Update ICU to 75.1

904da4ae1c86fc5542eac7f1cd18d97b72eb8517

1 files changed, 242 insertions, 131 deletions

diff --git a/contrib/libs/icu/common/uresbund.cpp b/contrib/libs/icu/common/uresbund.cpp
index d02bba8921..ea4327b314 100644
--- a/contrib/libs/icu/common/uresbund.cpp
+++ b/contrib/libs/icu/common/uresbund.cpp
@@ -24,6 +24,7 @@
 #include "unicode/ures.h"
 #include "unicode/ustring.h"
 #include "unicode/ucnv.h"
+#include "bytesinkutil.h"
 #include "charstr.h"
 #include "uresimp.h"
 #include "ustr_imp.h"
@@ -93,8 +94,16 @@ static UBool chopLocale(char *name) {
 
 static UBool hasVariant(const char* localeID) {
     UErrorCode err = U_ZERO_ERROR;
-    int32_t variantLength = uloc_getVariant(localeID, nullptr, 0, &err);
-    return variantLength != 0;
+    CheckedArrayByteSink sink(nullptr, 0);
+    ulocimp_getSubtags(
+            localeID,
+            nullptr,
+            nullptr,
+            nullptr,
+            &sink,
+            nullptr,
+            err);
+    return sink.NumberOfBytesAppended() != 0;
 }
 
 // This file contains the tables for doing locale fallback, which are generated
@@ -208,17 +217,11 @@ static bool getParentLocaleID(char *name, const char *origName, UResOpenType ope
     }
     
     UErrorCode err = U_ZERO_ERROR;
-    const char* tempNamePtr = name;
-    CharString language = ulocimp_getLanguage(tempNamePtr, &tempNamePtr, err);
-    if (*tempNamePtr == '_') {
-        ++tempNamePtr;
-    }
-    CharString script = ulocimp_getScript(tempNamePtr, &tempNamePtr, err);
-    if (*tempNamePtr == '_') {
-        ++tempNamePtr;
-    }
-    CharString region = ulocimp_getCountry(tempNamePtr, &tempNamePtr, err);
-    CharString workingLocale;
+    CharString language;
+    CharString script;
+    CharString region;
+    ulocimp_getSubtags(name, &language, &script, &region, nullptr, nullptr, err);
+
     if (U_FAILURE(err)) {
         // hopefully this never happens...
         return chopLocale(name);
@@ -237,13 +240,15 @@ static bool getParentLocaleID(char *name, const char *origName, UResOpenType ope
         }
     }
 
+    CharString workingLocale;
+
     // if it's not in the parent locale table, figure out the fallback script algorithmically
     // (see CLDR-15265 for an explanation of the algorithm)
     if (!script.isEmpty() && !region.isEmpty()) {
         // if "name" has both script and region, is the script the default script?
         // - if so, remove it and keep the region
         // - if not, remove the region and keep the script
-        if (getDefaultScript(language, region) == script.toStringPiece()) {
+        if (getDefaultScript(language, region) == script) {
             workingLocale.append(language, err).append("_", err).append(region, err);
         } else {
             workingLocale.append(language, err).append("_", err).append(script, err);
@@ -253,12 +258,9 @@ static bool getParentLocaleID(char *name, const char *origName, UResOpenType ope
         // - if yes, replace the region with the script from the original locale ID
         // - if no, replace the region with the default script for that language and region
         UErrorCode err = U_ZERO_ERROR;
-        tempNamePtr = origName;
-        CharString origNameLanguage = ulocimp_getLanguage(tempNamePtr, &tempNamePtr, err);
-        if (*tempNamePtr == '_') {
-            ++tempNamePtr;
-        }
-        CharString origNameScript = ulocimp_getScript(origName, nullptr, err);
+        CharString origNameLanguage;
+        CharString origNameScript;
+        ulocimp_getSubtags(origName, &origNameLanguage, &origNameScript, nullptr, nullptr, nullptr, err);
         if (!origNameScript.isEmpty()) {
             workingLocale.append(language, err).append("_", err).append(origNameScript, err);
         } else {
@@ -271,7 +273,7 @@ static bool getParentLocaleID(char *name, const char *origName, UResOpenType ope
         // - if not, return false to continue up the chain
         // (we don't do this for other open types for the same reason we don't look things up in the parent
         // locale table for other open types-- see the reference to UTS #35 above)
-        if (openType != URES_OPEN_LOCALE_DEFAULT_ROOT || getDefaultScript(language, CharString()) == script.toStringPiece()) {
+        if (openType != URES_OPEN_LOCALE_DEFAULT_ROOT || getDefaultScript(language, CharString()) == script) {
             workingLocale.append(language, err);
         } else {
             return false;
@@ -1707,7 +1709,7 @@ U_CAPI int32_t U_EXPORT2 ures_getSize(const UResourceBundle *resB) {
 
 static const char16_t* ures_getStringWithAlias(const UResourceBundle *resB, Resource r, int32_t sIndex, int32_t *len, UErrorCode *status) {
   if(RES_GET_TYPE(r) == URES_ALIAS) {
-    const char16_t* result = 0;
+    const char16_t* result = nullptr;
     UResourceBundle *tempRes = ures_getByIndex(resB, sIndex, nullptr, status);
     result = ures_getString(tempRes, len, status);
     ures_close(tempRes);
@@ -2351,7 +2353,66 @@ struct GetAllChildrenSink : public ResourceSink {
                     aliasedValue.setData(aliasRB->getResData());
                     aliasedValue.setValidLocaleDataEntry(aliasRB->fValidLocaleDataEntry);
                     aliasedValue.setResource(aliasRB->fRes, ResourceTracer(aliasRB));
-                    dest.put(key, aliasedValue, isRoot, errorCode);
+                    
+                    if (aliasedValue.getType() != URES_TABLE) {
+                        dest.put(key, aliasedValue, isRoot, errorCode);
+                    } else {
+                        // if the resource we're aliasing over to is a table, the sink might iterate over its contents.
+                        // If it does, it'll get only the things defined in the actual alias target, not the things
+                        // the target inherits from its parent resources.  So we walk the parent chain for the *alias target*,
+                        // calling dest.put() for each of the parent tables we could be inheriting from.  This means
+                        // that dest.put() has to iterate over the children of multiple tables to get all of the inherited
+                        // resource values, but it already has to do that to handle normal vertical inheritance.
+                        UResType aliasedValueType = URES_TABLE;
+                        CharString tablePath;
+                        tablePath.append(aliasRB->fResPath, errorCode);
+                        const char* parentKey = key; // dest.put() changes the key
+                        dest.put(parentKey, aliasedValue, isRoot, errorCode);
+                        UResourceDataEntry* entry = aliasRB->fData;
+                        Resource res = aliasRB->fRes;
+                        while (aliasedValueType == URES_TABLE && entry->fParent != nullptr) {
+                            CharString localPath;
+                            localPath.copyFrom(tablePath, errorCode);
+                            char* localPathAsCharPtr = localPath.data();
+                            const char* childKey;
+                            entry = entry->fParent;
+                            res = entry->fData.rootRes;
+                            Resource newRes = res_findResource(&entry->fData, res, &localPathAsCharPtr, &childKey);
+                            if (newRes != RES_BOGUS) {
+                                aliasedValue.setData(entry->fData);
+                                // TODO: do I also need to call aliasedValue.setValueLocaleDataEntry() ?
+                                aliasedValue.setResource(newRes, ResourceTracer(aliasRB)); // probably wrong to use aliasRB here
+                                aliasedValueType = aliasedValue.getType();
+                                if (aliasedValueType == URES_ALIAS) {
+                                    // in a few rare cases, when we get to the root resource bundle, the resource in question
+                                    // won't be an actual table, but will instead be an alias to a table.  That is, we have
+                                    // two aliases in the inheritance path.  (For some locales, such as Zulu, we see this with
+                                    // children of the "fields" resource: "day-narrow" aliases to "day-short", which aliases
+                                    // to "day".)  When this happens, we need to make sure we follow all the aliases.
+                                    ResourceDataValue& rdv2 = static_cast<ResourceDataValue&>(aliasedValue);
+                                    aliasRB = getAliasTargetAsResourceBundle(rdv2.getData(), rdv2.getResource(), nullptr, -1,
+                                                                             rdv2.getValidLocaleDataEntry(), nullptr, 0,
+                                                                             stackTempBundle.getAlias(), &errorCode);
+                                    tablePath.clear();
+                                    tablePath.append(aliasRB->fResPath, errorCode);
+                                    entry = aliasRB->fData;
+                                    res = aliasRB->fRes;
+                                    aliasedValue.setData(entry->fData);
+                                    // TODO: do I also need to call aliasedValue.setValueLocaleDataEntry() ?
+                                    aliasedValue.setResource(res, ResourceTracer(aliasRB)); // probably wrong to use aliasRB here
+                                    aliasedValueType = aliasedValue.getType();
+                                }
+                                if (aliasedValueType == URES_TABLE) {
+                                    dest.put(parentKey, aliasedValue, isRoot, errorCode);
+                                } else {
+                                    // once we've followed the alias, the resource we're looking at really should
+                                    // be a table
+                                    errorCode = U_INTERNAL_PROGRAM_ERROR;
+                                    return;
+                                }
+                            }
+                        }
+                    }
                 }
             } else {
                 dest.put(key, value, isRoot, errorCode);
@@ -2513,7 +2574,7 @@ U_CAPI const char16_t* U_EXPORT2 ures_getStringByKey(const UResourceBundle *resB
                         return res_getString({resB, key}, &dataEntry->fData, res, len);
                     case URES_ALIAS:
                       {
-                        const char16_t* result = 0;
+                        const char16_t* result = nullptr;
                         UResourceBundle *tempRes = ures_getByKey(resB, inKey, nullptr, status);
                         result = ures_getString(tempRes, len, status);
                         ures_close(tempRes);
@@ -2535,7 +2596,7 @@ U_CAPI const char16_t* U_EXPORT2 ures_getStringByKey(const UResourceBundle *resB
                 return res_getString({resB, key}, &resB->getResData(), res, len);
             case URES_ALIAS:
               {
-                const char16_t* result = 0;
+                const char16_t* result = nullptr;
                 UResourceBundle *tempRes = ures_getByKey(resB, inKey, nullptr, status);
                 result = ures_getString(tempRes, len, status);
                 ures_close(tempRes);
@@ -2657,13 +2718,12 @@ ures_openWithType(UResourceBundle *r, const char* path, const char* localeID,
     UResourceDataEntry *entry;
     if(openType != URES_OPEN_DIRECT) {
         /* first "canonicalize" the locale ID */
-        char canonLocaleID[ULOC_FULLNAME_CAPACITY];
-        uloc_getBaseName(localeID, canonLocaleID, UPRV_LENGTHOF(canonLocaleID), status);
-        if(U_FAILURE(*status) || *status == U_STRING_NOT_TERMINATED_WARNING) {
+        CharString canonLocaleID = ulocimp_getBaseName(localeID, *status);
+        if(U_FAILURE(*status)) {
             *status = U_ILLEGAL_ARGUMENT_ERROR;
             return nullptr;
         }
-        entry = entryOpen(path, canonLocaleID, openType, status);
+        entry = entryOpen(path, canonLocaleID.data(), openType, status);
     } else {
         entry = entryOpenDirect(path, localeID, status);
     }
@@ -2889,7 +2949,7 @@ ures_loc_nextLocale(UEnumeration* en,
     UResourceBundle *k = nullptr;
     const char *result = nullptr;
     int32_t len = 0;
-    if(ures_hasNext(res) && (k = ures_getNextResource(res, &ctx->curr, status)) != 0) {
+    if (ures_hasNext(res) && (k = ures_getNextResource(res, &ctx->curr, status)) != nullptr) {
         result = ures_getKey(k);
         len = (int32_t)uprv_strlen(result);
     }
@@ -2974,44 +3034,66 @@ static UBool isLocaleInList(UEnumeration *locEnum, const char *locToSearch, UErr
     return false;
 }
 
+static void getParentForFunctionalEquivalent(const char*      localeID,
+                                             UResourceBundle* res,
+                                             UResourceBundle* bund1,
+                                             CharString&      parent) {
+    // Get parent.
+    // First check for a parent from %%Parent resource (Note that in resource trees
+    // such as collation, data may have different parents than in parentLocales).
+    UErrorCode subStatus = U_ZERO_ERROR;
+    parent.clear();
+    if (res != nullptr) {
+        ures_getByKey(res, "%%Parent", bund1, &subStatus);
+        if (U_SUCCESS(subStatus)) {
+            int32_t length16;
+            const char16_t* s16 = ures_getString(bund1, &length16, &subStatus);
+            parent.appendInvariantChars(s16, length16, subStatus);
+        }
+    }
+    
+    // If none there, use normal truncation parent
+    if (U_FAILURE(subStatus) || parent.isEmpty()) {
+        subStatus = U_ZERO_ERROR;
+        parent = ulocimp_getParent(localeID, subStatus);
+    }
+}
+
 U_CAPI int32_t U_EXPORT2
 ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
                              const char *path, const char *resName, const char *keyword, const char *locid,
                              UBool *isAvailable, UBool omitDefault, UErrorCode *status)
 {
-    char kwVal[1024] = ""; /* value of keyword 'keyword' */
-    char defVal[1024] = ""; /* default value for given locale */
-    char defLoc[1024] = ""; /* default value for given locale */
-    char base[1024] = ""; /* base locale */
-    char found[1024] = "";
-    char parent[1024] = "";
-    char full[1024] = "";
+    CharString defVal; /* default value for given locale */
+    CharString defLoc; /* default value for given locale */
+    CharString found;
+    CharString parent;
+    CharString full;
     UResourceBundle bund1, bund2;
     UResourceBundle *res = nullptr;
     UErrorCode subStatus = U_ZERO_ERROR;
     int32_t length = 0;
     if(U_FAILURE(*status)) return 0;
-    uloc_getKeywordValue(locid, keyword, kwVal, 1024-1,&subStatus);
-    if(!uprv_strcmp(kwVal, DEFAULT_TAG)) {
-        kwVal[0]=0;
+    CharString kwVal = ulocimp_getKeywordValue(locid, keyword, subStatus);
+    if(kwVal == DEFAULT_TAG) {
+        kwVal.clear();
     }
-    uloc_getBaseName(locid, base, 1024-1,&subStatus);
+    CharString base = ulocimp_getBaseName(locid, subStatus);
 #if defined(URES_TREE_DEBUG)
     fprintf(stderr, "getFunctionalEquivalent: \"%s\" [%s=%s] in %s - %s\n", 
-            locid, keyword, kwVal, base, u_errorName(subStatus));
+            locid, keyword, kwVal.data(), base.data(), u_errorName(subStatus));
 #endif
     ures_initStackObject(&bund1);
     ures_initStackObject(&bund2);
-    
-    
-    uprv_strcpy(parent, base);
-    uprv_strcpy(found, base);
 
-    if(isAvailable) { 
+    parent.copyFrom(base, subStatus);
+    found.copyFrom(base, subStatus);
+
+    if(isAvailable) {
         UEnumeration *locEnum = ures_openAvailableLocales(path, &subStatus);
         *isAvailable = true;
         if (U_SUCCESS(subStatus)) {
-            *isAvailable = isLocaleInList(locEnum, parent, &subStatus);
+            *isAvailable = isLocaleInList(locEnum, parent.data(), &subStatus);
         }
         uenum_close(locEnum);
     }
@@ -3023,7 +3105,7 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
     
     do {
         subStatus = U_ZERO_ERROR;
-        res = ures_open(path, parent, &subStatus);
+        res = ures_open(path, parent.data(), &subStatus);
         if(((subStatus == U_USING_FALLBACK_WARNING) ||
             (subStatus == U_USING_DEFAULT_WARNING)) && isAvailable)
         {
@@ -3032,7 +3114,7 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
         isAvailable = nullptr; /* only want to set this the first time around */
         
 #if defined(URES_TREE_DEBUG)
-        fprintf(stderr, "%s;%s -> %s [%s]\n", path?path:"ICUDATA", parent, u_errorName(subStatus), ures_getLocale(res, &subStatus));
+        fprintf(stderr, "%s;%s -> %s [%s]\n", path?path:"ICUDATA", parent.data(), u_errorName(subStatus), ures_getLocale(res, &subStatus));
 #endif
         if(U_FAILURE(subStatus)) {
             *status = subStatus;
@@ -3044,21 +3126,21 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
                 /* look for default item */
 #if defined(URES_TREE_DEBUG)
                 fprintf(stderr, "%s;%s : loaded default -> %s\n",
-                    path?path:"ICUDATA", parent, u_errorName(subStatus));
+                    path?path:"ICUDATA", parent.data(), u_errorName(subStatus));
 #endif
                 defUstr = ures_getStringByKey(&bund1, DEFAULT_TAG, &defLen, &subStatus);
                 if(U_SUCCESS(subStatus) && defLen) {
-                    u_UCharsToChars(defUstr, defVal, u_strlen(defUstr));
+                    defVal.clear().appendInvariantChars(defUstr, defLen, subStatus);
 #if defined(URES_TREE_DEBUG)
                     fprintf(stderr, "%s;%s -> default %s=%s,  %s\n", 
-                        path?path:"ICUDATA", parent, keyword, defVal, u_errorName(subStatus));
+                        path?path:"ICUDATA", parent.data(), keyword, defVal.data(), u_errorName(subStatus));
 #endif
-                    uprv_strcpy(defLoc, parent);
-                    if(kwVal[0]==0) {
-                        uprv_strcpy(kwVal, defVal);
+                    defLoc.copyFrom(parent, subStatus);
+                    if(kwVal.isEmpty()) {
+                        kwVal.append(defVal, subStatus);
 #if defined(URES_TREE_DEBUG)
                         fprintf(stderr, "%s;%s -> kwVal =  %s\n", 
-                            path?path:"ICUDATA", parent, keyword, kwVal);
+                            path?path:"ICUDATA", parent.data(), keyword, kwVal.data());
 #endif
                     }
                 }
@@ -3068,20 +3150,23 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
         subStatus = U_ZERO_ERROR;
 
         if (res != nullptr) {
-            uprv_strcpy(found, ures_getLocaleByType(res, ULOC_VALID_LOCALE, &subStatus));
+            found.clear().append(ures_getLocaleByType(res, ULOC_VALID_LOCALE, &subStatus), subStatus);
         }
 
-        uloc_getParent(found,parent,sizeof(parent),&subStatus);
+        if (found != parent) {
+            parent.copyFrom(found, subStatus);
+        } else {
+            getParentForFunctionalEquivalent(found.data(),res,&bund1,parent);
+        }
         ures_close(res);
-    } while(!defVal[0] && *found && uprv_strcmp(found, "root") != 0 && U_SUCCESS(*status));
+    } while(defVal.isEmpty() && !found.isEmpty() && found != "root" && U_SUCCESS(*status));
     
     /* Now, see if we can find the kwVal collator.. start the search over.. */
-    uprv_strcpy(parent, base);
-    uprv_strcpy(found, base);
-    
+    parent.copyFrom(base, subStatus);
+    found.copyFrom(base, subStatus);
+
     do {
-        subStatus = U_ZERO_ERROR;
-        res = ures_open(path, parent, &subStatus);
+        res = ures_open(path, parent.data(), &subStatus);
         if((subStatus == U_USING_FALLBACK_WARNING) && isAvailable) {
             *isAvailable = false;
         }
@@ -3089,7 +3174,7 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
         
 #if defined(URES_TREE_DEBUG)
         fprintf(stderr, "%s;%s -> %s (looking for %s)\n", 
-            path?path:"ICUDATA", parent, u_errorName(subStatus), kwVal);
+            path?path:"ICUDATA", parent.data(), u_errorName(subStatus), kwVal.data());
 #endif
         if(U_FAILURE(subStatus)) {
             *status = subStatus;
@@ -3099,70 +3184,92 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
 /**/ fprintf(stderr,"@%d [%s] %s\n", __LINE__, resName, u_errorName(subStatus));
 #endif
             if(subStatus == U_ZERO_ERROR) {
-                ures_getByKey(&bund1, kwVal, &bund2, &subStatus);
+                ures_getByKey(&bund1, kwVal.data(), &bund2, &subStatus);
 #if defined(URES_TREE_DEBUG)
-/**/ fprintf(stderr,"@%d [%s] %s\n", __LINE__, kwVal, u_errorName(subStatus));
+/**/ fprintf(stderr,"@%d [%s] %s\n", __LINE__, kwVal.data(), u_errorName(subStatus));
 #endif
                 if(subStatus == U_ZERO_ERROR) {
 #if defined(URES_TREE_DEBUG)
                     fprintf(stderr, "%s;%s -> full0 %s=%s,  %s\n", 
-                        path?path:"ICUDATA", parent, keyword, kwVal, u_errorName(subStatus));
+                        path?path:"ICUDATA", parent.data(), keyword, kwVal.data(), u_errorName(subStatus));
 #endif
-                    uprv_strcpy(full, parent);
-                    if(*full == 0) {
-                        uprv_strcpy(full, "root");
+                    if (parent.isEmpty()) {
+                        full.clear().append("root", subStatus);
+                    } else {
+                        full.copyFrom(parent, subStatus);
                     }
                         /* now, recalculate default kw if need be */
-                        if(uprv_strlen(defLoc) > uprv_strlen(full)) {
+                        if(defLoc.length() > full.length()) {
                           const char16_t *defUstr;
                           int32_t defLen;
                           /* look for default item */
 #if defined(URES_TREE_DEBUG)
                             fprintf(stderr, "%s;%s -> recalculating Default0\n", 
-                                    path?path:"ICUDATA", full);
+                                    path?path:"ICUDATA", full.data());
 #endif
                           defUstr = ures_getStringByKey(&bund1, DEFAULT_TAG, &defLen, &subStatus);
                           if(U_SUCCESS(subStatus) && defLen) {
-                            u_UCharsToChars(defUstr, defVal, u_strlen(defUstr));
+                            defVal.clear().appendInvariantChars(defUstr, defLen, subStatus);
 #if defined(URES_TREE_DEBUG)
                             fprintf(stderr, "%s;%s -> default0 %s=%s,  %s\n", 
-                                    path?path:"ICUDATA", full, keyword, defVal, u_errorName(subStatus));
+                                    path?path:"ICUDATA", full.data(), keyword, defVal.data(), u_errorName(subStatus));
 #endif
-                            uprv_strcpy(defLoc, full);
+                            defLoc.copyFrom(full, subStatus);
                           }
                         } /* end of recalculate default KW */
 #if defined(URES_TREE_DEBUG)
                         else {
-                          fprintf(stderr, "No trim0,  %s <= %s\n", defLoc, full);
+                          fprintf(stderr, "No trim0,  %s <= %s\n", defLoc.data(), full.data());
                         }
 #endif
                 } else {
 #if defined(URES_TREE_DEBUG)
                     fprintf(stderr, "err=%s in %s looking for %s\n", 
-                        u_errorName(subStatus), parent, kwVal);
+                        u_errorName(subStatus), parent.data(), kwVal.data());
 #endif
                 }
             }
         }
         
         subStatus = U_ZERO_ERROR;
-        
-        uprv_strcpy(found, parent);
-        uloc_getParent(found,parent,1023,&subStatus);
+        UBool haveFound = false;
+        // At least for collations which may be aliased, we need to use the VALID locale
+        // as the parent instead of just truncating, as long as the VALID locale is not
+        // root and has a different language than the parent. Use of the VALID locale
+        // here is similar to the procedure used at the end of the previous do-while loop
+        // for all resource types.
+        if (res != nullptr && uprv_strcmp(resName, "collations") == 0) {
+            const char *validLoc = ures_getLocaleByType(res, ULOC_VALID_LOCALE, &subStatus);
+            if (U_SUCCESS(subStatus) && validLoc != nullptr && validLoc[0] != 0 && uprv_strcmp(validLoc, "root") != 0) {
+                CharString validLang = ulocimp_getLanguage(validLoc, subStatus);
+                CharString parentLang = ulocimp_getLanguage(parent.data(), subStatus);
+                if (U_SUCCESS(subStatus) && validLang != parentLang) {
+                    // validLoc is not root and has a different language than parent, use it instead
+                    found.clear().append(validLoc, subStatus);
+                    haveFound = true;
+                }
+            }
+            subStatus = U_ZERO_ERROR;
+        }
+        if (!haveFound) {
+            found.copyFrom(parent, subStatus);
+        }
+
+        getParentForFunctionalEquivalent(found.data(),res,&bund1,parent);
         ures_close(res);
-    } while(!full[0] && *found && U_SUCCESS(*status));
-    
-    if((full[0]==0) && uprv_strcmp(kwVal, defVal)) {
+        subStatus = U_ZERO_ERROR;
+    } while(full.isEmpty() && !found.isEmpty() && U_SUCCESS(*status));
+
+    if(full.isEmpty() && kwVal != defVal) {
 #if defined(URES_TREE_DEBUG)
-        fprintf(stderr, "Failed to locate kw %s - try default %s\n", kwVal, defVal);
+        fprintf(stderr, "Failed to locate kw %s - try default %s\n", kwVal.data(), defVal.data());
 #endif
-        uprv_strcpy(kwVal, defVal);
-        uprv_strcpy(parent, base);
-        uprv_strcpy(found, base);
-        
+        kwVal.clear().append(defVal, subStatus);
+        parent.copyFrom(base, subStatus);
+        found.copyFrom(base, subStatus);
+
         do { /* search for 'default' named item */
-            subStatus = U_ZERO_ERROR;
-            res = ures_open(path, parent, &subStatus);
+            res = ures_open(path, parent.data(), &subStatus);
             if((subStatus == U_USING_FALLBACK_WARNING) && isAvailable) {
                 *isAvailable = false;
             }
@@ -3170,91 +3277,95 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
             
 #if defined(URES_TREE_DEBUG)
             fprintf(stderr, "%s;%s -> %s (looking for default %s)\n",
-                path?path:"ICUDATA", parent, u_errorName(subStatus), kwVal);
+                path?path:"ICUDATA", parent.data(), u_errorName(subStatus), kwVal.data());
 #endif
             if(U_FAILURE(subStatus)) {
                 *status = subStatus;
             } else if(subStatus == U_ZERO_ERROR) {
                 ures_getByKey(res,resName,&bund1, &subStatus);
                 if(subStatus == U_ZERO_ERROR) {
-                    ures_getByKey(&bund1, kwVal, &bund2, &subStatus);
+                    ures_getByKey(&bund1, kwVal.data(), &bund2, &subStatus);
                     if(subStatus == U_ZERO_ERROR) {
 #if defined(URES_TREE_DEBUG)
                         fprintf(stderr, "%s;%s -> full1 %s=%s,  %s\n", path?path:"ICUDATA",
-                            parent, keyword, kwVal, u_errorName(subStatus));
+                            parent.data(), keyword, kwVal.data(), u_errorName(subStatus));
 #endif
-                        uprv_strcpy(full, parent);
-                        if(*full == 0) {
-                            uprv_strcpy(full, "root");
+                        if (parent.isEmpty()) {
+                            full.clear().append("root", subStatus);
+                        } else {
+                            full.copyFrom(parent, subStatus);
                         }
                         
                         /* now, recalculate default kw if need be */
-                        if(uprv_strlen(defLoc) > uprv_strlen(full)) {
+                        if(defLoc.length() > full.length()) {
                           const char16_t *defUstr;
                           int32_t defLen;
                           /* look for default item */
 #if defined(URES_TREE_DEBUG)
                             fprintf(stderr, "%s;%s -> recalculating Default1\n", 
-                                    path?path:"ICUDATA", full);
+                                    path?path:"ICUDATA", full.data());
 #endif
                           defUstr = ures_getStringByKey(&bund1, DEFAULT_TAG, &defLen, &subStatus);
                           if(U_SUCCESS(subStatus) && defLen) {
-                            u_UCharsToChars(defUstr, defVal, u_strlen(defUstr));
+                            defVal.clear().appendInvariantChars(defUstr, defLen, subStatus);
 #if defined(URES_TREE_DEBUG)
                             fprintf(stderr, "%s;%s -> default %s=%s,  %s\n", 
-                                    path?path:"ICUDATA", full, keyword, defVal, u_errorName(subStatus));
+                                    path?path:"ICUDATA", full.data(), keyword, defVal.data(), u_errorName(subStatus));
 #endif
-                            uprv_strcpy(defLoc, full);
+                            defLoc.copyFrom(full, subStatus);
                           }
                         } /* end of recalculate default KW */
 #if defined(URES_TREE_DEBUG)
                         else {
-                          fprintf(stderr, "No trim1,  %s <= %s\n", defLoc, full);
+                          fprintf(stderr, "No trim1,  %s <= %s\n", defLoc.data(), full.data());
                         }
 #endif
                     }
                 }
             }
-            subStatus = U_ZERO_ERROR;
             
-            uprv_strcpy(found, parent);
-            uloc_getParent(found,parent,1023,&subStatus);
+            subStatus = U_ZERO_ERROR;
+            found.copyFrom(parent, subStatus);
+            getParentForFunctionalEquivalent(found.data(),res,&bund1,parent);
             ures_close(res);
-        } while(!full[0] && *found && U_SUCCESS(*status));
+            subStatus = U_ZERO_ERROR;
+        } while(full.isEmpty() && !found.isEmpty() && U_SUCCESS(*status));
     }
     
     if(U_SUCCESS(*status)) {
-        if(!full[0]) {
+        if(full.isEmpty()) {
 #if defined(URES_TREE_DEBUG)
-          fprintf(stderr, "Still could not load keyword %s=%s\n", keyword, kwVal);
+          fprintf(stderr, "Still could not load keyword %s=%s\n", keyword, kwVal.data());
 #endif
           *status = U_MISSING_RESOURCE_ERROR;
         } else if(omitDefault) {
 #if defined(URES_TREE_DEBUG)
-          fprintf(stderr,"Trim? full=%s, defLoc=%s, found=%s\n", full, defLoc, found);
+          fprintf(stderr,"Trim? full=%s, defLoc=%s, found=%s\n", full.data(), defLoc.data(), found.data());
 #endif        
-          if(uprv_strlen(defLoc) <= uprv_strlen(full)) {
+          if(defLoc.length() <= full.length()) {
             /* found the keyword in a *child* of where the default tag was present. */
-            if(!uprv_strcmp(kwVal, defVal)) { /* if the requested kw is default, */
+            if(kwVal == defVal) { /* if the requested kw is default, */
               /* and the default is in or in an ancestor of the current locale */
 #if defined(URES_TREE_DEBUG)
-              fprintf(stderr, "Removing unneeded var %s=%s\n", keyword, kwVal);
+              fprintf(stderr, "Removing unneeded var %s=%s\n", keyword, kwVal.data());
 #endif
-              kwVal[0]=0;
+              kwVal.clear();
             }
           }
         }
-        uprv_strcpy(found, full);
-        if(kwVal[0]) {
-            uprv_strcat(found, "@");
-            uprv_strcat(found, keyword);
-            uprv_strcat(found, "=");
-            uprv_strcat(found, kwVal);
+        found.copyFrom(full, subStatus);
+        if(!kwVal.isEmpty()) {
+            found
+                .append("@", subStatus)
+                .append(keyword, subStatus)
+                .append("=", subStatus)
+                .append(kwVal, subStatus);
         } else if(!omitDefault) {
-            uprv_strcat(found, "@");
-            uprv_strcat(found, keyword);
-            uprv_strcat(found, "=");
-            uprv_strcat(found, defVal);
+            found
+                .append("@", subStatus)
+                .append(keyword, subStatus)
+                .append("=", subStatus)
+                .append(defVal, subStatus);
         }
     }
     /* we found the default locale - no need to repeat it.*/
@@ -3262,12 +3373,12 @@ ures_getFunctionalEquivalent(char *result, int32_t resultCapacity,
     ures_close(&bund1);
     ures_close(&bund2);
     
-    length = (int32_t)uprv_strlen(found);
+    length = found.length();
 
     if(U_SUCCESS(*status)) {
         int32_t copyLength = uprv_min(length, resultCapacity);
         if(copyLength>0) {
-            uprv_strncpy(result, found, copyLength);
+            found.extract(result, copyLength, subStatus);
         }
         if(length == 0) {
           *status = U_MISSING_RESOURCE_ERROR; 
@@ -3310,8 +3421,8 @@ ures_getKeywordValues(const char *path, const char *keyword, UErrorCode *status)
     
     valuesBuf[0]=0;
     valuesBuf[1]=0;
-    
-    while((locale = uenum_next(locs, &locLen, status)) != 0) {
+
+    while ((locale = uenum_next(locs, &locLen, status)) != nullptr) {
         UResourceBundle   *bund = nullptr;
         UResourceBundle   *subPtr = nullptr;
         UErrorCode subStatus = U_ZERO_ERROR; /* don't fail if a bundle is unopenable */
@@ -3335,8 +3446,8 @@ ures_getKeywordValues(const char *path, const char *keyword, UErrorCode *status)
             bund = nullptr;
             continue;
         }
-        
-        while((subPtr = ures_getNextResource(&item,&subItem,&subStatus)) != 0
+
+        while ((subPtr = ures_getNextResource(&item, &subItem, &subStatus)) != nullptr
             && U_SUCCESS(subStatus)) {
             const char *k;
             int32_t i;