.
+ * It is intended to be used for when an application has determined the levels
+ * of objects (character sequences) and just needs to have them reordered (L2).
+ * This is equivalent to using GetVisualMap on a
+ * nsBidi object.
+ *
+ * @param aLevels is an array with aLength levels that have been determined by
+ * the application.
+ *
+ * @param aLength is the number of levels in the array, or, semantically,
+ * the number of objects to be reordered.
+ * It must be aLength>0.
+ *
+ * @param aIndexMap is a pointer to an array of aLength
+ * indexes which will reflect the reordering of the characters.
+ * The array does not need to be initialized.aIndexMap[aVisualIndex]==aLogicalIndex.
+ */
+ static nsresult ReorderVisual(const nsBidiLevel *aLevels, int32_t aLength, int32_t *aIndexMap);
+
+#ifdef FULL_BIDI_ENGINE
+ /**
+ * Invert an index map.
+ * The one-to-one index mapping of the first map is inverted and written to
+ * the second one.
+ *
+ * @param aSrcMap is an array with aLength indexes
+ * which define the original mapping.
+ *
+ * @param aDestMap is an array with aLength indexes
+ * which will be filled with the inverse mapping.
+ *
+ * @param aLength is the length of each array.
+ */
+ nsresult InvertMap(const int32_t *aSrcMap, int32_t *aDestMap, int32_t aLength);
+#endif // FULL_BIDI_ENGINE
+ /**
+ * Reverse a Right-To-Left run of Unicode text.
+ *
+ * This function preserves the integrity of characters with multiple
+ * code units and (optionally) modifier letters.
+ * Characters can be replaced by mirror-image characters
+ * in the destination buffer. Note that "real" mirroring has
+ * to be done in a rendering engine by glyph selection
+ * and that for many "mirrored" characters there are no
+ * Unicode characters as mirror-image equivalents.
+ * There are also options to insert or remove Bidi control
+ * characters; see the description of the aDestSize
+ * and aOptions parameters and of the option bit flags.
+ *
+ * Since no Bidi controls are inserted here, this function will never
+ * write more than aSrcLength characters to aDest.
+ *
+ * @param aSrc A pointer to the RTL run text.
+ *
+ * @param aSrcLength The length of the RTL run.
+ * If the NSBIDI_REMOVE_BIDI_CONTROLS option
+ * is set, then the destination length may be less than
+ * aSrcLength.
+ * If this option is not set, then the destination length
+ * will be exactly aSrcLength.
+ *
+ * @param aDest A pointer to where the reordered text is to be copied.
+ * aSrc[aSrcLength] and aDest[aSrcLength]
+ * must not overlap.
+ *
+ * @param aOptions A bit set of options for the reordering that control
+ * how the reordered text is written.
+ *
+ * @param aDestSize will receive the number of characters that were written to aDest.
+ */
+ nsresult WriteReverse(const char16_t *aSrc, int32_t aSrcLength, char16_t *aDest, uint16_t aOptions, int32_t *aDestSize);
+
+protected:
+ friend class nsBidiPresUtils;
+
+ /** length of the current text */
+ int32_t mLength;
+
+ /** memory sizes in bytes */
+ size_t mDirPropsSize, mLevelsSize, mRunsSize;
+
+ /** allocated memory */
+ DirProp* mDirPropsMemory;
+ nsBidiLevel* mLevelsMemory;
+ Run* mRunsMemory;
+
+ /** indicators for whether memory may be allocated after construction */
+ bool mMayAllocateText, mMayAllocateRuns;
+
+ const DirProp* mDirProps;
+ nsBidiLevel* mLevels;
+
+ /** the paragraph level */
+ nsBidiLevel mParaLevel;
+
+ /** flags is a bit set for which directional properties are in the text */
+ Flags mFlags;
+
+ /** the overall paragraph or line directionality - see nsBidiDirection */
+ nsBidiDirection mDirection;
+
+ /** characters after trailingWSStart are WS and are */
+ /* implicitly at the paraLevel (rule (L1)) - levels may not reflect that */
+ int32_t mTrailingWSStart;
+
+ /** fields for line reordering */
+ int32_t mRunCount; /* ==-1: runs not set up yet */
+ Run* mRuns;
+
+ /** for non-mixed text, we only need a tiny array of runs (no malloc()) */
+ Run mSimpleRuns[1];
+
+private:
+
+ void Init();
+
+ bool GetMemory(void **aMemory, size_t* aSize, bool aMayAllocate, size_t aSizeNeeded);
+
+ void Free();
+
+ void GetDirProps(const char16_t *aText);
+
+ nsBidiDirection ResolveExplicitLevels();
+
+ nsresult CheckExplicitLevels(nsBidiDirection *aDirection);
+
+ nsBidiDirection DirectionFromFlags(Flags aFlags);
+
+ void ResolveImplicitLevels(int32_t aStart, int32_t aLimit, DirProp aSOR, DirProp aEOR);
+
+ void AdjustWSLevels();
+
+ void SetTrailingWSStart();
+
+ bool GetRuns();
+
+ void GetSingleRun(nsBidiLevel aLevel);
+
+ void ReorderLine(nsBidiLevel aMinLevel, nsBidiLevel aMaxLevel);
+
+ static bool PrepareReorder(const nsBidiLevel *aLevels, int32_t aLength, int32_t *aIndexMap, nsBidiLevel *aMinLevel, nsBidiLevel *aMaxLevel);
+
+ int32_t doWriteReverse(const char16_t *src, int32_t srcLength,
+ char16_t *dest, uint16_t options);
+
+};
+
+#endif // _nsBidi_h_