Adding upstream version 115.8.0esr.upstream/115.8.0esr

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 902 insertions, 0 deletions

diff --git a/intl/icu/source/common/locdispnames.cpp b/intl/icu/source/common/locdispnames.cpp
new file mode 100644
index 0000000000..3ec1b81c81
--- /dev/null
+++ b/intl/icu/source/common/locdispnames.cpp
@@ -0,0 +1,902 @@
+// © 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+*******************************************************************************
+*
+*   Copyright (C) 1997-2016, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+*
+*******************************************************************************
+*   file name:  locdispnames.cpp
+*   encoding:   UTF-8
+*   tab size:   8 (not used)
+*   indentation:4
+*
+*   created on: 2010feb25
+*   created by: Markus W. Scherer
+*
+*   Code for locale display names, separated out from other .cpp files
+*   that then do not depend on resource bundle code and display name data.
+*/
+
+#include "unicode/utypes.h"
+#include "unicode/brkiter.h"
+#include "unicode/locid.h"
+#include "unicode/uenum.h"
+#include "unicode/uloc.h"
+#include "unicode/ures.h"
+#include "unicode/ustring.h"
+#include "bytesinkutil.h"
+#include "charstr.h"
+#include "cmemory.h"
+#include "cstring.h"
+#include "putilimp.h"
+#include "ulocimp.h"
+#include "uresimp.h"
+#include "ureslocs.h"
+#include "ustr_imp.h"
+
+// C++ API ----------------------------------------------------------------- ***
+
+U_NAMESPACE_BEGIN
+
+UnicodeString&
+Locale::getDisplayLanguage(UnicodeString& dispLang) const
+{
+    return this->getDisplayLanguage(getDefault(), dispLang);
+}
+
+/*We cannot make any assumptions on the size of the output display strings
+* Yet, since we are calling through to a C API, we need to set limits on
+* buffer size. For all the following getDisplay functions we first attempt
+* to fill up a stack allocated buffer. If it is to small we heap allocated
+* the exact buffer we need copy it to the UnicodeString and delete it*/
+
+UnicodeString&
+Locale::getDisplayLanguage(const Locale &displayLocale,
+                           UnicodeString &result) const {
+    char16_t *buffer;
+    UErrorCode errorCode=U_ZERO_ERROR;
+    int32_t length;
+
+    buffer=result.getBuffer(ULOC_FULLNAME_CAPACITY);
+    if(buffer==0) {
+        result.truncate(0);
+        return result;
+    }
+
+    length=uloc_getDisplayLanguage(fullName, displayLocale.fullName,
+                                   buffer, result.getCapacity(),
+                                   &errorCode);
+    result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+
+    if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
+        buffer=result.getBuffer(length);
+        if(buffer==0) {
+            result.truncate(0);
+            return result;
+        }
+        errorCode=U_ZERO_ERROR;
+        length=uloc_getDisplayLanguage(fullName, displayLocale.fullName,
+                                       buffer, result.getCapacity(),
+                                       &errorCode);
+        result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+    }
+
+    return result;
+}
+
+UnicodeString&
+Locale::getDisplayScript(UnicodeString& dispScript) const
+{
+    return this->getDisplayScript(getDefault(), dispScript);
+}
+
+UnicodeString&
+Locale::getDisplayScript(const Locale &displayLocale,
+                          UnicodeString &result) const {
+    char16_t *buffer;
+    UErrorCode errorCode=U_ZERO_ERROR;
+    int32_t length;
+
+    buffer=result.getBuffer(ULOC_FULLNAME_CAPACITY);
+    if(buffer==0) {
+        result.truncate(0);
+        return result;
+    }
+
+    length=uloc_getDisplayScript(fullName, displayLocale.fullName,
+                                  buffer, result.getCapacity(),
+                                  &errorCode);
+    result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+
+    if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
+        buffer=result.getBuffer(length);
+        if(buffer==0) {
+            result.truncate(0);
+            return result;
+        }
+        errorCode=U_ZERO_ERROR;
+        length=uloc_getDisplayScript(fullName, displayLocale.fullName,
+                                      buffer, result.getCapacity(),
+                                      &errorCode);
+        result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+    }
+
+    return result;
+}
+
+UnicodeString&
+Locale::getDisplayCountry(UnicodeString& dispCntry) const
+{
+    return this->getDisplayCountry(getDefault(), dispCntry);
+}
+
+UnicodeString&
+Locale::getDisplayCountry(const Locale &displayLocale,
+                          UnicodeString &result) const {
+    char16_t *buffer;
+    UErrorCode errorCode=U_ZERO_ERROR;
+    int32_t length;
+
+    buffer=result.getBuffer(ULOC_FULLNAME_CAPACITY);
+    if(buffer==0) {
+        result.truncate(0);
+        return result;
+    }
+
+    length=uloc_getDisplayCountry(fullName, displayLocale.fullName,
+                                  buffer, result.getCapacity(),
+                                  &errorCode);
+    result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+
+    if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
+        buffer=result.getBuffer(length);
+        if(buffer==0) {
+            result.truncate(0);
+            return result;
+        }
+        errorCode=U_ZERO_ERROR;
+        length=uloc_getDisplayCountry(fullName, displayLocale.fullName,
+                                      buffer, result.getCapacity(),
+                                      &errorCode);
+        result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+    }
+
+    return result;
+}
+
+UnicodeString&
+Locale::getDisplayVariant(UnicodeString& dispVar) const
+{
+    return this->getDisplayVariant(getDefault(), dispVar);
+}
+
+UnicodeString&
+Locale::getDisplayVariant(const Locale &displayLocale,
+                          UnicodeString &result) const {
+    char16_t *buffer;
+    UErrorCode errorCode=U_ZERO_ERROR;
+    int32_t length;
+
+    buffer=result.getBuffer(ULOC_FULLNAME_CAPACITY);
+    if(buffer==0) {
+        result.truncate(0);
+        return result;
+    }
+
+    length=uloc_getDisplayVariant(fullName, displayLocale.fullName,
+                                  buffer, result.getCapacity(),
+                                  &errorCode);
+    result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+
+    if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
+        buffer=result.getBuffer(length);
+        if(buffer==0) {
+            result.truncate(0);
+            return result;
+        }
+        errorCode=U_ZERO_ERROR;
+        length=uloc_getDisplayVariant(fullName, displayLocale.fullName,
+                                      buffer, result.getCapacity(),
+                                      &errorCode);
+        result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+    }
+
+    return result;
+}
+
+UnicodeString&
+Locale::getDisplayName( UnicodeString& name ) const
+{
+    return this->getDisplayName(getDefault(), name);
+}
+
+UnicodeString&
+Locale::getDisplayName(const Locale &displayLocale,
+                       UnicodeString &result) const {
+    char16_t *buffer;
+    UErrorCode errorCode=U_ZERO_ERROR;
+    int32_t length;
+
+    buffer=result.getBuffer(ULOC_FULLNAME_CAPACITY);
+    if(buffer==0) {
+        result.truncate(0);
+        return result;
+    }
+
+    length=uloc_getDisplayName(fullName, displayLocale.fullName,
+                               buffer, result.getCapacity(),
+                               &errorCode);
+    result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+
+    if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
+        buffer=result.getBuffer(length);
+        if(buffer==0) {
+            result.truncate(0);
+            return result;
+        }
+        errorCode=U_ZERO_ERROR;
+        length=uloc_getDisplayName(fullName, displayLocale.fullName,
+                                   buffer, result.getCapacity(),
+                                   &errorCode);
+        result.releaseBuffer(U_SUCCESS(errorCode) ? length : 0);
+    }
+
+    return result;
+}
+
+#if ! UCONFIG_NO_BREAK_ITERATION
+
+// -------------------------------------
+// Gets the objectLocale display name in the default locale language.
+UnicodeString& U_EXPORT2
+BreakIterator::getDisplayName(const Locale& objectLocale,
+                             UnicodeString& name)
+{
+    return objectLocale.getDisplayName(name);
+}
+
+// -------------------------------------
+// Gets the objectLocale display name in the displayLocale language.
+UnicodeString& U_EXPORT2
+BreakIterator::getDisplayName(const Locale& objectLocale,
+                             const Locale& displayLocale,
+                             UnicodeString& name)
+{
+    return objectLocale.getDisplayName(displayLocale, name);
+}
+
+#endif
+
+
+U_NAMESPACE_END
+
+// C API ------------------------------------------------------------------- ***
+
+U_NAMESPACE_USE
+
+/* ### Constants **************************************************/
+
+/* These strings describe the resources we attempt to load from
+ the locale ResourceBundle data file.*/
+static const char _kLanguages[]       = "Languages";
+static const char _kScripts[]         = "Scripts";
+static const char _kScriptsStandAlone[] = "Scripts%stand-alone";
+static const char _kCountries[]       = "Countries";
+static const char _kVariants[]        = "Variants";
+static const char _kKeys[]            = "Keys";
+static const char _kTypes[]           = "Types";
+//static const char _kRootName[]        = "root";
+static const char _kCurrency[]        = "currency";
+static const char _kCurrencies[]      = "Currencies";
+static const char _kLocaleDisplayPattern[] = "localeDisplayPattern";
+static const char _kPattern[]         = "pattern";
+static const char _kSeparator[]       = "separator";
+
+/* ### Display name **************************************************/
+
+static int32_t
+_getStringOrCopyKey(const char *path, const char *locale,
+                    const char *tableKey, 
+                    const char* subTableKey,
+                    const char *itemKey,
+                    const char *substitute,
+                    char16_t *dest, int32_t destCapacity,
+                    UErrorCode *pErrorCode) {
+    const char16_t *s = nullptr;
+    int32_t length = 0;
+
+    if(itemKey==nullptr) {
+        /* top-level item: normal resource bundle access */
+        icu::LocalUResourceBundlePointer rb(ures_open(path, locale, pErrorCode));
+
+        if(U_SUCCESS(*pErrorCode)) {
+            s=ures_getStringByKey(rb.getAlias(), tableKey, &length, pErrorCode);
+            /* see comment about closing rb near "return item;" in _res_getTableStringWithFallback() */
+        }
+    } else {
+        bool isLanguageCode = (uprv_strncmp(tableKey, _kLanguages, 9) == 0);
+        /* Language code should not be a number. If it is, set the error code. */
+        if (isLanguageCode && uprv_strtol(itemKey, nullptr, 10)) {
+            *pErrorCode = U_MISSING_RESOURCE_ERROR;
+        } else {
+            /* second-level item, use special fallback */
+            s=uloc_getTableStringWithFallback(path, locale,
+                                               tableKey,
+                                               subTableKey,
+                                               itemKey,
+                                               &length,
+                                               pErrorCode);
+            if (U_FAILURE(*pErrorCode) && isLanguageCode && itemKey != nullptr) {
+                // convert itemKey locale code to canonical form and try again, ICU-20870
+                *pErrorCode = U_ZERO_ERROR;
+                Locale canonKey = Locale::createCanonical(itemKey);
+                s=uloc_getTableStringWithFallback(path, locale,
+                                                    tableKey,
+                                                    subTableKey,
+                                                    canonKey.getName(),
+                                                    &length,
+                                                    pErrorCode);
+            }
+        }
+    }
+
+    if(U_SUCCESS(*pErrorCode)) {
+        int32_t copyLength=uprv_min(length, destCapacity);
+        if(copyLength>0 && s != nullptr) {
+            u_memcpy(dest, s, copyLength);
+        }
+    } else {
+        /* no string from a resource bundle: convert the substitute */
+        length=(int32_t)uprv_strlen(substitute);
+        u_charsToUChars(substitute, dest, uprv_min(length, destCapacity));
+        *pErrorCode=U_USING_DEFAULT_WARNING;
+    }
+
+    return u_terminateUChars(dest, destCapacity, length, pErrorCode);
+}
+
+typedef  int32_t U_CALLCONV UDisplayNameGetter(const char *, char *, int32_t, UErrorCode *);
+
+static int32_t
+_getDisplayNameForComponent(const char *locale,
+                            const char *displayLocale,
+                            char16_t *dest, int32_t destCapacity,
+                            UDisplayNameGetter *getter,
+                            const char *tag,
+                            UErrorCode *pErrorCode) {
+    char localeBuffer[ULOC_FULLNAME_CAPACITY*4];
+    int32_t length;
+    UErrorCode localStatus;
+    const char* root = nullptr;
+
+    /* argument checking */
+    if(pErrorCode==nullptr || U_FAILURE(*pErrorCode)) {
+        return 0;
+    }
+
+    if(destCapacity<0 || (destCapacity>0 && dest==nullptr)) {
+        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+
+    localStatus = U_ZERO_ERROR;
+    length=(*getter)(locale, localeBuffer, sizeof(localeBuffer), &localStatus);
+    if(U_FAILURE(localStatus) || localStatus==U_STRING_NOT_TERMINATED_WARNING) {
+        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+    if(length==0) {
+        // For the display name, we treat this as unknown language (ICU-20273).
+        if (getter == uloc_getLanguage) {
+            uprv_strcpy(localeBuffer, "und");
+        } else {
+            return u_terminateUChars(dest, destCapacity, 0, pErrorCode);
+        }
+    }
+
+    root = tag == _kCountries ? U_ICUDATA_REGION : U_ICUDATA_LANG;
+
+    return _getStringOrCopyKey(root, displayLocale,
+                               tag, nullptr, localeBuffer,
+                               localeBuffer,
+                               dest, destCapacity,
+                               pErrorCode);
+}
+
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayLanguage(const char *locale,
+                        const char *displayLocale,
+                        char16_t *dest, int32_t destCapacity,
+                        UErrorCode *pErrorCode) {
+    return _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                uloc_getLanguage, _kLanguages, pErrorCode);
+}
+
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayScript(const char* locale,
+                      const char* displayLocale,
+                      char16_t *dest, int32_t destCapacity,
+                      UErrorCode *pErrorCode)
+{
+    UErrorCode err = U_ZERO_ERROR;
+    int32_t res = _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                uloc_getScript, _kScriptsStandAlone, &err);
+
+    if (destCapacity == 0 && err == U_BUFFER_OVERFLOW_ERROR) {
+        // For preflight, return the max of the value and the fallback.
+        int32_t fallback_res = _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                                                           uloc_getScript, _kScripts, pErrorCode);
+        return (fallback_res > res) ? fallback_res : res;
+    }
+    if ( err == U_USING_DEFAULT_WARNING ) {
+        return _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                                           uloc_getScript, _kScripts, pErrorCode);
+    } else {
+        *pErrorCode = err;
+        return res;
+    }
+}
+
+static int32_t
+uloc_getDisplayScriptInContext(const char* locale,
+                      const char* displayLocale,
+                      char16_t *dest, int32_t destCapacity,
+                      UErrorCode *pErrorCode)
+{
+    return _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                    uloc_getScript, _kScripts, pErrorCode);
+}
+
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayCountry(const char *locale,
+                       const char *displayLocale,
+                       char16_t *dest, int32_t destCapacity,
+                       UErrorCode *pErrorCode) {
+    return _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                uloc_getCountry, _kCountries, pErrorCode);
+}
+
+/*
+ * TODO separate variant1_variant2_variant3...
+ * by getting each tag's display string and concatenating them with ", "
+ * in between - similar to uloc_getDisplayName()
+ */
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayVariant(const char *locale,
+                       const char *displayLocale,
+                       char16_t *dest, int32_t destCapacity,
+                       UErrorCode *pErrorCode) {
+    return _getDisplayNameForComponent(locale, displayLocale, dest, destCapacity,
+                uloc_getVariant, _kVariants, pErrorCode);
+}
+
+/* Instead of having a separate pass for 'special' patterns, reintegrate the two
+ * so we don't get bitten by preflight bugs again.  We can be reasonably efficient
+ * without two separate code paths, this code isn't that performance-critical.
+ *
+ * This code is general enough to deal with patterns that have a prefix or swap the
+ * language and remainder components, since we gave developers enough rope to do such
+ * things if they futz with the pattern data.  But since we don't give them a way to
+ * specify a pattern for arbitrary combinations of components, there's not much use in
+ * that.  I don't think our data includes such patterns, the only variable I know if is
+ * whether there is a space before the open paren, or not.  Oh, and zh uses different
+ * chars than the standard open/close paren (which ja and ko use, btw).
+ */
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayName(const char *locale,
+                    const char *displayLocale,
+                    char16_t *dest, int32_t destCapacity,
+                    UErrorCode *pErrorCode)
+{
+    static const char16_t defaultSeparator[9] = { 0x007b, 0x0030, 0x007d, 0x002c, 0x0020, 0x007b, 0x0031, 0x007d, 0x0000 }; /* "{0}, {1}" */
+    static const char16_t sub0[4] = { 0x007b, 0x0030, 0x007d , 0x0000 } ; /* {0} */
+    static const char16_t sub1[4] = { 0x007b, 0x0031, 0x007d , 0x0000 } ; /* {1} */
+    static const int32_t subLen = 3;
+    static const char16_t defaultPattern[10] = {
+        0x007b, 0x0030, 0x007d, 0x0020, 0x0028, 0x007b, 0x0031, 0x007d, 0x0029, 0x0000
+    }; /* {0} ({1}) */
+    static const int32_t defaultPatLen = 9;
+    static const int32_t defaultSub0Pos = 0;
+    static const int32_t defaultSub1Pos = 5;
+
+    int32_t length; /* of formatted result */
+
+    const char16_t *separator;
+    int32_t sepLen = 0;
+    const char16_t *pattern;
+    int32_t patLen = 0;
+    int32_t sub0Pos, sub1Pos;
+    
+    char16_t formatOpenParen         = 0x0028; // (
+    char16_t formatReplaceOpenParen  = 0x005B; // [
+    char16_t formatCloseParen        = 0x0029; // )
+    char16_t formatReplaceCloseParen = 0x005D; // ]
+
+    UBool haveLang = true; /* assume true, set false if we find we don't have
+                              a lang component in the locale */
+    UBool haveRest = true; /* assume true, set false if we find we don't have
+                              any other component in the locale */
+    UBool retry = false; /* set true if we need to retry, see below */
+
+    int32_t langi = 0; /* index of the language substitution (0 or 1), virtually always 0 */
+
+    if(pErrorCode==nullptr || U_FAILURE(*pErrorCode)) {
+        return 0;
+    }
+
+    if(destCapacity<0 || (destCapacity>0 && dest==nullptr)) {
+        *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+
+    {
+        UErrorCode status = U_ZERO_ERROR;
+
+        icu::LocalUResourceBundlePointer locbundle(
+                ures_open(U_ICUDATA_LANG, displayLocale, &status));
+        icu::LocalUResourceBundlePointer dspbundle(
+                ures_getByKeyWithFallback(locbundle.getAlias(), _kLocaleDisplayPattern, nullptr, &status));
+
+        separator=ures_getStringByKeyWithFallback(dspbundle.getAlias(), _kSeparator, &sepLen, &status);
+        pattern=ures_getStringByKeyWithFallback(dspbundle.getAlias(), _kPattern, &patLen, &status);
+    }
+
+    /* If we couldn't find any data, then use the defaults */
+    if(sepLen == 0) {
+       separator = defaultSeparator;
+    }
+    /* #10244: Even though separator is now a pattern, it is awkward to handle it as such
+     * here since we are trying to build the display string in place in the dest buffer,
+     * and to handle it as a pattern would entail having separate storage for the
+     * substrings that need to be combined (the first of which may be the result of
+     * previous such combinations). So for now we continue to treat the portion between
+     * {0} and {1} as a string to be appended when joining substrings, ignoring anything
+     * that is before {0} or after {1} (no existing separator pattern has any such thing).
+     * This is similar to how pattern is handled below.
+     */
+    {
+        char16_t *p0=u_strstr(separator, sub0);
+        char16_t *p1=u_strstr(separator, sub1);
+        if (p0==nullptr || p1==nullptr || p1<p0) {
+            *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
+            return 0;
+        }
+        separator = (const char16_t *)p0 + subLen;
+        sepLen = static_cast<int32_t>(p1 - separator);
+    }
+
+    if(patLen==0 || (patLen==defaultPatLen && !u_strncmp(pattern, defaultPattern, patLen))) {
+        pattern=defaultPattern;
+        patLen=defaultPatLen;
+        sub0Pos=defaultSub0Pos;
+        sub1Pos=defaultSub1Pos;
+        // use default formatOpenParen etc. set above
+    } else { /* non-default pattern */
+        char16_t *p0=u_strstr(pattern, sub0);
+        char16_t *p1=u_strstr(pattern, sub1);
+        if (p0==nullptr || p1==nullptr) {
+            *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
+            return 0;
+        }
+        sub0Pos = static_cast<int32_t>(p0-pattern);
+        sub1Pos = static_cast<int32_t>(p1-pattern);
+        if (sub1Pos < sub0Pos) { /* a very odd pattern */
+            int32_t t=sub0Pos; sub0Pos=sub1Pos; sub1Pos=t;
+            langi=1;
+        }
+        if (u_strchr(pattern, 0xFF08) != nullptr) {
+            formatOpenParen         = 0xFF08; // fullwidth (
+            formatReplaceOpenParen  = 0xFF3B; // fullwidth [
+            formatCloseParen        = 0xFF09; // fullwidth )
+            formatReplaceCloseParen = 0xFF3D; // fullwidth ]
+        }
+    }
+
+    /* We loop here because there is one case in which after the first pass we could need to
+     * reextract the data.  If there's initial padding before the first element, we put in
+     * the padding and then write that element.  If it turns out there's no second element,
+     * we didn't need the padding.  If we do need the data (no preflight), and the first element
+     * would have fit but for the padding, we need to reextract.  In this case (only) we
+     * adjust the parameters so padding is not added, and repeat.
+     */
+    do {
+        char16_t* p=dest;
+        int32_t patPos=0; /* position in the pattern, used for non-substitution portions */
+        int32_t langLen=0; /* length of language substitution */
+        int32_t langPos=0; /* position in output of language substitution */
+        int32_t restLen=0; /* length of 'everything else' substitution */
+        int32_t restPos=0; /* position in output of 'everything else' substitution */
+        icu::LocalUEnumerationPointer kenum; /* keyword enumeration */
+
+        /* prefix of pattern, extremely likely to be empty */
+        if(sub0Pos) {
+            if(destCapacity >= sub0Pos) {
+                while (patPos < sub0Pos) {
+                    *p++ = pattern[patPos++];
+                }
+            } else {
+                patPos=sub0Pos;
+            }
+            length=sub0Pos;
+        } else {
+            length=0;
+        }
+
+        for(int32_t subi=0,resti=0;subi<2;) { /* iterate through patterns 0 and 1*/
+            UBool subdone = false; /* set true when ready to move to next substitution */
+
+            /* prep p and cap for calls to get display components, pin cap to 0 since
+               they complain if cap is negative */
+            int32_t cap=destCapacity-length;
+            if (cap <= 0) {
+                cap=0;
+            } else {
+                p=dest+length;
+            }
+
+            if (subi == langi) { /* {0}*/
+                if(haveLang) {
+                    langPos=length;
+                    langLen=uloc_getDisplayLanguage(locale, displayLocale, p, cap, pErrorCode);
+                    length+=langLen;
+                    haveLang=langLen>0;
+                }
+                subdone=true;
+            } else { /* {1} */
+                if(!haveRest) {
+                    subdone=true;
+                } else {
+                    int32_t len; /* length of component (plus other stuff) we just fetched */
+                    switch(resti++) {
+                        case 0:
+                            restPos=length;
+                            len=uloc_getDisplayScriptInContext(locale, displayLocale, p, cap, pErrorCode);
+                            break;
+                        case 1:
+                            len=uloc_getDisplayCountry(locale, displayLocale, p, cap, pErrorCode);
+                            break;
+                        case 2:
+                            len=uloc_getDisplayVariant(locale, displayLocale, p, cap, pErrorCode);
+                            break;
+                        case 3:
+                            kenum.adoptInstead(uloc_openKeywords(locale, pErrorCode));
+                            U_FALLTHROUGH;
+                        default: {
+                            const char* kw=uenum_next(kenum.getAlias(), &len, pErrorCode);
+                            if (kw == nullptr) {
+                                len=0; /* mark that we didn't add a component */
+                                subdone=true;
+                            } else {
+                                /* incorporating this behavior into the loop made it even more complex,
+                                   so just special case it here */
+                                len = uloc_getDisplayKeyword(kw, displayLocale, p, cap, pErrorCode);
+                                if(len) {
+                                    if(len < cap) {
+                                        p[len]=0x3d; /* '=', assume we'll need it */
+                                    }
+                                    len+=1;
+
+                                    /* adjust for call to get keyword */
+                                    cap-=len;
+                                    if(cap <= 0) {
+                                        cap=0;
+                                    } else {
+                                        p+=len;
+                                    }
+                                }
+                                /* reset for call below */
+                                if(*pErrorCode == U_BUFFER_OVERFLOW_ERROR) {
+                                    *pErrorCode=U_ZERO_ERROR;
+                                }
+                                int32_t vlen = uloc_getDisplayKeywordValue(locale, kw, displayLocale,
+                                                                           p, cap, pErrorCode);
+                                if(len) {
+                                    if(vlen==0) {
+                                        --len; /* remove unneeded '=' */
+                                    }
+                                    /* restore cap and p to what they were at start */
+                                    cap=destCapacity-length;
+                                    if(cap <= 0) {
+                                        cap=0;
+                                    } else {
+                                        p=dest+length;
+                                    }
+                                }
+                                len+=vlen; /* total we added for key + '=' + value */
+                            }
+                        } break;
+                    } /* end switch */
+
+                    if (len>0) {
+                        /* we added a component, so add separator and write it if there's room. */
+                        if(len+sepLen<=cap) {
+                            const char16_t * plimit = p + len;
+                            for (; p < plimit; p++) {
+                                if (*p == formatOpenParen) {
+                                    *p = formatReplaceOpenParen;
+                                } else if (*p == formatCloseParen) {
+                                    *p = formatReplaceCloseParen;
+                                }
+                            }
+                            for(int32_t i=0;i<sepLen;++i) {
+                                *p++=separator[i];
+                            }
+                        }
+                        length+=len+sepLen;
+                    } else if(subdone) {
+                        /* remove separator if we added it */
+                        if (length!=restPos) {
+                            length-=sepLen;
+                        }
+                        restLen=length-restPos;
+                        haveRest=restLen>0;
+                    }
+                }
+            }
+
+            if(*pErrorCode == U_BUFFER_OVERFLOW_ERROR) {
+                *pErrorCode=U_ZERO_ERROR;
+            }
+
+            if(subdone) {
+                if(haveLang && haveRest) {
+                    /* append internal portion of pattern, the first time,
+                       or last portion of pattern the second time */
+                    int32_t padLen;
+                    patPos+=subLen;
+                    padLen=(subi==0 ? sub1Pos : patLen)-patPos;
+                    if(length+padLen <= destCapacity) {
+                        p=dest+length;
+                        for(int32_t i=0;i<padLen;++i) {
+                            *p++=pattern[patPos++];
+                        }
+                    } else {
+                        patPos+=padLen;
+                    }
+                    length+=padLen;
+                } else if(subi==0) {
+                    /* don't have first component, reset for second component */
+                    sub0Pos=0;
+                    length=0;
+                } else if(length>0) {
+                    /* true length is the length of just the component we got. */
+                    length=haveLang?langLen:restLen;
+                    if(dest && sub0Pos!=0) {
+                        if (sub0Pos+length<=destCapacity) {
+                            /* first component not at start of result,
+                               but we have full component in buffer. */
+                            u_memmove(dest, dest+(haveLang?langPos:restPos), length);
+                        } else {
+                            /* would have fit, but didn't because of pattern prefix. */
+                            sub0Pos=0; /* stops initial padding (and a second retry,
+                                          so we won't end up here again) */
+                            retry=true;
+                        }
+                    }
+                }
+
+                ++subi; /* move on to next substitution */
+            }
+        }
+    } while(retry);
+
+    return u_terminateUChars(dest, destCapacity, length, pErrorCode);
+}
+
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayKeyword(const char* keyword,
+                       const char* displayLocale,
+                       char16_t* dest,
+                       int32_t destCapacity,
+                       UErrorCode* status){
+
+    /* argument checking */
+    if(status==nullptr || U_FAILURE(*status)) {
+        return 0;
+    }
+
+    if(destCapacity<0 || (destCapacity>0 && dest==nullptr)) {
+        *status=U_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+
+
+    /* pass itemKey=nullptr to look for a top-level item */
+    return _getStringOrCopyKey(U_ICUDATA_LANG, displayLocale,
+                               _kKeys, nullptr,
+                               keyword, 
+                               keyword,      
+                               dest, destCapacity,
+                               status);
+
+}
+
+
+#define UCURRENCY_DISPLAY_NAME_INDEX 1
+
+U_CAPI int32_t U_EXPORT2
+uloc_getDisplayKeywordValue(   const char* locale,
+                               const char* keyword,
+                               const char* displayLocale,
+                               char16_t* dest,
+                               int32_t destCapacity,
+                               UErrorCode* status){
+
+
+    /* argument checking */
+    if(status==nullptr || U_FAILURE(*status)) {
+        return 0;
+    }
+
+    if(destCapacity<0 || (destCapacity>0 && dest==nullptr)) {
+        *status=U_ILLEGAL_ARGUMENT_ERROR;
+        return 0;
+    }
+
+    /* get the keyword value */
+    CharString keywordValue;
+    {
+        CharStringByteSink sink(&keywordValue);
+        ulocimp_getKeywordValue(locale, keyword, sink, status);
+    }
+
+    /* 
+     * if the keyword is equal to currency .. then to get the display name 
+     * we need to do the fallback ourselves
+     */
+    if(uprv_stricmp(keyword, _kCurrency)==0){
+
+        int32_t dispNameLen = 0;
+        const char16_t *dispName = nullptr;
+
+        icu::LocalUResourceBundlePointer bundle(
+                ures_open(U_ICUDATA_CURR, displayLocale, status));
+        icu::LocalUResourceBundlePointer currencies(
+                ures_getByKey(bundle.getAlias(), _kCurrencies, nullptr, status));
+        icu::LocalUResourceBundlePointer currency(
+                ures_getByKeyWithFallback(currencies.getAlias(), keywordValue.data(), nullptr, status));
+
+        dispName = ures_getStringByIndex(currency.getAlias(), UCURRENCY_DISPLAY_NAME_INDEX, &dispNameLen, status);
+
+        if(U_FAILURE(*status)){
+            if(*status == U_MISSING_RESOURCE_ERROR){
+                /* we just want to write the value over if nothing is available */
+                *status = U_USING_DEFAULT_WARNING;
+            }else{
+                return 0;
+            }
+        }
+
+        /* now copy the dispName over if not nullptr */
+        if(dispName != nullptr){
+            if(dispNameLen <= destCapacity){
+                u_memcpy(dest, dispName, dispNameLen);
+                return u_terminateUChars(dest, destCapacity, dispNameLen, status);
+            }else{
+                *status = U_BUFFER_OVERFLOW_ERROR;
+                return dispNameLen;
+            }
+        }else{
+            /* we have not found the display name for the value .. just copy over */
+            if(keywordValue.length() <= destCapacity){
+                u_charsToUChars(keywordValue.data(), dest, keywordValue.length());
+                return u_terminateUChars(dest, destCapacity, keywordValue.length(), status);
+            }else{
+                 *status = U_BUFFER_OVERFLOW_ERROR;
+                return keywordValue.length();
+            }
+        }
+
+        
+    }else{
+
+        return _getStringOrCopyKey(U_ICUDATA_LANG, displayLocale,
+                                   _kTypes, keyword, 
+                                   keywordValue.data(),
+                                   keywordValue.data(),
+                                   dest, destCapacity,
+                                   status);
+    }
+}