/* ****************************************************************************** * * Copyright (C) 1999-2008, International Business Machines * Corporation and others. All Rights Reserved. * ****************************************************************************** * file name: ubidi.h * encoding: US-ASCII * tab size: 8 (not used) * indentation:4 * * created on: 1999jul27 * created by: Markus W. Scherer, updated by Matitiahu Allouche */ #ifndef UBIDI_H #define UBIDI_H #include "unicode/utypes.h" #include "unicode/uchar.h" /** *\file * \brief C API: Bidi algorithm * * <h2>Bidi algorithm for ICU</h2> * * This is an implementation of the Unicode Bidirectional algorithm. * The algorithm is defined in the * <a href="http://www.unicode.org/unicode/reports/tr9/">Unicode Standard Annex #9</a>, * version 13, also described in The Unicode Standard, Version 4.0 .<p> * * Note: Libraries that perform a bidirectional algorithm and * reorder strings accordingly are sometimes called "Storage Layout Engines". * ICU's Bidi and shaping (u_shapeArabic()) APIs can be used at the core of such * "Storage Layout Engines". * * <h3>General remarks about the API:</h3> * * In functions with an error code parameter, * the <code>pErrorCode</code> pointer must be valid * and the value that it points to must not indicate a failure before * the function call. Otherwise, the function returns immediately. * After the function call, the value indicates success or failure.<p> * * The "limit" of a sequence of characters is the position just after their * last character, i.e., one more than that position.<p> * * 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.<p> * * @author Markus W. Scherer * @version 1.0 * * * <h4> Sample code for the ICU Bidi API </h4> * * <h5>Rendering a paragraph with the ICU Bidi API</h5> * * This is (hypothetical) sample code that illustrates * how the ICU Bidi API could be used to render a paragraph of text. * Rendering code depends highly on the graphics system, * therefore this sample code must make a lot of assumptions, * which may or may not match any existing graphics system's properties. * * <p>The basic assumptions are:</p> * <ul> * <li>Rendering is done from left to right on a horizontal line.</li> * <li>A run of single-style, unidirectional text can be rendered at once.</li> * <li>Such a run of text is passed to the graphics system with * characters (code units) in logical order.</li> * <li>The line-breaking algorithm is very complicated * and Locale-dependent - * and therefore its implementation omitted from this sample code.</li> * </ul> * * <pre> * \code *#include "unicode/ubidi.h" * *typedef enum { * styleNormal=0, styleSelected=1, * styleBold=2, styleItalics=4, * styleSuper=8, styleSub=16 *} Style; * *typedef struct { int32_t limit; Style style; } StyleRun; * *int getTextWidth(const UChar *text, int32_t start, int32_t limit, * const StyleRun *styleRuns, int styleRunCount); * * // set *pLimit and *pStyleRunLimit for a line * // from text[start] and from styleRuns[styleRunStart] * // using ubidi_getLogicalRun(para, ...) *void getLineBreak(const UChar *text, int32_t start, int32_t *pLimit, * UBiDi *para, * const StyleRun *styleRuns, int styleRunStart, int *pStyleRunLimit, * int *pLineWidth); * * // render runs on a line sequentially, always from left to right * * // prepare rendering a new line * void startLine(UBiDiDirection textDirection, int lineWidth); * * // render a run of text and advance to the right by the run width * // the text[start..limit-1] is always in logical order * void renderRun(const UChar *text, int32_t start, int32_t limit, * UBiDiDirection textDirection, Style style); * * // We could compute a cross-product * // from the style runs with the directional runs * // and then reorder it. * // Instead, here we iterate over each run type * // and render the intersections - * // with shortcuts in simple (and common) cases. * // renderParagraph() is the main function. * * // render a directional run with * // (possibly) multiple style runs intersecting with it * void renderDirectionalRun(const UChar *text, * int32_t start, int32_t limit, * UBiDiDirection direction, * const StyleRun *styleRuns, int styleRunCount) { * int i; * * // iterate over style runs * if(direction==UBIDI_LTR) { * int styleLimit; * * for(i=0; i<styleRunCount; ++i) { * styleLimit=styleRun[i].limit; * if(start<styleLimit) { * if(styleLimit>limit) { styleLimit=limit; } * renderRun(text, start, styleLimit, * direction, styleRun[i].style); * if(styleLimit==limit) { break; } * start=styleLimit; * } * } * } else { * int styleStart; * * for(i=styleRunCount-1; i>=0; --i) { * if(i>0) { * styleStart=styleRun[i-1].limit; * } else { * styleStart=0; * } * if(limit>=styleStart) { * if(styleStart<start) { styleStart=start; } * renderRun(text, styleStart, limit, * direction, styleRun[i].style); * if(styleStart==start) { break; } * limit=styleStart; * } * } * } * } * * // the line object represents text[start..limit-1] * void renderLine(UBiDi *line, const UChar *text, * int32_t start, int32_t limit, * const StyleRun *styleRuns, int styleRunCount) { * UBiDiDirection direction=ubidi_getDirection(line); * if(direction!=UBIDI_MIXED) { * // unidirectional * if(styleRunCount<=1) { * renderRun(text, start, limit, direction, styleRuns[0].style); * } else { * renderDirectionalRun(text, start, limit, * direction, styleRuns, styleRunCount); * } * } else { * // mixed-directional * int32_t count, i, length; * UBiDiLevel level; * * count=ubidi_countRuns(para, pErrorCode); * if(U_SUCCESS(*pErrorCode)) { * if(styleRunCount<=1) { * Style style=styleRuns[0].style; * * // iterate over directional runs * for(i=0; i<count; ++i) { * direction=ubidi_getVisualRun(para, i, &start, &length); * renderRun(text, start, start+length, direction, style); * } * } else { * int32_t j; * * // iterate over both directional and style runs * for(i=0; i<count; ++i) { * direction=ubidi_getVisualRun(line, i, &start, &length); * renderDirectionalRun(text, start, start+length, * direction, styleRuns, styleRunCount); * } * } * } * } * } * *void renderParagraph(const UChar *text, int32_t length, * UBiDiDirection textDirection, * const StyleRun *styleRuns, int styleRunCount, * int lineWidth, * UErrorCode *pErrorCode) { * UBiDi *para; * * if(pErrorCode==NULL || U_FAILURE(*pErrorCode) || length<=0) { * return; * } * * para=ubidi_openSized(length, 0, pErrorCode); * if(para==NULL) { return; } * * ubidi_setPara(para, text, length, * textDirection ? UBIDI_DEFAULT_RTL : UBIDI_DEFAULT_LTR, * NULL, pErrorCode); * if(U_SUCCESS(*pErrorCode)) { * UBiDiLevel paraLevel=1&ubidi_getParaLevel(para); * StyleRun styleRun={ length, styleNormal }; * int width; * * if(styleRuns==NULL || styleRunCount<=0) { * styleRunCount=1; * styleRuns=&styleRun; * } * * // assume styleRuns[styleRunCount-1].limit>=length * * width=getTextWidth(text, 0, length, styleRuns, styleRunCount); * if(width<=lineWidth) { * // everything fits onto one line * * // prepare rendering a new line from either left or right * startLine(paraLevel, width); * * renderLine(para, text, 0, length, * styleRuns, styleRunCount); * } else { * UBiDi *line; * * // we need to render several lines * line=ubidi_openSized(length, 0, pErrorCode); * if(line!=NULL) { * int32_t start=0, limit; * int styleRunStart=0, styleRunLimit; * * for(;;) { * limit=length; * styleRunLimit=styleRunCount; * getLineBreak(text, start, &limit, para, * styleRuns, styleRunStart, &styleRunLimit, * &width); * ubidi_setLine(para, start, limit, line, pErrorCode); * if(U_SUCCESS(*pErrorCode)) { * // prepare rendering a new line * // from either left or right * startLine(paraLevel, width); * * renderLine(line, text, start, limit, * styleRuns+styleRunStart, * styleRunLimit-styleRunStart); * } * if(limit==length) { break; } * start=limit; * styleRunStart=styleRunLimit-1; * if(start>=styleRuns[styleRunStart].limit) { * ++styleRunStart; * } * } * * ubidi_close(line); * } * } * } * * ubidi_close(para); *} *\endcode * </pre> */ /*DOCXX_TAG*/ /*@{*/ /** * UBiDiLevel 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).<p> * * It can also hold non-level values for the * <code>paraLevel</code> and <code>embeddingLevels</code> * arguments of <code>ubidi_setPara()</code>; there: * <ul> * <li>bit 7 of an <code>embeddingLevels[]</code> * value indicates whether the using application is * specifying the level of a character to <i>override</i> whatever the * Bidi implementation would resolve it to.</li> * <li><code>paraLevel</code> can be set to the * pseudo-level values <code>UBIDI_DEFAULT_LTR</code> * and <code>UBIDI_DEFAULT_RTL</code>.</li> * </ul> * * @see ubidi_setPara * * <p>The related constants are not real, valid level values. * <code>UBIDI_DEFAULT_XXX</code> can be used to specify * a default for the paragraph level for * when the <code>ubidi_setPara()</code> function * shall determine it but there is no * strongly typed character in the input.<p> * * Note that the value for <code>UBIDI_DEFAULT_LTR</code> is even * and the one for <code>UBIDI_DEFAULT_RTL</code> is odd, * just like with normal LTR and RTL level values - * these special values are designed that way. Also, the implementation * assumes that UBIDI_MAX_EXPLICIT_LEVEL is odd. * * @see UBIDI_DEFAULT_LTR * @see UBIDI_DEFAULT_RTL * @see UBIDI_LEVEL_OVERRIDE * @see UBIDI_MAX_EXPLICIT_LEVEL * @stable ICU 2.0 */ typedef uint8_t UBiDiLevel; /** Paragraph level setting.<p> * * Constant indicating that the base direction depends on the first strong * directional character in the text according to the Unicode Bidirectional * Algorithm. If no strong directional character is present, * then set the paragraph level to 0 (left-to-right).<p> * * If this value is used in conjunction with reordering modes * <code>UBIDI_REORDER_INVERSE_LIKE_DIRECT</code> or * <code>UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the text to reorder * is assumed to be visual LTR, and the text after reordering is required * to be the corresponding logical string with appropriate contextual * direction. The direction of the result string will be RTL if either * the righmost or leftmost strong character of the source text is RTL * or Arabic Letter, the direction will be LTR otherwise.<p> * * If reordering option <code>UBIDI_OPTION_INSERT_MARKS</code> is set, an RLM may * be added at the beginning of the result string to ensure round trip * (that the result string, when reordered back to visual, will produce * the original source text). * @see UBIDI_REORDER_INVERSE_LIKE_DIRECT * @see UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL * @stable ICU 2.0 */ #define UBIDI_DEFAULT_LTR 0xfe /** Paragraph level setting.<p> * * Constant indicating that the base direction depends on the first strong * directional character in the text according to the Unicode Bidirectional * Algorithm. If no strong directional character is present, * then set the paragraph level to 1 (right-to-left).<p> * * If this value is used in conjunction with reordering modes * <code>UBIDI_REORDER_INVERSE_LIKE_DIRECT</code> or * <code>UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the text to reorder * is assumed to be visual LTR, and the text after reordering is required * to be the corresponding logical string with appropriate contextual * direction. The direction of the result string will be RTL if either * the righmost or leftmost strong character of the source text is RTL * or Arabic Letter, or if the text contains no strong character; * the direction will be LTR otherwise.<p> * * If reordering option <code>UBIDI_OPTION_INSERT_MARKS</code> is set, an RLM may * be added at the beginning of the result string to ensure round trip * (that the result string, when reordered back to visual, will produce * the original source text). * @see UBIDI_REORDER_INVERSE_LIKE_DIRECT * @see UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL * @stable ICU 2.0 */ #define UBIDI_DEFAULT_RTL 0xff /** * Maximum explicit embedding level. * (The maximum resolved level can be up to <code>UBIDI_MAX_EXPLICIT_LEVEL+1</code>). * @stable ICU 2.0 */ #define UBIDI_MAX_EXPLICIT_LEVEL 61 /** Bit flag for level input. * Overrides directional properties. * @stable ICU 2.0 */ #define UBIDI_LEVEL_OVERRIDE 0x80 /** * Special value which can be returned by the mapping functions when a logical * index has no corresponding visual index or vice-versa. This may happen * for the logical-to-visual mapping of a Bidi control when option * <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> is specified. This can also happen * for the visual-to-logical mapping of a Bidi mark (LRM or RLM) inserted * by option <code>#UBIDI_OPTION_INSERT_MARKS</code>. * @see ubidi_getVisualIndex * @see ubidi_getVisualMap * @see ubidi_getLogicalIndex * @see ubidi_getLogicalMap * @stable ICU 3.6 */ #define UBIDI_MAP_NOWHERE (-1) /** * <code>UBiDiDirection</code> values indicate the text direction. * @stable ICU 2.0 */ enum UBiDiDirection { /** All left-to-right text. This is a 0 value. @stable ICU 2.0 */ UBIDI_LTR, /** All right-to-left text. This is a 1 value. @stable ICU 2.0 */ UBIDI_RTL, /** Mixed-directional text. @stable ICU 2.0 */ UBIDI_MIXED }; /** @stable ICU 2.0 */ typedef enum UBiDiDirection UBiDiDirection; /** * Forward declaration of the <code>UBiDi</code> structure for the declaration of * the API functions. Its fields are implementation-specific.<p> * This structure holds information about a paragraph (or multiple paragraphs) * of text with Bidi-algorithm-related details, or about one line of * such a paragraph.<p> * Reordering can be done on a line, or on one or more paragraphs which are * then interpreted each as one single line. * @stable ICU 2.0 */ struct UBiDi; /** @stable ICU 2.0 */ typedef struct UBiDi UBiDi; /** * Allocate a <code>UBiDi</code> structure. * Such an object is initially empty. It is assigned * the Bidi properties of a piece of text containing one or more paragraphs * by <code>ubidi_setPara()</code> * or the Bidi properties of a line within a paragraph by * <code>ubidi_setLine()</code>.<p> * This object can be reused for as long as it is not deallocated * by calling <code>ubidi_close()</code>.<p> * <code>ubidi_setPara()</code> and <code>ubidi_setLine()</code> will allocate * additional memory for internal structures as necessary. * * @return An empty <code>UBiDi</code> object. * @stable ICU 2.0 */ U_STABLE UBiDi * U_EXPORT2 ubidi_open(void); /** * Allocate a <code>UBiDi</code> structure with preallocated memory * for internal structures. * This function provides a <code>UBiDi</code> object like <code>ubidi_open()</code> * with no arguments, but it also preallocates memory for internal structures * according to the sizings supplied by the caller.<p> * Subsequent functions will not allocate any more memory, and are thus * guaranteed not to fail because of lack of memory.<p> * The preallocation can be limited to some of the internal memory * by setting some values to 0 here. That means that if, e.g., * <code>maxRunCount</code> cannot be reasonably predetermined and should not * be set to <code>maxLength</code> (the only failproof value) to avoid * wasting memory, then <code>maxRunCount</code> could be set to 0 here * and the internal structures that are associated with it will be allocated * on demand, just like with <code>ubidi_open()</code>. * * @param maxLength is the maximum text or line length that internal memory * will be preallocated for. An attempt to associate this object with a * longer text will fail, unless this value is 0, which leaves the allocation * up to the implementation. * * @param maxRunCount is the maximum anticipated number of same-level runs * that internal memory will be preallocated for. An attempt to access * visual runs on an object that was not preallocated for as many runs * as the text was actually resolved to will fail, * unless this value is 0, which leaves the allocation up to the implementation.<br><br> * The number of runs depends on the actual text and maybe anywhere between * 1 and <code>maxLength</code>. It is typically small. * * @param pErrorCode must be a valid pointer to an error code value. * * @return An empty <code>UBiDi</code> object with preallocated memory. * @stable ICU 2.0 */ U_STABLE UBiDi * U_EXPORT2 ubidi_openSized(int32_t maxLength, int32_t maxRunCount, UErrorCode *pErrorCode); /** * <code>ubidi_close()</code> must be called to free the memory * associated with a UBiDi object.<p> * * <strong>Important: </strong> * A parent <code>UBiDi</code> object must not be destroyed or reused if * it still has children. * If a <code>UBiDi</code> object has become the <i>child</i> * of another one (its <i>parent</i>) by calling * <code>ubidi_setLine()</code>, then the child object must * be destroyed (closed) or reused (by calling * <code>ubidi_setPara()</code> or <code>ubidi_setLine()</code>) * before the parent object. * * @param pBiDi is a <code>UBiDi</code> object. * * @see ubidi_setPara * @see ubidi_setLine * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_close(UBiDi *pBiDi); /** * Modify the operation of the Bidi algorithm such that it * approximates an "inverse Bidi" algorithm. This function * must be called before <code>ubidi_setPara()</code>. * * <p>The normal operation of the Bidi algorithm as described * in the Unicode Technical Report is to take text stored in logical * (keyboard, typing) order and to determine the reordering of it for visual * rendering. * Some legacy systems store text in visual order, and for operations * with standard, Unicode-based algorithms, the text needs to be transformed * to logical order. This is effectively the inverse algorithm of the * described Bidi algorithm. Note that there is no standard algorithm for * this "inverse Bidi" and that the current implementation provides only an * approximation of "inverse Bidi".</p> * * <p>With <code>isInverse</code> set to <code>TRUE</code>, * this function changes the behavior of some of the subsequent functions * in a way that they can be used for the inverse Bidi algorithm. * Specifically, runs of text with numeric characters will be treated in a * special way and may need to be surrounded with LRM characters when they are * written in reordered sequence.</p> * * <p>Output runs should be retrieved using <code>ubidi_getVisualRun()</code>. * Since the actual input for "inverse Bidi" is visually ordered text and * <code>ubidi_getVisualRun()</code> gets the reordered runs, these are actually * the runs of the logically ordered output.</p> * * <p>Calling this function with argument <code>isInverse</code> set to * <code>TRUE</code> is equivalent to calling * <code>ubidi_setReorderingMode</code> with argument * <code>reorderingMode</code> * set to <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>.<br> * Calling this function with argument <code>isInverse</code> set to * <code>FALSE</code> is equivalent to calling * <code>ubidi_setReorderingMode</code> with argument * <code>reorderingMode</code> * set to <code>#UBIDI_REORDER_DEFAULT</code>. * * @param pBiDi is a <code>UBiDi</code> object. * * @param isInverse specifies "forward" or "inverse" Bidi operation. * * @see ubidi_setPara * @see ubidi_writeReordered * @see ubidi_setReorderingMode * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_setInverse(UBiDi *pBiDi, UBool isInverse); /** * Is this Bidi object set to perform the inverse Bidi algorithm? * <p>Note: calling this function after setting the reordering mode with * <code>ubidi_setReorderingMode</code> will return <code>TRUE</code> if the * reordering mode was set to <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>, * <code>FALSE</code> for all other values.</p> * * @param pBiDi is a <code>UBiDi</code> object. * @return TRUE if the Bidi object is set to perform the inverse Bidi algorithm * by handling numbers as L. * * @see ubidi_setInverse * @see ubidi_setReorderingMode * @stable ICU 2.0 */ U_STABLE UBool U_EXPORT2 ubidi_isInverse(UBiDi *pBiDi); /** * Specify whether block separators must be allocated level zero, * so that successive paragraphs will progress from left to right. * This function must be called before <code>ubidi_setPara()</code>. * Paragraph separators (B) may appear in the text. Setting them to level zero * means that all paragraph separators (including one possibly appearing * in the last text position) are kept in the reordered text after the text * that they follow in the source text. * When this feature is not enabled, a paragraph separator at the last * position of the text before reordering will go to the first position * of the reordered text when the paragraph level is odd. * * @param pBiDi is a <code>UBiDi</code> object. * * @param orderParagraphsLTR specifies whether paragraph separators (B) must * receive level 0, so that successive paragraphs progress from left to right. * * @see ubidi_setPara * @stable ICU 3.4 */ U_STABLE void U_EXPORT2 ubidi_orderParagraphsLTR(UBiDi *pBiDi, UBool orderParagraphsLTR); /** * Is this Bidi object set to allocate level 0 to block separators so that * successive paragraphs progress from left to right? * * @param pBiDi is a <code>UBiDi</code> object. * @return TRUE if the Bidi object is set to allocate level 0 to block * separators. * * @see ubidi_orderParagraphsLTR * @stable ICU 3.4 */ U_STABLE UBool U_EXPORT2 ubidi_isOrderParagraphsLTR(UBiDi *pBiDi); /** * <code>UBiDiReorderingMode</code> values indicate which variant of the Bidi * algorithm to use. * * @see ubidi_setReorderingMode * @stable ICU 3.6 */ typedef enum UBiDiReorderingMode { /** Regular Logical to Visual Bidi algorithm according to Unicode. * This is a 0 value. * @stable ICU 3.6 */ UBIDI_REORDER_DEFAULT = 0, /** Logical to Visual algorithm which handles numbers in a way which * mimicks the behavior of Windows XP. * @stable ICU 3.6 */ UBIDI_REORDER_NUMBERS_SPECIAL, /** Logical to Visual algorithm grouping numbers with adjacent R characters * (reversible algorithm). * @stable ICU 3.6 */ UBIDI_REORDER_GROUP_NUMBERS_WITH_R, /** Reorder runs only to transform a Logical LTR string to the Logical RTL * string with the same display, or vice-versa.<br> * If this mode is set together with option * <code>#UBIDI_OPTION_INSERT_MARKS</code>, some Bidi controls in the source * text may be removed and other controls may be added to produce the * minimum combination which has the required display. * @stable ICU 3.6 */ UBIDI_REORDER_RUNS_ONLY, /** Visual to Logical algorithm which handles numbers like L * (same algorithm as selected by <code>ubidi_setInverse(TRUE)</code>. * @see ubidi_setInverse * @stable ICU 3.6 */ UBIDI_REORDER_INVERSE_NUMBERS_AS_L, /** Visual to Logical algorithm equivalent to the regular Logical to Visual * algorithm. * @stable ICU 3.6 */ UBIDI_REORDER_INVERSE_LIKE_DIRECT, /** Inverse Bidi (Visual to Logical) algorithm for the * <code>UBIDI_REORDER_NUMBERS_SPECIAL</code> Bidi algorithm. * @stable ICU 3.6 */ UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL, /** Number of values for reordering mode. * @stable ICU 3.6 */ UBIDI_REORDER_COUNT } UBiDiReorderingMode; /** * Modify the operation of the Bidi algorithm such that it implements some * variant to the basic Bidi algorithm or approximates an "inverse Bidi" * algorithm, depending on different values of the "reordering mode". * This function must be called before <code>ubidi_setPara()</code>, and stays * in effect until called again with a different argument. * * <p>The normal operation of the Bidi algorithm as described * in the Unicode Standard Annex #9 is to take text stored in logical * (keyboard, typing) order and to determine how to reorder it for visual * rendering.</p> * * <p>With the reordering mode set to a value other than * <code>#UBIDI_REORDER_DEFAULT</code>, this function changes the behavior of * some of the subsequent functions in a way such that they implement an * inverse Bidi algorithm or some other algorithm variants.</p> * * <p>Some legacy systems store text in visual order, and for operations * with standard, Unicode-based algorithms, the text needs to be transformed * into logical order. This is effectively the inverse algorithm of the * described Bidi algorithm. Note that there is no standard algorithm for * this "inverse Bidi", so a number of variants are implemented here.</p> * * <p>In other cases, it may be desirable to emulate some variant of the * Logical to Visual algorithm (e.g. one used in MS Windows), or perform a * Logical to Logical transformation.</p> * * <ul> * <li>When the reordering mode is set to <code>#UBIDI_REORDER_DEFAULT</code>, * the standard Bidi Logical to Visual algorithm is applied.</li> * * <li>When the reordering mode is set to * <code>#UBIDI_REORDER_NUMBERS_SPECIAL</code>, * the algorithm used to perform Bidi transformations when calling * <code>ubidi_setPara</code> should approximate the algorithm used in * Microsoft Windows XP rather than strictly conform to the Unicode Bidi * algorithm. * <br> * The differences between the basic algorithm and the algorithm addressed * by this option are as follows: * <ul> * <li>Within text at an even embedding level, the sequence "123AB" * (where AB represent R or AL letters) is transformed to "123BA" by the * Unicode algorithm and to "BA123" by the Windows algorithm.</li> * <li>Arabic-Indic numbers (AN) are handled by the Windows algorithm just * like regular numbers (EN).</li> * </ul></li> * * <li>When the reordering mode is set to * <code>#UBIDI_REORDER_GROUP_NUMBERS_WITH_R</code>, * numbers located between LTR text and RTL text are associated with the RTL * text. For instance, an LTR paragraph with content "abc 123 DEF" (where * upper case letters represent RTL characters) will be transformed to * "abc FED 123" (and not "abc 123 FED"), "DEF 123 abc" will be transformed * to "123 FED abc" and "123 FED abc" will be transformed to "DEF 123 abc". * This makes the algorithm reversible and makes it useful when round trip * (from visual to logical and back to visual) must be achieved without * adding LRM characters. However, this is a variation from the standard * Unicode Bidi algorithm.<br> * The source text should not contain Bidi control characters other than LRM * or RLM.</li> * * <li>When the reordering mode is set to * <code>#UBIDI_REORDER_RUNS_ONLY</code>, * a "Logical to Logical" transformation must be performed: * <ul> * <li>If the default text level of the source text (argument <code>paraLevel</code> * in <code>ubidi_setPara</code>) is even, the source text will be handled as * LTR logical text and will be transformed to the RTL logical text which has * the same LTR visual display.</li> * <li>If the default level of the source text is odd, the source text * will be handled as RTL logical text and will be transformed to the * LTR logical text which has the same LTR visual display.</li> * </ul> * This mode may be needed when logical text which is basically Arabic or * Hebrew, with possible included numbers or phrases in English, has to be * displayed as if it had an even embedding level (this can happen if the * displaying application treats all text as if it was basically LTR). * <br> * This mode may also be needed in the reverse case, when logical text which is * basically English, with possible included phrases in Arabic or Hebrew, has to * be displayed as if it had an odd embedding level. * <br> * Both cases could be handled by adding LRE or RLE at the head of the text, * if the display subsystem supports these formatting controls. If it does not, * the problem may be handled by transforming the source text in this mode * before displaying it, so that it will be displayed properly.<br> * The source text should not contain Bidi control characters other than LRM * or RLM.</li> * * <li>When the reordering mode is set to * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>, an "inverse Bidi" algorithm * is applied. * Runs of text with numeric characters will be treated like LTR letters and * may need to be surrounded with LRM characters when they are written in * reordered sequence (the option <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> can * be used with function <code>ubidi_writeReordered</code> to this end. This * mode is equivalent to calling <code>ubidi_setInverse()</code> with * argument <code>isInverse</code> set to <code>TRUE</code>.</li> * * <li>When the reordering mode is set to * <code>#UBIDI_REORDER_INVERSE_LIKE_DIRECT</code>, the "direct" Logical to Visual * Bidi algorithm is used as an approximation of an "inverse Bidi" algorithm. * This mode is similar to mode <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> * but is closer to the regular Bidi algorithm. * <br> * For example, an LTR paragraph with the content "FED 123 456 CBA" (where * upper case represents RTL characters) will be transformed to * "ABC 456 123 DEF", as opposed to "DEF 123 456 ABC" * with mode <code>UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>.<br> * When used in conjunction with option * <code>#UBIDI_OPTION_INSERT_MARKS</code>, this mode generally * adds Bidi marks to the output significantly more sparingly than mode * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> with option * <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> in calls to * <code>ubidi_writeReordered</code>.</li> * * <li>When the reordering mode is set to * <code>#UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code>, the Logical to Visual * Bidi algorithm used in Windows XP is used as an approximation of an * "inverse Bidi" algorithm. * <br> * For example, an LTR paragraph with the content "abc FED123" (where * upper case represents RTL characters) will be transformed to * "abc 123DEF.</li> * </ul> * * <p>In all the reordering modes specifying an "inverse Bidi" algorithm * (i.e. those with a name starting with <code>UBIDI_REORDER_INVERSE</code>), * output runs should be retrieved using * <code>ubidi_getVisualRun()</code>, and the output text with * <code>ubidi_writeReordered()</code>. The caller should keep in mind that in * "inverse Bidi" modes the input is actually visually ordered text and * reordered output returned by <code>ubidi_getVisualRun()</code> or * <code>ubidi_writeReordered()</code> are actually runs or character string * of logically ordered output.<br> * For all the "inverse Bidi" modes, the source text should not contain * Bidi control characters other than LRM or RLM.</p> * * <p>Note that option <code>#UBIDI_OUTPUT_REVERSE</code> of * <code>ubidi_writeReordered</code> has no useful meaning and should not be * used in conjunction with any value of the reordering mode specifying * "inverse Bidi" or with value <code>UBIDI_REORDER_RUNS_ONLY</code>. * * @param pBiDi is a <code>UBiDi</code> object. * @param reorderingMode specifies the required variant of the Bidi algorithm. * * @see UBiDiReorderingMode * @see ubidi_setInverse * @see ubidi_setPara * @see ubidi_writeReordered * @stable ICU 3.6 */ U_STABLE void U_EXPORT2 ubidi_setReorderingMode(UBiDi *pBiDi, UBiDiReorderingMode reorderingMode); /** * What is the requested reordering mode for a given Bidi object? * * @param pBiDi is a <code>UBiDi</code> object. * @return the current reordering mode of the Bidi object * @see ubidi_setReorderingMode * @stable ICU 3.6 */ U_STABLE UBiDiReorderingMode U_EXPORT2 ubidi_getReorderingMode(UBiDi *pBiDi); /** * <code>UBiDiReorderingOption</code> values indicate which options are * specified to affect the Bidi algorithm. * * @see ubidi_setReorderingOptions * @stable ICU 3.6 */ typedef enum UBiDiReorderingOption { /** * option value for <code>ubidi_setReorderingOptions</code>: * disable all the options which can be set with this function * @see ubidi_setReorderingOptions * @stable ICU 3.6 */ UBIDI_OPTION_DEFAULT = 0, /** * option bit for <code>ubidi_setReorderingOptions</code>: * insert Bidi marks (LRM or RLM) when needed to ensure correct result of * a reordering to a Logical order * * <p>This option must be set or reset before calling * <code>ubidi_setPara</code>.</p> * * <p>This option is significant only with reordering modes which generate * a result with Logical order, specifically:</p> * <ul> * <li><code>#UBIDI_REORDER_RUNS_ONLY</code></li> * <li><code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code></li> * <li><code>#UBIDI_REORDER_INVERSE_LIKE_DIRECT</code></li> * <li><code>#UBIDI_REORDER_INVERSE_FOR_NUMBERS_SPECIAL</code></li> * </ul> * * <p>If this option is set in conjunction with reordering mode * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> or with calling * <code>ubidi_setInverse(TRUE)</code>, it implies * option <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> * in calls to function <code>ubidi_writeReordered()</code>.</p> * * <p>For other reordering modes, a minimum number of LRM or RLM characters * will be added to the source text after reordering it so as to ensure * round trip, i.e. when applying the inverse reordering mode on the * resulting logical text with removal of Bidi marks * (option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> set before calling * <code>ubidi_setPara()</code> or option <code>#UBIDI_REMOVE_BIDI_CONTROLS</code> * in <code>ubidi_writeReordered</code>), the result will be identical to the * source text in the first transformation. * * <p>This option will be ignored if specified together with option * <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>. It inhibits option * <code>UBIDI_REMOVE_BIDI_CONTROLS</code> in calls to function * <code>ubidi_writeReordered()</code> and it implies option * <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> in calls to function * <code>ubidi_writeReordered()</code> if the reordering mode is * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code>.</p> * * @see ubidi_setReorderingMode * @see ubidi_setReorderingOptions * @stable ICU 3.6 */ UBIDI_OPTION_INSERT_MARKS = 1, /** * option bit for <code>ubidi_setReorderingOptions</code>: * remove Bidi control characters * * <p>This option must be set or reset before calling * <code>ubidi_setPara</code>.</p> * * <p>This option nullifies option <code>#UBIDI_OPTION_INSERT_MARKS</code>. * It inhibits option <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code> in calls * to function <code>ubidi_writeReordered()</code> and it implies option * <code>#UBIDI_REMOVE_BIDI_CONTROLS</code> in calls to that function.</p> * * @see ubidi_setReorderingMode * @see ubidi_setReorderingOptions * @stable ICU 3.6 */ UBIDI_OPTION_REMOVE_CONTROLS = 2, /** * option bit for <code>ubidi_setReorderingOptions</code>: * process the output as part of a stream to be continued * * <p>This option must be set or reset before calling * <code>ubidi_setPara</code>.</p> * * <p>This option specifies that the caller is interested in processing large * text object in parts. * The results of the successive calls are expected to be concatenated by the * caller. Only the call for the last part will have this option bit off.</p> * * <p>When this option bit is on, <code>ubidi_setPara()</code> may process * less than the full source text in order to truncate the text at a meaningful * boundary. The caller should call <code>ubidi_getProcessedLength()</code> * immediately after calling <code>ubidi_setPara()</code> in order to * determine how much of the source text has been processed. * Source text beyond that length should be resubmitted in following calls to * <code>ubidi_setPara</code>. The processed length may be less than * the length of the source text if a character preceding the last character of * the source text constitutes a reasonable boundary (like a block separator) * for text to be continued.<br> * If the last character of the source text constitutes a reasonable * boundary, the whole text will be processed at once.<br> * If nowhere in the source text there exists * such a reasonable boundary, the processed length will be zero.<br> * The caller should check for such an occurrence and do one of the following: * <ul><li>submit a larger amount of text with a better chance to include * a reasonable boundary.</li> * <li>resubmit the same text after turning off option * <code>UBIDI_OPTION_STREAMING</code>.</li></ul> * In all cases, this option should be turned off before processing the last * part of the text.</p> * * <p>When the <code>UBIDI_OPTION_STREAMING</code> option is used, * it is recommended to call <code>ubidi_orderParagraphsLTR()</code> with * argument <code>orderParagraphsLTR</code> set to <code>TRUE</code> before * calling <code>ubidi_setPara</code> so that later paragraphs may be * concatenated to previous paragraphs on the right.</p> * * @see ubidi_setReorderingMode * @see ubidi_setReorderingOptions * @see ubidi_getProcessedLength * @see ubidi_orderParagraphsLTR * @stable ICU 3.6 */ UBIDI_OPTION_STREAMING = 4 } UBiDiReorderingOption; /** * Specify which of the reordering options * should be applied during Bidi transformations. * * @param pBiDi is a <code>UBiDi</code> object. * @param reorderingOptions is a combination of zero or more of the following * options: * <code>#UBIDI_OPTION_DEFAULT</code>, <code>#UBIDI_OPTION_INSERT_MARKS</code>, * <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>, <code>#UBIDI_OPTION_STREAMING</code>. * * @see ubidi_getReorderingOptions * @stable ICU 3.6 */ U_STABLE void U_EXPORT2 ubidi_setReorderingOptions(UBiDi *pBiDi, uint32_t reorderingOptions); /** * What are the reordering options applied to a given Bidi object? * * @param pBiDi is a <code>UBiDi</code> object. * @return the current reordering options of the Bidi object * @see ubidi_setReorderingOptions * @stable ICU 3.6 */ U_STABLE uint32_t U_EXPORT2 ubidi_getReorderingOptions(UBiDi *pBiDi); /** * Perform the Unicode Bidi algorithm. It is defined in the * <a href="http://www.unicode.org/unicode/reports/tr9/">Unicode Standard Anned #9</a>, * version 13, * also described in The Unicode Standard, Version 4.0 .<p> * * This function takes a piece of plain text containing one or more paragraphs, * with or without externally specified embedding levels from <i>styled</i> * text and computes the left-right-directionality of each character.<p> * * If the entire text is all of the same directionality, 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.<br> * 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.<p> * * The text can be composed of multiple paragraphs. Occurrence of a block * separator in the text terminates a paragraph, and whatever comes next starts * a new paragraph. The exception to this rule is when a Carriage Return (CR) * is followed by a Line Feed (LF). Both CR and LF are block separators, but * in that case, the pair of characters is considered as terminating the * preceding paragraph, and a new paragraph will be started by a character * coming after the LF. * * @param pBiDi A <code>UBiDi</code> object allocated with <code>ubidi_open()</code> * which will be set to contain the reordering information, * especially the resolved levels for all the characters in <code>text</code>. * * @param text is a pointer to the text that the Bidi algorithm will be performed on. * This pointer is stored in the UBiDi object and can be retrieved * with <code>ubidi_getText()</code>.<br> * <strong>Note:</strong> the text must be (at least) <code>length</code> long. * * @param length is the length of the text; if <code>length==-1</code> then * the text must be zero-terminated. * * @param paraLevel specifies the default level for the text; * it is typically 0 (LTR) or 1 (RTL). * If the function shall determine the paragraph level from the text, * then <code>paraLevel</code> can be set to * either <code>#UBIDI_DEFAULT_LTR</code> * or <code>#UBIDI_DEFAULT_RTL</code>; if the text contains multiple * paragraphs, the paragraph level shall be determined separately for * each paragraph; if a paragraph does not include any strongly typed * character, then the desired default is used (0 for LTR or 1 for RTL). * Any other value between 0 and <code>#UBIDI_MAX_EXPLICIT_LEVEL</code> * is also valid, with odd levels indicating RTL. * * @param embeddingLevels (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 * <code>#UBIDI_LEVEL_OVERRIDE</code> bit set.<br><br> * Except for that bit, it must be * <code>paraLevel<=embeddingLevels[]<=UBIDI_MAX_EXPLICIT_LEVEL</code>, * with one exception: a level of zero may be specified for a paragraph * separator even if <code>paraLevel>0</code> when multiple paragraphs * are submitted in the same call to <code>ubidi_setPara()</code>.<br><br> * <strong>Caution: </strong>A copy of this pointer, not of the levels, * will be stored in the <code>UBiDi</code> object; * the <code>embeddingLevels</code> array must not be * deallocated before the <code>UBiDi</code> structure is destroyed or reused, * and the <code>embeddingLevels</code> * should not be modified to avoid unexpected results on subsequent Bidi operations. * However, the <code>ubidi_setPara()</code> and * <code>ubidi_setLine()</code> functions may modify some or all of the levels.<br><br> * After the <code>UBiDi</code> object is reused or destroyed, the caller * must take care of the deallocation of the <code>embeddingLevels</code> array.<br><br> * <strong>Note:</strong> the <code>embeddingLevels</code> array must be * at least <code>length</code> long. * * @param pErrorCode must be a valid pointer to an error code value. * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_setPara(UBiDi *pBiDi, const UChar *text, int32_t length, UBiDiLevel paraLevel, UBiDiLevel *embeddingLevels, UErrorCode *pErrorCode); /** * <code>ubidi_setLine()</code> sets a <code>UBiDi</code> 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 a <code>UBiDi</code> object representing * this information for a piece of text containing one or more paragraphs, * and by specifying a range of indexes in this text.<p> * In the new line object, the indexes will range from 0 to <code>limit-start-1</code>.<p> * * This is used after calling <code>ubidi_setPara()</code> * for a piece of text, and after line-breaking on that text. * It is not necessary if each paragraph is treated as a single line.<p> * * After line-breaking, rules (L1) and (L2) for the treatment of * trailing WS and for reordering are performed on * a <code>UBiDi</code> object that represents a line.<p> * * <strong>Important: </strong><code>pLineBiDi</code> shares data with * <code>pParaBiDi</code>. * You must destroy or reuse <code>pLineBiDi</code> before <code>pParaBiDi</code>. * In other words, you must destroy or reuse the <code>UBiDi</code> object for a line * before the object for its parent paragraph.<p> * * The text pointer that was stored in <code>pParaBiDi</code> is also copied, * and <code>start</code> is added to it so that it points to the beginning of the * line for this object. * * @param pParaBiDi is the parent paragraph object. It must have been set * by a successful call to ubidi_setPara. * * @param start is the line's first index into the text. * * @param limit is just behind the line's last index into the text * (its last index +1).<br> * It must be <code>0<=start<limit<=</code>containing paragraph limit. * If the specified line crosses a paragraph boundary, the function * will terminate with error code U_ILLEGAL_ARGUMENT_ERROR. * * @param pLineBiDi is the object that will now represent a line of the text. * * @param pErrorCode must be a valid pointer to an error code value. * * @see ubidi_setPara * @see ubidi_getProcessedLength * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_setLine(const UBiDi *pParaBiDi, int32_t start, int32_t limit, UBiDi *pLineBiDi, UErrorCode *pErrorCode); /** * Get the directionality of the text. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @return a value of <code>UBIDI_LTR</code>, <code>UBIDI_RTL</code> * or <code>UBIDI_MIXED</code> * that indicates if the entire text * represented by this object is unidirectional, * and which direction, or if it is mixed-directional. * * @see UBiDiDirection * @stable ICU 2.0 */ U_STABLE UBiDiDirection U_EXPORT2 ubidi_getDirection(const UBiDi *pBiDi); /** * Get the pointer to the text. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @return The pointer to the text that the UBiDi object was created for. * * @see ubidi_setPara * @see ubidi_setLine * @stable ICU 2.0 */ U_STABLE const UChar * U_EXPORT2 ubidi_getText(const UBiDi *pBiDi); /** * Get the length of the text. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @return The length of the text that the UBiDi object was created for. * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 ubidi_getLength(const UBiDi *pBiDi); /** * Get the paragraph level of the text. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @return The paragraph level. If there are multiple paragraphs, their * level may vary if the required paraLevel is UBIDI_DEFAULT_LTR or * UBIDI_DEFAULT_RTL. In that case, the level of the first paragraph * is returned. * * @see UBiDiLevel * @see ubidi_getParagraph * @see ubidi_getParagraphByIndex * @stable ICU 2.0 */ U_STABLE UBiDiLevel U_EXPORT2 ubidi_getParaLevel(const UBiDi *pBiDi); /** * Get the number of paragraphs. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @return The number of paragraphs. * @stable ICU 3.4 */ U_STABLE int32_t U_EXPORT2 ubidi_countParagraphs(UBiDi *pBiDi); /** * Get a paragraph, given a position within the text. * This function returns information about a paragraph.<br> * Note: if the paragraph index is known, it is more efficient to * retrieve the paragraph information using ubidi_getParagraphByIndex().<p> * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param charIndex is the index of a character within the text, in the * range <code>[0..ubidi_getProcessedLength(pBiDi)-1]</code>. * * @param pParaStart will receive the index of the first character of the * paragraph in the text. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pParaLimit will receive the limit of the paragraph. * The l-value that you point to here may be the * same expression (variable) as the one for * <code>charIndex</code>. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pParaLevel will receive the level of the paragraph. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pErrorCode must be a valid pointer to an error code value. * * @return The index of the paragraph containing the specified position. * * @see ubidi_getProcessedLength * @stable ICU 3.4 */ U_STABLE int32_t U_EXPORT2 ubidi_getParagraph(const UBiDi *pBiDi, int32_t charIndex, int32_t *pParaStart, int32_t *pParaLimit, UBiDiLevel *pParaLevel, UErrorCode *pErrorCode); /** * Get a paragraph, given the index of this paragraph. * * This function returns information about a paragraph.<p> * * @param pBiDi is the paragraph <code>UBiDi</code> object. * * @param paraIndex is the number of the paragraph, in the * range <code>[0..ubidi_countParagraphs(pBiDi)-1]</code>. * * @param pParaStart will receive the index of the first character of the * paragraph in the text. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pParaLimit will receive the limit of the paragraph. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pParaLevel will receive the level of the paragraph. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pErrorCode must be a valid pointer to an error code value. * * @stable ICU 3.4 */ U_STABLE void U_EXPORT2 ubidi_getParagraphByIndex(const UBiDi *pBiDi, int32_t paraIndex, int32_t *pParaStart, int32_t *pParaLimit, UBiDiLevel *pParaLevel, UErrorCode *pErrorCode); /** * Get the level for one character. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param charIndex the index of a character. It must be in the range * [0..ubidi_getProcessedLength(pBiDi)]. * * @return The level for the character at charIndex (0 if charIndex is not * in the valid range). * * @see UBiDiLevel * @see ubidi_getProcessedLength * @stable ICU 2.0 */ U_STABLE UBiDiLevel U_EXPORT2 ubidi_getLevelAt(const UBiDi *pBiDi, int32_t charIndex); /** * Get an array of levels for each character.<p> * * Note that this function may allocate memory under some * circumstances, unlike <code>ubidi_getLevelAt()</code>. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object, whose * text length must be strictly positive. * * @param pErrorCode must be a valid pointer to an error code value. * * @return The levels array for the text, * or <code>NULL</code> if an error occurs. * * @see UBiDiLevel * @see ubidi_getProcessedLength * @stable ICU 2.0 */ U_STABLE const UBiDiLevel * U_EXPORT2 ubidi_getLevels(UBiDi *pBiDi, UErrorCode *pErrorCode); /** * Get a logical run. * This function returns information about a run and is used * to retrieve runs in logical order.<p> * This is especially useful for line-breaking on a paragraph. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param logicalPosition is a logical position within the source text. * * @param pLogicalLimit will receive the limit of the corresponding run. * The l-value that you point to here may be the * same expression (variable) as the one for * <code>logicalPosition</code>. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @param pLevel will receive the level of the corresponding run. * This pointer can be <code>NULL</code> if this * value is not necessary. * * @see ubidi_getProcessedLength * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_getLogicalRun(const UBiDi *pBiDi, int32_t logicalPosition, int32_t *pLogicalLimit, UBiDiLevel *pLevel); /** * Get the number of runs. * This function may invoke the actual reordering on the * <code>UBiDi</code> object, after <code>ubidi_setPara()</code> * may have resolved only the levels of the text. Therefore, * <code>ubidi_countRuns()</code> may have to allocate memory, * and may fail doing so. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param pErrorCode must be a valid pointer to an error code value. * * @return The number of runs. * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 ubidi_countRuns(UBiDi *pBiDi, UErrorCode *pErrorCode); /** * 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.<p> * <code>ubidi_countRuns()</code> should be called * before the runs are retrieved. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param runIndex is the number of the run in visual order, in the * range <code>[0..ubidi_countRuns(pBiDi)-1]</code>. * * @param pLogicalStart is the first logical character index in the text. * The pointer may be <code>NULL</code> if this index is not needed. * * @param pLength is the number of characters (at least one) in the run. * The pointer may be <code>NULL</code> if this is not needed. * * @return the directionality of the run, * <code>UBIDI_LTR==0</code> or <code>UBIDI_RTL==1</code>, * never <code>UBIDI_MIXED</code>. * * @see ubidi_countRuns * * Example: * <pre> * \code * int32_t i, count=ubidi_countRuns(pBiDi), * logicalStart, visualIndex=0, length; * for(i=0; i<count; ++i) { * if(UBIDI_LTR==ubidi_getVisualRun(pBiDi, i, &logicalStart, &length)) { * do { // LTR * show_char(text[logicalStart++], visualIndex++); * } while(--length>0); * } else { * logicalStart+=length; // logicalLimit * do { // RTL * show_char(text[--logicalStart], visualIndex++); * } while(--length>0); * } * } *\endcode * </pre> * * Note that in right-to-left runs, code like this places * second surrogates before first ones (which is generally a bad idea) * and combining characters before base characters. * <p> * Use of <code>ubidi_writeReordered()</code>, optionally with the * <code>#UBIDI_KEEP_BASE_COMBINING</code> option, can be considered in order * to avoid these issues. * @stable ICU 2.0 */ U_STABLE UBiDiDirection U_EXPORT2 ubidi_getVisualRun(UBiDi *pBiDi, int32_t runIndex, int32_t *pLogicalStart, int32_t *pLength); /** * Get the visual position from a logical text position. * If such a mapping is used many times on the same * <code>UBiDi</code> object, then calling * <code>ubidi_getLogicalMap()</code> is more efficient.<p> * * The value returned may be <code>#UBIDI_MAP_NOWHERE</code> if there is no * visual position because the corresponding text character is a Bidi control * removed from output by the option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>. * <p> * When the visual output is altered by using options of * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the visual position returned may not * be correct. It is advised to use, when possible, reordering options * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. * <p> * Note that in right-to-left runs, this mapping places * second surrogates before first ones (which is generally a bad idea) * and combining characters before base characters. * Use of <code>ubidi_writeReordered()</code>, optionally with the * <code>#UBIDI_KEEP_BASE_COMBINING</code> option can be considered instead * of using the mapping, in order to avoid these issues. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param logicalIndex is the index of a character in the text. * * @param pErrorCode must be a valid pointer to an error code value. * * @return The visual position of this character. * * @see ubidi_getLogicalMap * @see ubidi_getLogicalIndex * @see ubidi_getProcessedLength * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 ubidi_getVisualIndex(UBiDi *pBiDi, int32_t logicalIndex, UErrorCode *pErrorCode); /** * Get the logical text position from a visual position. * If such a mapping is used many times on the same * <code>UBiDi</code> object, then calling * <code>ubidi_getVisualMap()</code> is more efficient.<p> * * The value returned may be <code>#UBIDI_MAP_NOWHERE</code> if there is no * logical position because the corresponding text character is a Bidi mark * inserted in the output by option <code>#UBIDI_OPTION_INSERT_MARKS</code>. * <p> * This is the inverse function to <code>ubidi_getVisualIndex()</code>. * <p> * When the visual output is altered by using options of * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the logical position returned may not * be correct. It is advised to use, when possible, reordering options * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param visualIndex is the visual position of a character. * * @param pErrorCode must be a valid pointer to an error code value. * * @return The index of this character in the text. * * @see ubidi_getVisualMap * @see ubidi_getVisualIndex * @see ubidi_getResultLength * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 ubidi_getLogicalIndex(UBiDi *pBiDi, int32_t visualIndex, UErrorCode *pErrorCode); /** * Get a logical-to-visual index map (array) for the characters in the UBiDi * (paragraph or line) object. * <p> * Some values in the map may be <code>#UBIDI_MAP_NOWHERE</code> if the * corresponding text characters are Bidi controls removed from the visual * output by the option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code>. * <p> * When the visual output is altered by using options of * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the visual positions returned may not * be correct. It is advised to use, when possible, reordering options * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. * <p> * Note that in right-to-left runs, this mapping places * second surrogates before first ones (which is generally a bad idea) * and combining characters before base characters. * Use of <code>ubidi_writeReordered()</code>, optionally with the * <code>#UBIDI_KEEP_BASE_COMBINING</code> option can be considered instead * of using the mapping, in order to avoid these issues. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param indexMap is a pointer to an array of <code>ubidi_getProcessedLength()</code> * indexes which will reflect the reordering of the characters. * If option <code>#UBIDI_OPTION_INSERT_MARKS</code> is set, the number * of elements allocated in <code>indexMap</code> must be no less than * <code>ubidi_getResultLength()</code>. * The array does not need to be initialized.<br><br> * The index map will result in <code>indexMap[logicalIndex]==visualIndex</code>. * * @param pErrorCode must be a valid pointer to an error code value. * * @see ubidi_getVisualMap * @see ubidi_getVisualIndex * @see ubidi_getProcessedLength * @see ubidi_getResultLength * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_getLogicalMap(UBiDi *pBiDi, int32_t *indexMap, UErrorCode *pErrorCode); /** * Get a visual-to-logical index map (array) for the characters in the UBiDi * (paragraph or line) object. * <p> * Some values in the map may be <code>#UBIDI_MAP_NOWHERE</code> if the * corresponding text characters are Bidi marks inserted in the visual output * by the option <code>#UBIDI_OPTION_INSERT_MARKS</code>. * <p> * When the visual output is altered by using options of * <code>ubidi_writeReordered()</code> such as <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code>, * <code>UBIDI_KEEP_BASE_COMBINING</code>, <code>UBIDI_OUTPUT_REVERSE</code>, * <code>UBIDI_REMOVE_BIDI_CONTROLS</code>, the logical positions returned may not * be correct. It is advised to use, when possible, reordering options * such as <code>UBIDI_OPTION_INSERT_MARKS</code> and <code>UBIDI_OPTION_REMOVE_CONTROLS</code>. * * @param pBiDi is the paragraph or line <code>UBiDi</code> object. * * @param indexMap is a pointer to an array of <code>ubidi_getResultLength()</code> * indexes which will reflect the reordering of the characters. * If option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> is set, the number * of elements allocated in <code>indexMap</code> must be no less than * <code>ubidi_getProcessedLength()</code>. * The array does not need to be initialized.<br><br> * The index map will result in <code>indexMap[visualIndex]==logicalIndex</code>. * * @param pErrorCode must be a valid pointer to an error code value. * * @see ubidi_getLogicalMap * @see ubidi_getLogicalIndex * @see ubidi_getProcessedLength * @see ubidi_getResultLength * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_getVisualMap(UBiDi *pBiDi, int32_t *indexMap, UErrorCode *pErrorCode); /** * This is a convenience function that does not use a UBiDi 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 <code>ubidi_getLogicalMap()</code> on a * <code>UBiDi</code> object. * * @param levels is an array with <code>length</code> levels that have been determined by * the application. * * @param length is the number of levels in the array, or, semantically, * the number of objects to be reordered. * It must be <code>length>0</code>. * * @param indexMap is a pointer to an array of <code>length</code> * indexes which will reflect the reordering of the characters. * The array does not need to be initialized.<p> * The index map will result in <code>indexMap[logicalIndex]==visualIndex</code>. * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_reorderLogical(const UBiDiLevel *levels, int32_t length, int32_t *indexMap); /** * This is a convenience function that does not use a UBiDi 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 <code>ubidi_getVisualMap()</code> on a * <code>UBiDi</code> object. * * @param levels is an array with <code>length</code> levels that have been determined by * the application. * * @param length is the number of levels in the array, or, semantically, * the number of objects to be reordered. * It must be <code>length>0</code>. * * @param indexMap is a pointer to an array of <code>length</code> * indexes which will reflect the reordering of the characters. * The array does not need to be initialized.<p> * The index map will result in <code>indexMap[visualIndex]==logicalIndex</code>. * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_reorderVisual(const UBiDiLevel *levels, int32_t length, int32_t *indexMap); /** * Invert an index map. * The index mapping of the first map is inverted and written to * the second one. * * @param srcMap is an array with <code>length</code> elements * which defines the original mapping from a source array containing * <code>length</code> elements to a destination array. * Some elements of the source array may have no mapping in the * destination array. In that case, their value will be * the special value <code>UBIDI_MAP_NOWHERE</code>. * All elements must be >=0 or equal to <code>UBIDI_MAP_NOWHERE</code>. * Some elements may have a value >= <code>length</code>, if the * destination array has more elements than the source array. * There must be no duplicate indexes (two or more elements with the * same value except <code>UBIDI_MAP_NOWHERE</code>). * * @param destMap is an array with a number of elements equal to 1 + the highest * value in <code>srcMap</code>. * <code>destMap</code> will be filled with the inverse mapping. * If element with index i in <code>srcMap</code> has a value k different * from <code>UBIDI_MAP_NOWHERE</code>, this means that element i of * the source array maps to element k in the destination array. * The inverse map will have value i in its k-th element. * For all elements of the destination array which do not map to * an element in the source array, the corresponding element in the * inverse map will have a value equal to <code>UBIDI_MAP_NOWHERE</code>. * * @param length is the length of each array. * @see UBIDI_MAP_NOWHERE * @stable ICU 2.0 */ U_STABLE void U_EXPORT2 ubidi_invertMap(const int32_t *srcMap, int32_t *destMap, int32_t length); /** option flags for ubidi_writeReordered() */ /** * option bit for ubidi_writeReordered(): * keep combining characters after their base characters in RTL runs * * @see ubidi_writeReordered * @stable ICU 2.0 */ #define UBIDI_KEEP_BASE_COMBINING 1 /** * option bit for ubidi_writeReordered(): * replace characters with the "mirrored" property in RTL runs * by their mirror-image mappings * * @see ubidi_writeReordered * @stable ICU 2.0 */ #define UBIDI_DO_MIRRORING 2 /** * option bit for ubidi_writeReordered(): * surround the run with LRMs if necessary; * this is part of the approximate "inverse Bidi" algorithm * * <p>This option does not imply corresponding adjustment of the index * mappings.</p> * * @see ubidi_setInverse * @see ubidi_writeReordered * @stable ICU 2.0 */ #define UBIDI_INSERT_LRM_FOR_NUMERIC 4 /** * option bit for ubidi_writeReordered(): * remove Bidi control characters * (this does not affect #UBIDI_INSERT_LRM_FOR_NUMERIC) * * <p>This option does not imply corresponding adjustment of the index * mappings.</p> * * @see ubidi_writeReordered * @stable ICU 2.0 */ #define UBIDI_REMOVE_BIDI_CONTROLS 8 /** * option bit for ubidi_writeReordered(): * write the output in reverse order * * <p>This has the same effect as calling <code>ubidi_writeReordered()</code> * first without this option, and then calling * <code>ubidi_writeReverse()</code> without mirroring. * Doing this in the same step is faster and avoids a temporary buffer. * An example for using this option is output to a character terminal that * is designed for RTL scripts and stores text in reverse order.</p> * * @see ubidi_writeReordered * @stable ICU 2.0 */ #define UBIDI_OUTPUT_REVERSE 16 /** * Get the length of the source text processed by the last call to * <code>ubidi_setPara()</code>. This length may be different from the length * of the source text if option <code>#UBIDI_OPTION_STREAMING</code> * has been set. * <br> * Note that whenever the length of the text affects the execution or the * result of a function, it is the processed length which must be considered, * except for <code>ubidi_setPara</code> (which receives unprocessed source * text) and <code>ubidi_getLength</code> (which returns the original length * of the source text).<br> * In particular, the processed length is the one to consider in the following * cases: * <ul> * <li>maximum value of the <code>limit</code> argument of * <code>ubidi_setLine</code></li> * <li>maximum value of the <code>charIndex</code> argument of * <code>ubidi_getParagraph</code></li> * <li>maximum value of the <code>charIndex</code> argument of * <code>ubidi_getLevelAt</code></li> * <li>number of elements in the array returned by <code>ubidi_getLevels</code></li> * <li>maximum value of the <code>logicalStart</code> argument of * <code>ubidi_getLogicalRun</code></li> * <li>maximum value of the <code>logicalIndex</code> argument of * <code>ubidi_getVisualIndex</code></li> * <li>number of elements filled in the <code>*indexMap</code> argument of * <code>ubidi_getLogicalMap</code></li> * <li>length of text processed by <code>ubidi_writeReordered</code></li> * </ul> * * @param pBiDi is the paragraph <code>UBiDi</code> object. * * @return The length of the part of the source text processed by * the last call to <code>ubidi_setPara</code>. * @see ubidi_setPara * @see UBIDI_OPTION_STREAMING * @stable ICU 3.6 */ U_STABLE int32_t U_EXPORT2 ubidi_getProcessedLength(const UBiDi *pBiDi); /** * Get the length of the reordered text resulting from the last call to * <code>ubidi_setPara()</code>. This length may be different from the length * of the source text if option <code>#UBIDI_OPTION_INSERT_MARKS</code> * or option <code>#UBIDI_OPTION_REMOVE_CONTROLS</code> has been set. * <br> * This resulting length is the one to consider in the following cases: * <ul> * <li>maximum value of the <code>visualIndex</code> argument of * <code>ubidi_getLogicalIndex</code></li> * <li>number of elements of the <code>*indexMap</code> argument of * <code>ubidi_getVisualMap</code></li> * </ul> * Note that this length stays identical to the source text length if * Bidi marks are inserted or removed using option bits of * <code>ubidi_writeReordered</code>, or if option * <code>#UBIDI_REORDER_INVERSE_NUMBERS_AS_L</code> has been set. * * @param pBiDi is the paragraph <code>UBiDi</code> object. * * @return The length of the reordered text resulting from * the last call to <code>ubidi_setPara</code>. * @see ubidi_setPara * @see UBIDI_OPTION_INSERT_MARKS * @see UBIDI_OPTION_REMOVE_CONTROLS * @stable ICU 3.6 */ U_STABLE int32_t U_EXPORT2 ubidi_getResultLength(const UBiDi *pBiDi); U_CDECL_BEGIN /** * value returned by <code>UBiDiClassCallback</code> callbacks when * there is no need to override the standard Bidi class for a given code point. * @see UBiDiClassCallback * @stable ICU 3.6 */ #define U_BIDI_CLASS_DEFAULT U_CHAR_DIRECTION_COUNT /** * Callback type declaration for overriding default Bidi class values with * custom ones. * <p>Usually, the function pointer will be propagated to a <code>UBiDi</code> * object by calling the <code>ubidi_setClassCallback()</code> function; * then the callback will be invoked by the UBA implementation any time the * class of a character is to be determined.</p> * * @param context is a pointer to the callback private data. * * @param c is the code point to get a Bidi class for. * * @return The directional property / Bidi class for the given code point * <code>c</code> if the default class has been overridden, or * <code>#U_BIDI_CLASS_DEFAULT</code> if the standard Bidi class value * for <code>c</code> is to be used. * @see ubidi_setClassCallback * @see ubidi_getClassCallback * @stable ICU 3.6 */ typedef UCharDirection U_CALLCONV UBiDiClassCallback(const void *context, UChar32 c); U_CDECL_END /** * Retrieve the Bidi class for a given code point. * <p>If a <code>#UBiDiClassCallback</code> callback is defined and returns a * value other than <code>#U_BIDI_CLASS_DEFAULT</code>, that value is used; * otherwise the default class determination mechanism is invoked.</p> * * @param pBiDi is the paragraph <code>UBiDi</code> object. * * @param c is the code point whose Bidi class must be retrieved. * * @return The Bidi class for character <code>c</code> based * on the given <code>pBiDi</code> instance. * @see UBiDiClassCallback * @stable ICU 3.6 */ U_STABLE UCharDirection U_EXPORT2 ubidi_getCustomizedClass(UBiDi *pBiDi, UChar32 c); /** * Set the callback function and callback data used by the UBA * implementation for Bidi class determination. * <p>This may be useful for assigning Bidi classes to PUA characters, or * for special application needs. For instance, an application may want to * handle all spaces like L or R characters (according to the base direction) * when creating the visual ordering of logical lines which are part of a report * organized in columns: there should not be interaction between adjacent * cells.<p> * * @param pBiDi is the paragraph <code>UBiDi</code> object. * * @param newFn is the new callback function pointer. * * @param newContext is the new callback context pointer. This can be NULL. * * @param oldFn fillin: Returns the old callback function pointer. This can be * NULL. * * @param oldContext fillin: Returns the old callback's context. This can be * NULL. * * @param pErrorCode must be a valid pointer to an error code value. * * @see ubidi_getClassCallback * @stable ICU 3.6 */ U_STABLE void U_EXPORT2 ubidi_setClassCallback(UBiDi *pBiDi, UBiDiClassCallback *newFn, const void *newContext, UBiDiClassCallback **oldFn, const void **oldContext, UErrorCode *pErrorCode); /** * Get the current callback function used for Bidi class determination. * * @param pBiDi is the paragraph <code>UBiDi</code> object. * * @param fn fillin: Returns the callback function pointer. * * @param context fillin: Returns the callback's private context. * * @see ubidi_setClassCallback * @stable ICU 3.6 */ U_STABLE void U_EXPORT2 ubidi_getClassCallback(UBiDi *pBiDi, UBiDiClassCallback **fn, const void **context); /** * Take a <code>UBiDi</code> object containing the reordering * information for a piece of text (one or more paragraphs) set by * <code>ubidi_setPara()</code> or for a line of text set by * <code>ubidi_setLine()</code> and write a reordered string to the * destination buffer. * * This function preserves the integrity of characters with multiple * code units and (optionally) combining characters. * Characters in RTL runs 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 <code>destSize</code> * and <code>options</code> parameters and of the option bit flags. * * @param pBiDi A pointer to a <code>UBiDi</code> object that * is set by <code>ubidi_setPara()</code> or * <code>ubidi_setLine()</code> and contains the reordering * information for the text that it was defined for, * as well as a pointer to that text.<br><br> * The text was aliased (only the pointer was stored * without copying the contents) and must not have been modified * since the <code>ubidi_setPara()</code> call. * * @param dest A pointer to where the reordered text is to be copied. * The source text and <code>dest[destSize]</code> * must not overlap. * * @param destSize The size of the <code>dest</code> buffer, * in number of UChars. * If the <code>UBIDI_INSERT_LRM_FOR_NUMERIC</code> * option is set, then the destination length could be * as large as * <code>ubidi_getLength(pBiDi)+2*ubidi_countRuns(pBiDi)</code>. * If the <code>UBIDI_REMOVE_BIDI_CONTROLS</code> option * is set, then the destination length may be less than * <code>ubidi_getLength(pBiDi)</code>. * If none of these options is set, then the destination length * will be exactly <code>ubidi_getProcessedLength(pBiDi)</code>. * * @param options A bit set of options for the reordering that control * how the reordered text is written. * The options include mirroring the characters on a code * point basis and inserting LRM characters, which is used * especially for transforming visually stored text * to logically stored text (although this is still an * imperfect implementation of an "inverse Bidi" algorithm * because it uses the "forward Bidi" algorithm at its core). * The available options are: * <code>#UBIDI_DO_MIRRORING</code>, * <code>#UBIDI_INSERT_LRM_FOR_NUMERIC</code>, * <code>#UBIDI_KEEP_BASE_COMBINING</code>, * <code>#UBIDI_OUTPUT_REVERSE</code>, * <code>#UBIDI_REMOVE_BIDI_CONTROLS</code> * * @param pErrorCode must be a valid pointer to an error code value. * * @return The length of the output string. * * @see ubidi_getProcessedLength * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 ubidi_writeReordered(UBiDi *pBiDi, UChar *dest, int32_t destSize, uint16_t options, UErrorCode *pErrorCode); /** * Reverse a Right-To-Left run of Unicode text. * * This function preserves the integrity of characters with multiple * code units and (optionally) combining characters. * 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. * * This function is the implementation for reversing RTL runs as part * of <code>ubidi_writeReordered()</code>. For detailed descriptions * of the parameters, see there. * Since no Bidi controls are inserted here, the output string length * will never exceed <code>srcLength</code>. * * @see ubidi_writeReordered * * @param src A pointer to the RTL run text. * * @param srcLength The length of the RTL run. * * @param dest A pointer to where the reordered text is to be copied. * <code>src[srcLength]</code> and <code>dest[destSize]</code> * must not overlap. * * @param destSize The size of the <code>dest</code> buffer, * in number of UChars. * If the <code>UBIDI_REMOVE_BIDI_CONTROLS</code> option * is set, then the destination length may be less than * <code>srcLength</code>. * If this option is not set, then the destination length * will be exactly <code>srcLength</code>. * * @param options A bit set of options for the reordering that control * how the reordered text is written. * See the <code>options</code> parameter in <code>ubidi_writeReordered()</code>. * * @param pErrorCode must be a valid pointer to an error code value. * * @return The length of the output string. * @stable ICU 2.0 */ U_STABLE int32_t U_EXPORT2 ubidi_writeReverse(const UChar *src, int32_t srcLength, UChar *dest, int32_t destSize, uint16_t options, UErrorCode *pErrorCode); /*#define BIDI_SAMPLE_CODE*/ /*@}*/ #endif