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authorRémi Verschelde <rverschelde@gmail.com>2020-11-28 09:03:15 +0100
committerGitHub <noreply@github.com>2020-11-28 09:03:15 +0100
commita6751e6c58e73d6b8d04e98bba5fb6e380fdf34f (patch)
treebf22de8b8d89dee6a3b59c22adacff8f62a8d5eb /thirdparty/icu4c/common/caniter.cpp
parentbd846001327dacd35a84b0759f8b7ca8b892e841 (diff)
parent7e2c0ffd1a19d5806a7fcf57e25d2465f7a8f8b6 (diff)
Merge pull request #41100 from bruvzg/ctl_text_server_interface
[Complex Text Layouts] Implement TextServer interface.
Diffstat (limited to 'thirdparty/icu4c/common/caniter.cpp')
-rw-r--r--thirdparty/icu4c/common/caniter.cpp586
1 files changed, 586 insertions, 0 deletions
diff --git a/thirdparty/icu4c/common/caniter.cpp b/thirdparty/icu4c/common/caniter.cpp
new file mode 100644
index 0000000000..b28acfc84e
--- /dev/null
+++ b/thirdparty/icu4c/common/caniter.cpp
@@ -0,0 +1,586 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+ *****************************************************************************
+ * Copyright (C) 1996-2015, International Business Machines Corporation and
+ * others. All Rights Reserved.
+ *****************************************************************************
+ */
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_NORMALIZATION
+
+#include "unicode/caniter.h"
+#include "unicode/normalizer2.h"
+#include "unicode/uchar.h"
+#include "unicode/uniset.h"
+#include "unicode/usetiter.h"
+#include "unicode/ustring.h"
+#include "unicode/utf16.h"
+#include "cmemory.h"
+#include "hash.h"
+#include "normalizer2impl.h"
+
+/**
+ * This class allows one to iterate through all the strings that are canonically equivalent to a given
+ * string. For example, here are some sample results:
+Results for: {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
+1: \u0041\u030A\u0064\u0307\u0327
+ = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
+2: \u0041\u030A\u0064\u0327\u0307
+ = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
+3: \u0041\u030A\u1E0B\u0327
+ = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
+4: \u0041\u030A\u1E11\u0307
+ = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
+5: \u00C5\u0064\u0307\u0327
+ = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
+6: \u00C5\u0064\u0327\u0307
+ = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
+7: \u00C5\u1E0B\u0327
+ = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
+8: \u00C5\u1E11\u0307
+ = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
+9: \u212B\u0064\u0307\u0327
+ = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
+10: \u212B\u0064\u0327\u0307
+ = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
+11: \u212B\u1E0B\u0327
+ = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
+12: \u212B\u1E11\u0307
+ = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
+ *<br>Note: the code is intended for use with small strings, and is not suitable for larger ones,
+ * since it has not been optimized for that situation.
+ *@author M. Davis
+ *@draft
+ */
+
+// public
+
+U_NAMESPACE_BEGIN
+
+// TODO: add boilerplate methods.
+
+UOBJECT_DEFINE_RTTI_IMPLEMENTATION(CanonicalIterator)
+
+/**
+ *@param source string to get results for
+ */
+CanonicalIterator::CanonicalIterator(const UnicodeString &sourceStr, UErrorCode &status) :
+ pieces(NULL),
+ pieces_length(0),
+ pieces_lengths(NULL),
+ current(NULL),
+ current_length(0),
+ nfd(*Normalizer2::getNFDInstance(status)),
+ nfcImpl(*Normalizer2Factory::getNFCImpl(status))
+{
+ if(U_SUCCESS(status) && nfcImpl.ensureCanonIterData(status)) {
+ setSource(sourceStr, status);
+ }
+}
+
+CanonicalIterator::~CanonicalIterator() {
+ cleanPieces();
+}
+
+void CanonicalIterator::cleanPieces() {
+ int32_t i = 0;
+ if(pieces != NULL) {
+ for(i = 0; i < pieces_length; i++) {
+ if(pieces[i] != NULL) {
+ delete[] pieces[i];
+ }
+ }
+ uprv_free(pieces);
+ pieces = NULL;
+ pieces_length = 0;
+ }
+ if(pieces_lengths != NULL) {
+ uprv_free(pieces_lengths);
+ pieces_lengths = NULL;
+ }
+ if(current != NULL) {
+ uprv_free(current);
+ current = NULL;
+ current_length = 0;
+ }
+}
+
+/**
+ *@return gets the source: NOTE: it is the NFD form of source
+ */
+UnicodeString CanonicalIterator::getSource() {
+ return source;
+}
+
+/**
+ * Resets the iterator so that one can start again from the beginning.
+ */
+void CanonicalIterator::reset() {
+ done = FALSE;
+ for (int i = 0; i < current_length; ++i) {
+ current[i] = 0;
+ }
+}
+
+/**
+ *@return the next string that is canonically equivalent. The value null is returned when
+ * the iteration is done.
+ */
+UnicodeString CanonicalIterator::next() {
+ int32_t i = 0;
+
+ if (done) {
+ buffer.setToBogus();
+ return buffer;
+ }
+
+ // delete old contents
+ buffer.remove();
+
+ // construct return value
+
+ for (i = 0; i < pieces_length; ++i) {
+ buffer.append(pieces[i][current[i]]);
+ }
+ //String result = buffer.toString(); // not needed
+
+ // find next value for next time
+
+ for (i = current_length - 1; ; --i) {
+ if (i < 0) {
+ done = TRUE;
+ break;
+ }
+ current[i]++;
+ if (current[i] < pieces_lengths[i]) break; // got sequence
+ current[i] = 0;
+ }
+ return buffer;
+}
+
+/**
+ *@param set the source string to iterate against. This allows the same iterator to be used
+ * while changing the source string, saving object creation.
+ */
+void CanonicalIterator::setSource(const UnicodeString &newSource, UErrorCode &status) {
+ int32_t list_length = 0;
+ UChar32 cp = 0;
+ int32_t start = 0;
+ int32_t i = 0;
+ UnicodeString *list = NULL;
+
+ nfd.normalize(newSource, source, status);
+ if(U_FAILURE(status)) {
+ return;
+ }
+ done = FALSE;
+
+ cleanPieces();
+
+ // catch degenerate case
+ if (newSource.length() == 0) {
+ pieces = (UnicodeString **)uprv_malloc(sizeof(UnicodeString *));
+ pieces_lengths = (int32_t*)uprv_malloc(1 * sizeof(int32_t));
+ pieces_length = 1;
+ current = (int32_t*)uprv_malloc(1 * sizeof(int32_t));
+ current_length = 1;
+ if (pieces == NULL || pieces_lengths == NULL || current == NULL) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ goto CleanPartialInitialization;
+ }
+ current[0] = 0;
+ pieces[0] = new UnicodeString[1];
+ pieces_lengths[0] = 1;
+ if (pieces[0] == 0) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ goto CleanPartialInitialization;
+ }
+ return;
+ }
+
+
+ list = new UnicodeString[source.length()];
+ if (list == 0) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ goto CleanPartialInitialization;
+ }
+
+ // i should initialy be the number of code units at the
+ // start of the string
+ i = U16_LENGTH(source.char32At(0));
+ //int32_t i = 1;
+ // find the segments
+ // This code iterates through the source string and
+ // extracts segments that end up on a codepoint that
+ // doesn't start any decompositions. (Analysis is done
+ // on the NFD form - see above).
+ for (; i < source.length(); i += U16_LENGTH(cp)) {
+ cp = source.char32At(i);
+ if (nfcImpl.isCanonSegmentStarter(cp)) {
+ source.extract(start, i-start, list[list_length++]); // add up to i
+ start = i;
+ }
+ }
+ source.extract(start, i-start, list[list_length++]); // add last one
+
+
+ // allocate the arrays, and find the strings that are CE to each segment
+ pieces = (UnicodeString **)uprv_malloc(list_length * sizeof(UnicodeString *));
+ pieces_length = list_length;
+ pieces_lengths = (int32_t*)uprv_malloc(list_length * sizeof(int32_t));
+ current = (int32_t*)uprv_malloc(list_length * sizeof(int32_t));
+ current_length = list_length;
+ if (pieces == NULL || pieces_lengths == NULL || current == NULL) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ goto CleanPartialInitialization;
+ }
+
+ for (i = 0; i < current_length; i++) {
+ current[i] = 0;
+ }
+ // for each segment, get all the combinations that can produce
+ // it after NFD normalization
+ for (i = 0; i < pieces_length; ++i) {
+ //if (PROGRESS) printf("SEGMENT\n");
+ pieces[i] = getEquivalents(list[i], pieces_lengths[i], status);
+ }
+
+ delete[] list;
+ return;
+// Common section to cleanup all local variables and reset object variables.
+CleanPartialInitialization:
+ if (list != NULL) {
+ delete[] list;
+ }
+ cleanPieces();
+}
+
+/**
+ * Dumb recursive implementation of permutation.
+ * TODO: optimize
+ * @param source the string to find permutations for
+ * @return the results in a set.
+ */
+void U_EXPORT2 CanonicalIterator::permute(UnicodeString &source, UBool skipZeros, Hashtable *result, UErrorCode &status) {
+ if(U_FAILURE(status)) {
+ return;
+ }
+ //if (PROGRESS) printf("Permute: %s\n", UToS(Tr(source)));
+ int32_t i = 0;
+
+ // optimization:
+ // if zero or one character, just return a set with it
+ // we check for length < 2 to keep from counting code points all the time
+ if (source.length() <= 2 && source.countChar32() <= 1) {
+ UnicodeString *toPut = new UnicodeString(source);
+ /* test for NULL */
+ if (toPut == 0) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ return;
+ }
+ result->put(source, toPut, status);
+ return;
+ }
+
+ // otherwise iterate through the string, and recursively permute all the other characters
+ UChar32 cp;
+ Hashtable subpermute(status);
+ if(U_FAILURE(status)) {
+ return;
+ }
+ subpermute.setValueDeleter(uprv_deleteUObject);
+
+ for (i = 0; i < source.length(); i += U16_LENGTH(cp)) {
+ cp = source.char32At(i);
+ const UHashElement *ne = NULL;
+ int32_t el = UHASH_FIRST;
+ UnicodeString subPermuteString = source;
+
+ // optimization:
+ // if the character is canonical combining class zero,
+ // don't permute it
+ if (skipZeros && i != 0 && u_getCombiningClass(cp) == 0) {
+ //System.out.println("Skipping " + Utility.hex(UTF16.valueOf(source, i)));
+ continue;
+ }
+
+ subpermute.removeAll();
+
+ // see what the permutations of the characters before and after this one are
+ //Hashtable *subpermute = permute(source.substring(0,i) + source.substring(i + UTF16.getCharCount(cp)));
+ permute(subPermuteString.remove(i, U16_LENGTH(cp)), skipZeros, &subpermute, status);
+ /* Test for buffer overflows */
+ if(U_FAILURE(status)) {
+ return;
+ }
+ // The upper remove is destructive. The question is do we have to make a copy, or we don't care about the contents
+ // of source at this point.
+
+ // prefix this character to all of them
+ ne = subpermute.nextElement(el);
+ while (ne != NULL) {
+ UnicodeString *permRes = (UnicodeString *)(ne->value.pointer);
+ UnicodeString *chStr = new UnicodeString(cp);
+ //test for NULL
+ if (chStr == NULL) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ return;
+ }
+ chStr->append(*permRes); //*((UnicodeString *)(ne->value.pointer));
+ //if (PROGRESS) printf(" Piece: %s\n", UToS(*chStr));
+ result->put(*chStr, chStr, status);
+ ne = subpermute.nextElement(el);
+ }
+ }
+ //return result;
+}
+
+// privates
+
+// we have a segment, in NFD. Find all the strings that are canonically equivalent to it.
+UnicodeString* CanonicalIterator::getEquivalents(const UnicodeString &segment, int32_t &result_len, UErrorCode &status) {
+ Hashtable result(status);
+ Hashtable permutations(status);
+ Hashtable basic(status);
+ if (U_FAILURE(status)) {
+ return 0;
+ }
+ result.setValueDeleter(uprv_deleteUObject);
+ permutations.setValueDeleter(uprv_deleteUObject);
+ basic.setValueDeleter(uprv_deleteUObject);
+
+ UChar USeg[256];
+ int32_t segLen = segment.extract(USeg, 256, status);
+ getEquivalents2(&basic, USeg, segLen, status);
+
+ // now get all the permutations
+ // add only the ones that are canonically equivalent
+ // TODO: optimize by not permuting any class zero.
+
+ const UHashElement *ne = NULL;
+ int32_t el = UHASH_FIRST;
+ //Iterator it = basic.iterator();
+ ne = basic.nextElement(el);
+ //while (it.hasNext())
+ while (ne != NULL) {
+ //String item = (String) it.next();
+ UnicodeString item = *((UnicodeString *)(ne->value.pointer));
+
+ permutations.removeAll();
+ permute(item, CANITER_SKIP_ZEROES, &permutations, status);
+ const UHashElement *ne2 = NULL;
+ int32_t el2 = UHASH_FIRST;
+ //Iterator it2 = permutations.iterator();
+ ne2 = permutations.nextElement(el2);
+ //while (it2.hasNext())
+ while (ne2 != NULL) {
+ //String possible = (String) it2.next();
+ //UnicodeString *possible = new UnicodeString(*((UnicodeString *)(ne2->value.pointer)));
+ UnicodeString possible(*((UnicodeString *)(ne2->value.pointer)));
+ UnicodeString attempt;
+ nfd.normalize(possible, attempt, status);
+
+ // TODO: check if operator == is semanticaly the same as attempt.equals(segment)
+ if (attempt==segment) {
+ //if (PROGRESS) printf("Adding Permutation: %s\n", UToS(Tr(*possible)));
+ // TODO: use the hashtable just to catch duplicates - store strings directly (somehow).
+ result.put(possible, new UnicodeString(possible), status); //add(possible);
+ } else {
+ //if (PROGRESS) printf("-Skipping Permutation: %s\n", UToS(Tr(*possible)));
+ }
+
+ ne2 = permutations.nextElement(el2);
+ }
+ ne = basic.nextElement(el);
+ }
+
+ /* Test for buffer overflows */
+ if(U_FAILURE(status)) {
+ return 0;
+ }
+ // convert into a String[] to clean up storage
+ //String[] finalResult = new String[result.size()];
+ UnicodeString *finalResult = NULL;
+ int32_t resultCount;
+ if((resultCount = result.count()) != 0) {
+ finalResult = new UnicodeString[resultCount];
+ if (finalResult == 0) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ return NULL;
+ }
+ }
+ else {
+ status = U_ILLEGAL_ARGUMENT_ERROR;
+ return NULL;
+ }
+ //result.toArray(finalResult);
+ result_len = 0;
+ el = UHASH_FIRST;
+ ne = result.nextElement(el);
+ while(ne != NULL) {
+ finalResult[result_len++] = *((UnicodeString *)(ne->value.pointer));
+ ne = result.nextElement(el);
+ }
+
+
+ return finalResult;
+}
+
+Hashtable *CanonicalIterator::getEquivalents2(Hashtable *fillinResult, const UChar *segment, int32_t segLen, UErrorCode &status) {
+
+ if (U_FAILURE(status)) {
+ return NULL;
+ }
+
+ //if (PROGRESS) printf("Adding: %s\n", UToS(Tr(segment)));
+
+ UnicodeString toPut(segment, segLen);
+
+ fillinResult->put(toPut, new UnicodeString(toPut), status);
+
+ UnicodeSet starts;
+
+ // cycle through all the characters
+ UChar32 cp;
+ for (int32_t i = 0; i < segLen; i += U16_LENGTH(cp)) {
+ // see if any character is at the start of some decomposition
+ U16_GET(segment, 0, i, segLen, cp);
+ if (!nfcImpl.getCanonStartSet(cp, starts)) {
+ continue;
+ }
+ // if so, see which decompositions match
+ UnicodeSetIterator iter(starts);
+ while (iter.next()) {
+ UChar32 cp2 = iter.getCodepoint();
+ Hashtable remainder(status);
+ remainder.setValueDeleter(uprv_deleteUObject);
+ if (extract(&remainder, cp2, segment, segLen, i, status) == NULL) {
+ continue;
+ }
+
+ // there were some matches, so add all the possibilities to the set.
+ UnicodeString prefix(segment, i);
+ prefix += cp2;
+
+ int32_t el = UHASH_FIRST;
+ const UHashElement *ne = remainder.nextElement(el);
+ while (ne != NULL) {
+ UnicodeString item = *((UnicodeString *)(ne->value.pointer));
+ UnicodeString *toAdd = new UnicodeString(prefix);
+ /* test for NULL */
+ if (toAdd == 0) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ return NULL;
+ }
+ *toAdd += item;
+ fillinResult->put(*toAdd, toAdd, status);
+
+ //if (PROGRESS) printf("Adding: %s\n", UToS(Tr(*toAdd)));
+
+ ne = remainder.nextElement(el);
+ }
+ }
+ }
+
+ /* Test for buffer overflows */
+ if(U_FAILURE(status)) {
+ return NULL;
+ }
+ return fillinResult;
+}
+
+/**
+ * See if the decomposition of cp2 is at segment starting at segmentPos
+ * (with canonical rearrangment!)
+ * If so, take the remainder, and return the equivalents
+ */
+Hashtable *CanonicalIterator::extract(Hashtable *fillinResult, UChar32 comp, const UChar *segment, int32_t segLen, int32_t segmentPos, UErrorCode &status) {
+//Hashtable *CanonicalIterator::extract(UChar32 comp, const UnicodeString &segment, int32_t segLen, int32_t segmentPos, UErrorCode &status) {
+ //if (PROGRESS) printf(" extract: %s, ", UToS(Tr(UnicodeString(comp))));
+ //if (PROGRESS) printf("%s, %i\n", UToS(Tr(segment)), segmentPos);
+
+ if (U_FAILURE(status)) {
+ return NULL;
+ }
+
+ UnicodeString temp(comp);
+ int32_t inputLen=temp.length();
+ UnicodeString decompString;
+ nfd.normalize(temp, decompString, status);
+ if (U_FAILURE(status)) {
+ return NULL;
+ }
+ if (decompString.isBogus()) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ return NULL;
+ }
+ const UChar *decomp=decompString.getBuffer();
+ int32_t decompLen=decompString.length();
+
+ // See if it matches the start of segment (at segmentPos)
+ UBool ok = FALSE;
+ UChar32 cp;
+ int32_t decompPos = 0;
+ UChar32 decompCp;
+ U16_NEXT(decomp, decompPos, decompLen, decompCp);
+
+ int32_t i = segmentPos;
+ while(i < segLen) {
+ U16_NEXT(segment, i, segLen, cp);
+
+ if (cp == decompCp) { // if equal, eat another cp from decomp
+
+ //if (PROGRESS) printf(" matches: %s\n", UToS(Tr(UnicodeString(cp))));
+
+ if (decompPos == decompLen) { // done, have all decomp characters!
+ temp.append(segment+i, segLen-i);
+ ok = TRUE;
+ break;
+ }
+ U16_NEXT(decomp, decompPos, decompLen, decompCp);
+ } else {
+ //if (PROGRESS) printf(" buffer: %s\n", UToS(Tr(UnicodeString(cp))));
+
+ // brute force approach
+ temp.append(cp);
+
+ /* TODO: optimize
+ // since we know that the classes are monotonically increasing, after zero
+ // e.g. 0 5 7 9 0 3
+ // we can do an optimization
+ // there are only a few cases that work: zero, less, same, greater
+ // if both classes are the same, we fail
+ // if the decomp class < the segment class, we fail
+
+ segClass = getClass(cp);
+ if (decompClass <= segClass) return null;
+ */
+ }
+ }
+ if (!ok)
+ return NULL; // we failed, characters left over
+
+ //if (PROGRESS) printf("Matches\n");
+
+ if (inputLen == temp.length()) {
+ fillinResult->put(UnicodeString(), new UnicodeString(), status);
+ return fillinResult; // succeed, but no remainder
+ }
+
+ // brute force approach
+ // check to make sure result is canonically equivalent
+ UnicodeString trial;
+ nfd.normalize(temp, trial, status);
+ if(U_FAILURE(status) || trial.compare(segment+segmentPos, segLen - segmentPos) != 0) {
+ return NULL;
+ }
+
+ return getEquivalents2(fillinResult, temp.getBuffer()+inputLen, temp.length()-inputLen, status);
+}
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_NORMALIZATION */