sys/lib/libsa/subr_prf.c

   1 /*      $NetBSD: subr_prf.c,v 1.15 2006/01/27 02:28:36 uwe Exp $        */
   2
   3 /*-
   4  * Copyright (c) 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      @(#)printf.c    8.1 (Berkeley) 6/11/93
  32  */
  33
  34 /*
  35  * Scaled down version of printf(3).
  36  */
  37
  38 #include <sys/cdefs.h>
  39 #include <sys/types.h>
  40 #include <sys/stdint.h>         /* XXX: for intptr_t */
  41 #include <machine/stdarg.h>
  42
  43 #include "stand.h"
  44
  45 static void kprintn(void (*)(int), u_long, int);
  46 static void sputchar(int);
  47 static void kdoprnt(void (*)(int), const char *, va_list);
  48
  49 static char *sbuf, *ebuf;
  50
  51 const char HEXDIGITS[] = "0123456789ABCDEF";
  52 const char hexdigits[] = "0123456789abcdef";
  53
  54 static void
  55 sputchar(int c)
  56 {
  57
  58         if (sbuf < ebuf)
  59                 *sbuf++ = c;
  60 }
  61
  62 void
  63 vprintf(const char *fmt, va_list ap)
  64 {
  65
  66         kdoprnt(putchar, fmt, ap);
  67 }
  68
  69 int
  70 vsnprintf(char *buf, size_t size, const char *fmt, va_list ap)
  71 {
  72
  73         sbuf = buf;
  74         ebuf = buf + size - 1;
  75         kdoprnt(sputchar, fmt, ap);
  76         *sbuf = '\0';
  77         return sbuf - buf;
  78 }
  79
  80 static void
  81 kdoprnt(void (*put)(int), const char *fmt, va_list ap)
  82 {
  83         char *p;
  84         int ch;
  85         unsigned long ul;
  86         int lflag;
  87
  88         for (;;) {
  89                 while ((ch = *fmt++) != '%') {
  90                         if (ch == '\0')
  91                                 return;
  92                         put(ch);
  93                 }
  94                 lflag = 0;
  95 reswitch:
  96                 switch (ch = *fmt++) {
  97                 case 'l':
  98                         lflag = 1;
  99                         goto reswitch;
 100                 case 't':
 101 #if 0 /* XXX: abuse intptr_t until the situation with ptrdiff_t is clear */
 102                         lflag = (sizeof(ptrdiff_t) == sizeof(long));
 103 #else
 104                         lflag = (sizeof(intptr_t) == sizeof(long));
 105 #endif
 106                         goto reswitch;
 107                 case 'z':
 108                         lflag = (sizeof(size_t) == sizeof(unsigned long));
 109                         goto reswitch;
 110                 case 'c':
 111                         ch = va_arg(ap, int);
 112                                 put(ch & 0x7f);
 113                         break;
 114                 case 's':
 115                         p = va_arg(ap, char *);
 116                         while ((ch = *p++))
 117                                 put(ch);
 118                         break;
 119                 case 'd':
 120                         ul = lflag ?
 121                             va_arg(ap, long) : va_arg(ap, int);
 122                         if ((long)ul < 0) {
 123                                 put('-');
 124                                 ul = -(long)ul;
 125                         }
 126                         kprintn(put, ul, 10);
 127                         break;
 128                 case 'o':
 129                         ul = lflag ?
 130                             va_arg(ap, u_long) : va_arg(ap, u_int);
 131                         kprintn(put, ul, 8);
 132                         break;
 133                 case 'u':
 134                         ul = lflag ?
 135                             va_arg(ap, u_long) : va_arg(ap, u_int);
 136                         kprintn(put, ul, 10);
 137                         break;
 138                 case 'p':
 139                         put('0');
 140                         put('x');
 141                         lflag = 1;
 142                         /* FALLTHROUGH */
 143                 case 'x':
 144                         ul = lflag ?
 145                             va_arg(ap, u_long) : va_arg(ap, u_int);
 146                         kprintn(put, ul, 16);
 147                         break;
 148                 default:
 149                         put('%');
 150                         if (lflag)
 151                                 put('l');
 152                         if (ch == '\0')
 153                                 return;
 154                         put(ch);
 155                         break;
 156                 }
 157         }
 158 }
 159
 160 static void
 161 kprintn(void (*put)(int), unsigned long ul, int base)
 162 {
 163                                         /* hold a long in base 8 */
 164         char *p, buf[(sizeof(long) * NBBY / 3) + 1];
 165
 166         p = buf;
 167         do {
 168                 *p++ = hexdigits[ul % base];
 169         } while (ul /= base);
 170         do {
 171                 put(*--p);
 172         } while (p > buf);
 173 }