--- /dev/null
+/*
+******************************************************************************
+*
+* © 2016 and later: Unicode, Inc. and others.
+* License & terms of use: http://www.unicode.org/copyright.html
+*
+******************************************************************************
+* file name: ubiditransform.c
+* encoding: UTF-8
+* tab size: 8 (not used)
+* indentation:4
+*
+* created on: 2016jul24
+* created by: Lina Kemmel
+*
+*/
+
+#include "cmemory.h"
+#include "unicode/ubidi.h"
+#include "unicode/ustring.h"
+#include "unicode/ushape.h"
+#include "unicode/utf16.h"
+#include "ustr_imp.h"
+#include "unicode/ubiditransform.h"
+
+/* Some convenience defines */
+#define LTR UBIDI_LTR
+#define RTL UBIDI_RTL
+#define LOGICAL UBIDI_LOGICAL
+#define VISUAL UBIDI_VISUAL
+#define SHAPE_LOGICAL U_SHAPE_TEXT_DIRECTION_LOGICAL
+#define SHAPE_VISUAL U_SHAPE_TEXT_DIRECTION_VISUAL_LTR
+
+#define CHECK_LEN(STR, LEN, ERROR) { \
+ if (LEN == 0) return 0; \
+ if (LEN < -1) { *(ERROR) = U_ILLEGAL_ARGUMENT_ERROR; return 0; } \
+ if (LEN == -1) LEN = u_strlen(STR); \
+ }
+
+#define MAX_ACTIONS 7
+
+/**
+ * Typedef for a pointer to a function, which performs some operation (such as
+ * reordering, setting "inverse" mode, character mirroring, etc.). Return value
+ * indicates whether the text was changed in the course of this operation or
+ * not.
+ */
+typedef UBool (*UBiDiAction)(UBiDiTransform *, UErrorCode *);
+
+/**
+ * Structure that holds a predefined reordering scheme, including the following
+ * information:
+ * <ul>
+ * <li>an input base direction,</li>
+ * <li>an input order,</li>
+ * <li>an output base direction,</li>
+ * <li>an output order,</li>
+ * <li>a digit shaping direction,</li>
+ * <li>a letter shaping direction,</li>
+ * <li>a base direction that should be applied when the reordering engine is
+ * invoked (which can not always be derived from the caller-defined
+ * options),</li>
+ * <li>an array of pointers to functions that accomplish the bidi layout
+ * transformation.</li>
+ * </ul>
+ */
+typedef struct {
+ UBiDiLevel inLevel; /* input level */
+ UBiDiOrder inOrder; /* input order */
+ UBiDiLevel outLevel; /* output level */
+ UBiDiOrder outOrder; /* output order */
+ uint32_t digitsDir; /* digit shaping direction */
+ uint32_t lettersDir; /* letter shaping direction */
+ UBiDiLevel baseLevel; /* paragraph level to be used with setPara */
+ const UBiDiAction actions[MAX_ACTIONS]; /* array of pointers to functions carrying out the transformation */
+} ReorderingScheme;
+
+struct UBiDiTransform {
+ UBiDi *pBidi; /* pointer to a UBiDi object */
+ const ReorderingScheme *pActiveScheme; /* effective reordering scheme */
+ UChar *src; /* input text */
+ UChar *dest; /* output text */
+ uint32_t srcLength; /* input text length - not really needed as we are zero-terminated and can u_strlen */
+ uint32_t srcSize; /* input text capacity excluding the trailing zero */
+ uint32_t destSize; /* output text capacity */
+ uint32_t *pDestLength; /* number of UChars written to dest */
+ uint32_t reorderingOptions; /* reordering options - currently only suppot DO_MIRRORING */
+ uint32_t digits; /* digit option for ArabicShaping */
+ uint32_t letters; /* letter option for ArabicShaping */
+};
+
+U_DRAFT UBiDiTransform* U_EXPORT2
+ubiditransform_open(UErrorCode *pErrorCode)
+{
+ UBiDiTransform *pBiDiTransform = NULL;
+ if (U_SUCCESS(*pErrorCode)) {
+ pBiDiTransform = (UBiDiTransform*) uprv_calloc(1, sizeof(UBiDiTransform));
+ if (pBiDiTransform == NULL) {
+ *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
+ }
+ }
+ return pBiDiTransform;
+}
+
+U_DRAFT void U_EXPORT2
+ubiditransform_close(UBiDiTransform *pBiDiTransform)
+{
+ if (pBiDiTransform != NULL) {
+ if (pBiDiTransform->pBidi != NULL) {
+ ubidi_close(pBiDiTransform->pBidi);
+ }
+ if (pBiDiTransform->src != NULL) {
+ uprv_free(pBiDiTransform->src);
+ }
+ uprv_free(pBiDiTransform);
+ }
+}
+
+/**
+ * Performs Bidi resolution of text.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_resolve(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ ubidi_setPara(pTransform->pBidi, pTransform->src, pTransform->srcLength,
+ pTransform->pActiveScheme->baseLevel, NULL, pErrorCode);
+ return FALSE;
+}
+
+/**
+ * Performs basic reordering of text (Logical -> Visual LTR).
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_reorder(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ ubidi_writeReordered(pTransform->pBidi, pTransform->dest, pTransform->destSize,
+ pTransform->reorderingOptions, pErrorCode);
+
+ *pTransform->pDestLength = pTransform->srcLength;
+ pTransform->reorderingOptions = UBIDI_REORDER_DEFAULT;
+ return TRUE;
+}
+
+/**
+ * Sets "inverse" mode on the <code>UBiDi</code> object.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_setInverse(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ (void)pErrorCode;
+ ubidi_setInverse(pTransform->pBidi, TRUE);
+ ubidi_setReorderingMode(pTransform->pBidi, UBIDI_REORDER_INVERSE_LIKE_DIRECT);
+ return FALSE;
+}
+
+/**
+ * Sets "runs only" reordering mode indicating a Logical LTR <-> Logical RTL
+ * transformation.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_setRunsOnly(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ (void)pErrorCode;
+ ubidi_setReorderingMode(pTransform->pBidi, UBIDI_REORDER_RUNS_ONLY);
+ return FALSE;
+}
+
+/**
+ * Performs string reverse.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_reverse(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ ubidi_writeReverse(pTransform->src, pTransform->srcLength,
+ pTransform->dest, pTransform->destSize,
+ UBIDI_REORDER_DEFAULT, pErrorCode);
+ *pTransform->pDestLength = pTransform->srcLength;
+ return TRUE;
+}
+
+/**
+ * Applies a new value to the text that serves as input at the current
+ * processing step. This value is identical to the original one when we begin
+ * the processing, but usually changes as the transformation progresses.
+ *
+ * @param pTransform A pointer to the <code>UBiDiTransform</code> structure.
+ * @param newSrc A pointer whose value is to be used as input text.
+ * @param newLength A length of the new text in <code>UChar</code>s.
+ * @param newSize A new source capacity in <code>UChar</code>s.
+ * @param pErrorCode Pointer to the error code value.
+ */
+static void
+updateSrc(UBiDiTransform *pTransform, const UChar *newSrc, uint32_t newLength,
+ uint32_t newSize, UErrorCode *pErrorCode)
+{
+ if (newSize < newLength) {
+ *pErrorCode = U_BUFFER_OVERFLOW_ERROR;
+ return;
+ }
+ if (newSize > pTransform->srcSize) {
+ newSize += 50; // allocate slightly more than needed right now
+ if (pTransform->src != NULL) {
+ uprv_free(pTransform->src);
+ pTransform->src = NULL;
+ }
+ pTransform->src = (UChar *)uprv_malloc(newSize * sizeof(UChar));
+ if (pTransform->src == NULL) {
+ *pErrorCode = U_MEMORY_ALLOCATION_ERROR;
+ //pTransform->srcLength = pTransform->srcSize = 0;
+ return;
+ }
+ pTransform->srcSize = newSize;
+ }
+ u_strncpy(pTransform->src, newSrc, newLength);
+ pTransform->srcLength = u_terminateUChars(pTransform->src,
+ pTransform->srcSize, newLength, pErrorCode);
+}
+
+/**
+ * Calls a lower level shaping function.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param options Shaping options.
+ * @param pErrorCode Pointer to the error code value.
+ */
+static void
+doShape(UBiDiTransform *pTransform, uint32_t options, UErrorCode *pErrorCode)
+{
+ *pTransform->pDestLength = u_shapeArabic(pTransform->src,
+ pTransform->srcLength, pTransform->dest, pTransform->destSize,
+ options, pErrorCode);
+}
+
+/**
+ * Performs digit and letter shaping.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_shapeArabic(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ if ((pTransform->letters | pTransform->digits) == 0) {
+ return FALSE;
+ }
+ if (pTransform->pActiveScheme->lettersDir == pTransform->pActiveScheme->digitsDir) {
+ doShape(pTransform, pTransform->letters | pTransform->digits | pTransform->pActiveScheme->lettersDir,
+ pErrorCode);
+ } else {
+ doShape(pTransform, pTransform->digits | pTransform->pActiveScheme->digitsDir, pErrorCode);
+ if (U_SUCCESS(*pErrorCode)) {
+ updateSrc(pTransform, pTransform->dest, *pTransform->pDestLength,
+ *pTransform->pDestLength, pErrorCode);
+ doShape(pTransform, pTransform->letters | pTransform->pActiveScheme->lettersDir,
+ pErrorCode);
+ }
+ }
+ return TRUE;
+}
+
+/**
+ * Performs character mirroring.
+ *
+ * @param pTransform Pointer to the <code>UBiDiTransform</code> structure.
+ * @param pErrorCode Pointer to the error code value.
+ *
+ * @return Whether or not this function modifies the text. Besides the return
+ * value, the caller should also check <code>U_SUCCESS(*pErrorCode)</code>.
+ */
+static UBool
+action_mirror(UBiDiTransform *pTransform, UErrorCode *pErrorCode)
+{
+ UChar32 c;
+ uint32_t i = 0, j = 0;
+ if (0 == (pTransform->reorderingOptions & UBIDI_DO_MIRRORING)) {
+ return FALSE;
+ }
+ if (pTransform->destSize < pTransform->srcLength) {
+ *pErrorCode = U_BUFFER_OVERFLOW_ERROR;
+ return FALSE;
+ }
+ do {
+ UBool isOdd = ubidi_getLevelAt(pTransform->pBidi, i) & 1;
+ U16_NEXT(pTransform->src, i, pTransform->srcLength, c);
+ U16_APPEND_UNSAFE(pTransform->dest, j, isOdd ? u_charMirror(c) : c);
+ } while (i < pTransform->srcLength);
+
+ *pTransform->pDestLength = pTransform->srcLength;
+ pTransform->reorderingOptions = UBIDI_REORDER_DEFAULT;
+ return TRUE;
+}
+
+/**
+ * All possible reordering schemes.
+ *
+ */
+static const ReorderingScheme Schemes[] =
+{
+ /* 0: Logical LTR => Visual LTR */
+ {LTR, LOGICAL, LTR, VISUAL, SHAPE_LOGICAL, SHAPE_LOGICAL, LTR,
+ {action_shapeArabic, action_resolve, action_reorder, NULL}},
+ /* 1: Logical RTL => Visual LTR */
+ {RTL, LOGICAL, LTR, VISUAL, SHAPE_LOGICAL, SHAPE_VISUAL, RTL,
+ {action_resolve, action_reorder, action_shapeArabic, NULL}},
+ /* 2: Logical LTR => Visual RTL */
+ {LTR, LOGICAL, RTL, VISUAL, SHAPE_LOGICAL, SHAPE_LOGICAL, LTR,
+ {action_shapeArabic, action_resolve, action_reorder, action_reverse, NULL}},
+ /* 3: Logical RTL => Visual RTL */
+ {RTL, LOGICAL, RTL, VISUAL, SHAPE_LOGICAL, SHAPE_VISUAL, RTL,
+ {action_resolve, action_reorder, action_shapeArabic, action_reverse, NULL}},
+ /* 4: Visual LTR => Logical RTL */
+ {LTR, VISUAL, RTL, LOGICAL, SHAPE_LOGICAL, SHAPE_VISUAL, RTL,
+ {action_shapeArabic, action_setInverse, action_resolve, action_reorder, NULL}},
+ /* 5: Visual RTL => Logical RTL */
+ {RTL, VISUAL, RTL, LOGICAL, SHAPE_LOGICAL, SHAPE_VISUAL, RTL,
+ {action_reverse, action_shapeArabic, action_setInverse, action_resolve, action_reorder, NULL}},
+ /* 6: Visual LTR => Logical LTR */
+ {LTR, VISUAL, LTR, LOGICAL, SHAPE_LOGICAL, SHAPE_LOGICAL, LTR,
+ {action_setInverse, action_resolve, action_reorder, action_shapeArabic, NULL}},
+ /* 7: Visual RTL => Logical LTR */
+ {RTL, VISUAL, LTR, LOGICAL, SHAPE_LOGICAL, SHAPE_LOGICAL, LTR,
+ {action_reverse, action_setInverse, action_resolve, action_reorder, action_shapeArabic, NULL}},
+ /* 8: Logical LTR => Logical RTL */
+ {LTR, LOGICAL, RTL, LOGICAL, SHAPE_LOGICAL, SHAPE_LOGICAL, LTR,
+ {action_shapeArabic, action_resolve, action_mirror, action_setRunsOnly, action_resolve, action_reorder, NULL}},
+ /* 9: Logical RTL => Logical LTR */
+ {RTL, LOGICAL, LTR, LOGICAL, SHAPE_LOGICAL, SHAPE_LOGICAL, RTL,
+ {action_resolve, action_mirror, action_setRunsOnly, action_resolve, action_reorder, action_shapeArabic, NULL}},
+ /* 10: Visual LTR => Visual RTL */
+ {LTR, VISUAL, RTL, VISUAL, SHAPE_LOGICAL, SHAPE_VISUAL, LTR,
+ {action_shapeArabic, action_setInverse, action_resolve, action_mirror, action_reverse, NULL}},
+ /* 11: Visual RTL => Visual LTR */
+ {RTL, VISUAL, LTR, VISUAL, SHAPE_LOGICAL, SHAPE_VISUAL, LTR,
+ {action_reverse, action_shapeArabic, action_setInverse, action_resolve, action_mirror, NULL}},
+ /* 12: Logical LTR => Logical LTR */
+ {LTR, LOGICAL, LTR, LOGICAL, SHAPE_LOGICAL, SHAPE_LOGICAL, LTR,
+ {action_resolve, action_mirror, action_shapeArabic, NULL}},
+ /* 13: Logical RTL => Logical RTL */
+ {RTL, LOGICAL, RTL, LOGICAL, SHAPE_VISUAL, SHAPE_LOGICAL, RTL,
+ {action_resolve, action_mirror, action_shapeArabic, NULL}},
+ /* 14: Visual LTR => Visual LTR */
+ {LTR, VISUAL, LTR, VISUAL, SHAPE_LOGICAL, SHAPE_VISUAL, LTR,
+ {action_resolve, action_mirror, action_shapeArabic, NULL}},
+ /* 15: Visual RTL => Visual RTL */
+ {RTL, VISUAL, RTL, VISUAL, SHAPE_LOGICAL, SHAPE_VISUAL, LTR,
+ {action_reverse, action_resolve, action_mirror, action_shapeArabic, action_reverse, NULL}}
+};
+
+static const uint32_t nSchemes = sizeof(Schemes) / sizeof(*Schemes);
+
+/**
+ * When the direction option is <code>UBIDI_DEFAULT_LTR</code> or
+ * <code>UBIDI_DEFAULT_RTL</code>, resolve the base direction according to that
+ * of the first strong bidi character.
+ */
+static void
+resolveBaseDirection(const UChar *text, uint32_t length,
+ UBiDiLevel *pInLevel, UBiDiLevel *pOutLevel)
+{
+ switch (*pInLevel) {
+ case UBIDI_DEFAULT_LTR:
+ case UBIDI_DEFAULT_RTL: {
+ UBiDiLevel level = ubidi_getBaseDirection(text, length);
+ *pInLevel = level != UBIDI_NEUTRAL ? level
+ : *pInLevel == UBIDI_DEFAULT_RTL ? RTL : LTR;
+ break;
+ }
+ default:
+ *pInLevel &= 1;
+ break;
+ }
+ switch (*pOutLevel) {
+ case UBIDI_DEFAULT_LTR:
+ case UBIDI_DEFAULT_RTL:
+ *pOutLevel = *pInLevel;
+ break;
+ default:
+ *pOutLevel &= 1;
+ break;
+ }
+}
+
+/**
+ * Finds a valid <code>ReorderingScheme</code> matching the
+ * caller-defined scheme.
+ *
+ * @return A valid <code>ReorderingScheme</code> object or NULL
+ */
+static const ReorderingScheme*
+findMatchingScheme(UBiDiLevel inLevel, UBiDiLevel outLevel,
+ UBiDiOrder inOrder, UBiDiOrder outOrder)
+{
+ uint32_t i;
+ for (i = 0; i < nSchemes; i++) {
+ const ReorderingScheme *pScheme = Schemes + i;
+ if (inLevel == pScheme->inLevel && outLevel == pScheme->outLevel
+ && inOrder == pScheme->inOrder && outOrder == pScheme->outOrder) {
+ return pScheme;
+ }
+ }
+ return NULL;
+}
+
+U_DRAFT uint32_t U_EXPORT2
+ubiditransform_transform(UBiDiTransform *pBiDiTransform,
+ const UChar *src, int32_t srcLength,
+ UChar *dest, int32_t destSize,
+ UBiDiLevel inParaLevel, UBiDiOrder inOrder,
+ UBiDiLevel outParaLevel, UBiDiOrder outOrder,
+ UBiDiMirroring doMirroring, uint32_t shapingOptions,
+ UErrorCode *pErrorCode)
+{
+ uint32_t destLength = 0;
+ UBool textChanged = FALSE;
+ const UBiDiTransform *pOrigTransform = pBiDiTransform;
+ const UBiDiAction *action = NULL;
+
+ if (U_FAILURE(*pErrorCode)) {
+ return 0;
+ }
+ if (src == NULL || dest == NULL) {
+ *pErrorCode = U_ILLEGAL_ARGUMENT_ERROR;
+ return 0;
+ }
+ CHECK_LEN(src, srcLength, pErrorCode);
+ CHECK_LEN(dest, destSize, pErrorCode);
+
+ if (pBiDiTransform == NULL) {
+ pBiDiTransform = ubiditransform_open(pErrorCode);
+ if (U_FAILURE(*pErrorCode)) {
+ return 0;
+ }
+ }
+ /* Current limitation: in multiple paragraphs will be resolved according
+ to the 1st paragraph */
+ resolveBaseDirection(src, srcLength, &inParaLevel, &outParaLevel);
+
+ pBiDiTransform->pActiveScheme = findMatchingScheme(inParaLevel, outParaLevel,
+ inOrder, outOrder);
+ if (pBiDiTransform->pActiveScheme == NULL) {
+ goto cleanup;
+ }
+ pBiDiTransform->reorderingOptions = doMirroring ? UBIDI_DO_MIRRORING
+ : UBIDI_REORDER_DEFAULT;
+
+ /* Ignore TEXT_DIRECTION_* flags, as we apply our own depending on the text
+ scheme at the time shaping is invoked. */
+ shapingOptions &= ~U_SHAPE_TEXT_DIRECTION_MASK;
+ pBiDiTransform->digits = shapingOptions & ~U_SHAPE_LETTERS_MASK;
+ pBiDiTransform->letters = shapingOptions & ~U_SHAPE_DIGITS_MASK;
+
+ updateSrc(pBiDiTransform, src, srcLength, destSize > srcLength ? destSize : srcLength, pErrorCode);
+ if (U_FAILURE(*pErrorCode)) {
+ goto cleanup;
+ }
+ if (pBiDiTransform->pBidi == NULL) {
+ pBiDiTransform->pBidi = ubidi_openSized(0, 0, pErrorCode);
+ if (U_FAILURE(*pErrorCode)) {
+ goto cleanup;
+ }
+ }
+ pBiDiTransform->dest = dest;
+ pBiDiTransform->destSize = destSize;
+ pBiDiTransform->pDestLength = &destLength;
+
+ /* Checking for U_SUCCESS() within the loop to bail out on first failure. */
+ for (action = pBiDiTransform->pActiveScheme->actions; *action && U_SUCCESS(*pErrorCode); action++) {
+ if ((*action)(pBiDiTransform, pErrorCode)) {
+ if (action + 1) {
+ updateSrc(pBiDiTransform, pBiDiTransform->dest, *pBiDiTransform->pDestLength,
+ *pBiDiTransform->pDestLength, pErrorCode);
+ }
+ textChanged = TRUE;
+ }
+ }
+ ubidi_setInverse(pBiDiTransform->pBidi, FALSE);
+
+ if (!textChanged && U_SUCCESS(*pErrorCode)) {
+ /* Text was not changed - just copy src to dest */
+ if (destSize < srcLength) {
+ *pErrorCode = U_BUFFER_OVERFLOW_ERROR;
+ } else {
+ u_strncpy(dest, src, srcLength);
+ destLength = srcLength;
+ }
+ }
+cleanup:
+ if (pOrigTransform != pBiDiTransform) {
+ ubiditransform_close(pBiDiTransform);
+ } else {
+ pBiDiTransform->dest = NULL;
+ pBiDiTransform->pDestLength = NULL;
+ pBiDiTransform->srcLength = 0;
+ pBiDiTransform->destSize = 0;
+ }
+ return U_FAILURE(*pErrorCode) ? 0 : destLength;
+}
projects / apple / icu.git / blobdiff