/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Chris Torek.
 *
 * Copyright (c) 2011 The FreeBSD Foundation
 *
 * Portions of this software were developed by David Chisnall
 * under sponsorship from the FreeBSD Foundation.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * This file defines common routines used by both printf and wprintf.
 * You must define CHAR to either char or wchar_t prior to including this.
 */



#define dtoa            __dtoa
#define freedtoa        __freedtoa

#include <float.h>
#include <math.h>
#include "floatio.h"
#include "gdtoa.h"

#define DEFPREC         6

static int exponent(CHAR *, int, CHAR);


static CHAR     *__ujtoa(uintmax_t, CHAR *, int, int, const char *);
static CHAR     *__ultoa(u_long, CHAR *, int, int, const char *);

#define NIOV 8
struct io_state {
        FILE *fp;
        struct __suio uio;      /* output information: summary */
        struct __siov iov[NIOV];/* ... and individual io vectors */
};

static inline void
io_init(struct io_state *iop, FILE *fp)
{

        iop->uio.uio_iov = iop->iov;
        iop->uio.uio_resid = 0;
        iop->uio.uio_iovcnt = 0;
        iop->fp = fp;
}

/*
 * WARNING: The buffer passed to io_print() is not copied immediately; it must
 * remain valid until io_flush() is called.
 */
static inline int
io_print(struct io_state *iop, const CHAR * __restrict ptr, int len, locale_t locale)
{

        iop->iov[iop->uio.uio_iovcnt].iov_base = (char *)ptr;
        iop->iov[iop->uio.uio_iovcnt].iov_len = len;
        iop->uio.uio_resid += len;
        if (++iop->uio.uio_iovcnt >= NIOV)
                return (__sprint(iop->fp, &iop->uio, locale));
        else
                return (0);
}

/*
 * Choose PADSIZE to trade efficiency vs. size.  If larger printf
 * fields occur frequently, increase PADSIZE and make the initialisers
 * below longer.
 */
#define PADSIZE 16              /* pad chunk size */
static const CHAR blanks[PADSIZE] =
{' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' ',' '};
static const CHAR zeroes[PADSIZE] =
{'0','0','0','0','0','0','0','0','0','0','0','0','0','0','0','0'};

/*
 * Pad with blanks or zeroes. 'with' should point to either the blanks array
 * or the zeroes array.
 */
static inline int
io_pad(struct io_state *iop, int howmany, const CHAR * __restrict with,
                locale_t locale)
{
        int n;

        while (howmany > 0) {
                n = (howmany >= PADSIZE) ? PADSIZE : howmany;
                if (io_print(iop, with, n, locale))
                        return (-1);
                howmany -= n;
        }
        return (0);
}

/*
 * Print exactly len characters of the string spanning p to ep, truncating
 * or padding with 'with' as necessary.
 */
static inline int
io_printandpad(struct io_state *iop, const CHAR *p, const CHAR *ep,
               int len, const CHAR * __restrict with, locale_t locale)
{
        int p_len;

        p_len = ep - p;
        if (p_len > len)
                p_len = len;
        if (p_len > 0) {
                if (io_print(iop, p, p_len, locale))
                        return (-1);
        } else {
                p_len = 0;
        }
        return (io_pad(iop, len - p_len, with, locale));
}

static inline int
io_flush(struct io_state *iop, locale_t locale)
{

        return (__sprint(iop->fp, &iop->uio, locale));
}

/*
 * Convert an unsigned long to ASCII for printf purposes, returning
 * a pointer to the first character of the string representation.
 * Octal numbers can be forced to have a leading zero; hex numbers
 * use the given digits.
 */
static CHAR *
__ultoa(u_long val, CHAR *endp, int base, int octzero, const char *xdigs)
{
        CHAR *cp = endp;
        long sval;

        /*
         * Handle the three cases separately, in the hope of getting
         * better/faster code.
         */
        switch (base) {
        case 10:
                if (val < 10) { /* many numbers are 1 digit */
                        *--cp = to_char(val);
                        return (cp);
                }
                /*
                 * On many machines, unsigned arithmetic is harder than
                 * signed arithmetic, so we do at most one unsigned mod and
                 * divide; this is sufficient to reduce the range of
                 * the incoming value to where signed arithmetic works.
                 */
                if (val > LONG_MAX) {
                        *--cp = to_char(val % 10);
                        sval = val / 10;
                } else
                        sval = val;
                do {
                        *--cp = to_char(sval % 10);
                        sval /= 10;
                } while (sval != 0);
                break;

        case 2:
                do {
                        *--cp = to_char(val & 1);
                        val >>= 1;
                } while (val);
                break;

        case 8:
                do {
                        *--cp = to_char(val & 7);
                        val >>= 3;
                } while (val);
                if (octzero && *cp != '0')
                        *--cp = '0';
                break;

        case 16:
                do {
                        *--cp = xdigs[val & 15];
                        val >>= 4;
                } while (val);
                break;

        default:                        /* oops */
                abort();
        }
        return (cp);
}

/* Identical to __ultoa, but for intmax_t. */
static CHAR *
__ujtoa(uintmax_t val, CHAR *endp, int base, int octzero, const char *xdigs)
{
        CHAR *cp = endp;
        intmax_t sval;

        /* quick test for small values; __ultoa is typically much faster */
        /* (perhaps instead we should run until small, then call __ultoa?) */
        if (val <= ULONG_MAX)
                return (__ultoa((u_long)val, endp, base, octzero, xdigs));
        switch (base) {
        case 10:
                if (val < 10) {
                        *--cp = to_char(val % 10);
                        return (cp);
                }
                if (val > INTMAX_MAX) {
                        *--cp = to_char(val % 10);
                        sval = val / 10;
                } else
                        sval = val;
                do {
                        *--cp = to_char(sval % 10);
                        sval /= 10;
                } while (sval != 0);
                break;

        case 2:
                do {
                        *--cp = to_char(val & 1);
                        val >>= 1;
                } while (val);
                break;

        case 8:
                do {
                        *--cp = to_char(val & 7);
                        val >>= 3;
                } while (val);
                if (octzero && *cp != '0')
                        *--cp = '0';
                break;

        case 16:
                do {
                        *--cp = xdigs[val & 15];
                        val >>= 4;
                } while (val);
                break;

        default:
                abort();
        }
        return (cp);
}


static int
exponent(CHAR *p0, int exp, CHAR fmtch)
{
        CHAR *p, *t;
        CHAR expbuf[MAXEXPDIG];

        p = p0;
        *p++ = fmtch;
        if (exp < 0) {
                exp = -exp;
                *p++ = '-';
        }
        else
                *p++ = '+';
        t = expbuf + MAXEXPDIG;
        if (exp > 9) {
                do {
                        *--t = to_char(exp % 10);
                } while ((exp /= 10) > 9);
                *--t = to_char(exp);
                for (; t < expbuf + MAXEXPDIG; *p++ = *t++);
        }
        else {
                /*
                 * Exponents for decimal floating point conversions
                 * (%[eEgG]) must be at least two characters long,
                 * whereas exponents for hexadecimal conversions can
                 * be only one character long.
                 */
                if (fmtch == 'e' || fmtch == 'E')
                        *p++ = '0';
                *p++ = to_char(exp);
        }
        return (p - p0);
}