/*
 * Copyright (c) 1982, 1986 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 *
 *	@(#)prf.c	7.5 (Berkeley) 6/6/88
 */


/*
 * Scaled down version of C Library printf.
 * Used to print diagnostic information directly on console tty.
 * Since it is not interrupt driven, all system activities are
 * suspended.  Printf should not be used for chit-chat.
 *
 * One additional format: %b is supported to decode error registers.
 * 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=2<BITTWO,BITONE>
 */
/*VARARGS1*/
printf(fmt, x1)
	char *fmt;
	unsigned x1;
{

	prf(fmt, &x1);
}

prf(fmt, adx)
	register char *fmt;
	register unsigned int *adx;
{
	register int b, c, i;
	char *s, padc;
	int any, pad;

loop:
	while ((c = *fmt++) != '%') {
		if(c == '\0')
			return;
		putchar(c);
	}
	pad = 0;
	padc = ' ';
again:
	c = *fmt++;
	/* THIS CODE IS VAX DEPENDENT IN HANDLING %l? AND %c */
	switch (c) {

	case 'l':
		goto again;
	case 'x': case 'X':
		b = 16;
		goto number;
	case 'd': case 'D':
	case 'u':		/* what a joke */
		b = 10;
		goto number;
	case 'o': case 'O':
		b = 8;
number:
		printn((unsigned long)*adx, b, pad, padc);
		break;
	case 'c':
		b = *adx;
		for (i = 24; i >= 0; i -= 8)
			if (c = (b >> i) & 0x7f)
				putchar(c);
		break;
	case 'b':
		b = *adx++;
		s = (char *)*adx;
		printn((unsigned long)b, *s++, 0, 0);
		any = 0;
		if (b) {
			while (i = *s++) {
				if (b & (1 << (i-1))) {
					putchar(any? ',' : '<');
					any = 1;
					for (; (c = *s) > 32; s++)
						putchar(c);
				} else
					for (; *s > 32; s++)
						;
			}
			if (any)
				putchar('>');
		}
		break;

	case 's':
		s = (char *)*adx;
		if (s == 0)
		  s = "(null)";
		while (c = *s++)
			putchar(c);
		break;
	case '0':
		if (!pad)
		  padc = '0';
		/* fall through to */
	case '1':
	case '2':
	case '3':
	case '4':
	case '5':
	case '6':
	case '7':
	case '8':
	case '9':
		pad = pad * 10 + (c - '0');
		goto again;
	}
	adx++;
	goto loop;
}


/*
 * Printn prints a number n in base b.  If p, the it pre-pads a field that
 * long with character c.
 * We don't use recursion to avoid deep kernel stacks.
 */
printn(n, b, p, c)
	unsigned long n;
	int b, p;
	char c;
{
	register char *cp;
	char prbuf[11];

	cp = prbuf;
	do {
		*cp++ = "0123456789abcdef"[n%b];
		n /= b;
	} while (n);
	if (p) {
	    p -= cp - prbuf;
	    if (b == 10 && (int)n < 0)
	      p--;
	    while (p-- > 0)
	      putchar(c);
	}
	if (b == 10 && (int)n < 0) {
		putchar('-');
		n = (unsigned)(-(int)n);
	}
	do
		putchar(*--cp);
	while (cp > prbuf);
}