189 lines
3.5 KiB
C
Executable file
189 lines
3.5 KiB
C
Executable file
/* printf() - kernel printf() Author: Kees J. Bot
|
|
* 15 Jan 1994
|
|
*/
|
|
#define nil 0
|
|
#include <stdarg.h>
|
|
#include <stddef.h>
|
|
#include <limits.h>
|
|
|
|
#define isdigit(c) ((unsigned) ((c) - '0') < (unsigned) 10)
|
|
|
|
#if !__STDC__
|
|
/* Classic C stuff, ignore. */
|
|
void kputc();
|
|
int printf(fmt) char *fmt;
|
|
#else
|
|
|
|
/* Printf() uses kputc() to print characters. */
|
|
void kputc(int c);
|
|
|
|
int printf(const char *fmt, ...)
|
|
#endif
|
|
{
|
|
int c;
|
|
enum { LEFT, RIGHT } adjust;
|
|
enum { LONG, INT } intsize;
|
|
int fill;
|
|
int width, max, len, base;
|
|
static char X2C_tab[]= "0123456789ABCDEF";
|
|
static char x2c_tab[]= "0123456789abcdef";
|
|
char *x2c;
|
|
char *p;
|
|
long i;
|
|
unsigned long u;
|
|
char temp[8 * sizeof(long) / 3 + 2];
|
|
|
|
va_list argp;
|
|
|
|
va_start(argp, fmt);
|
|
|
|
while ((c= *fmt++) != 0) {
|
|
if (c != '%') {
|
|
/* Ordinary character. */
|
|
kputc(c);
|
|
continue;
|
|
}
|
|
|
|
/* Format specifier of the form:
|
|
* %[adjust][fill][width][.max]keys
|
|
*/
|
|
c= *fmt++;
|
|
|
|
adjust= RIGHT;
|
|
if (c == '-') {
|
|
adjust= LEFT;
|
|
c= *fmt++;
|
|
}
|
|
|
|
fill= ' ';
|
|
if (c == '0') {
|
|
fill= '0';
|
|
c= *fmt++;
|
|
}
|
|
|
|
width= 0;
|
|
if (c == '*') {
|
|
/* Width is specified as an argument, e.g. %*d. */
|
|
width= va_arg(argp, int);
|
|
c= *fmt++;
|
|
} else
|
|
if (isdigit(c)) {
|
|
/* A number tells the width, e.g. %10d. */
|
|
do {
|
|
width= width * 10 + (c - '0');
|
|
} while (isdigit(c= *fmt++));
|
|
}
|
|
|
|
max= INT_MAX;
|
|
if (c == '.') {
|
|
/* Max field length coming up. */
|
|
if ((c= *fmt++) == '*') {
|
|
max= va_arg(argp, int);
|
|
c= *fmt++;
|
|
} else
|
|
if (isdigit(c)) {
|
|
max= 0;
|
|
do {
|
|
max= max * 10 + (c - '0');
|
|
} while (isdigit(c= *fmt++));
|
|
}
|
|
}
|
|
|
|
/* Set a few flags to the default. */
|
|
x2c= x2c_tab;
|
|
i= 0;
|
|
base= 10;
|
|
intsize= INT;
|
|
if (c == 'l' || c == 'L') {
|
|
/* "Long" key, e.g. %ld. */
|
|
intsize= LONG;
|
|
c= *fmt++;
|
|
}
|
|
if (c == 0) break;
|
|
|
|
switch (c) {
|
|
/* Decimal. */
|
|
case 'd':
|
|
i= intsize == LONG ? va_arg(argp, long)
|
|
: va_arg(argp, int);
|
|
u= i < 0 ? -i : i;
|
|
goto int2ascii;
|
|
|
|
/* Octal. */
|
|
case 'o':
|
|
base= 010;
|
|
goto getint;
|
|
|
|
/* Pointer, interpret as %X or %lX. */
|
|
case 'p':
|
|
if (sizeof(char *) > sizeof(int)) intsize= LONG;
|
|
|
|
/* Hexadecimal. %X prints upper case A-F, not %lx. */
|
|
case 'X':
|
|
x2c= X2C_tab;
|
|
case 'x':
|
|
base= 0x10;
|
|
goto getint;
|
|
|
|
/* Unsigned decimal. */
|
|
case 'u':
|
|
getint:
|
|
u= intsize == LONG ? va_arg(argp, unsigned long)
|
|
: va_arg(argp, unsigned int);
|
|
int2ascii:
|
|
p= temp + sizeof(temp)-1;
|
|
*p= 0;
|
|
do {
|
|
*--p= x2c[(ptrdiff_t) (u % base)];
|
|
} while ((u /= base) > 0);
|
|
goto string_length;
|
|
|
|
/* A character. */
|
|
case 'c':
|
|
p= temp;
|
|
*p= va_arg(argp, int);
|
|
len= 1;
|
|
goto string_print;
|
|
|
|
/* Simply a percent. */
|
|
case '%':
|
|
p= temp;
|
|
*p= '%';
|
|
len= 1;
|
|
goto string_print;
|
|
|
|
/* A string. The other cases will join in here. */
|
|
case 's':
|
|
p= va_arg(argp, char *);
|
|
|
|
string_length:
|
|
for (len= 0; p[len] != 0 && len < max; len++) {}
|
|
|
|
string_print:
|
|
width -= len;
|
|
if (i < 0) width--;
|
|
if (fill == '0' && i < 0) kputc('-');
|
|
if (adjust == RIGHT) {
|
|
while (width > 0) { kputc(fill); width--; }
|
|
}
|
|
if (fill == ' ' && i < 0) kputc('-');
|
|
while (len > 0) { kputc((unsigned char) *p++); len--; }
|
|
while (width > 0) { kputc(fill); width--; }
|
|
break;
|
|
|
|
/* Unrecognized format key, echo it back. */
|
|
default:
|
|
kputc('%');
|
|
kputc(c);
|
|
}
|
|
}
|
|
|
|
/* Mark the end with a null (should be something else, like -1). */
|
|
kputc(0);
|
|
va_end(argp);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* $PchId: kprintf.c,v 1.5 1996/04/11 06:59:05 philip Exp $
|
|
*/
|