// © 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 locid.cpp
*
* Created by: Richard Gillam
*
* Modification History:
*
*   Date        Name        Description
*   02/11/97    aliu        Changed gLocPath to fgDataDirectory and added
*                           methods to get and set it.
*   04/02/97    aliu        Made operator!= inline; fixed return value
*                           of getName().
*   04/15/97    aliu        Cleanup for AIX/Win32.
*   04/24/97    aliu        Numerous changes per code review.
*   08/18/98    stephen     Changed getDisplayName()
*                           Added SIMPLIFIED_CHINESE, TRADITIONAL_CHINESE
*                           Added getISOCountries(), getISOLanguages(),
*                           getLanguagesForCountry()
*   03/16/99    bertrand    rehaul.
*   07/21/99    stephen     Added U_CFUNC setDefault
*   11/09/99    weiv        Added const char * getName() const;
*   04/12/00    srl         removing unicodestring api's and cached hash code
*   08/10/01    grhoten     Change the static Locales to accessor functions
******************************************************************************
*/

#include <utility>

#include "unicode/bytestream.h"
#include "unicode/locid.h"
#include "unicode/strenum.h"
#include "unicode/stringpiece.h"
#include "unicode/uloc.h"
#include "putilimp.h"
#include "mutex.h"
#include "umutex.h"
#include "uassert.h"
#include "cmemory.h"
#include "cstring.h"
#include "uassert.h"
#include "uhash.h"
#include "ulocimp.h"
#include "ucln_cmn.h"
#include "ustr_imp.h"
#include "charstr.h"
#include "bytesinkutil.h"

U_CDECL_BEGIN
static UBool U_CALLCONV locale_cleanup(void);
U_CDECL_END

U_NAMESPACE_BEGIN

static Locale   *gLocaleCache = NULL;
static UInitOnce gLocaleCacheInitOnce = U_INITONCE_INITIALIZER;

// gDefaultLocaleMutex protects all access to gDefaultLocalesHashT and gDefaultLocale.
static UMutex gDefaultLocaleMutex = U_MUTEX_INITIALIZER;
static UHashtable *gDefaultLocalesHashT = NULL;
static Locale *gDefaultLocale = NULL;

/**
 * \def ULOC_STRING_LIMIT
 * strings beyond this value crash in CharString
 */
#define ULOC_STRING_LIMIT 357913941

U_NAMESPACE_END

typedef enum ELocalePos {
    eENGLISH,
    eFRENCH,
    eGERMAN,
    eITALIAN,
    eJAPANESE,
    eKOREAN,
    eCHINESE,

    eFRANCE,
    eGERMANY,
    eITALY,
    eJAPAN,
    eKOREA,
    eCHINA,      /* Alias for PRC */
    eTAIWAN,
    eUK,
    eUS,
    eCANADA,
    eCANADA_FRENCH,
    eROOT,


    //eDEFAULT,
    eMAX_LOCALES
} ELocalePos;

U_CFUNC int32_t locale_getKeywords(const char *localeID,
            char prev,
            char *keywords, int32_t keywordCapacity,
            char *values, int32_t valuesCapacity, int32_t *valLen,
            UBool valuesToo,
            UErrorCode *status);

U_CDECL_BEGIN
//
// Deleter function for Locales owned by the default Locale hash table/
//
static void U_CALLCONV
deleteLocale(void *obj) {
    delete (icu::Locale *) obj;
}

static UBool U_CALLCONV locale_cleanup(void)
{
    U_NAMESPACE_USE

    delete [] gLocaleCache;
    gLocaleCache = NULL;
    gLocaleCacheInitOnce.reset();

    if (gDefaultLocalesHashT) {
        uhash_close(gDefaultLocalesHashT);   // Automatically deletes all elements, using deleter func.
        gDefaultLocalesHashT = NULL;
    }
    gDefaultLocale = NULL;
    return TRUE;
}


static void U_CALLCONV locale_init(UErrorCode &status) {
    U_NAMESPACE_USE

    U_ASSERT(gLocaleCache == NULL);
    gLocaleCache = new Locale[(int)eMAX_LOCALES];
    if (gLocaleCache == NULL) {
        status = U_MEMORY_ALLOCATION_ERROR;
        return;
    }
    ucln_common_registerCleanup(UCLN_COMMON_LOCALE, locale_cleanup);
    gLocaleCache[eROOT]          = Locale("");
    gLocaleCache[eENGLISH]       = Locale("en");
    gLocaleCache[eFRENCH]        = Locale("fr");
    gLocaleCache[eGERMAN]        = Locale("de");
    gLocaleCache[eITALIAN]       = Locale("it");
    gLocaleCache[eJAPANESE]      = Locale("ja");
    gLocaleCache[eKOREAN]        = Locale("ko");
    gLocaleCache[eCHINESE]       = Locale("zh");
    gLocaleCache[eFRANCE]        = Locale("fr", "FR");
    gLocaleCache[eGERMANY]       = Locale("de", "DE");
    gLocaleCache[eITALY]         = Locale("it", "IT");
    gLocaleCache[eJAPAN]         = Locale("ja", "JP");
    gLocaleCache[eKOREA]         = Locale("ko", "KR");
    gLocaleCache[eCHINA]         = Locale("zh", "CN");
    gLocaleCache[eTAIWAN]        = Locale("zh", "TW");
    gLocaleCache[eUK]            = Locale("en", "GB");
    gLocaleCache[eUS]            = Locale("en", "US");
    gLocaleCache[eCANADA]        = Locale("en", "CA");
    gLocaleCache[eCANADA_FRENCH] = Locale("fr", "CA");
}

U_CDECL_END

U_NAMESPACE_BEGIN

Locale *locale_set_default_internal(const char *id, UErrorCode& status) {
    // Synchronize this entire function.
    Mutex lock(&gDefaultLocaleMutex);

    UBool canonicalize = FALSE;

    // If given a NULL string for the locale id, grab the default
    //   name from the system.
    //   (Different from most other locale APIs, where a null name means use
    //    the current ICU default locale.)
    if (id == NULL) {
        id = uprv_getDefaultLocaleID();   // This function not thread safe? TODO: verify.
        canonicalize = TRUE; // always canonicalize host ID
    }

    char localeNameBuf[512];

    if (canonicalize) {
        uloc_canonicalize(id, localeNameBuf, sizeof(localeNameBuf)-1, &status);
    } else {
        uloc_getName(id, localeNameBuf, sizeof(localeNameBuf)-1, &status);
    }
    localeNameBuf[sizeof(localeNameBuf)-1] = 0;  // Force null termination in event of
                                                 //   a long name filling the buffer.
                                                 //   (long names are truncated.)
                                                 //
    if (U_FAILURE(status)) {
        return gDefaultLocale;
    }

    if (gDefaultLocalesHashT == NULL) {
        gDefaultLocalesHashT = uhash_open(uhash_hashChars, uhash_compareChars, NULL, &status);
        if (U_FAILURE(status)) {
            return gDefaultLocale;
        }
        uhash_setValueDeleter(gDefaultLocalesHashT, deleteLocale);
        ucln_common_registerCleanup(UCLN_COMMON_LOCALE, locale_cleanup);
    }

    Locale *newDefault = (Locale *)uhash_get(gDefaultLocalesHashT, localeNameBuf);
    if (newDefault == NULL) {
        newDefault = new Locale(Locale::eBOGUS);
        if (newDefault == NULL) {
            status = U_MEMORY_ALLOCATION_ERROR;
            return gDefaultLocale;
        }
        newDefault->init(localeNameBuf, FALSE);
        uhash_put(gDefaultLocalesHashT, (char*) newDefault->getName(), newDefault, &status);
        if (U_FAILURE(status)) {
            return gDefaultLocale;
        }
    }
    gDefaultLocale = newDefault;
    return gDefaultLocale;
}

U_NAMESPACE_END

/* sfb 07/21/99 */
U_CFUNC void
locale_set_default(const char *id)
{
    U_NAMESPACE_USE
    UErrorCode status = U_ZERO_ERROR;
    locale_set_default_internal(id, status);
}
/* end */

U_CFUNC const char *
locale_get_default(void)
{
    U_NAMESPACE_USE
    return Locale::getDefault().getName();
}


U_NAMESPACE_BEGIN

UOBJECT_DEFINE_RTTI_IMPLEMENTATION(Locale)

/*Character separating the posix id fields*/
// '_'
// In the platform codepage.
#define SEP_CHAR '_'

Locale::~Locale()
{
    if (baseName != fullName) {
        uprv_free(baseName);
    }
    baseName = NULL;
    /*if fullName is on the heap, we free it*/
    if (fullName != fullNameBuffer)
    {
        uprv_free(fullName);
        fullName = NULL;
    }
}

Locale::Locale()
    : UObject(), fullName(fullNameBuffer), baseName(NULL)
{
    init(NULL, FALSE);
}

/*
 * Internal constructor to allow construction of a locale object with
 *   NO side effects.   (Default constructor tries to get
 *   the default locale.)
 */
Locale::Locale(Locale::ELocaleType)
    : UObject(), fullName(fullNameBuffer), baseName(NULL)
{
    setToBogus();
}


Locale::Locale( const   char * newLanguage,
                const   char * newCountry,
                const   char * newVariant,
                const   char * newKeywords)
    : UObject(), fullName(fullNameBuffer), baseName(NULL)
{
    if( (newLanguage==NULL) && (newCountry == NULL) && (newVariant == NULL) )
    {
        init(NULL, FALSE); /* shortcut */
    }
    else
    {
        UErrorCode status = U_ZERO_ERROR;
        int32_t size = 0;
        int32_t lsize = 0;
        int32_t csize = 0;
        int32_t vsize = 0;
        int32_t ksize = 0;

        // Calculate the size of the resulting string.

        // Language
        if ( newLanguage != NULL )
        {
            lsize = (int32_t)uprv_strlen(newLanguage);
            if ( lsize < 0 || lsize > ULOC_STRING_LIMIT ) { // int32 wrap
                setToBogus();
                return;
            }
            size = lsize;
        }

        CharString togo(newLanguage, lsize, status); // start with newLanguage

        // _Country
        if ( newCountry != NULL )
        {
            csize = (int32_t)uprv_strlen(newCountry);
            if ( csize < 0 || csize > ULOC_STRING_LIMIT ) { // int32 wrap
                setToBogus();
                return;
            }
            size += csize;
        }

        // _Variant
        if ( newVariant != NULL )
        {
            // remove leading _'s
            while(newVariant[0] == SEP_CHAR)
            {
                newVariant++;
            }

            // remove trailing _'s
            vsize = (int32_t)uprv_strlen(newVariant);
            if ( vsize < 0 || vsize > ULOC_STRING_LIMIT ) { // int32 wrap
                setToBogus();
                return;
            }
            while( (vsize>1) && (newVariant[vsize-1] == SEP_CHAR) )
            {
                vsize--;
            }
        }

        if( vsize > 0 )
        {
            size += vsize;
        }

        // Separator rules:
        if ( vsize > 0 )
        {
            size += 2;  // at least: __v
        }
        else if ( csize > 0 )
        {
            size += 1;  // at least: _v
        }

        if ( newKeywords != NULL)
        {
            ksize = (int32_t)uprv_strlen(newKeywords);
            if ( ksize < 0 || ksize > ULOC_STRING_LIMIT ) {
              setToBogus();
              return;
            }
            size += ksize + 1;
        }

        //  NOW we have the full locale string..
        // Now, copy it back.

        // newLanguage is already copied

        if ( ( vsize != 0 ) || (csize != 0) )  // at least:  __v
        {                                      //            ^
            togo.append(SEP_CHAR, status);
        }

        if ( csize != 0 )
        {
            togo.append(newCountry, status);
        }

        if ( vsize != 0)
        {
            togo.append(SEP_CHAR, status)
                .append(newVariant, vsize, status);
        }

        if ( ksize != 0)
        {
            if (uprv_strchr(newKeywords, '=')) {
                togo.append('@', status); /* keyword parsing */
            }
            else {
                togo.append('_', status); /* Variant parsing with a script */
                if ( vsize == 0) {
                    togo.append('_', status); /* No country found */
                }
            }
            togo.append(newKeywords, status);
        }

        if (U_FAILURE(status)) {
            // Something went wrong with appending, etc.
            setToBogus();
            return;
        }
        // Parse it, because for example 'language' might really be a complete
        // string.
        init(togo.data(), FALSE);
    }
}

Locale::Locale(const Locale &other)
    : UObject(other), fullName(fullNameBuffer), baseName(NULL)
{
    *this = other;
}

Locale::Locale(Locale&& other) U_NOEXCEPT
    : UObject(other), fullName(fullNameBuffer), baseName(fullName) {
  *this = std::move(other);
}

Locale& Locale::operator=(const Locale& other) {
    if (this == &other) {
        return *this;
    }

    setToBogus();

    if (other.fullName == other.fullNameBuffer) {
        uprv_strcpy(fullNameBuffer, other.fullNameBuffer);
    } else if (other.fullName == nullptr) {
        fullName = nullptr;
    } else {
        fullName = uprv_strdup(other.fullName);
        if (fullName == nullptr) return *this;
    }

    if (other.baseName == other.fullName) {
        baseName = fullName;
    } else if (other.baseName != nullptr) {
        baseName = uprv_strdup(other.baseName);
        if (baseName == nullptr) return *this;
    }

    uprv_strcpy(language, other.language);
    uprv_strcpy(script, other.script);
    uprv_strcpy(country, other.country);

    variantBegin = other.variantBegin;
    fIsBogus = other.fIsBogus;

    return *this;
}

Locale& Locale::operator=(Locale&& other) U_NOEXCEPT {
    if (baseName != fullName) uprv_free(baseName);
    if (fullName != fullNameBuffer) uprv_free(fullName);

    if (other.fullName == other.fullNameBuffer) {
        uprv_strcpy(fullNameBuffer, other.fullNameBuffer);
        fullName = fullNameBuffer;
    } else {
        fullName = other.fullName;
    }

    if (other.baseName == other.fullName) {
        baseName = fullName;
    } else {
        baseName = other.baseName;
    }

    uprv_strcpy(language, other.language);
    uprv_strcpy(script, other.script);
    uprv_strcpy(country, other.country);

    variantBegin = other.variantBegin;
    fIsBogus = other.fIsBogus;

    other.baseName = other.fullName = other.fullNameBuffer;

    return *this;
}

Locale *
Locale::clone() const {
    return new Locale(*this);
}

UBool
Locale::operator==( const   Locale& other) const
{
    return (uprv_strcmp(other.fullName, fullName) == 0);
}

#define ISASCIIALPHA(c) (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))

/*This function initializes a Locale from a C locale ID*/
Locale& Locale::init(const char* localeID, UBool canonicalize)
{
    fIsBogus = FALSE;
    /* Free our current storage */
    if (baseName != fullName) {
        uprv_free(baseName);
    }
    baseName = NULL;
    if(fullName != fullNameBuffer) {
        uprv_free(fullName);
        fullName = fullNameBuffer;
    }

    // not a loop:
    // just an easy way to have a common error-exit
    // without goto and without another function
    do {
        char *separator;
        char *field[5] = {0};
        int32_t fieldLen[5] = {0};
        int32_t fieldIdx;
        int32_t variantField;
        int32_t length;
        UErrorCode err;

        if(localeID == NULL) {
            // not an error, just set the default locale
            return *this = getDefault();
        }

        /* preset all fields to empty */
        language[0] = script[0] = country[0] = 0;

        // "canonicalize" the locale ID to ICU/Java format
        err = U_ZERO_ERROR;
        length = canonicalize ?
            uloc_canonicalize(localeID, fullName, sizeof(fullNameBuffer), &err) :
            uloc_getName(localeID, fullName, sizeof(fullNameBuffer), &err);

        if(err == U_BUFFER_OVERFLOW_ERROR || length >= (int32_t)sizeof(fullNameBuffer)) {
            /*Go to heap for the fullName if necessary*/
            fullName = (char *)uprv_malloc(sizeof(char)*(length + 1));
            if(fullName == 0) {
                fullName = fullNameBuffer;
                break; // error: out of memory
            }
            err = U_ZERO_ERROR;
            length = canonicalize ?
                uloc_canonicalize(localeID, fullName, length+1, &err) :
                uloc_getName(localeID, fullName, length+1, &err);
        }
        if(U_FAILURE(err) || err == U_STRING_NOT_TERMINATED_WARNING) {
            /* should never occur */
            break;
        }

        variantBegin = length;

        /* after uloc_getName/canonicalize() we know that only '_' are separators */
        separator = field[0] = fullName;
        fieldIdx = 1;
        while ((separator = uprv_strchr(field[fieldIdx-1], SEP_CHAR)) != 0 && fieldIdx < UPRV_LENGTHOF(field)-1) {
            field[fieldIdx] = separator + 1;
            fieldLen[fieldIdx-1] = (int32_t)(separator - field[fieldIdx-1]);
            fieldIdx++;
        }
        // variant may contain @foo or .foo POSIX cruft; remove it
        separator = uprv_strchr(field[fieldIdx-1], '@');
        char* sep2 = uprv_strchr(field[fieldIdx-1], '.');
        if (separator!=NULL || sep2!=NULL) {
            if (separator==NULL || (sep2!=NULL && separator > sep2)) {
                separator = sep2;
            }
            fieldLen[fieldIdx-1] = (int32_t)(separator - field[fieldIdx-1]);
        } else {
            fieldLen[fieldIdx-1] = length - (int32_t)(field[fieldIdx-1] - fullName);
        }

        if (fieldLen[0] >= (int32_t)(sizeof(language)))
        {
            break; // error: the language field is too long
        }

        variantField = 1; /* Usually the 2nd one, except when a script or country is also used. */
        if (fieldLen[0] > 0) {
            /* We have a language */
            uprv_memcpy(language, fullName, fieldLen[0]);
            language[fieldLen[0]] = 0;
        }
        if (fieldLen[1] == 4 && ISASCIIALPHA(field[1][0]) &&
                ISASCIIALPHA(field[1][1]) && ISASCIIALPHA(field[1][2]) &&
                ISASCIIALPHA(field[1][3])) {
            /* We have at least a script */
            uprv_memcpy(script, field[1], fieldLen[1]);
            script[fieldLen[1]] = 0;
            variantField++;
        }

        if (fieldLen[variantField] == 2 || fieldLen[variantField] == 3) {
            /* We have a country */
            uprv_memcpy(country, field[variantField], fieldLen[variantField]);
            country[fieldLen[variantField]] = 0;
            variantField++;
        } else if (fieldLen[variantField] == 0) {
            variantField++; /* script or country empty but variant in next field (i.e. en__POSIX) */
        }

        if (fieldLen[variantField] > 0) {
            /* We have a variant */
            variantBegin = (int32_t)(field[variantField] - fullName);
        }

        err = U_ZERO_ERROR;
        initBaseName(err);
        if (U_FAILURE(err)) {
            break;
        }

        // successful end of init()
        return *this;
    } while(0); /*loop doesn't iterate*/

    // when an error occurs, then set this object to "bogus" (there is no UErrorCode here)
    setToBogus();

    return *this;
}

/*
 * Set up the base name.
 * If there are no key words, it's exactly the full name.
 * If key words exist, it's the full name truncated at the '@' character.
 * Need to set up both at init() and after setting a keyword.
 */
void
Locale::initBaseName(UErrorCode &status) {
    if (U_FAILURE(status)) {
        return;
    }
    U_ASSERT(baseName==NULL || baseName==fullName);
    const char *atPtr = uprv_strchr(fullName, '@');
    const char *eqPtr = uprv_strchr(fullName, '=');
    if (atPtr && eqPtr && atPtr < eqPtr) {
        // Key words exist.
        int32_t baseNameLength = (int32_t)(atPtr - fullName);
        baseName = (char *)uprv_malloc(baseNameLength + 1);
        if (baseName == NULL) {
            status = U_MEMORY_ALLOCATION_ERROR;
            return;
        }
        uprv_strncpy(baseName, fullName, baseNameLength);
        baseName[baseNameLength] = 0;

        // The original computation of variantBegin leaves it equal to the length
        // of fullName if there is no variant.  It should instead be
        // the length of the baseName.
        if (variantBegin > baseNameLength) {
            variantBegin = baseNameLength;
        }
    } else {
        baseName = fullName;
    }
}


int32_t
Locale::hashCode() const
{
    return ustr_hashCharsN(fullName, static_cast<int32_t>(uprv_strlen(fullName)));
}

void
Locale::setToBogus() {
    /* Free our current storage */
    if(baseName != fullName) {
        uprv_free(baseName);
    }
    baseName = NULL;
    if(fullName != fullNameBuffer) {
        uprv_free(fullName);
        fullName = fullNameBuffer;
    }
    *fullNameBuffer = 0;
    *language = 0;
    *script = 0;
    *country = 0;
    fIsBogus = TRUE;
    variantBegin = 0;
}

const Locale& U_EXPORT2
Locale::getDefault()
{
    {
        Mutex lock(&gDefaultLocaleMutex);
        if (gDefaultLocale != NULL) {
            return *gDefaultLocale;
        }
    }
    UErrorCode status = U_ZERO_ERROR;
    return *locale_set_default_internal(NULL, status);
}


void U_EXPORT2
Locale::setDefault( const   Locale&     newLocale,
                            UErrorCode&  status)
{
    if (U_FAILURE(status)) {
        return;
    }

    /* Set the default from the full name string of the supplied locale.
     * This is a convenient way to access the default locale caching mechanisms.
     */
    const char *localeID = newLocale.getName();
    locale_set_default_internal(localeID, status);
}

void
Locale::addLikelySubtags(UErrorCode& status) {
    if (U_FAILURE(status)) {
        return;
    }

    // The maximized locale ID string is often longer, but there is no good
    // heuristic to estimate just how much longer. Leave that to CharString.
    CharString maximizedLocaleID;
    int32_t maximizedLocaleIDCapacity = static_cast<int32_t>(uprv_strlen(fullName));

    char* buffer;
    int32_t reslen;

    for (;;) {
        buffer = maximizedLocaleID.getAppendBuffer(
                /*minCapacity=*/maximizedLocaleIDCapacity,
                /*desiredCapacityHint=*/maximizedLocaleIDCapacity,
                maximizedLocaleIDCapacity,
                status);

        if (U_FAILURE(status)) {
            return;
        }

        reslen = uloc_addLikelySubtags(
                fullName,
                buffer,
                maximizedLocaleIDCapacity,
                &status);

        if (status != U_BUFFER_OVERFLOW_ERROR) {
            break;
        }

        maximizedLocaleIDCapacity = reslen;
        status = U_ZERO_ERROR;
    }

    if (U_FAILURE(status)) {
        return;
    }

    maximizedLocaleID.append(buffer, reslen, status);
    if (status == U_STRING_NOT_TERMINATED_WARNING) {
        status = U_ZERO_ERROR;  // Terminators provided by CharString.
    }

    if (U_FAILURE(status)) {
        return;
    }

    init(maximizedLocaleID.data(), /*canonicalize=*/FALSE);
    if (isBogus()) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
    }
}

void
Locale::minimizeSubtags(UErrorCode& status) {
    if (U_FAILURE(status)) {
        return;
    }

    // Except for a few edge cases (like the empty string, that is minimized to
    // "en__POSIX"), minimized locale ID strings will be either the same length
    // or shorter than their input.
    CharString minimizedLocaleID;
    int32_t minimizedLocaleIDCapacity = static_cast<int32_t>(uprv_strlen(fullName));

    char* buffer;
    int32_t reslen;

    for (;;) {
        buffer = minimizedLocaleID.getAppendBuffer(
                /*minCapacity=*/minimizedLocaleIDCapacity,
                /*desiredCapacityHint=*/minimizedLocaleIDCapacity,
                minimizedLocaleIDCapacity,
                status);

        if (U_FAILURE(status)) {
            return;
        }

        reslen = uloc_minimizeSubtags(
                fullName,
                buffer,
                minimizedLocaleIDCapacity,
                &status);

        if (status != U_BUFFER_OVERFLOW_ERROR) {
            break;
        }

        // Because of the internal minimal buffer size of CharString, I can't
        // think of any input data for which this could possibly ever happen.
        // Maybe it would be better replaced with an assertion instead?
        minimizedLocaleIDCapacity = reslen;
        status = U_ZERO_ERROR;
    }

    if (U_FAILURE(status)) {
        return;
    }

    minimizedLocaleID.append(buffer, reslen, status);
    if (status == U_STRING_NOT_TERMINATED_WARNING) {
        status = U_ZERO_ERROR;  // Terminators provided by CharString.
    }

    if (U_FAILURE(status)) {
        return;
    }

    init(minimizedLocaleID.data(), /*canonicalize=*/FALSE);
    if (isBogus()) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
    }
}

Locale U_EXPORT2
Locale::forLanguageTag(StringPiece tag, UErrorCode& status)
{
    Locale result(Locale::eBOGUS);

    if (U_FAILURE(status)) {
        return result;
    }

    // If a BCP-47 language tag is passed as the language parameter to the
    // normal Locale constructor, it will actually fall back to invoking
    // uloc_forLanguageTag() to parse it if it somehow is able to detect that
    // the string actually is BCP-47. This works well for things like strings
    // using BCP-47 extensions, but it does not at all work for things like
    // BCP-47 grandfathered tags (eg. "en-GB-oed") which are possible to also
    // interpret as ICU locale IDs and because of that won't trigger the BCP-47
    // parsing. Therefore the code here explicitly calls uloc_forLanguageTag()
    // and then Locale::init(), instead of just calling the normal constructor.

    // All simple language tags will have the exact same length as ICU locale
    // ID strings as they have as BCP-47 strings (like "en_US" for "en-US").
    CharString localeID;
    int32_t resultCapacity = tag.size();

    char* buffer;
    int32_t parsedLength, reslen;

    for (;;) {
        buffer = localeID.getAppendBuffer(
                /*minCapacity=*/resultCapacity,
                /*desiredCapacityHint=*/resultCapacity,
                resultCapacity,
                status);

        if (U_FAILURE(status)) {
            return result;
        }

        reslen = ulocimp_forLanguageTag(
                tag.data(),
                tag.length(),
                buffer,
                resultCapacity,
                &parsedLength,
                &status);

        if (status != U_BUFFER_OVERFLOW_ERROR) {
            break;
        }

        // For all BCP-47 language tags that use extensions, the corresponding
        // ICU locale ID will be longer but uloc_forLanguageTag() does compute
        // the exact length needed so this memory reallocation will be done at
        // most once.
        resultCapacity = reslen;
        status = U_ZERO_ERROR;
    }

    if (U_FAILURE(status)) {
        return result;
    }

    if (parsedLength != tag.size()) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return result;
    }

    localeID.append(buffer, reslen, status);
    if (status == U_STRING_NOT_TERMINATED_WARNING) {
        status = U_ZERO_ERROR;  // Terminators provided by CharString.
    }

    if (U_FAILURE(status)) {
        return result;
    }

    result.init(localeID.data(), /*canonicalize=*/FALSE);
    if (result.isBogus()) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
    }
    return result;
}

void
Locale::toLanguageTag(ByteSink& sink, UErrorCode& status) const
{
    if (U_FAILURE(status)) {
        return;
    }

    if (fIsBogus) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    // All simple language tags will have the exact same length as BCP-47
    // strings as they have as ICU locale IDs (like "en-US" for "en_US").
    LocalMemory<char> scratch;
    int32_t scratch_capacity = static_cast<int32_t>(uprv_strlen(fullName));

    if (scratch_capacity == 0) {
        scratch_capacity = 3;  // "und"
    }

    char* buffer;
    int32_t result_capacity, reslen;

    for (;;) {
        if (scratch.allocateInsteadAndReset(scratch_capacity) == nullptr) {
            status = U_MEMORY_ALLOCATION_ERROR;
            return;
        }

        buffer = sink.GetAppendBuffer(
                /*min_capacity=*/scratch_capacity,
                /*desired_capacity_hint=*/scratch_capacity,
                scratch.getAlias(),
                scratch_capacity,
                &result_capacity);

        reslen = uloc_toLanguageTag(
                fullName,
                buffer,
                result_capacity,
                /*strict=*/FALSE,
                &status);

        if (status != U_BUFFER_OVERFLOW_ERROR) {
            break;
        }

        // For some very few edge cases a language tag will be longer as a
        // BCP-47 string than it is as an ICU locale ID. Most notoriously "C"
        // expands to the BCP-47 tag "en-US-u-va-posix", 16 times longer, and
        // it'll take several calls to uloc_toLanguageTag() to figure that out.
        // https://unicode-org.atlassian.net/browse/ICU-20132
        scratch_capacity = reslen;
        status = U_ZERO_ERROR;
    }

    if (U_FAILURE(status)) {
        return;
    }

    sink.Append(buffer, reslen);
    if (status == U_STRING_NOT_TERMINATED_WARNING) {
        status = U_ZERO_ERROR;  // Terminators not used.
    }
}

Locale U_EXPORT2
Locale::createFromName (const char *name)
{
    if (name) {
        Locale l("");
        l.init(name, FALSE);
        return l;
    }
    else {
        return getDefault();
    }
}

Locale U_EXPORT2
Locale::createCanonical(const char* name) {
    Locale loc("");
    loc.init(name, TRUE);
    return loc;
}

const char *
Locale::getISO3Language() const
{
    return uloc_getISO3Language(fullName);
}


const char *
Locale::getISO3Country() const
{
    return uloc_getISO3Country(fullName);
}

/**
 * Return the LCID value as specified in the "LocaleID" resource for this
 * locale.  The LocaleID must be expressed as a hexadecimal number, from
 * one to four digits.  If the LocaleID resource is not present, or is
 * in an incorrect format, 0 is returned.  The LocaleID is for use in
 * Windows (it is an LCID), but is available on all platforms.
 */
uint32_t
Locale::getLCID() const
{
    return uloc_getLCID(fullName);
}

const char* const* U_EXPORT2 Locale::getISOCountries()
{
    return uloc_getISOCountries();
}

const char* const* U_EXPORT2 Locale::getISOLanguages()
{
    return uloc_getISOLanguages();
}

// Set the locale's data based on a posix id.
void Locale::setFromPOSIXID(const char *posixID)
{
    init(posixID, TRUE);
}

const Locale & U_EXPORT2
Locale::getRoot(void)
{
    return getLocale(eROOT);
}

const Locale & U_EXPORT2
Locale::getEnglish(void)
{
    return getLocale(eENGLISH);
}

const Locale & U_EXPORT2
Locale::getFrench(void)
{
    return getLocale(eFRENCH);
}

const Locale & U_EXPORT2
Locale::getGerman(void)
{
    return getLocale(eGERMAN);
}

const Locale & U_EXPORT2
Locale::getItalian(void)
{
    return getLocale(eITALIAN);
}

const Locale & U_EXPORT2
Locale::getJapanese(void)
{
    return getLocale(eJAPANESE);
}

const Locale & U_EXPORT2
Locale::getKorean(void)
{
    return getLocale(eKOREAN);
}

const Locale & U_EXPORT2
Locale::getChinese(void)
{
    return getLocale(eCHINESE);
}

const Locale & U_EXPORT2
Locale::getSimplifiedChinese(void)
{
    return getLocale(eCHINA);
}

const Locale & U_EXPORT2
Locale::getTraditionalChinese(void)
{
    return getLocale(eTAIWAN);
}


const Locale & U_EXPORT2
Locale::getFrance(void)
{
    return getLocale(eFRANCE);
}

const Locale & U_EXPORT2
Locale::getGermany(void)
{
    return getLocale(eGERMANY);
}

const Locale & U_EXPORT2
Locale::getItaly(void)
{
    return getLocale(eITALY);
}

const Locale & U_EXPORT2
Locale::getJapan(void)
{
    return getLocale(eJAPAN);
}

const Locale & U_EXPORT2
Locale::getKorea(void)
{
    return getLocale(eKOREA);
}

const Locale & U_EXPORT2
Locale::getChina(void)
{
    return getLocale(eCHINA);
}

const Locale & U_EXPORT2
Locale::getPRC(void)
{
    return getLocale(eCHINA);
}

const Locale & U_EXPORT2
Locale::getTaiwan(void)
{
    return getLocale(eTAIWAN);
}

const Locale & U_EXPORT2
Locale::getUK(void)
{
    return getLocale(eUK);
}

const Locale & U_EXPORT2
Locale::getUS(void)
{
    return getLocale(eUS);
}

const Locale & U_EXPORT2
Locale::getCanada(void)
{
    return getLocale(eCANADA);
}

const Locale & U_EXPORT2
Locale::getCanadaFrench(void)
{
    return getLocale(eCANADA_FRENCH);
}

const Locale &
Locale::getLocale(int locid)
{
    Locale *localeCache = getLocaleCache();
    U_ASSERT((locid < eMAX_LOCALES)&&(locid>=0));
    if (localeCache == NULL) {
        // Failure allocating the locale cache.
        //   The best we can do is return a NULL reference.
        locid = 0;
    }
    return localeCache[locid]; /*operating on NULL*/
}

/*
This function is defined this way in order to get around static
initialization and static destruction.
 */
Locale *
Locale::getLocaleCache(void)
{
    UErrorCode status = U_ZERO_ERROR;
    umtx_initOnce(gLocaleCacheInitOnce, locale_init, status);
    return gLocaleCache;
}

class KeywordEnumeration : public StringEnumeration {
private:
    char *keywords;
    char *current;
    int32_t length;
    UnicodeString currUSKey;
    static const char fgClassID;/* Warning this is used beyond the typical RTTI usage. */

public:
    static UClassID U_EXPORT2 getStaticClassID(void) { return (UClassID)&fgClassID; }
    virtual UClassID getDynamicClassID(void) const { return getStaticClassID(); }
public:
    KeywordEnumeration(const char *keys, int32_t keywordLen, int32_t currentIndex, UErrorCode &status)
        : keywords((char *)&fgClassID), current((char *)&fgClassID), length(0) {
        if(U_SUCCESS(status) && keywordLen != 0) {
            if(keys == NULL || keywordLen < 0) {
                status = U_ILLEGAL_ARGUMENT_ERROR;
            } else {
                keywords = (char *)uprv_malloc(keywordLen+1);
                if (keywords == NULL) {
                    status = U_MEMORY_ALLOCATION_ERROR;
                }
                else {
                    uprv_memcpy(keywords, keys, keywordLen);
                    keywords[keywordLen] = 0;
                    current = keywords + currentIndex;
                    length = keywordLen;
                }
            }
        }
    }

    virtual ~KeywordEnumeration();

    virtual StringEnumeration * clone() const
    {
        UErrorCode status = U_ZERO_ERROR;
        return new KeywordEnumeration(keywords, length, (int32_t)(current - keywords), status);
    }

    virtual int32_t count(UErrorCode &/*status*/) const {
        char *kw = keywords;
        int32_t result = 0;
        while(*kw) {
            result++;
            kw += uprv_strlen(kw)+1;
        }
        return result;
    }

    virtual const char* next(int32_t* resultLength, UErrorCode& status) {
        const char* result;
        int32_t len;
        if(U_SUCCESS(status) && *current != 0) {
            result = current;
            len = (int32_t)uprv_strlen(current);
            current += len+1;
            if(resultLength != NULL) {
                *resultLength = len;
            }
        } else {
            if(resultLength != NULL) {
                *resultLength = 0;
            }
            result = NULL;
        }
        return result;
    }

    virtual const UnicodeString* snext(UErrorCode& status) {
        int32_t resultLength = 0;
        const char *s = next(&resultLength, status);
        return setChars(s, resultLength, status);
    }

    virtual void reset(UErrorCode& /*status*/) {
        current = keywords;
    }
};

const char KeywordEnumeration::fgClassID = '\0';

KeywordEnumeration::~KeywordEnumeration() {
    uprv_free(keywords);
}

// A wrapper around KeywordEnumeration that calls uloc_toUnicodeLocaleKey() in
// the next() method for each keyword before returning it.
class UnicodeKeywordEnumeration : public KeywordEnumeration {
public:
    using KeywordEnumeration::KeywordEnumeration;
    virtual ~UnicodeKeywordEnumeration();

    virtual const char* next(int32_t* resultLength, UErrorCode& status) {
        const char* legacy_key = KeywordEnumeration::next(nullptr, status);
        if (U_SUCCESS(status) && legacy_key != nullptr) {
            const char* key = uloc_toUnicodeLocaleKey(legacy_key);
            if (key == nullptr) {
                status = U_ILLEGAL_ARGUMENT_ERROR;
            } else {
                if (resultLength != nullptr) {
                    *resultLength = static_cast<int32_t>(uprv_strlen(key));
                }
                return key;
            }
        }
        if (resultLength != nullptr) *resultLength = 0;
        return nullptr;
    }
};

// Out-of-line virtual destructor to serve as the "key function".
UnicodeKeywordEnumeration::~UnicodeKeywordEnumeration() = default;

StringEnumeration *
Locale::createKeywords(UErrorCode &status) const
{
    char keywords[256];
    int32_t keywordCapacity = sizeof keywords;
    StringEnumeration *result = NULL;

    if (U_FAILURE(status)) {
        return result;
    }

    const char* variantStart = uprv_strchr(fullName, '@');
    const char* assignment = uprv_strchr(fullName, '=');
    if(variantStart) {
        if(assignment > variantStart) {
            int32_t keyLen = locale_getKeywords(variantStart+1, '@', keywords, keywordCapacity, NULL, 0, NULL, FALSE, &status);
            if(U_SUCCESS(status) && keyLen) {
                result = new KeywordEnumeration(keywords, keyLen, 0, status);
                if (!result) {
                    status = U_MEMORY_ALLOCATION_ERROR;
                }
            }
        } else {
            status = U_INVALID_FORMAT_ERROR;
        }
    }
    return result;
}

StringEnumeration *
Locale::createUnicodeKeywords(UErrorCode &status) const
{
    char keywords[256];
    int32_t keywordCapacity = sizeof keywords;
    StringEnumeration *result = NULL;

    if (U_FAILURE(status)) {
        return result;
    }

    const char* variantStart = uprv_strchr(fullName, '@');
    const char* assignment = uprv_strchr(fullName, '=');
    if(variantStart) {
        if(assignment > variantStart) {
            int32_t keyLen = locale_getKeywords(variantStart+1, '@', keywords, keywordCapacity, NULL, 0, NULL, FALSE, &status);
            if(U_SUCCESS(status) && keyLen) {
                result = new UnicodeKeywordEnumeration(keywords, keyLen, 0, status);
                if (!result) {
                    status = U_MEMORY_ALLOCATION_ERROR;
                }
            }
        } else {
            status = U_INVALID_FORMAT_ERROR;
        }
    }
    return result;
}

int32_t
Locale::getKeywordValue(const char* keywordName, char *buffer, int32_t bufLen, UErrorCode &status) const
{
    return uloc_getKeywordValue(fullName, keywordName, buffer, bufLen, &status);
}

void
Locale::getKeywordValue(StringPiece keywordName, ByteSink& sink, UErrorCode& status) const {
    if (U_FAILURE(status)) {
        return;
    }

    if (fIsBogus) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    // TODO: Remove the need for a const char* to a NUL terminated buffer.
    const CharString keywordName_nul(keywordName, status);
    if (U_FAILURE(status)) {
        return;
    }

    LocalMemory<char> scratch;
    int32_t scratch_capacity = 16;  // Arbitrarily chosen default size.

    char* buffer;
    int32_t result_capacity, reslen;

    for (;;) {
        if (scratch.allocateInsteadAndReset(scratch_capacity) == nullptr) {
            status = U_MEMORY_ALLOCATION_ERROR;
            return;
        }

        buffer = sink.GetAppendBuffer(
                /*min_capacity=*/scratch_capacity,
                /*desired_capacity_hint=*/scratch_capacity,
                scratch.getAlias(),
                scratch_capacity,
                &result_capacity);

        reslen = uloc_getKeywordValue(
                fullName,
                keywordName_nul.data(),
                buffer,
                result_capacity,
                &status);

        if (status != U_BUFFER_OVERFLOW_ERROR) {
            break;
        }

        scratch_capacity = reslen;
        status = U_ZERO_ERROR;
    }

    if (U_FAILURE(status)) {
        return;
    }

    sink.Append(buffer, reslen);
    if (status == U_STRING_NOT_TERMINATED_WARNING) {
        status = U_ZERO_ERROR;  // Terminators not used.
    }
}

void
Locale::getUnicodeKeywordValue(StringPiece keywordName,
                               ByteSink& sink,
                               UErrorCode& status) const {
    // TODO: Remove the need for a const char* to a NUL terminated buffer.
    const CharString keywordName_nul(keywordName, status);
    if (U_FAILURE(status)) {
        return;
    }

    const char* legacy_key = uloc_toLegacyKey(keywordName_nul.data());

    if (legacy_key == nullptr) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    CharString legacy_value;
    {
        CharStringByteSink sink(&legacy_value);
        getKeywordValue(legacy_key, sink, status);
    }

    if (U_FAILURE(status)) {
        return;
    }

    const char* unicode_value = uloc_toUnicodeLocaleType(
            keywordName_nul.data(), legacy_value.data());

    if (unicode_value == nullptr) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    sink.Append(unicode_value, static_cast<int32_t>(uprv_strlen(unicode_value)));
}

void
Locale::setKeywordValue(const char* keywordName, const char* keywordValue, UErrorCode &status)
{
    uloc_setKeywordValue(keywordName, keywordValue, fullName, ULOC_FULLNAME_CAPACITY, &status);
    if (U_SUCCESS(status) && baseName == fullName) {
        // May have added the first keyword, meaning that the fullName is no longer also the baseName.
        initBaseName(status);
    }
}

void
Locale::setKeywordValue(StringPiece keywordName,
                        StringPiece keywordValue,
                        UErrorCode& status) {
    // TODO: Remove the need for a const char* to a NUL terminated buffer.
    const CharString keywordName_nul(keywordName, status);
    const CharString keywordValue_nul(keywordValue, status);
    setKeywordValue(keywordName_nul.data(), keywordValue_nul.data(), status);
}

void
Locale::setUnicodeKeywordValue(StringPiece keywordName,
                               StringPiece keywordValue,
                               UErrorCode& status) {
    // TODO: Remove the need for a const char* to a NUL terminated buffer.
    const CharString keywordName_nul(keywordName, status);
    const CharString keywordValue_nul(keywordValue, status);

    if (U_FAILURE(status)) {
        return;
    }

    const char* legacy_key = uloc_toLegacyKey(keywordName_nul.data());

    if (legacy_key == nullptr) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    const char* legacy_value =
        uloc_toLegacyType(keywordName_nul.data(), keywordValue_nul.data());

    if (legacy_value == nullptr) {
        status = U_ILLEGAL_ARGUMENT_ERROR;
        return;
    }

    setKeywordValue(legacy_key, legacy_value, status);
}

const char *
Locale::getBaseName() const {
    return baseName;
}

//eof
U_NAMESPACE_END