/* $NetBSD: subr_prf.c,v 1.31 2024/08/31 07:12:57 mlelstv Exp $ */

/* $NetBSD: subr_prf.c,v 1.31 2024/08/31 07:12:57 mlelstv Exp $ */

/*-
* Copyright (c) 1993
* The Regents of the University of California. All rights reserved.
*
* 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.
*
* @(#)printf.c 8.1 (Berkeley) 6/11/93
*/

/*
* Scaled down version of printf(3).
*/

#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/stdint.h> /* XXX: for intptr_t */

#include "stand.h"

#ifdef LIBSA_PRINTF_LONGLONG_SUPPORT
#define INTMAX_T longlong_t
#define UINTMAX_T u_longlong_t
#else
#define INTMAX_T long
#define UINTMAX_T u_long
#endif

#if 0 /* XXX: abuse intptr_t until the situation with ptrdiff_t is clear */
#define PTRDIFF_T ptrdiff_t
#else
#define PTRDIFF_T intptr_t
#endif

#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
static void kprintn(void (*)(int), UINTMAX_T, int, int, int);
#else
static void kprintn(void (*)(int), UINTMAX_T, int);
#endif
static void sputchar(int);
static void kdoprnt(void (*)(int), const char *, va_list);

static char *sbuf, *ebuf;

const char hexdigits[16] = "0123456789abcdef";

#define LONG 0x01
#ifdef LIBSA_PRINTF_LONGLONG_SUPPORT
#define LLONG 0x02
#endif
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
#define ALT 0x04
#define SPACE 0x08
#define LADJUST 0x10
#define SIGN 0x20
#define ZEROPAD 0x40
#define NEGATIVE 0x80
#define KPRINTN(base) kprintn(put, ul, base, lflag, width)
#define RADJUSTZEROPAD() \
do { \
if ((lflag & (ZEROPAD|LADJUST)) == ZEROPAD) { \
while (width-- > 0) \
put('0'); \
} \
} while (/*CONSTCOND*/0)
#define LADJUSTPAD() \
do { \
if (lflag & LADJUST) { \
while (width-- > 0) \
put(' '); \
} \
} while (/*CONSTCOND*/0)
#define RADJUSTPAD() \
do { \
if ((lflag & (ZEROPAD|LADJUST)) == 0) { \
while (width-- > 0) \
put(' '); \
} \
} while (/*CONSTCOND*/0)
#else /* LIBSA_PRINTF_WIDTH_SUPPORT */
#define KPRINTN(base) kprintn(put, ul, base)
#define RADJUSTZEROPAD() /**/
#define LADJUSTPAD() /**/
#define RADJUSTPAD() /**/
#endif /* LIBSA_PRINTF_WIDTH_SUPPORT */

#ifdef LIBSA_PRINTF_LONGLONG_SUPPORT
#define KPRINT(base) \
do { \
ul = (lflag & LLONG) \
? va_arg(ap, u_longlong_t) \
: (lflag & LONG) \
? va_arg(ap, u_long) \
: va_arg(ap, u_int); \
KPRINTN(base); \
} while (/*CONSTCOND*/0)
#else /* LIBSA_PRINTF_LONGLONG_SUPPORT */
#define KPRINT(base) \
do { \
ul = (lflag & LONG) \
? va_arg(ap, u_long) : va_arg(ap, u_int); \
KPRINTN(base); \
} while (/*CONSTCOND*/0)
#endif /* LIBSA_PRINTF_LONGLONG_SUPPORT */

static void
null_sputchar(int c)
{
sbuf++;
}

static void
sputchar(int c)
{

if (sbuf < ebuf)
*sbuf++ = c;
}

void
vprintf(const char *fmt, va_list ap)
{

kdoprnt(putchar, fmt, ap);
}

int
vsnprintf(char *buf, size_t size, const char *fmt, va_list ap)
{

sbuf = buf;
ebuf = buf + size - 1;
kdoprnt(buf == NULL ? null_sputchar : sputchar, fmt, ap);
if (buf != NULL)
*sbuf = '\0';
return sbuf - buf;
}

static void
kdoprnt(void (*put)(int), const char *fmt, va_list ap)
{
char *p;
int ch;
UINTMAX_T ul;
int lflag;
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
int width;
char *q;
#endif

for (;;) {
while ((ch = *fmt++) != '%') {
if (ch == '\0')
return;
put(ch);
}
lflag = 0;
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
width = 0;
#endif
reswitch:
switch (ch = *fmt++) {
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
case '#':
lflag |= ALT;
goto reswitch;
case ' ':
lflag |= SPACE;
goto reswitch;
case '-':
lflag |= LADJUST;
goto reswitch;
case '+':
lflag |= SIGN;
goto reswitch;
case '0':
if (width == 0) {
lflag |= ZEROPAD;
goto reswitch;
}
/* FALLTHROUGH */
case '1': case '2': case '3': case '4': case '5':
case '6': case '7': case '8': case '9':
for (;;) {
width *= 10;
width += ch - '0';
ch = *fmt;
if ((unsigned)ch - '0' > 9)
break;
++fmt;
}
goto reswitch;
#endif
case 'l':
#ifdef LIBSA_PRINTF_LONGLONG_SUPPORT
if (*fmt == 'l') {
++fmt;
lflag |= LLONG;
} else
#endif
lflag |= LONG;
goto reswitch;
case 'j':
#ifdef LIBSA_PRINTF_LONGLONG_SUPPORT
if (sizeof(intmax_t) == sizeof(long long))
lflag |= LLONG;
else
#endif
if (sizeof(intmax_t) == sizeof(long))
lflag |= LONG;
goto reswitch;
case 't':
if (sizeof(PTRDIFF_T) == sizeof(long))
lflag |= LONG;
goto reswitch;
case 'z':
if (sizeof(ssize_t) == sizeof(long))
lflag |= LONG;
goto reswitch;
case 'c':
ch = va_arg(ap, int);
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
--width;
#endif
RADJUSTPAD();
put(ch & 0xFF);
LADJUSTPAD();
break;
case 's':
p = va_arg(ap, char *);
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
for (q = p; *q != '\0'; ++q)
continue;
width -= q - p;
#endif
RADJUSTPAD();
while ((ch = (unsigned char)*p++))
put(ch);
LADJUSTPAD();
break;
case 'd':
ul =
#ifdef LIBSA_PRINTF_LONGLONG_SUPPORT
(lflag & LLONG) ? va_arg(ap, longlong_t) :
#endif
(lflag & LONG) ? va_arg(ap, long) : va_arg(ap, int);
if ((INTMAX_T)ul < 0) {
ul = -(INTMAX_T)ul;
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
lflag |= NEGATIVE;
#else
put('-');
#endif
}
KPRINTN(10);
break;
case 'o':
KPRINT(8);
break;
case 'u':
KPRINT(10);
break;
case 'p':
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
lflag |= (LONG|ALT);
#else
put('0');
put('x');
#endif
/* FALLTHROUGH */
case 'x':
KPRINT(16);
break;
default:
if (ch == '\0')
return;
put(ch);
break;
}
}
}

static void
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
kprintn(void (*put)(int), UINTMAX_T ul, int base, int lflag, int width)
#else
kprintn(void (*put)(int), UINTMAX_T ul, int base)
#endif
{
/* hold a INTMAX_T in base 8 */
char *p, buf[(sizeof(INTMAX_T) * NBBY / 3) + 1 + 2 /* ALT + SIGN */];
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
char *q;
#endif

p = buf;
do {
*p++ = hexdigits[ul % base];
} while (ul /= base);
#ifdef LIBSA_PRINTF_WIDTH_SUPPORT
q = p;
if (lflag & ALT && *(p - 1) != '0') {
if (base == 8) {
*p++ = '0';
} else if (base == 16) {
*p++ = 'x';
*p++ = '0';
}
}
if (lflag & NEGATIVE)
*p++ = '-';
else if (lflag & SIGN)
*p++ = '+';
else if (lflag & SPACE)
*p++ = ' ';
width -= p - buf;
if (lflag & ZEROPAD) {
while (p > q)
put(*--p);
}
#endif
RADJUSTPAD();
RADJUSTZEROPAD();
do {
put(*--p);
} while (p > buf);
LADJUSTPAD();
}