The Tor Browser: intl/icu/source/common/caniter.cpp@fc2d59ddac77 (annotated)

intl/icu/source/common/caniter.cpp@fc2d59ddac77 (annotated)

intl/icu/source/common/caniter.cpp

Wed, 31 Dec 2014 07:22:50 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 07:22:50 +0100
branch: TOR_BUG_3246
changeset 4: fc2d59ddac77
permissions: -rw-r--r--

Correct previous dual key logic pending first delivery installment.

 /*
  *****************************************************************************
  * Copyright (C) 1996-2011, 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}
 : \u0041\u030A\u0064\u0307\u0327
  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
 : \u0041\u030A\u0064\u0327\u0307
  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
 : \u0041\u030A\u1E0B\u0327
  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
 : \u0041\u030A\u1E11\u0307
  = {LATIN CAPITAL LETTER A}{COMBINING RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
 : \u00C5\u0064\u0307\u0327
  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
 : \u00C5\u0064\u0327\u0307
  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
 : \u00C5\u1E0B\u0327
  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
 : \u00C5\u1E11\u0307
  = {LATIN CAPITAL LETTER A WITH RING ABOVE}{LATIN SMALL LETTER D WITH CEDILLA}{COMBINING DOT ABOVE}
 : \u212B\u0064\u0307\u0327
  = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING DOT ABOVE}{COMBINING CEDILLA}
 : \u212B\u0064\u0327\u0307
  = {ANGSTROM SIGN}{LATIN SMALL LETTER D}{COMBINING CEDILLA}{COMBINING DOT ABOVE}
 : \u212B\u1E0B\u0327
  = {ANGSTROM SIGN}{LATIN SMALL LETTER D WITH DOT ABOVE}{COMBINING CEDILLA}
 : \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(*Normalizer2Factory::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 = -1;
         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.replace(i, U16_LENGTH(cp), NULL, 0), skipZeros, &subpermute, status);
         /* Test for buffer overflows */
         if(U_FAILURE(status)) {
             return;
         }
         // The upper replace 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 = -1;
     //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 = -1;
         //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())) {
         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 = -1;
     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 = -1;
             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);
     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 */

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intl/icu/source/common/caniter.cpp@fc2d59ddac77 (annotated)

intl/icu/source/common/caniter.cpp