Source to stand/printf.c
/*-
* Copyright (c) 1991 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. 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 5.6 (Berkeley) 5/25/91
*/
/*
* Scaled down version of printf(3).
*
* One additional format:
*
* The format %b is supported to decode error registers.
* Its usage is:
*
* printf("reg=%b\n", regval, "<base><arg>*");
*
* where <base> is the output base expressed as a control character, e.g.
* \10 gives octal; \20 gives hex. Each arg is a sequence of characters,
* the first of which gives the bit number to be inspected (origin 1), and
* the next characters (up to a control character, i.e. a character <= 32),
* give the name of the register. Thus:
*
* printf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
*
* would produce output:
*
* reg=3<BITTWO,BITONE>
*/
#include <sys/cdefs.h>
#include <sys/types.h>
/*
* Note that stdarg.h and the ANSI style va_start macro is used for both
* ANSI and traditional C compilers.
*/
#define KERNEL
#include <machine/stdarg.h>
#undef KERNEL
static void kprintn __P((u_long, int));
void
#if __STDC__
printf(const char *fmt, ...)
#else
printf(fmt /* , va_alist */)
char *fmt;
#endif
{
register char *p;
register int ch, n;
unsigned long ul;
int lflag, set;
va_list ap;
va_start(ap, fmt);
for (;;) {
while ((ch = *fmt++) != '%') {
if (ch == '\0')
return;
putchar(ch);
}
lflag = 0;
reswitch: switch (ch = *fmt++) {
case 'l':
lflag = 1;
goto reswitch;
case 'b':
ul = va_arg(ap, int);
p = va_arg(ap, char *);
kprintn(ul, *p++);
if (!ul)
break;
for (set = 0; n = *p++;) {
if (ul & (1 << (n - 1))) {
putchar(set ? ',' : '<');
for (; (n = *p) > ' '; ++p)
putchar(n);
set = 1;
} else
for (; *p > ' '; ++p);
}
if (set)
putchar('>');
break;
case 'c':
ch = va_arg(ap, int);
putchar(ch & 0x7f);
break;
case 's':
p = va_arg(ap, char *);
while (ch = *p++)
putchar(ch);
break;
case 'd':
ul = lflag ?
va_arg(ap, long) : va_arg(ap, int);
if ((long)ul < 0) {
putchar('-');
ul = -(long)ul;
}
kprintn(ul, 10);
break;
case 'o':
ul = lflag ?
va_arg(ap, u_long) : va_arg(ap, u_int);
kprintn(ul, 8);
break;
case 'u':
ul = lflag ?
va_arg(ap, u_long) : va_arg(ap, u_int);
kprintn(ul, 10);
break;
case 'x':
ul = lflag ?
va_arg(ap, u_long) : va_arg(ap, u_int);
kprintn(ul, 16);
break;
default:
putchar('%');
if (lflag)
putchar('l');
putchar(ch);
}
}
va_end(ap);
}
static void
kprintn(ul, base)
unsigned long ul;
int base;
{
/* hold a long in base 8 */
char *p, buf[(sizeof(long) * NBBY / 3) + 1];
p = buf;
do {
*p++ = "0123456789abcdef"[ul % base];
} while (ul /= base);
do {
putchar(*--p);
} while (p > buf);
}