BSD 4_2 release

[unix-history] / usr / src / sys / stand / prf.c

/*      prf.c   6.1     83/07/29        */

#include "../h/param.h"

#include "../vax/mtpr.h"
#include "../vax/cons.h"

/*
* 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 u_int *adx;
{
       register int b, c, i;
       char *s;
       int any;

loop:
       while ((c = *fmt++) != '%') {
               if(c == '\0')
                       return;
               putchar(c);
       }
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((u_long)*adx, b);
               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((u_long)b, *s++);
               any = 0;
               if (b) {
                       putchar('<');
                       while (i = *s++) {
                               if (b & (1 << (i-1))) {
                                       if (any)
                                               putchar(',');
                                       any = 1;
                                       for (; (c = *s) > 32; s++)
                                               putchar(c);
                               } else
                                       for (; *s > 32; s++)
                                               ;
                       }
                       putchar('>');
               }
               break;

       case 's':
               s = (char *)*adx;
               while (c = *s++)
                       putchar(c);
               break;
       }
       adx++;
       goto loop;
}

/*
* Printn prints a number n in base b.
* We don't use recursion to avoid deep kernel stacks.
*/
printn(n, b)
       u_long n;
{
       char prbuf[11];
       register char *cp;

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

/*
* Print a character on console.
* Attempts to save and restore device
* status.
*
* Whether or not printing is inhibited,
* the last MSGBUFS characters
* are saved in msgbuf for inspection later.
*/
putchar(c)
       register c;
{
       register s, timo;

       timo = 30000;
       /*
        * Try waiting for the console tty to come ready,
        * otherwise give up after a reasonable time.
        */
       while((mfpr(TXCS)&TXCS_RDY) == 0)
               if(--timo == 0)
                       break;
       if(c == 0)
               return;
       s = mfpr(TXCS);
       mtpr(TXCS,0);
       mtpr(TXDB, c&0xff);
       if(c == '\n')
               putchar('\r');
       putchar(0);
       mtpr(TXCS, s);
}

getchar()
{
       register c;

       while((mfpr(RXCS)&RXCS_DONE) == 0)
               ;
       c = mfpr(RXDB)&0177;
       if (c=='\r')
               c = '\n';
       putchar(c);
       return(c);
}

gets(buf)
       char *buf;
{
       register char *lp;
       register c;

       lp = buf;
       for (;;) {
               c = getchar() & 0177;
       store:
               switch(c) {
               case '\n':
               case '\r':
                       c = '\n';
                       *lp++ = '\0';
                       return;
               case '\b':
               case '#':
                       lp--;
                       if (lp < buf)
                               lp = buf;
                       continue;
               case '@':
               case 'u'&037:
                       lp = buf;
                       putchar('\n');
                       continue;
               default:
                       *lp++ = c;
               }
       }
}