iovprintf.c

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1986, 1988, 1991, 1993
 *  The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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.
 *
 *  @(#)subr_prf.c  8.3 (Berkeley) 1/21/94
 */

#include <rtems/score/io.h>

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: head/sys/kern/subr_prf.c 336417 2018-07-17 14:56:54Z markj $");

#include <sys/param.h>
#include <string.h>

/* Max number conversion buffer length: a intmax_t in base 8, plus NUL byte. */
#define MAXNBUF (howmany(sizeof(intmax_t) * NBBY, 3) + 1)

static inline int imax(int a, int b) { return (a > b ? a : b); }

static char const hex2ascii_data[2][16] = {
    { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
      'a', 'b', 'c', 'd', 'e', 'f' },
    { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
      'A', 'B', 'C', 'D', 'E', 'F' }
};

static inline char
hex2ascii(int hex)
{

    return (hex2ascii_data[0][hex]);
}

/*
 * Put a NUL-terminated ASCII number (base <= 16) in a buffer in reverse
 * order; return an optional length and a pointer to the last character
 * written in the buffer (i.e., the first character of the string).
 * The buffer pointed to by `nbuf' must have length >= MAXNBUF.
 */
static char *
ksprintn(char *nbuf, uintmax_t num, int base, int *lenp, int upper)
{
    char *p;

    p = nbuf;
    *p = '\0';
    do {
        *++p = hex2ascii_data[upper][num % base];
    } while (num /= base);
    if (lenp)
        *lenp = p - nbuf;
    return (p);
}

int
_IO_Vprintf(IO_Put_char put_char, void *arg, char const *fmt, va_list ap)
{
#define PCHAR(c) {int cc=(c); (*put_char)(cc, arg); retval++; }
    char nbuf[MAXNBUF];
    const char *p, *percent, *q;
    u_char *up;
    int ch, n;
    uintmax_t num;
    int base, lflag, tmp, width, ladjust, sharpflag, neg, sign, dot;
    int cflag, hflag, jflag;
    RTEMS_STATIC_ASSERT(sizeof(intmax_t) == sizeof(long long), _IO_Vprintf_j);
#if __SIZEOF_PTRDIFF_T__ == __SIZEOF_LONG__
#define tflag lflag
#else
    int tflag;
#endif
#if __SIZEOF_SIZE_T__ == __SIZEOF_LONG__
#define zflag lflag
#else
    int zflag;
#endif
    int dwidth, upper;
    char padc;
    int stop = 0, retval = 0;

    num = 0;

    if (fmt == NULL)
        fmt = "(fmt null)\n";

    for (;;) {
        padc = ' ';
        width = 0;
        while ((ch = (u_char)*fmt++) != '%' || stop) {
            if (ch == '\0')
                return (retval);
            PCHAR(ch);
        }
        percent = fmt - 1;
        lflag = 0; ladjust = 0; sharpflag = 0; neg = 0;
        sign = 0; dot = 0; dwidth = 0; upper = 0;
        cflag = 0; hflag = 0; jflag = 0; tflag = 0; zflag = 0;
reswitch:   switch (ch = (u_char)*fmt++) {
        case '.':
            dot = 1;
            goto reswitch;
        case '#':
            sharpflag = 1;
            goto reswitch;
        case '+':
            sign = 1;
            goto reswitch;
        case '-':
            ladjust = 1;
            goto reswitch;
        case '%':
            PCHAR(ch);
            break;
        case '*':
            if (!dot) {
                width = va_arg(ap, int);
                if (width < 0) {
                    ladjust = !ladjust;
                    width = -width;
                }
            } else {
                dwidth = va_arg(ap, int);
            }
            goto reswitch;
        case '0':
            if (!dot) {
                padc = '0';
                goto reswitch;
            }
            /* FALLTHROUGH */
        case '1': case '2': case '3': case '4':
        case '5': case '6': case '7': case '8': case '9':
                for (n = 0;; ++fmt) {
                    n = n * 10 + ch - '0';
                    ch = *fmt;
                    if (ch < '0' || ch > '9')
                        break;
                }
            if (dot)
                dwidth = n;
            else
                width = n;
            goto reswitch;
        case 'c':
            width -= 1;

            if (!ladjust && width > 0)
                while (width--)
                    PCHAR(padc);
            PCHAR(va_arg(ap, int));
            if (ladjust && width > 0)
                while (width--)
                    PCHAR(padc);
            break;
        case 'D':
            up = va_arg(ap, u_char *);
            p = va_arg(ap, char *);
            if (!width)
                width = 16;
            while(width--) {
                PCHAR(hex2ascii(*up >> 4));
                PCHAR(hex2ascii(*up & 0x0f));
                up++;
                if (width)
                    for (q=p;*q;q++)
                        PCHAR(*q);
            }
            break;
        case 'd':
        case 'i':
            base = 10;
            sign = 1;
            goto handle_sign;
        case 'h':
            if (hflag) {
                hflag = 0;
                cflag = 1;
            } else
                hflag = 1;
            goto reswitch;
        case 'j':
            jflag = 1;
            goto reswitch;
        case 'l':
            if (lflag) {
                jflag = 1;
            } else
                lflag = 1;
            goto reswitch;
        case 'o':
            base = 8;
            goto handle_nosign;
        case 'p':
            base = 16;
            sharpflag = (width == 0);
            sign = 0;
            num = (uintptr_t)va_arg(ap, void *);
            goto number;
        case 's':
            p = va_arg(ap, char *);
            if (p == NULL)
                p = "(null)";
            if (!dot)
                n = strlen (p);
            else
                for (n = 0; n < dwidth && p[n]; n++)
                    continue;

            width -= n;

            if (!ladjust && width > 0)
                while (width--)
                    PCHAR(padc);
            while (n--)
                PCHAR(*p++);
            if (ladjust && width > 0)
                while (width--)
                    PCHAR(padc);
            break;
        case 't':
            tflag = 1;
            goto reswitch;
        case 'u':
            base = 10;
            goto handle_nosign;
        case 'X':
            upper = 1;
        case 'x':
            base = 16;
            goto handle_nosign;
        case 'y':
            base = 16;
            sign = 1;
            goto handle_sign;
        case 'z':
            zflag = 1;
            goto reswitch;
handle_nosign:
            sign = 0;
            if (jflag)
                num = va_arg(ap, uintmax_t);
#if __SIZEOF_PTRDIFF_T__ != __SIZEOF_LONG__
            else if (tflag)
                num = va_arg(ap, ptrdiff_t);
#endif
            else if (lflag)
                num = va_arg(ap, u_long);
#if __SIZEOF_SIZE_T__ != __SIZEOF_LONG__
            else if (zflag)
                num = va_arg(ap, size_t);
#endif
            else if (hflag)
                num = (u_short)va_arg(ap, int);
            else if (cflag)
                num = (u_char)va_arg(ap, int);
            else
                num = va_arg(ap, u_int);
            goto number;
handle_sign:
            if (jflag)
                num = va_arg(ap, intmax_t);
#if __SIZEOF_PTRDIFF_T__ == __SIZEOF_LONG__
            else if (tflag)
                num = va_arg(ap, ptrdiff_t);
#endif
            else if (lflag)
                num = va_arg(ap, long);
#if __SIZEOF_SIZE_T__ == __SIZEOF_LONG__
            else if (zflag)
                num = va_arg(ap, ssize_t);
#endif
            else if (hflag)
                num = (short)va_arg(ap, int);
            else if (cflag)
                num = (char)va_arg(ap, int);
            else
                num = va_arg(ap, int);
number:
            if (sign && (intmax_t)num < 0) {
                neg = 1;
                num = -(intmax_t)num;
            }
            p = ksprintn(nbuf, num, base, &n, upper);
            tmp = 0;
            if (sharpflag && num != 0) {
                if (base == 8)
                    tmp++;
                else if (base == 16)
                    tmp += 2;
            }
            if (neg)
                tmp++;

            if (!ladjust && padc == '0')
                dwidth = width - tmp;
            width -= tmp + imax(dwidth, n);
            dwidth -= n;
            if (!ladjust)
                while (width-- > 0)
                    PCHAR(' ');
            if (neg)
                PCHAR('-');
            if (sharpflag && num != 0) {
                if (base == 8) {
                    PCHAR('0');
                } else if (base == 16) {
                    PCHAR('0');
                    PCHAR('x');
                }
            }
            while (dwidth-- > 0)
                PCHAR('0');

            while (*p)
                PCHAR(*p--);

            if (ladjust)
                while (width-- > 0)
                    PCHAR(' ');

            break;
        default:
            while (percent < fmt)
                PCHAR(*percent++);
            /*
             * Since we ignore a formatting argument it is no
             * longer safe to obey the remaining formatting
             * arguments as the arguments will no longer match
             * the format specs.
             */
            stop = 1;
            break;
        }
    }
#undef PCHAR
}