xref: /netbsd-src/sys/lib/libsa/subr_prf.c (revision 5e4c038a45edbc7d63b7c2daa76e29f88b64a4e3)
1 /*	$NetBSD: subr_prf.c,v 1.5 2002/02/17 23:19:00 thorpej 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)printf.c	8.1 (Berkeley) 6/11/93
36  */
37 
38 /*
39  * Scaled down version of printf(3).
40  *
41  * One additional format:
42  *
43  * The format %b is supported to decode error registers.
44  * Its usage is:
45  *
46  *	printf("reg=%b\n", regval, "<base><arg>*");
47  *
48  * where <base> is the output base expressed as a control character, e.g.
49  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
50  * the first of which gives the bit number to be inspected (origin 1), and
51  * the next characters (up to a control character, i.e. a character <= 32),
52  * give the name of the register.  Thus:
53  *
54  *	printf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
55  *
56  * would produce output:
57  *
58  *	reg=3<BITTWO,BITONE>
59  */
60 
61 #include <sys/cdefs.h>
62 #include <sys/types.h>
63 #ifdef __STDC__
64 #include <machine/stdarg.h>
65 #else
66 #include <machine/varargs.h>
67 #endif
68 
69 #include "stand.h"
70 
71 static void kprintn __P((void (*)(int), u_long, int));
72 static void sputchar __P((int));
73 static void kdoprnt __P((void (*)(int), const char *, va_list));
74 
75 static char *sbuf, *ebuf;
76 
77 static void
78 sputchar(c)
79 	int c;
80 {
81 	if (sbuf < ebuf)
82 		*sbuf++ = c;
83 }
84 
85 void
86 vprintf(const char *fmt, va_list ap)
87 {
88 
89 	kdoprnt(putchar, fmt, ap);
90 }
91 
92 int
93 vsnprintf(char *buf, size_t size, const char *fmt, va_list ap)
94 {
95 
96 	sbuf = buf;
97 	ebuf = buf + size - 1;
98 	kdoprnt(sputchar, fmt, ap);
99 	*sbuf = '\0';
100 	return (sbuf - buf);
101 }
102 
103 static void
104 kdoprnt(put, fmt, ap)
105 	void (*put)__P((int));
106 	const char *fmt;
107 	va_list ap;
108 {
109 	char *p;
110 	int ch, n;
111 	unsigned long ul;
112 	int lflag, set;
113 
114 	for (;;) {
115 		while ((ch = *fmt++) != '%') {
116 			if (ch == '\0')
117 				return;
118 			put(ch);
119 		}
120 		lflag = 0;
121 reswitch:	switch (ch = *fmt++) {
122 		case '\0':
123 			/* XXX print the last format character? */
124 			return;
125 		case 'l':
126 			lflag = 1;
127 			goto reswitch;
128 		case 'b':
129 			ul = va_arg(ap, int);
130 			p = va_arg(ap, char *);
131 			kprintn(put, ul, *p++);
132 
133 			if (!ul)
134 				break;
135 
136 			for (set = 0; (n = *p++);) {
137 				if (ul & (1 << (n - 1))) {
138 					put(set ? ',' : '<');
139 					for (; (n = *p) > ' '; ++p)
140 						put(n);
141 					set = 1;
142 				} else
143 					for (; *p > ' '; ++p);
144 			}
145 			if (set)
146 				put('>');
147 			break;
148 		case 'c':
149 			ch = va_arg(ap, int);
150 				put(ch & 0x7f);
151 			break;
152 		case 's':
153 			p = va_arg(ap, char *);
154 			while ((ch = *p++))
155 				put(ch);
156 			break;
157 		case 'd':
158 			ul = lflag ?
159 			    va_arg(ap, long) : va_arg(ap, int);
160 			if ((long)ul < 0) {
161 				put('-');
162 				ul = -(long)ul;
163 			}
164 			kprintn(put, ul, 10);
165 			break;
166 		case 'o':
167 			ul = lflag ?
168 			    va_arg(ap, u_long) : va_arg(ap, u_int);
169 			kprintn(put, ul, 8);
170 			break;
171 		case 'u':
172 			ul = lflag ?
173 			    va_arg(ap, u_long) : va_arg(ap, u_int);
174 			kprintn(put, ul, 10);
175 			break;
176 		case 'p':
177 			put('0');
178 			put('x');
179 			lflag = 1;
180 			/* fall through */
181 		case 'x':
182 			ul = lflag ?
183 			    va_arg(ap, u_long) : va_arg(ap, u_int);
184 			kprintn(put, ul, 16);
185 			break;
186 		default:
187 			put('%');
188 			if (lflag)
189 				put('l');
190 			put(ch);
191 		}
192 	}
193 }
194 
195 static void
196 kprintn(put, ul, base)
197 	void (*put)__P((int));
198 	unsigned long ul;
199 	int base;
200 {
201 					/* hold a long in base 8 */
202 	char *p, buf[(sizeof(long) * NBBY / 3) + 1];
203 
204 	p = buf;
205 	do {
206 		*p++ = "0123456789abcdef"[ul % base];
207 	} while (ul /= base);
208 	do {
209 		put(*--p);
210 	} while (p > buf);
211 }
212