ydb/contrib/libs/icu/io/uprntf_p.cpp

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
******************************************************************************
*
*   Copyright (C) 1998-2016, International Business Machines
*   Corporation and others.  All Rights Reserved.
*
******************************************************************************
*
* File uprntf_p.c
*
* Modification History:
*
*   Date        Name        Description
*   11/23/98    stephen     Creation.
*   03/12/99    stephen     Modified for new C API.
*   08/07/2003  george      Reunify printf implementations
******************************************************************************
*/

#include "unicode/utypes.h"

#if !UCONFIG_NO_FORMATTING && !UCONFIG_NO_CONVERSION

#include "unicode/ustring.h"
#include "unicode/utf16.h"
#include "uprintf.h"
#include "ufmt_cmn.h"
#include "cmemory.h"
#include "putilimp.h"

/* ANSI style formatting */
/* Use US-ASCII characters only for formatting */

/* % */
#define UFMT_SIMPLE_PERCENT {ufmt_simple_percent, u_printf_simple_percent_handler}
/* s */
#define UFMT_STRING         {ufmt_string, u_printf_string_handler}
/* c */
#define UFMT_CHAR           {ufmt_char, u_printf_char_handler}
/* d, i */
#define UFMT_INT            {ufmt_int, u_printf_integer_handler}
/* u */
#define UFMT_UINT           {ufmt_int, u_printf_uinteger_handler}
/* o */
#define UFMT_OCTAL          {ufmt_int, u_printf_octal_handler}
/* x, X */
#define UFMT_HEX            {ufmt_int, u_printf_hex_handler}
/* f */
#define UFMT_DOUBLE         {ufmt_double, u_printf_double_handler}
/* e, E */
#define UFMT_SCIENTIFIC     {ufmt_double, u_printf_scientific_handler}
/* g, G */
#define UFMT_SCIDBL         {ufmt_double, u_printf_scidbl_handler}
/* n */
#define UFMT_COUNT          {ufmt_count, u_printf_count_handler}

/* non-ANSI extensions */
/* Use US-ASCII characters only for formatting */

/* p */
#define UFMT_POINTER        {ufmt_pointer, u_printf_pointer_handler}
/* V */
#define UFMT_SPELLOUT       {ufmt_double, u_printf_spellout_handler}
/* P */
#define UFMT_PERCENT        {ufmt_double, u_printf_percent_handler}
/* C  K is old format */
#define UFMT_UCHAR          {ufmt_uchar, u_printf_uchar_handler}
/* S  U is old format */
#define UFMT_USTRING        {ufmt_ustring, u_printf_ustring_handler}


#define UFMT_EMPTY {ufmt_empty, nullptr}

/**
 * A u_printf handler function.  
 * A u_printf handler is responsible for handling a single u_printf 
 * format specification, for example 'd' or 's'.
 * @param stream The UFILE to which to write output.
 * @param info A pointer to a <TT>u_printf_spec_info</TT> struct containing
 * information on the format specification.
 * @param args A pointer to the argument data
 * @return The number of Unicode characters written to <TT>stream</TT>.
 */
typedef int32_t U_EXPORT2
u_printf_handler(const u_printf_stream_handler  *handler,

                 void                           *context,
                 ULocaleBundle                  *formatBundle,
                 const u_printf_spec_info       *info,
                 const ufmt_args                *args);

typedef struct u_printf_info {
    ufmt_type_info info;
    u_printf_handler *handler;
} u_printf_info;

/**
 * Struct encapsulating a single uprintf format specification.
 */
typedef struct u_printf_spec {
  u_printf_spec_info    fInfo;        /* Information on this spec */
  int32_t        fWidthPos;     /* Position of width in arg list */
  int32_t        fPrecisionPos;    /* Position of precision in arg list */
  int32_t        fArgPos;    /* Position of data in arg list */
} u_printf_spec;

#define UPRINTF_NUM_FMT_HANDLERS 108

/* We do not use handlers for 0-0x1f */
#define UPRINTF_BASE_FMT_HANDLERS 0x20

/* buffer size for formatting */
#define UPRINTF_BUFFER_SIZE 1024
#define UPRINTF_SYMBOL_BUFFER_SIZE 8

static const char16_t gNullStr[] = {0x28, 0x6E, 0x75, 0x6C, 0x6C, 0x29, 0}; /* "(null)" */
static const char16_t gSpaceStr[] = {0x20, 0}; /* " " */

/* Sets the sign of a format based on u_printf_spec_info */
/* TODO: Is setting the prefix symbol to a positive sign a good idea in all locales? */
static void
u_printf_set_sign(UNumberFormat        *format,
                   const u_printf_spec_info     *info,
                   char16_t *prefixBuffer,
                   int32_t *prefixBufLen,
                   UErrorCode *status)
{
    if(info->fShowSign) {
        *prefixBufLen = unum_getTextAttribute(format,
                                              UNUM_POSITIVE_PREFIX,
                                              prefixBuffer,
                                              *prefixBufLen,
                                              status);
        if (info->fSpace) {
            /* Setting UNUM_PLUS_SIGN_SYMBOL affects the exponent too. */
            /* unum_setSymbol(format, UNUM_PLUS_SIGN_SYMBOL, gSpaceStr, 1, &status); */
            unum_setTextAttribute(format, UNUM_POSITIVE_PREFIX, gSpaceStr, 1, status);
        }
        else {
            char16_t plusSymbol[UPRINTF_SYMBOL_BUFFER_SIZE];
            int32_t symbolLen;

            symbolLen = unum_getSymbol(format,
                UNUM_PLUS_SIGN_SYMBOL,
                plusSymbol,
                UPRV_LENGTHOF(plusSymbol),
                status);
            unum_setTextAttribute(format,
                UNUM_POSITIVE_PREFIX,
                plusSymbol,
                symbolLen,
                status);
        }
    }
    else {
        *prefixBufLen = 0;
    }
}

static void
u_printf_reset_sign(UNumberFormat        *format,
                   const u_printf_spec_info     *info,
                   char16_t *prefixBuffer,
                   int32_t *prefixBufLen,
                   UErrorCode *status)
{
    if(info->fShowSign) {
        unum_setTextAttribute(format,
                              UNUM_POSITIVE_PREFIX,
                              prefixBuffer,
                              *prefixBufLen,
                              status);
    }
}


/* handle a '%' */
static int32_t
u_printf_simple_percent_handler(const u_printf_stream_handler  *handler,
                                void                           *context,
                                ULocaleBundle                  *formatBundle,
                                const u_printf_spec_info       *info,
                                const ufmt_args                *args)
{
    (void)formatBundle;
    (void)info;
    (void)args;
    static const char16_t PERCENT[] = { UP_PERCENT };

    /* put a single '%' onto the output */
    return handler->write(context, PERCENT, 1);
}

/* handle 's' */
static int32_t
u_printf_string_handler(const u_printf_stream_handler  *handler,
                        void                           *context,
                        ULocaleBundle                  *formatBundle,
                        const u_printf_spec_info       *info,
                        const ufmt_args                *args)
{
    (void)formatBundle;
    char16_t *s;
    char16_t buffer[UFMT_DEFAULT_BUFFER_SIZE];
    int32_t len, written;
    int32_t argSize;
    const char* arg = static_cast<const char*>(args[0].ptrValue);

    /* convert from the default codepage to Unicode */
    if (arg) {
        argSize = static_cast<int32_t>(strlen(arg)) + 1;
        if (argSize >= MAX_UCHAR_BUFFER_SIZE(buffer)) {
            s = ufmt_defaultCPToUnicode(arg, argSize,
                    static_cast<char16_t*>(uprv_malloc(MAX_UCHAR_BUFFER_NEEDED(argSize))),
                    MAX_UCHAR_BUFFER_NEEDED(argSize));
            if(s == nullptr) {
                return 0;
            }
        }
        else {
            s = ufmt_defaultCPToUnicode(arg, argSize, buffer,
                    UPRV_LENGTHOF(buffer));
        }
    }
    else {
        s = (char16_t *)gNullStr;
    }
    len = u_strlen(s);

    /* width = minimum # of characters to write */
    /* precision = maximum # of characters to write */
    if (info->fPrecision != -1 && info->fPrecision < len) {
        len = info->fPrecision;
    }

    written = handler->pad_and_justify(context, info, s, len);

    /* clean up */
    if (gNullStr != s && buffer != s) {
        uprv_free(s);
    }

    return written;
}

static int32_t
u_printf_char_handler(const u_printf_stream_handler  *handler,
                      void                           *context,
                      ULocaleBundle                  *formatBundle,
                      const u_printf_spec_info       *info,
                      const ufmt_args                *args)
{
    (void)formatBundle;
    char16_t s[U16_MAX_LENGTH+1];
    int32_t len = 1, written;
    unsigned char arg = static_cast<unsigned char>(args[0].int64Value);

    /* convert from default codepage to Unicode */
    ufmt_defaultCPToUnicode(reinterpret_cast<const char*>(&arg), 2, s, UPRV_LENGTHOF(s));

    /* Remember that this may be an MBCS character */
    if (arg != 0) {
        len = u_strlen(s);
    }

    /* width = minimum # of characters to write */
    /* precision = maximum # of characters to write */
    /* precision is ignored when handling a char */

    written = handler->pad_and_justify(context, info, s, len);

    return written;
}

static int32_t
u_printf_double_handler(const u_printf_stream_handler  *handler,
                        void                           *context,
                        ULocaleBundle                  *formatBundle,
                        const u_printf_spec_info       *info,
                        const ufmt_args                *args)
{
    double num = args[0].doubleValue;
    UNumberFormat  *format;
    char16_t       result[UPRINTF_BUFFER_SIZE];
    char16_t       prefixBuffer[UPRINTF_BUFFER_SIZE];
    int32_t        prefixBufferLen = sizeof(prefixBuffer);
    int32_t        minDecimalDigits;
    int32_t        maxDecimalDigits;
    int32_t        resultLen;
    UErrorCode     status        = U_ZERO_ERROR;

    prefixBuffer[0] = 0;

    /* mask off any necessary bits */
    /*  if(! info->fIsLongDouble)
    num &= DBL_MAX;*/

    /* get the formatter */
    format = u_locbund_getNumberFormat(formatBundle, UNUM_DECIMAL);

    /* handle error */
    if (format == nullptr)
        return 0;

    /* save the formatter's state */
    minDecimalDigits = unum_getAttribute(format, UNUM_MIN_FRACTION_DIGITS);
    maxDecimalDigits = unum_getAttribute(format, UNUM_MAX_FRACTION_DIGITS);

    /* set the appropriate flags and number of decimal digits on the formatter */
    if(info->fPrecision != -1) {
        /* set the # of decimal digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, info->fPrecision);
    }
    else if(info->fAlt) {
        /* '#' means always show decimal point */
        /* copy of printf behavior on Solaris - '#' shows 6 digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }
    else {
        /* # of decimal digits is 6 if precision not specified regardless of locale */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }

    /* set whether to show the sign */
    if (info->fShowSign) {
        u_printf_set_sign(format, info, prefixBuffer, &prefixBufferLen, &status);
    }

    /* format the number */
    resultLen = unum_formatDouble(format, num, result, UPRINTF_BUFFER_SIZE, nullptr, &status);

    if (U_FAILURE(status)) {
        resultLen = 0;
    }

    /* restore the number format */
    /* TODO: Is this needed? */
    unum_setAttribute(format, UNUM_MIN_FRACTION_DIGITS, minDecimalDigits);
    unum_setAttribute(format, UNUM_MAX_FRACTION_DIGITS, maxDecimalDigits);

    if (info->fShowSign) {
        /* Reset back to original value regardless of what the error was */
        UErrorCode localStatus = U_ZERO_ERROR;
        u_printf_reset_sign(format, info, prefixBuffer, &prefixBufferLen, &localStatus);
    }

    return handler->pad_and_justify(context, info, result, resultLen);
}

/* HSYS */
static int32_t
u_printf_integer_handler(const u_printf_stream_handler  *handler,
                         void                           *context,
                         ULocaleBundle                  *formatBundle,
                         const u_printf_spec_info       *info,
                         const ufmt_args                *args)
{
    int64_t         num        = args[0].int64Value;
    UNumberFormat   *format;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    char16_t        prefixBuffer[UPRINTF_BUFFER_SIZE];
    int32_t         prefixBufferLen = sizeof(prefixBuffer);
    int32_t         minDigits     = -1;
    int32_t         resultLen;
    UErrorCode      status        = U_ZERO_ERROR;

    prefixBuffer[0] = 0;

    /* mask off any necessary bits */
    if (info->fIsShort)
        num = static_cast<int16_t>(num);
    else if (!info->fIsLongLong)
        num = static_cast<int32_t>(num);

    /* get the formatter */
    format = u_locbund_getNumberFormat(formatBundle, UNUM_DECIMAL);

    /* handle error */
    if (format == nullptr)
        return 0;

    /* set the appropriate flags on the formatter */

    /* set the minimum integer digits */
    if(info->fPrecision != -1) {
        /* set the minimum # of digits */
        minDigits = unum_getAttribute(format, UNUM_MIN_INTEGER_DIGITS);
        unum_setAttribute(format, UNUM_MIN_INTEGER_DIGITS, info->fPrecision);
    }

    /* set whether to show the sign */
    if(info->fShowSign) {
        u_printf_set_sign(format, info, prefixBuffer, &prefixBufferLen, &status);
    }

    /* format the number */
    resultLen = unum_formatInt64(format, num, result, UPRINTF_BUFFER_SIZE, nullptr, &status);

    if (U_FAILURE(status)) {
        resultLen = 0;
    }

    /* restore the number format */
    if (minDigits != -1) {
        unum_setAttribute(format, UNUM_MIN_INTEGER_DIGITS, minDigits);
    }

    if (info->fShowSign) {
        /* Reset back to original value regardless of what the error was */
        UErrorCode localStatus = U_ZERO_ERROR;
        u_printf_reset_sign(format, info, prefixBuffer, &prefixBufferLen, &localStatus);
    }

    return handler->pad_and_justify(context, info, result, resultLen);
}

static int32_t
u_printf_hex_handler(const u_printf_stream_handler  *handler,
                     void                           *context,
                     ULocaleBundle                  *formatBundle,
                     const u_printf_spec_info       *info,
                     const ufmt_args                *args)
{
    (void)formatBundle;
    int64_t         num        = args[0].int64Value;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    int32_t         len        = UPRINTF_BUFFER_SIZE;


    /* mask off any necessary bits */
    if (info->fIsShort)
        num &= UINT16_MAX;
    else if (!info->fIsLongLong)
        num &= UINT32_MAX;

    /* format the number, preserving the minimum # of digits */
    ufmt_64tou(result, &len, num, 16,
        static_cast<UBool>(info->fSpec == 0x0078),
        (info->fPrecision == -1 && info->fZero) ? info->fWidth : info->fPrecision);

    /* convert to alt form, if desired */
    if(num != 0 && info->fAlt && len < UPRINTF_BUFFER_SIZE - 2) {
        /* shift the formatted string right by 2 chars */
        memmove(result + 2, result, len * sizeof(char16_t));
        result[0] = 0x0030;
        result[1] = info->fSpec;
        len += 2;
    }

    return handler->pad_and_justify(context, info, result, len);
}

static int32_t
u_printf_octal_handler(const u_printf_stream_handler  *handler,
                       void                           *context,
                       ULocaleBundle                  *formatBundle,
                       const u_printf_spec_info       *info,
                       const ufmt_args                *args)
{
    (void)formatBundle;
    int64_t         num        = args[0].int64Value;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    int32_t         len        = UPRINTF_BUFFER_SIZE;


    /* mask off any necessary bits */
    if (info->fIsShort)
        num &= UINT16_MAX;
    else if (!info->fIsLongLong)
        num &= UINT32_MAX;

    /* format the number, preserving the minimum # of digits */
    ufmt_64tou(result, &len, num, 8,
        false, /* doesn't matter for octal */
        info->fPrecision == -1 && info->fZero ? info->fWidth : info->fPrecision);

    /* convert to alt form, if desired */
    if(info->fAlt && result[0] != 0x0030 && len < UPRINTF_BUFFER_SIZE - 1) {
        /* shift the formatted string right by 1 char */
        memmove(result + 1, result, len * sizeof(char16_t));
        result[0] = 0x0030;
        len += 1;
    }

    return handler->pad_and_justify(context, info, result, len);
}

static int32_t
u_printf_uinteger_handler(const u_printf_stream_handler *handler,
                          void                          *context,
                          ULocaleBundle                 *formatBundle,
                          const u_printf_spec_info      *info,
                          const ufmt_args               *args)
{
    int64_t         num        = args[0].int64Value;
    UNumberFormat   *format;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    int32_t         minDigits     = -1;
    int32_t         resultLen;
    UErrorCode      status        = U_ZERO_ERROR;

    /* TODO: Fix this once uint64_t can be formatted. */
    if (info->fIsShort)
        num &= UINT16_MAX;
    else if (!info->fIsLongLong)
        num &= UINT32_MAX;

    /* get the formatter */
    format = u_locbund_getNumberFormat(formatBundle, UNUM_DECIMAL);

    /* handle error */
    if (format == nullptr)
        return 0;

    /* set the appropriate flags on the formatter */

    /* set the minimum integer digits */
    if(info->fPrecision != -1) {
        /* set the minimum # of digits */
        minDigits = unum_getAttribute(format, UNUM_MIN_INTEGER_DIGITS);
        unum_setAttribute(format, UNUM_MIN_INTEGER_DIGITS, info->fPrecision);
    }

    /* To mirror other stdio implementations, we ignore the sign argument */

    /* format the number */
    resultLen = unum_formatInt64(format, num, result, UPRINTF_BUFFER_SIZE, nullptr, &status);

    if (U_FAILURE(status)) {
        resultLen = 0;
    }

    /* restore the number format */
    if (minDigits != -1) {
        unum_setAttribute(format, UNUM_MIN_INTEGER_DIGITS, minDigits);
    }

    return handler->pad_and_justify(context, info, result, resultLen);
}

static int32_t
u_printf_pointer_handler(const u_printf_stream_handler  *handler,
                         void                           *context,
                         ULocaleBundle                  *formatBundle,
                         const u_printf_spec_info       *info,
                         const ufmt_args                *args)
{ 
    (void)formatBundle;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    int32_t         len  = UPRINTF_BUFFER_SIZE;

    /* format the pointer in hex */
    ufmt_ptou(result, &len, args[0].ptrValue, true/*, info->fPrecision*/);

    return handler->pad_and_justify(context, info, result, len);
}

static int32_t
u_printf_scientific_handler(const u_printf_stream_handler  *handler,
                            void                           *context,
                            ULocaleBundle                  *formatBundle,
                            const u_printf_spec_info       *info,
                            const ufmt_args                *args)
{
    double num = args[0].doubleValue;
    UNumberFormat   *format;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    char16_t        prefixBuffer[UPRINTF_BUFFER_SIZE];
    int32_t         prefixBufferLen = sizeof(prefixBuffer);
    int32_t         minDecimalDigits;
    int32_t         maxDecimalDigits;
    UErrorCode      status        = U_ZERO_ERROR;
    char16_t srcExpBuf[UPRINTF_SYMBOL_BUFFER_SIZE];
    int32_t srcLen, expLen;
    int32_t resultLen;
    char16_t expBuf[UPRINTF_SYMBOL_BUFFER_SIZE];

    prefixBuffer[0] = 0;

    /* mask off any necessary bits */
    /*  if(! info->fIsLongDouble)
    num &= DBL_MAX;*/

    /* get the formatter */
    format = u_locbund_getNumberFormat(formatBundle, UNUM_SCIENTIFIC);

    /* handle error */
    if (format == nullptr)
        return 0;

    /* set the appropriate flags on the formatter */

    srcLen = unum_getSymbol(format,
        UNUM_EXPONENTIAL_SYMBOL,
        srcExpBuf,
        sizeof(srcExpBuf),
        &status);

    /* Upper/lower case the e */
    if (info->fSpec == static_cast<char16_t>(0x65) /* e */) {
        expLen = u_strToLower(expBuf, static_cast<int32_t>(sizeof(expBuf)),
            srcExpBuf, srcLen,
            formatBundle->fLocale,
            &status);
    }
    else {
        expLen = u_strToUpper(expBuf, static_cast<int32_t>(sizeof(expBuf)),
            srcExpBuf, srcLen,
            formatBundle->fLocale,
            &status);
    }

    unum_setSymbol(format,
        UNUM_EXPONENTIAL_SYMBOL,
        expBuf,
        expLen,
        &status);

    /* save the formatter's state */
    minDecimalDigits = unum_getAttribute(format, UNUM_MIN_FRACTION_DIGITS);
    maxDecimalDigits = unum_getAttribute(format, UNUM_MAX_FRACTION_DIGITS);

    /* set the appropriate flags and number of decimal digits on the formatter */
    if(info->fPrecision != -1) {
        /* set the # of decimal digits */
        if (info->fOrigSpec == static_cast<char16_t>(0x65) /* e */ ||
            info->fOrigSpec == static_cast<char16_t>(0x45) /* E */) {
            unum_setAttribute(format, UNUM_FRACTION_DIGITS, info->fPrecision);
        }
        else {
            unum_setAttribute(format, UNUM_MIN_FRACTION_DIGITS, 1);
            unum_setAttribute(format, UNUM_MAX_FRACTION_DIGITS, info->fPrecision);
        }
    }
    else if(info->fAlt) {
        /* '#' means always show decimal point */
        /* copy of printf behavior on Solaris - '#' shows 6 digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }
    else {
        /* # of decimal digits is 6 if precision not specified */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }

    /* set whether to show the sign */
    if (info->fShowSign) {
        u_printf_set_sign(format, info, prefixBuffer, &prefixBufferLen, &status);
    }

    /* format the number */
    resultLen = unum_formatDouble(format, num, result, UPRINTF_BUFFER_SIZE, nullptr, &status);

    if (U_FAILURE(status)) {
        resultLen = 0;
    }

    /* restore the number format */
    /* TODO: Is this needed? */
    unum_setAttribute(format, UNUM_MIN_FRACTION_DIGITS, minDecimalDigits);
    unum_setAttribute(format, UNUM_MAX_FRACTION_DIGITS, maxDecimalDigits);

    /* Since we're the only one using the scientific
       format, we don't need to save the old exponent value. */
    /*unum_setSymbol(format,
        UNUM_EXPONENTIAL_SYMBOL,
        srcExpBuf,
        srcLen,
        &status);*/

    if (info->fShowSign) {
        /* Reset back to original value regardless of what the error was */
        UErrorCode localStatus = U_ZERO_ERROR;
        u_printf_reset_sign(format, info, prefixBuffer, &prefixBufferLen, &localStatus);
    }

    return handler->pad_and_justify(context, info, result, resultLen);
}

static int32_t
u_printf_percent_handler(const u_printf_stream_handler  *handler,
                         void                           *context,
                         ULocaleBundle                  *formatBundle,
                         const u_printf_spec_info       *info,
                         const ufmt_args                *args)
{
    double num = args[0].doubleValue;
    UNumberFormat   *format;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    char16_t        prefixBuffer[UPRINTF_BUFFER_SIZE];
    int32_t         prefixBufferLen = sizeof(prefixBuffer);
    int32_t         minDecimalDigits;
    int32_t         maxDecimalDigits;
    int32_t         resultLen;
    UErrorCode      status        = U_ZERO_ERROR;

    prefixBuffer[0] = 0;

    /* mask off any necessary bits */
    /*  if(! info->fIsLongDouble)
    num &= DBL_MAX;*/

    /* get the formatter */
    format = u_locbund_getNumberFormat(formatBundle, UNUM_PERCENT);

    /* handle error */
    if (format == nullptr)
        return 0;

    /* save the formatter's state */
    minDecimalDigits = unum_getAttribute(format, UNUM_MIN_FRACTION_DIGITS);
    maxDecimalDigits = unum_getAttribute(format, UNUM_MAX_FRACTION_DIGITS);

    /* set the appropriate flags and number of decimal digits on the formatter */
    if(info->fPrecision != -1) {
        /* set the # of decimal digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, info->fPrecision);
    }
    else if(info->fAlt) {
        /* '#' means always show decimal point */
        /* copy of printf behavior on Solaris - '#' shows 6 digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }
    else {
        /* # of decimal digits is 6 if precision not specified */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }

    /* set whether to show the sign */
    if (info->fShowSign) {
        u_printf_set_sign(format, info, prefixBuffer, &prefixBufferLen, &status);
    }

    /* format the number */
    resultLen = unum_formatDouble(format, num, result, UPRINTF_BUFFER_SIZE, nullptr, &status);

    if (U_FAILURE(status)) {
        resultLen = 0;
    }

    /* restore the number format */
    /* TODO: Is this needed? */
    unum_setAttribute(format, UNUM_MIN_FRACTION_DIGITS, minDecimalDigits);
    unum_setAttribute(format, UNUM_MAX_FRACTION_DIGITS, maxDecimalDigits);

    if (info->fShowSign) {
        /* Reset back to original value regardless of what the error was */
        UErrorCode localStatus = U_ZERO_ERROR;
        u_printf_reset_sign(format, info, prefixBuffer, &prefixBufferLen, &localStatus);
    }

    return handler->pad_and_justify(context, info, result, resultLen);
}

static int32_t
u_printf_ustring_handler(const u_printf_stream_handler  *handler,
                         void                           *context,
                         ULocaleBundle                  *formatBundle,
                         const u_printf_spec_info       *info,
                         const ufmt_args                *args)
{
    (void)formatBundle;
    int32_t len, written;
    const char16_t* arg = static_cast<const char16_t*>(args[0].ptrValue);

    /* allocate enough space for the buffer */
    if (arg == nullptr) {
        arg = gNullStr;
    }
    len = u_strlen(arg);

    /* width = minimum # of characters to write */
    /* precision = maximum # of characters to write */
    if (info->fPrecision != -1 && info->fPrecision < len) {
        len = info->fPrecision;
    }

    /* determine if the string should be padded */
    written = handler->pad_and_justify(context, info, arg, len);

    return written;
}

static int32_t
u_printf_uchar_handler(const u_printf_stream_handler  *handler,
                       void                           *context,
                       ULocaleBundle                  *formatBundle,
                       const u_printf_spec_info       *info,
                       const ufmt_args                *args)
{
    (void)formatBundle;
    int32_t written = 0;
    char16_t arg = static_cast<char16_t>(args[0].int64Value);

    /* width = minimum # of characters to write */
    /* precision = maximum # of characters to write */
    /* precision is ignored when handling a uchar */

    /* determine if the string should be padded */
    written = handler->pad_and_justify(context, info, &arg, 1);

    return written;
}

static int32_t
u_printf_scidbl_handler(const u_printf_stream_handler  *handler,
                        void                           *context,
                        ULocaleBundle                  *formatBundle,
                        const u_printf_spec_info       *info,
                        const ufmt_args                *args)
{
    u_printf_spec_info scidbl_info;
    double      num = args[0].doubleValue;
    int32_t     retVal;
    UNumberFormat *format;
    int32_t maxSigDecimalDigits, significantDigits;

    memcpy(&scidbl_info, info, sizeof(u_printf_spec_info));

    /* determine whether to use 'd', 'e' or 'f' notation */
    if (scidbl_info.fPrecision == -1 && num == uprv_trunc(num))
    {
        /* use 'f' notation */
        scidbl_info.fSpec = 0x0066;
        scidbl_info.fPrecision = 0;
        /* call the double handler */
        retVal = u_printf_double_handler(handler, context, formatBundle, &scidbl_info, args);
    }
    else if(num < 0.0001 || (scidbl_info.fPrecision < 1 && 1000000.0 <= num)
        || (scidbl_info.fPrecision != -1 && num > uprv_pow10(scidbl_info.fPrecision)))
    {
        /* use 'e' or 'E' notation */
        scidbl_info.fSpec = scidbl_info.fSpec - 2;
        if (scidbl_info.fPrecision == -1) {
            scidbl_info.fPrecision = 5;
        }
        /* call the scientific handler */
        retVal = u_printf_scientific_handler(handler, context, formatBundle, &scidbl_info, args);
    }
    else {
        format = u_locbund_getNumberFormat(formatBundle, UNUM_DECIMAL);
        /* Check for null pointer */
        if (format == nullptr) {
            return 0;
        }
        maxSigDecimalDigits = unum_getAttribute(format, UNUM_MAX_SIGNIFICANT_DIGITS);
        significantDigits = scidbl_info.fPrecision;

        /* use 'f' notation */
        scidbl_info.fSpec = 0x0066;
        if (significantDigits == -1) {
            significantDigits = 6;
        }
        unum_setAttribute(format, UNUM_SIGNIFICANT_DIGITS_USED, true);
        unum_setAttribute(format, UNUM_MAX_SIGNIFICANT_DIGITS, significantDigits);
        /* call the double handler */
        retVal = u_printf_double_handler(handler, context, formatBundle, &scidbl_info, args);
        unum_setAttribute(format, UNUM_MAX_SIGNIFICANT_DIGITS, maxSigDecimalDigits);
        unum_setAttribute(format, UNUM_SIGNIFICANT_DIGITS_USED, false);
    }
    return retVal;
}

static int32_t
u_printf_count_handler(const u_printf_stream_handler  *handler,
                       void                           *context,
                       ULocaleBundle                  *formatBundle,
                       const u_printf_spec_info       *info,
                       const ufmt_args                *args)
{
    (void)handler;
    (void)context;
    (void)formatBundle;
    int32_t* count = static_cast<int32_t*>(args[0].ptrValue);

    /* in the special case of count, the u_printf_spec_info's width */
    /* will contain the # of chars written thus far */
    *count = info->fWidth;

    return 0;
}

static int32_t
u_printf_spellout_handler(const u_printf_stream_handler *handler,
                          void                          *context,
                          ULocaleBundle                 *formatBundle,
                          const u_printf_spec_info      *info,
                          const ufmt_args               *args)
{
    double num = args[0].doubleValue;
    UNumberFormat   *format;
    char16_t        result[UPRINTF_BUFFER_SIZE];
    char16_t        prefixBuffer[UPRINTF_BUFFER_SIZE];
    int32_t         prefixBufferLen = sizeof(prefixBuffer);
    int32_t         minDecimalDigits;
    int32_t         maxDecimalDigits;
    int32_t         resultLen;
    UErrorCode      status        = U_ZERO_ERROR;

    prefixBuffer[0] = 0;

    /* mask off any necessary bits */
    /*  if(! info->fIsLongDouble)
    num &= DBL_MAX;*/

    /* get the formatter */
    format = u_locbund_getNumberFormat(formatBundle, UNUM_SPELLOUT);

    /* handle error */
    if (format == nullptr)
        return 0;

    /* save the formatter's state */
    minDecimalDigits = unum_getAttribute(format, UNUM_MIN_FRACTION_DIGITS);
    maxDecimalDigits = unum_getAttribute(format, UNUM_MAX_FRACTION_DIGITS);

    /* set the appropriate flags and number of decimal digits on the formatter */
    if(info->fPrecision != -1) {
        /* set the # of decimal digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, info->fPrecision);
    }
    else if(info->fAlt) {
        /* '#' means always show decimal point */
        /* copy of printf behavior on Solaris - '#' shows 6 digits */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }
    else {
        /* # of decimal digits is 6 if precision not specified */
        unum_setAttribute(format, UNUM_FRACTION_DIGITS, 6);
    }

    /* set whether to show the sign */
    if (info->fShowSign) {
        u_printf_set_sign(format, info, prefixBuffer, &prefixBufferLen, &status);
    }

    /* format the number */
    resultLen = unum_formatDouble(format, num, result, UPRINTF_BUFFER_SIZE, nullptr, &status);

    if (U_FAILURE(status)) {
        resultLen = 0;
    }

    /* restore the number format */
    /* TODO: Is this needed? */
    unum_setAttribute(format, UNUM_MIN_FRACTION_DIGITS, minDecimalDigits);
    unum_setAttribute(format, UNUM_MAX_FRACTION_DIGITS, maxDecimalDigits);

    if (info->fShowSign) {
        /* Reset back to original value regardless of what the error was */
        UErrorCode localStatus = U_ZERO_ERROR;
        u_printf_reset_sign(format, info, prefixBuffer, &prefixBufferLen, &localStatus);
    }

    return handler->pad_and_justify(context, info, result, resultLen);
}

/* Use US-ASCII characters only for formatting. Most codepages have
 characters 20-7F from Unicode. Using any other codepage specific
 characters will make it very difficult to format the string on
 non-Unicode machines */
static const u_printf_info g_u_printf_infos[UPRINTF_NUM_FMT_HANDLERS] = {
/* 0x20 */
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_SIMPLE_PERCENT,UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,

/* 0x30 */
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,

/* 0x40 */
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_UCHAR,
    UFMT_EMPTY,         UFMT_SCIENTIFIC,    UFMT_EMPTY,         UFMT_SCIDBL,
#ifdef U_USE_OBSOLETE_IO_FORMATTING
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_UCHAR/*deprecated*/,
#else
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
#endif
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,

/* 0x50 */
    UFMT_PERCENT,       UFMT_EMPTY,         UFMT_EMPTY,         UFMT_USTRING,
#ifdef U_USE_OBSOLETE_IO_FORMATTING
    UFMT_EMPTY,         UFMT_USTRING/*deprecated*/,UFMT_SPELLOUT,      UFMT_EMPTY,
#else
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_SPELLOUT,      UFMT_EMPTY,
#endif
    UFMT_HEX,           UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,

/* 0x60 */
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_CHAR,
    UFMT_INT,           UFMT_SCIENTIFIC,    UFMT_DOUBLE,        UFMT_SCIDBL,
    UFMT_EMPTY,         UFMT_INT,           UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_COUNT,         UFMT_OCTAL,

/* 0x70 */
    UFMT_POINTER,       UFMT_EMPTY,         UFMT_EMPTY,         UFMT_STRING,
    UFMT_EMPTY,         UFMT_UINT,          UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_HEX,           UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
    UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,         UFMT_EMPTY,
};

/* flag characters for uprintf */
#define FLAG_MINUS 0x002D
#define FLAG_PLUS 0x002B
#define FLAG_SPACE 0x0020
#define FLAG_POUND 0x0023
#define FLAG_ZERO  0x0030
#define FLAG_PAREN 0x0028

#define ISFLAG(s)    (s) == FLAG_MINUS || \
            (s) == FLAG_PLUS || \
            (s) == FLAG_SPACE || \
            (s) == FLAG_POUND || \
            (s) == FLAG_ZERO || \
            (s) == FLAG_PAREN

/* special characters for uprintf */
#define SPEC_ASTERISK 0x002A
#define SPEC_DOLLARSIGN 0x0024
#define SPEC_PERIOD 0x002E
#define SPEC_PERCENT 0x0025

/* unicode digits */
#define DIGIT_ZERO 0x0030
#define DIGIT_ONE 0x0031
#define DIGIT_TWO 0x0032
#define DIGIT_THREE 0x0033
#define DIGIT_FOUR 0x0034
#define DIGIT_FIVE 0x0035
#define DIGIT_SIX 0x0036
#define DIGIT_SEVEN 0x0037
#define DIGIT_EIGHT 0x0038
#define DIGIT_NINE 0x0039

#define ISDIGIT(s)    (s) == DIGIT_ZERO || \
            (s) == DIGIT_ONE || \
            (s) == DIGIT_TWO || \
            (s) == DIGIT_THREE || \
            (s) == DIGIT_FOUR || \
            (s) == DIGIT_FIVE || \
            (s) == DIGIT_SIX || \
            (s) == DIGIT_SEVEN || \
            (s) == DIGIT_EIGHT || \
            (s) == DIGIT_NINE

/* u_printf modifiers */
#define MOD_H 0x0068
#define MOD_LOWERL 0x006C
#define MOD_L 0x004C

#define ISMOD(s)    (s) == MOD_H || \
            (s) == MOD_LOWERL || \
            (s) == MOD_L
/* Returns an array of the parsed argument type given in the format string. */
static ufmt_args* parseArguments(const char16_t *alias, va_list ap, UErrorCode *status) {
    ufmt_args *arglist = nullptr;
    ufmt_type_info *typelist = nullptr;
    UBool *islonglong = nullptr;
    int32_t size = 0;
    int32_t pos = 0;
    char16_t type;
    uint16_t handlerNum;
    const char16_t *aliasStart = alias;

    /* get maximum number of arguments */
    for(;;) {
        /* find % */
        while(*alias != UP_PERCENT && *alias != 0x0000) {
            alias++;
        }

        if(*alias == 0x0000) {
            break;
        }

        alias++;

        /* handle the pos number */
        if(ISDIGIT(*alias)) {

            /* handle positional parameters */
            if(ISDIGIT(*alias)) {
                pos = *alias++ - DIGIT_ZERO;

                while(ISDIGIT(*alias)) {
                    pos *= 10;
                    pos += *alias++ - DIGIT_ZERO;
                }
            }

            /* if there is no '$', don't read anything */
            if(*alias != SPEC_DOLLARSIGN) {
                return nullptr;
            }
        } else {
            return nullptr;
        }

        if (pos > size) {
            size = pos;
        }
    }

    /* create the parsed argument list */
    typelist = static_cast<ufmt_type_info*>(uprv_malloc(sizeof(ufmt_type_info) * size));
    islonglong = static_cast<UBool*>(uprv_malloc(sizeof(UBool) * size));
    arglist = static_cast<ufmt_args*>(uprv_malloc(sizeof(ufmt_args) * size));

    /* If malloc failed, return nullptr */
    if (!typelist || !islonglong || !arglist) {
        if (typelist) {
            uprv_free(typelist);
        }

        if (islonglong) {
            uprv_free(islonglong);
        }

        if (arglist) {
            uprv_free(arglist);
        }

        *status = U_MEMORY_ALLOCATION_ERROR;
        return nullptr;
    }

    /* reset alias back to the beginning */
    alias = aliasStart;

    for(;;) {
        /* find % */
        while(*alias != UP_PERCENT && *alias != 0x0000) {
            alias++;
        }

        if(*alias == 0x0000) {
            break;
        }

        alias++;

        /* handle positional parameters */
        if(ISDIGIT(*alias)) {
            pos = *alias++ - DIGIT_ZERO;

            while(ISDIGIT(*alias)) {
                pos *= 10;
                pos += *alias++ - DIGIT_ZERO;
            }
        }
        /* offset position by 1 */
        pos--;

        /* skip over everything except for the type */
        while (ISMOD(*alias) || ISFLAG(*alias) || ISDIGIT(*alias) || 
            *alias == SPEC_ASTERISK || *alias == SPEC_PERIOD || *alias == SPEC_DOLLARSIGN) {
                islonglong[pos] = false;
                if (ISMOD(*alias)) {
                    alias++;
                    if (*alias == MOD_LOWERL) {
                        islonglong[pos] = true;
                    } 
                } 
                alias++;
        }
        type = *alias;

        /* store the argument type in the correct position of the parsed argument list */
        handlerNum = static_cast<uint16_t>(type - UPRINTF_BASE_FMT_HANDLERS);
        if (handlerNum < UPRINTF_NUM_FMT_HANDLERS) {
            typelist[pos] = g_u_printf_infos[ handlerNum ].info;
        } else {
            typelist[pos] = ufmt_empty;
        }
    }

    /* store argument in arglist */
    for (pos = 0; pos < size; pos++) {
        switch (typelist[pos]) {
        case ufmt_string:
        case ufmt_ustring:
        case ufmt_pointer:
            arglist[pos].ptrValue = va_arg(ap, void*);
            break;
        case ufmt_char:
        case ufmt_uchar:
        case ufmt_int:
            if (islonglong[pos]) {
                arglist[pos].int64Value = va_arg(ap, int64_t);
            }
            else {
                arglist[pos].int64Value = va_arg(ap, int32_t);
            }
            break;
        case ufmt_float:
            arglist[pos].floatValue = static_cast<float>(va_arg(ap, double));
            break;
        case ufmt_double:
            arglist[pos].doubleValue = va_arg(ap, double);
            break;
        default:
            /* else args is ignored */
            arglist[pos].ptrValue = nullptr;
            break;
        }
    }

    uprv_free(typelist);
    uprv_free(islonglong);

    return arglist;
}

/* We parse the argument list in Unicode */
U_CFUNC int32_t
u_printf_parse(const u_printf_stream_handler *streamHandler,
               const char16_t  *fmt,
               void            *context,
               u_localized_print_string *locStringContext,
               ULocaleBundle   *formatBundle,
               int32_t         *written,
               va_list         ap)
{
    uint16_t         handlerNum;
    ufmt_args        args;
    ufmt_type_info   argType;
    u_printf_handler *handler;
    u_printf_spec    spec;
    u_printf_spec_info *info = &(spec.fInfo);

    const char16_t *alias = fmt;
    const char16_t *backup;
    const char16_t *lastAlias;
    const char16_t *orgAlias = fmt;
    /* parsed argument list */
    ufmt_args *arglist = nullptr; /* initialized it to avoid compiler warnings */
    UErrorCode status = U_ZERO_ERROR;
    if (!locStringContext || locStringContext->available >= 0) {
        /* get the parsed list of argument types */
        arglist = parseArguments(orgAlias, ap, &status);

        /* Return error if parsing failed. */
        if (U_FAILURE(status)) {
            return -1;
        }
    }
    
    /* iterate through the pattern */
    while(!locStringContext || locStringContext->available >= 0) {

        /* find the next '%' */
        lastAlias = alias;
        while(*alias != UP_PERCENT && *alias != 0x0000) {
            alias++;
        }

        /* write any characters before the '%' */
        if(alias > lastAlias) {
            *written += (streamHandler->write)(context, lastAlias, (int32_t)(alias - lastAlias));
        }

        /* break if at end of string */
        if(*alias == 0x0000) {
            break;
        }

        /* initialize spec to default values */
        spec.fWidthPos     = -1;
        spec.fPrecisionPos = -1;
        spec.fArgPos       = -1;

        uprv_memset(info, 0, sizeof(*info));
        info->fPrecision    = -1;
        info->fWidth        = -1;
        info->fPadChar      = 0x0020;

        /* skip over the initial '%' */
        alias++;

        /* Check for positional argument */
        if(ISDIGIT(*alias)) {

            /* Save the current position */
            backup = alias;

            /* handle positional parameters */
            if(ISDIGIT(*alias)) {
                spec.fArgPos = *alias++ - DIGIT_ZERO;

                while(ISDIGIT(*alias)) {
                    spec.fArgPos *= 10;
                    spec.fArgPos += *alias++ - DIGIT_ZERO;
                }
            }

            /* if there is no '$', don't read anything */
            if(*alias != SPEC_DOLLARSIGN) {
                spec.fArgPos = -1;
                alias = backup;
            }
            /* munge the '$' */
            else
                alias++;
        }

        /* Get any format flags */
        while(ISFLAG(*alias)) {
            switch(*alias++) {

                /* left justify */
            case FLAG_MINUS:
                info->fLeft = true;
                break;

                /* always show sign */
            case FLAG_PLUS:
                info->fShowSign = true;
                break;

                /* use space if no sign present */
            case FLAG_SPACE:
                info->fShowSign = true;
                info->fSpace = true;
                break;

                /* use alternate form */
            case FLAG_POUND:
                info->fAlt = true;
                break;

                /* pad with leading zeroes */
            case FLAG_ZERO:
                info->fZero = true;
                info->fPadChar = 0x0030;
                break;

                /* pad character specified */
            case FLAG_PAREN:

                /* TODO test that all four are numbers */
                /* first four characters are hex values for pad char */
                info->fPadChar = (char16_t)ufmt_digitvalue(*alias++);
                info->fPadChar = (char16_t)((info->fPadChar * 16) + ufmt_digitvalue(*alias++));
                info->fPadChar = (char16_t)((info->fPadChar * 16) + ufmt_digitvalue(*alias++));
                info->fPadChar = (char16_t)((info->fPadChar * 16) + ufmt_digitvalue(*alias++));

                /* final character is ignored */
                alias++;

                break;
            }
        }

        /* Get the width */

        /* width is specified out of line */
        if(*alias == SPEC_ASTERISK) {

            info->fWidth = -2;

            /* Skip the '*' */
            alias++;

            /* Save the current position */
            backup = alias;

            /* handle positional parameters */
            if(ISDIGIT(*alias)) {
                spec.fWidthPos = *alias++ - DIGIT_ZERO;

                while(ISDIGIT(*alias)) {
                    spec.fWidthPos *= 10;
                    spec.fWidthPos += *alias++ - DIGIT_ZERO;
                }
            }

            /* if there is no '$', don't read anything */
            if(*alias != SPEC_DOLLARSIGN) {
                spec.fWidthPos = -1;
                alias = backup;
            }
            /* munge the '$' */
            else
                alias++;
        }
        /* read the width, if present */
        else if(ISDIGIT(*alias)){
            info->fWidth = *alias++ - DIGIT_ZERO;

            while(ISDIGIT(*alias)) {
                info->fWidth *= 10;
                info->fWidth += *alias++ - DIGIT_ZERO;
            }
        }

        /* Get the precision */

        if(*alias == SPEC_PERIOD) {

            /* eat up the '.' */
            alias++;

            /* precision is specified out of line */
            if(*alias == SPEC_ASTERISK) {

                info->fPrecision = -2;

                /* Skip the '*' */
                alias++;

                /* save the current position */
                backup = alias;

                /* handle positional parameters */
                if(ISDIGIT(*alias)) {
                    spec.fPrecisionPos = *alias++ - DIGIT_ZERO;

                    while(ISDIGIT(*alias)) {
                        spec.fPrecisionPos *= 10;
                        spec.fPrecisionPos += *alias++ - DIGIT_ZERO;
                    }

                    /* if there is no '$', don't read anything */
                    if(*alias != SPEC_DOLLARSIGN) {
                        spec.fPrecisionPos = -1;
                        alias = backup;
                    }
                    else {
                        /* munge the '$' */
                        alias++;
                    }
                }
            }
            /* read the precision */
            else if(ISDIGIT(*alias)){
                info->fPrecision = *alias++ - DIGIT_ZERO;

                while(ISDIGIT(*alias)) {
                    info->fPrecision *= 10;
                    info->fPrecision += *alias++ - DIGIT_ZERO;
                }
            }
        }

        /* Get any modifiers */
        if(ISMOD(*alias)) {
            switch(*alias++) {

                /* short */
            case MOD_H:
                info->fIsShort = true;
                break;

                /* long or long long */
            case MOD_LOWERL:
                if(*alias == MOD_LOWERL) {
                    info->fIsLongLong = true;
                    /* skip over the next 'l' */
                    alias++;
                }
                else
                    info->fIsLong = true;
                break;

                /* long double */
            case MOD_L:
                info->fIsLongDouble = true;
                break;
            }
        }

        /* finally, get the specifier letter */
        info->fSpec = *alias++;
        info->fOrigSpec = info->fSpec;

        /* fill in the precision and width, if specified out of line */

        /* width specified out of line */
        if(spec.fInfo.fWidth == -2) {
            if(spec.fWidthPos == -1) {
                /* read the width from the argument list */
                info->fWidth = va_arg(ap, int32_t);
            }
            /* else handle positional parameter */

            /* if it's negative, take the absolute value and set left alignment */
            if(info->fWidth < 0) {
                info->fWidth *= -1; /* Make positive */
                info->fLeft = true;
            }
        }

        /* precision specified out of line */
        if(info->fPrecision == -2) {
            if(spec.fPrecisionPos == -1) {
                /* read the precision from the argument list */
                info->fPrecision = va_arg(ap, int32_t);
            }
            /* else handle positional parameter */

            /* if it's negative, set it to zero */
            if(info->fPrecision < 0)
                info->fPrecision = 0;
        }

        handlerNum = (uint16_t)(info->fSpec - UPRINTF_BASE_FMT_HANDLERS);
        if (handlerNum < UPRINTF_NUM_FMT_HANDLERS) {
            /* query the info function for argument information */
            argType = g_u_printf_infos[ handlerNum ].info;

            /* goto the correct argument on arg_list if position is specified */
            if (spec.fArgPos > 0) {
                /* offset position by 1 */
                spec.fArgPos--;
                switch(argType) {
                case ufmt_count:
                    /* set the spec's width to the # of chars written */
                    info->fWidth = *written;
                    /* fall through to set the pointer */
                    U_FALLTHROUGH;
                case ufmt_string:
                case ufmt_ustring:
                case ufmt_pointer:
                    args.ptrValue = arglist[spec.fArgPos].ptrValue;
                    break;
                case ufmt_char:
                case ufmt_uchar:
                case ufmt_int:
                    args.int64Value = arglist[spec.fArgPos].int64Value;
                    break;
                case ufmt_float:
                    args.floatValue = arglist[spec.fArgPos].floatValue;
                    break;
                case ufmt_double:
                    args.doubleValue = arglist[spec.fArgPos].doubleValue;
                    break;
                default:
                    /* else args is ignored */
                    args.ptrValue = nullptr;
                    break;
                }
            } else { /* no positional argument specified */
                switch(argType) {
                case ufmt_count:
                    /* set the spec's width to the # of chars written */
                    info->fWidth = *written;
                    /* fall through to set the pointer */
                    U_FALLTHROUGH;
                case ufmt_string:
                case ufmt_ustring:
                case ufmt_pointer:
                    args.ptrValue = va_arg(ap, void*);
                    break;
                case ufmt_char:
                case ufmt_uchar:
                case ufmt_int:
                    if (info->fIsLongLong) {
                        args.int64Value = va_arg(ap, int64_t);
                    }
                    else {
                        args.int64Value = va_arg(ap, int32_t);
                    }
                    break;
                case ufmt_float:
                    args.floatValue = (float) va_arg(ap, double);
                    break;
                case ufmt_double:
                    args.doubleValue = va_arg(ap, double);
                    break;
                default:
                    /* else args is ignored */
                    args.ptrValue = nullptr;
                    break;
                }
            }

            /* call the handler function */
            handler = g_u_printf_infos[ handlerNum ].handler;
            if (handler != nullptr) {
                *written += (*handler)(streamHandler, context, formatBundle, info, &args);
            }
            else {
                /* just echo unknown tags */
                *written += (streamHandler->write)(context, fmt, (int32_t)(alias - lastAlias));
            }
        }
        else {
            /* just echo unknown tags */
            *written += (streamHandler->write)(context, fmt, (int32_t)(alias - lastAlias));
        }
    }
    /* delete parsed argument list */
    if (arglist != nullptr) {
        uprv_free(arglist);
    }
    /* return # of characters in this format that have been parsed. */
    return (int32_t)(alias - fmt);
}

#endif /* #if !UCONFIG_NO_FORMATTING */