virtualx-engine/thirdparty/icu4c/common/localematcher.cpp
2024-05-14 12:38:52 +03:00

834 lines
31 KiB
C++

// © 2019 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
// localematcher.cpp
// created: 2019may08 Markus W. Scherer
#include <optional>
#include "unicode/utypes.h"
#include "unicode/localebuilder.h"
#include "unicode/localematcher.h"
#include "unicode/locid.h"
#include "unicode/stringpiece.h"
#include "unicode/uloc.h"
#include "unicode/uobject.h"
#include "cstring.h"
#include "localeprioritylist.h"
#include "loclikelysubtags.h"
#include "locdistance.h"
#include "lsr.h"
#include "uassert.h"
#include "uhash.h"
#include "ustr_imp.h"
#include "uvector.h"
#define UND_LSR LSR("und", "", "", LSR::EXPLICIT_LSR)
/**
* Indicator for the lifetime of desired-locale objects passed into the LocaleMatcher.
*
* @draft ICU 65
*/
enum ULocMatchLifetime {
/**
* Locale objects are temporary.
* The matcher will make a copy of a locale that will be used beyond one function call.
*
* @draft ICU 65
*/
ULOCMATCH_TEMPORARY_LOCALES,
/**
* Locale objects are stored at least as long as the matcher is used.
* The matcher will keep only a pointer to a locale that will be used beyond one function call,
* avoiding a copy.
*
* @draft ICU 65
*/
ULOCMATCH_STORED_LOCALES // TODO: permanent? cached? clone?
};
#ifndef U_IN_DOXYGEN
typedef enum ULocMatchLifetime ULocMatchLifetime;
#endif
U_NAMESPACE_BEGIN
LocaleMatcher::Result::Result(LocaleMatcher::Result &&src) noexcept :
desiredLocale(src.desiredLocale),
supportedLocale(src.supportedLocale),
desiredIndex(src.desiredIndex),
supportedIndex(src.supportedIndex),
desiredIsOwned(src.desiredIsOwned) {
if (desiredIsOwned) {
src.desiredLocale = nullptr;
src.desiredIndex = -1;
src.desiredIsOwned = false;
}
}
LocaleMatcher::Result::~Result() {
if (desiredIsOwned) {
delete desiredLocale;
}
}
LocaleMatcher::Result &LocaleMatcher::Result::operator=(LocaleMatcher::Result &&src) noexcept {
this->~Result();
desiredLocale = src.desiredLocale;
supportedLocale = src.supportedLocale;
desiredIndex = src.desiredIndex;
supportedIndex = src.supportedIndex;
desiredIsOwned = src.desiredIsOwned;
if (desiredIsOwned) {
src.desiredLocale = nullptr;
src.desiredIndex = -1;
src.desiredIsOwned = false;
}
return *this;
}
Locale LocaleMatcher::Result::makeResolvedLocale(UErrorCode &errorCode) const {
if (U_FAILURE(errorCode) || supportedLocale == nullptr) {
return Locale::getRoot();
}
const Locale *bestDesired = getDesiredLocale();
if (bestDesired == nullptr || *supportedLocale == *bestDesired) {
return *supportedLocale;
}
LocaleBuilder b;
b.setLocale(*supportedLocale);
// Copy the region from bestDesired, if there is one.
const char *region = bestDesired->getCountry();
if (*region != 0) {
b.setRegion(region);
}
// Copy the variants from bestDesired, if there are any.
// Note that this will override any supportedLocale variants.
// For example, "sco-ulster-fonipa" + "...-fonupa" => "sco-fonupa" (replacing ulster).
const char *variants = bestDesired->getVariant();
if (*variants != 0) {
b.setVariant(variants);
}
// Copy the extensions from bestDesired, if there are any.
// C++ note: The following note, copied from Java, may not be true,
// as long as C++ copies by legacy ICU keyword, not by extension singleton.
// Note that this will override any supportedLocale extensions.
// For example, "th-u-nu-latn-ca-buddhist" + "...-u-nu-native" => "th-u-nu-native"
// (replacing calendar).
b.copyExtensionsFrom(*bestDesired, errorCode);
return b.build(errorCode);
}
LocaleMatcher::Builder::Builder(LocaleMatcher::Builder &&src) noexcept :
errorCode_(src.errorCode_),
supportedLocales_(src.supportedLocales_),
thresholdDistance_(src.thresholdDistance_),
demotion_(src.demotion_),
defaultLocale_(src.defaultLocale_),
withDefault_(src.withDefault_),
favor_(src.favor_),
direction_(src.direction_) {
src.supportedLocales_ = nullptr;
src.defaultLocale_ = nullptr;
}
LocaleMatcher::Builder::~Builder() {
delete supportedLocales_;
delete defaultLocale_;
delete maxDistanceDesired_;
delete maxDistanceSupported_;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::operator=(LocaleMatcher::Builder &&src) noexcept {
this->~Builder();
errorCode_ = src.errorCode_;
supportedLocales_ = src.supportedLocales_;
thresholdDistance_ = src.thresholdDistance_;
demotion_ = src.demotion_;
defaultLocale_ = src.defaultLocale_;
withDefault_ = src.withDefault_,
favor_ = src.favor_;
direction_ = src.direction_;
src.supportedLocales_ = nullptr;
src.defaultLocale_ = nullptr;
return *this;
}
void LocaleMatcher::Builder::clearSupportedLocales() {
if (supportedLocales_ != nullptr) {
supportedLocales_->removeAllElements();
}
}
bool LocaleMatcher::Builder::ensureSupportedLocaleVector() {
if (U_FAILURE(errorCode_)) { return false; }
if (supportedLocales_ != nullptr) { return true; }
LocalPointer<UVector> lpSupportedLocales(new UVector(uprv_deleteUObject, nullptr, errorCode_), errorCode_);
if (U_FAILURE(errorCode_)) { return false; }
supportedLocales_ = lpSupportedLocales.orphan();
return true;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setSupportedLocalesFromListString(
StringPiece locales) {
LocalePriorityList list(locales, errorCode_);
if (U_FAILURE(errorCode_)) { return *this; }
clearSupportedLocales();
if (!ensureSupportedLocaleVector()) { return *this; }
int32_t length = list.getLengthIncludingRemoved();
for (int32_t i = 0; i < length; ++i) {
Locale *locale = list.orphanLocaleAt(i);
if (locale == nullptr) { continue; }
supportedLocales_->adoptElement(locale, errorCode_);
if (U_FAILURE(errorCode_)) {
break;
}
}
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setSupportedLocales(Locale::Iterator &locales) {
if (ensureSupportedLocaleVector()) {
clearSupportedLocales();
while (locales.hasNext() && U_SUCCESS(errorCode_)) {
const Locale &locale = locales.next();
LocalPointer<Locale> clone (locale.clone(), errorCode_);
supportedLocales_->adoptElement(clone.orphan(), errorCode_);
}
}
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::addSupportedLocale(const Locale &locale) {
if (ensureSupportedLocaleVector()) {
LocalPointer<Locale> clone(locale.clone(), errorCode_);
supportedLocales_->adoptElement(clone.orphan(), errorCode_);
}
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setNoDefaultLocale() {
if (U_FAILURE(errorCode_)) { return *this; }
delete defaultLocale_;
defaultLocale_ = nullptr;
withDefault_ = false;
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setDefaultLocale(const Locale *defaultLocale) {
if (U_FAILURE(errorCode_)) { return *this; }
Locale *clone = nullptr;
if (defaultLocale != nullptr) {
clone = defaultLocale->clone();
if (clone == nullptr) {
errorCode_ = U_MEMORY_ALLOCATION_ERROR;
return *this;
}
}
delete defaultLocale_;
defaultLocale_ = clone;
withDefault_ = true;
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setFavorSubtag(ULocMatchFavorSubtag subtag) {
if (U_FAILURE(errorCode_)) { return *this; }
favor_ = subtag;
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setDemotionPerDesiredLocale(ULocMatchDemotion demotion) {
if (U_FAILURE(errorCode_)) { return *this; }
demotion_ = demotion;
return *this;
}
LocaleMatcher::Builder &LocaleMatcher::Builder::setMaxDistance(const Locale &desired,
const Locale &supported) {
if (U_FAILURE(errorCode_)) { return *this; }
Locale *desiredClone = desired.clone();
Locale *supportedClone = supported.clone();
if (desiredClone == nullptr || supportedClone == nullptr) {
delete desiredClone; // in case only one could not be allocated
delete supportedClone;
errorCode_ = U_MEMORY_ALLOCATION_ERROR;
return *this;
}
delete maxDistanceDesired_;
delete maxDistanceSupported_;
maxDistanceDesired_ = desiredClone;
maxDistanceSupported_ = supportedClone;
return *this;
}
#if 0
/**
* <i>Internal only!</i>
*
* @param thresholdDistance the thresholdDistance to set, with -1 = default
* @return this Builder object
* @internal
* @deprecated This API is ICU internal only.
*/
@Deprecated
LocaleMatcher::Builder &LocaleMatcher::Builder::internalSetThresholdDistance(int32_t thresholdDistance) {
if (U_FAILURE(errorCode_)) { return *this; }
if (thresholdDistance > 100) {
thresholdDistance = 100;
}
thresholdDistance_ = thresholdDistance;
return *this;
}
#endif
UBool LocaleMatcher::Builder::copyErrorTo(UErrorCode &outErrorCode) const {
if (U_FAILURE(outErrorCode)) { return true; }
if (U_SUCCESS(errorCode_)) { return false; }
outErrorCode = errorCode_;
return true;
}
LocaleMatcher LocaleMatcher::Builder::build(UErrorCode &errorCode) const {
if (U_SUCCESS(errorCode) && U_FAILURE(errorCode_)) {
errorCode = errorCode_;
}
return LocaleMatcher(*this, errorCode);
}
namespace {
LSR getMaximalLsrOrUnd(const LikelySubtags &likelySubtags, const Locale &locale,
UErrorCode &errorCode) {
if (U_FAILURE(errorCode) || locale.isBogus() || *locale.getName() == 0 /* "und" */) {
return UND_LSR;
} else {
return likelySubtags.makeMaximizedLsrFrom(locale, false, errorCode);
}
}
int32_t hashLSR(const UHashTok token) {
const LSR *lsr = static_cast<const LSR *>(token.pointer);
return lsr->hashCode;
}
UBool compareLSRs(const UHashTok t1, const UHashTok t2) {
const LSR *lsr1 = static_cast<const LSR *>(t1.pointer);
const LSR *lsr2 = static_cast<const LSR *>(t2.pointer);
return *lsr1 == *lsr2;
}
} // namespace
int32_t LocaleMatcher::putIfAbsent(const LSR &lsr, int32_t i, int32_t suppLength,
UErrorCode &errorCode) {
if (U_FAILURE(errorCode)) { return suppLength; }
if (!uhash_containsKey(supportedLsrToIndex, &lsr)) {
uhash_putiAllowZero(supportedLsrToIndex, const_cast<LSR *>(&lsr), i, &errorCode);
if (U_SUCCESS(errorCode)) {
supportedLSRs[suppLength] = &lsr;
supportedIndexes[suppLength++] = i;
}
}
return suppLength;
}
LocaleMatcher::LocaleMatcher(const Builder &builder, UErrorCode &errorCode) :
likelySubtags(*LikelySubtags::getSingleton(errorCode)),
localeDistance(*LocaleDistance::getSingleton(errorCode)),
thresholdDistance(builder.thresholdDistance_),
demotionPerDesiredLocale(0),
favorSubtag(builder.favor_),
direction(builder.direction_),
supportedLocales(nullptr), lsrs(nullptr), supportedLocalesLength(0),
supportedLsrToIndex(nullptr),
supportedLSRs(nullptr), supportedIndexes(nullptr), supportedLSRsLength(0),
ownedDefaultLocale(nullptr), defaultLocale(nullptr) {
if (U_FAILURE(errorCode)) { return; }
const Locale *def = builder.defaultLocale_;
LSR builderDefaultLSR;
const LSR *defLSR = nullptr;
if (def != nullptr) {
ownedDefaultLocale = def->clone();
if (ownedDefaultLocale == nullptr) {
errorCode = U_MEMORY_ALLOCATION_ERROR;
return;
}
def = ownedDefaultLocale;
builderDefaultLSR = getMaximalLsrOrUnd(likelySubtags, *def, errorCode);
if (U_FAILURE(errorCode)) { return; }
defLSR = &builderDefaultLSR;
}
supportedLocalesLength = builder.supportedLocales_ != nullptr ?
builder.supportedLocales_->size() : 0;
if (supportedLocalesLength > 0) {
// Store the supported locales in input order,
// so that when different types are used (e.g., language tag strings)
// we can return those by parallel index.
supportedLocales = static_cast<const Locale **>(
uprv_malloc(supportedLocalesLength * sizeof(const Locale *)));
// Supported LRSs in input order.
// In C++, we store these permanently to simplify ownership management
// in the hash tables. Duplicate LSRs (if any) are unused overhead.
lsrs = new LSR[supportedLocalesLength];
if (supportedLocales == nullptr || lsrs == nullptr) {
errorCode = U_MEMORY_ALLOCATION_ERROR;
return;
}
// If the constructor fails partway, we need null pointers for destructibility.
uprv_memset(supportedLocales, 0, supportedLocalesLength * sizeof(const Locale *));
for (int32_t i = 0; i < supportedLocalesLength; ++i) {
const Locale &locale = *static_cast<Locale *>(builder.supportedLocales_->elementAt(i));
supportedLocales[i] = locale.clone();
if (supportedLocales[i] == nullptr) {
errorCode = U_MEMORY_ALLOCATION_ERROR;
return;
}
const Locale &supportedLocale = *supportedLocales[i];
LSR &lsr = lsrs[i] = getMaximalLsrOrUnd(likelySubtags, supportedLocale, errorCode);
lsr.setHashCode();
if (U_FAILURE(errorCode)) { return; }
}
// We need an unordered map from LSR to first supported locale with that LSR,
// and an ordered list of (LSR, supported index) for
// the supported locales in the following order:
// 1. Default locale, if it is supported.
// 2. Priority locales (aka "paradigm locales") in builder order.
// 3. Remaining locales in builder order.
supportedLsrToIndex = uhash_openSize(hashLSR, compareLSRs, uhash_compareLong,
supportedLocalesLength, &errorCode);
if (U_FAILURE(errorCode)) { return; }
supportedLSRs = static_cast<const LSR **>(
uprv_malloc(supportedLocalesLength * sizeof(const LSR *)));
supportedIndexes = static_cast<int32_t *>(
uprv_malloc(supportedLocalesLength * sizeof(int32_t)));
if (supportedLSRs == nullptr || supportedIndexes == nullptr) {
errorCode = U_MEMORY_ALLOCATION_ERROR;
return;
}
int32_t suppLength = 0;
// Determine insertion order.
// Add locales immediately that are equivalent to the default.
MaybeStackArray<int8_t, 100> order(supportedLocalesLength, errorCode);
if (U_FAILURE(errorCode)) { return; }
int32_t numParadigms = 0;
for (int32_t i = 0; i < supportedLocalesLength; ++i) {
const Locale &locale = *supportedLocales[i];
const LSR &lsr = lsrs[i];
if (defLSR == nullptr && builder.withDefault_) {
// Implicit default locale = first supported locale, if not turned off.
U_ASSERT(i == 0);
def = &locale;
defLSR = &lsr;
order[i] = 1;
suppLength = putIfAbsent(lsr, 0, suppLength, errorCode);
} else if (defLSR != nullptr && lsr.isEquivalentTo(*defLSR)) {
order[i] = 1;
suppLength = putIfAbsent(lsr, i, suppLength, errorCode);
} else if (localeDistance.isParadigmLSR(lsr)) {
order[i] = 2;
++numParadigms;
} else {
order[i] = 3;
}
if (U_FAILURE(errorCode)) { return; }
}
// Add supported paradigm locales.
int32_t paradigmLimit = suppLength + numParadigms;
for (int32_t i = 0; i < supportedLocalesLength && suppLength < paradigmLimit; ++i) {
if (order[i] == 2) {
suppLength = putIfAbsent(lsrs[i], i, suppLength, errorCode);
}
}
// Add remaining supported locales.
for (int32_t i = 0; i < supportedLocalesLength; ++i) {
if (order[i] == 3) {
suppLength = putIfAbsent(lsrs[i], i, suppLength, errorCode);
}
}
supportedLSRsLength = suppLength;
// If supportedLSRsLength < supportedLocalesLength then
// we waste as many array slots as there are duplicate supported LSRs,
// but the amount of wasted space is small as long as there are few duplicates.
}
defaultLocale = def;
if (builder.demotion_ == ULOCMATCH_DEMOTION_REGION) {
demotionPerDesiredLocale = localeDistance.getDefaultDemotionPerDesiredLocale();
}
if (thresholdDistance >= 0) {
// already copied
} else if (builder.maxDistanceDesired_ != nullptr) {
LSR suppLSR = getMaximalLsrOrUnd(likelySubtags, *builder.maxDistanceSupported_, errorCode);
const LSR *pSuppLSR = &suppLSR;
int32_t indexAndDistance = localeDistance.getBestIndexAndDistance(
getMaximalLsrOrUnd(likelySubtags, *builder.maxDistanceDesired_, errorCode),
&pSuppLSR, 1,
LocaleDistance::shiftDistance(100), favorSubtag, direction);
if (U_SUCCESS(errorCode)) {
// +1 for an exclusive threshold from an inclusive max.
thresholdDistance = LocaleDistance::getDistanceFloor(indexAndDistance) + 1;
} else {
thresholdDistance = 0;
}
} else {
thresholdDistance = localeDistance.getDefaultScriptDistance();
}
}
LocaleMatcher::LocaleMatcher(LocaleMatcher &&src) noexcept :
likelySubtags(src.likelySubtags),
localeDistance(src.localeDistance),
thresholdDistance(src.thresholdDistance),
demotionPerDesiredLocale(src.demotionPerDesiredLocale),
favorSubtag(src.favorSubtag),
direction(src.direction),
supportedLocales(src.supportedLocales), lsrs(src.lsrs),
supportedLocalesLength(src.supportedLocalesLength),
supportedLsrToIndex(src.supportedLsrToIndex),
supportedLSRs(src.supportedLSRs),
supportedIndexes(src.supportedIndexes),
supportedLSRsLength(src.supportedLSRsLength),
ownedDefaultLocale(src.ownedDefaultLocale), defaultLocale(src.defaultLocale) {
src.supportedLocales = nullptr;
src.lsrs = nullptr;
src.supportedLocalesLength = 0;
src.supportedLsrToIndex = nullptr;
src.supportedLSRs = nullptr;
src.supportedIndexes = nullptr;
src.supportedLSRsLength = 0;
src.ownedDefaultLocale = nullptr;
src.defaultLocale = nullptr;
}
LocaleMatcher::~LocaleMatcher() {
for (int32_t i = 0; i < supportedLocalesLength; ++i) {
delete supportedLocales[i];
}
uprv_free(supportedLocales);
delete[] lsrs;
uhash_close(supportedLsrToIndex);
uprv_free(supportedLSRs);
uprv_free(supportedIndexes);
delete ownedDefaultLocale;
}
LocaleMatcher &LocaleMatcher::operator=(LocaleMatcher &&src) noexcept {
this->~LocaleMatcher();
thresholdDistance = src.thresholdDistance;
demotionPerDesiredLocale = src.demotionPerDesiredLocale;
favorSubtag = src.favorSubtag;
direction = src.direction;
supportedLocales = src.supportedLocales;
lsrs = src.lsrs;
supportedLocalesLength = src.supportedLocalesLength;
supportedLsrToIndex = src.supportedLsrToIndex;
supportedLSRs = src.supportedLSRs;
supportedIndexes = src.supportedIndexes;
supportedLSRsLength = src.supportedLSRsLength;
ownedDefaultLocale = src.ownedDefaultLocale;
defaultLocale = src.defaultLocale;
src.supportedLocales = nullptr;
src.lsrs = nullptr;
src.supportedLocalesLength = 0;
src.supportedLsrToIndex = nullptr;
src.supportedLSRs = nullptr;
src.supportedIndexes = nullptr;
src.supportedLSRsLength = 0;
src.ownedDefaultLocale = nullptr;
src.defaultLocale = nullptr;
return *this;
}
class LocaleLsrIterator {
public:
LocaleLsrIterator(const LikelySubtags &likelySubtags, Locale::Iterator &locales,
ULocMatchLifetime lifetime) :
likelySubtags(likelySubtags), locales(locales), lifetime(lifetime) {}
~LocaleLsrIterator() {
if (lifetime == ULOCMATCH_TEMPORARY_LOCALES) {
delete remembered;
}
}
bool hasNext() const {
return locales.hasNext();
}
LSR next(UErrorCode &errorCode) {
current = &locales.next();
return getMaximalLsrOrUnd(likelySubtags, *current, errorCode);
}
void rememberCurrent(int32_t desiredIndex, UErrorCode &errorCode) {
if (U_FAILURE(errorCode)) { return; }
bestDesiredIndex = desiredIndex;
if (lifetime == ULOCMATCH_STORED_LOCALES) {
remembered = current;
} else {
// ULOCMATCH_TEMPORARY_LOCALES
delete remembered;
remembered = new Locale(*current);
if (remembered == nullptr) {
errorCode = U_MEMORY_ALLOCATION_ERROR;
}
}
}
const Locale *orphanRemembered() {
const Locale *rem = remembered;
remembered = nullptr;
return rem;
}
int32_t getBestDesiredIndex() const {
return bestDesiredIndex;
}
private:
const LikelySubtags &likelySubtags;
Locale::Iterator &locales;
ULocMatchLifetime lifetime;
const Locale *current = nullptr, *remembered = nullptr;
int32_t bestDesiredIndex = -1;
};
const Locale *LocaleMatcher::getBestMatch(const Locale &desiredLocale, UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) { return nullptr; }
std::optional<int32_t> suppIndex = getBestSuppIndex(
getMaximalLsrOrUnd(likelySubtags, desiredLocale, errorCode),
nullptr, errorCode);
return U_SUCCESS(errorCode) && suppIndex.has_value() ? supportedLocales[*suppIndex]
: defaultLocale;
}
const Locale *LocaleMatcher::getBestMatch(Locale::Iterator &desiredLocales,
UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) { return nullptr; }
if (!desiredLocales.hasNext()) {
return defaultLocale;
}
LocaleLsrIterator lsrIter(likelySubtags, desiredLocales, ULOCMATCH_TEMPORARY_LOCALES);
std::optional<int32_t> suppIndex = getBestSuppIndex(lsrIter.next(errorCode), &lsrIter, errorCode);
return U_SUCCESS(errorCode) && suppIndex.has_value() ? supportedLocales[*suppIndex]
: defaultLocale;
}
const Locale *LocaleMatcher::getBestMatchForListString(
StringPiece desiredLocaleList, UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) { return nullptr; }
LocalePriorityList list(desiredLocaleList, errorCode);
LocalePriorityList::Iterator iter = list.iterator();
return getBestMatch(iter, errorCode);
}
LocaleMatcher::Result LocaleMatcher::getBestMatchResult(
const Locale &desiredLocale, UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) {
return Result(nullptr, defaultLocale, -1, -1, false);
}
std::optional<int32_t> suppIndex = getBestSuppIndex(
getMaximalLsrOrUnd(likelySubtags, desiredLocale, errorCode),
nullptr, errorCode);
if (U_FAILURE(errorCode) || !suppIndex.has_value()) {
return Result(nullptr, defaultLocale, -1, -1, false);
} else {
return Result(&desiredLocale, supportedLocales[*suppIndex], 0, *suppIndex, false);
}
}
LocaleMatcher::Result LocaleMatcher::getBestMatchResult(
Locale::Iterator &desiredLocales, UErrorCode &errorCode) const {
if (U_FAILURE(errorCode) || !desiredLocales.hasNext()) {
return Result(nullptr, defaultLocale, -1, -1, false);
}
LocaleLsrIterator lsrIter(likelySubtags, desiredLocales, ULOCMATCH_TEMPORARY_LOCALES);
std::optional<int32_t> suppIndex = getBestSuppIndex(lsrIter.next(errorCode), &lsrIter, errorCode);
if (U_FAILURE(errorCode) || !suppIndex.has_value()) {
return Result(nullptr, defaultLocale, -1, -1, false);
} else {
return Result(lsrIter.orphanRemembered(), supportedLocales[*suppIndex],
lsrIter.getBestDesiredIndex(), *suppIndex, true);
}
}
std::optional<int32_t> LocaleMatcher::getBestSuppIndex(LSR desiredLSR,
LocaleLsrIterator *remainingIter,
UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) { return std::nullopt; }
int32_t desiredIndex = 0;
int32_t bestSupportedLsrIndex = -1;
for (int32_t bestShiftedDistance = LocaleDistance::shiftDistance(thresholdDistance);;) {
// Quick check for exact maximized LSR.
if (supportedLsrToIndex != nullptr) {
desiredLSR.setHashCode();
UBool found = false;
int32_t suppIndex = uhash_getiAndFound(supportedLsrToIndex, &desiredLSR, &found);
if (found) {
if (remainingIter != nullptr) {
remainingIter->rememberCurrent(desiredIndex, errorCode);
}
return suppIndex;
}
}
int32_t bestIndexAndDistance = localeDistance.getBestIndexAndDistance(
desiredLSR, supportedLSRs, supportedLSRsLength,
bestShiftedDistance, favorSubtag, direction);
if (bestIndexAndDistance >= 0) {
bestShiftedDistance = LocaleDistance::getShiftedDistance(bestIndexAndDistance);
if (remainingIter != nullptr) {
remainingIter->rememberCurrent(desiredIndex, errorCode);
if (U_FAILURE(errorCode)) { return std::nullopt; }
}
bestSupportedLsrIndex = LocaleDistance::getIndex(bestIndexAndDistance);
}
if ((bestShiftedDistance -= LocaleDistance::shiftDistance(demotionPerDesiredLocale)) <= 0) {
break;
}
if (remainingIter == nullptr || !remainingIter->hasNext()) {
break;
}
desiredLSR = remainingIter->next(errorCode);
if (U_FAILURE(errorCode)) { return std::nullopt; }
++desiredIndex;
}
if (bestSupportedLsrIndex < 0) {
// no good match
return std::nullopt;
}
return supportedIndexes[bestSupportedLsrIndex];
}
UBool LocaleMatcher::isMatch(const Locale &desired, const Locale &supported,
UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) { return false; }
LSR suppLSR = getMaximalLsrOrUnd(likelySubtags, supported, errorCode);
if (U_FAILURE(errorCode)) { return false; }
const LSR *pSuppLSR = &suppLSR;
int32_t indexAndDistance = localeDistance.getBestIndexAndDistance(
getMaximalLsrOrUnd(likelySubtags, desired, errorCode),
&pSuppLSR, 1,
LocaleDistance::shiftDistance(thresholdDistance), favorSubtag, direction);
return indexAndDistance >= 0;
}
double LocaleMatcher::internalMatch(const Locale &desired, const Locale &supported, UErrorCode &errorCode) const {
if (U_FAILURE(errorCode)) { return 0.; }
// Returns the inverse of the distance: That is, 1-distance(desired, supported).
LSR suppLSR = getMaximalLsrOrUnd(likelySubtags, supported, errorCode);
if (U_FAILURE(errorCode)) { return 0.; }
const LSR *pSuppLSR = &suppLSR;
int32_t indexAndDistance = localeDistance.getBestIndexAndDistance(
getMaximalLsrOrUnd(likelySubtags, desired, errorCode),
&pSuppLSR, 1,
LocaleDistance::shiftDistance(thresholdDistance), favorSubtag, direction);
double distance = LocaleDistance::getDistanceDouble(indexAndDistance);
return (100.0 - distance) / 100.0;
}
U_NAMESPACE_END
// uloc_acceptLanguage() --------------------------------------------------- ***
U_NAMESPACE_USE
namespace {
class LocaleFromTag {
public:
LocaleFromTag() : locale(Locale::getRoot()) {}
const Locale &operator()(const char *tag) { return locale = Locale(tag); }
private:
// Store the locale in the converter, rather than return a reference to a temporary,
// or a value which could go out of scope with the caller's reference to it.
Locale locale;
};
int32_t acceptLanguage(UEnumeration &supportedLocales, Locale::Iterator &desiredLocales,
char *dest, int32_t capacity, UAcceptResult *acceptResult,
UErrorCode &errorCode) {
if (U_FAILURE(errorCode)) { return 0; }
LocaleMatcher::Builder builder;
const char *locString;
while ((locString = uenum_next(&supportedLocales, nullptr, &errorCode)) != nullptr) {
Locale loc(locString);
if (loc.isBogus()) {
errorCode = U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
builder.addSupportedLocale(loc);
}
LocaleMatcher matcher = builder.build(errorCode);
LocaleMatcher::Result result = matcher.getBestMatchResult(desiredLocales, errorCode);
if (U_FAILURE(errorCode)) { return 0; }
if (result.getDesiredIndex() >= 0) {
if (acceptResult != nullptr) {
*acceptResult = *result.getDesiredLocale() == *result.getSupportedLocale() ?
ULOC_ACCEPT_VALID : ULOC_ACCEPT_FALLBACK;
}
const char *bestStr = result.getSupportedLocale()->getName();
int32_t bestLength = (int32_t)uprv_strlen(bestStr);
if (bestLength <= capacity) {
uprv_memcpy(dest, bestStr, bestLength);
}
return u_terminateChars(dest, capacity, bestLength, &errorCode);
} else {
if (acceptResult != nullptr) {
*acceptResult = ULOC_ACCEPT_FAILED;
}
return u_terminateChars(dest, capacity, 0, &errorCode);
}
}
} // namespace
U_CAPI int32_t U_EXPORT2
uloc_acceptLanguage(char *result, int32_t resultAvailable,
UAcceptResult *outResult,
const char **acceptList, int32_t acceptListCount,
UEnumeration *availableLocales,
UErrorCode *status) {
if (U_FAILURE(*status)) { return 0; }
if ((result == nullptr ? resultAvailable != 0 : resultAvailable < 0) ||
(acceptList == nullptr ? acceptListCount != 0 : acceptListCount < 0) ||
availableLocales == nullptr) {
*status = U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
LocaleFromTag converter;
Locale::ConvertingIterator<const char **, LocaleFromTag> desiredLocales(
acceptList, acceptList + acceptListCount, converter);
return acceptLanguage(*availableLocales, desiredLocales,
result, resultAvailable, outResult, *status);
}
U_CAPI int32_t U_EXPORT2
uloc_acceptLanguageFromHTTP(char *result, int32_t resultAvailable,
UAcceptResult *outResult,
const char *httpAcceptLanguage,
UEnumeration *availableLocales,
UErrorCode *status) {
if (U_FAILURE(*status)) { return 0; }
if ((result == nullptr ? resultAvailable != 0 : resultAvailable < 0) ||
httpAcceptLanguage == nullptr || availableLocales == nullptr) {
*status = U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
LocalePriorityList list(httpAcceptLanguage, *status);
LocalePriorityList::Iterator desiredLocales = list.iterator();
return acceptLanguage(*availableLocales, desiredLocales,
result, resultAvailable, outResult, *status);
}