xref: /openbsd/libexec/ld.so/dl_printf.c (revision db3296cf)
1 /*	$OpenBSD: dl_printf.c,v 1.13 2003/07/06 20:03:57 deraadt 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  * One additional format:
38  *
39  * The format %b is supported to decode error registers.
40  * Its usage is:
41  *
42  *	printf("reg=%b\n", regval, "<base><arg>*");
43  *
44  * where <base> is the output base expressed as a control character, e.g.
45  * \10 gives octal; \20 gives hex.  Each arg is a sequence of characters,
46  * the first of which gives the bit number to be inspected (origin 1), and
47  * the next characters (up to a control character, i.e. a character <= 32),
48  * give the name of the register.  Thus:
49  *
50  *	printf("reg=%b\n", 3, "\10\2BITTWO\1BITONE\n");
51  *
52  * would produce output:
53  *
54  *	reg=3<BITTWO,BITONE>
55  */
56 
57 #include <sys/cdefs.h>
58 #include <sys/types.h>
59 #include <stdarg.h>
60 #include "syscall.h"
61 #include "util.h"
62 
63 static void kprintn(void (*)(int,int), int, u_long, int);
64 static void kdoprnt(void (*)(int,int), int, const char *, va_list);
65 
66 static void putcharfd(int, int );
67 
68 static void
69 putcharfd(int c, int fd)
70 {
71 	char b = c;
72 
73 	_dl_write(fd, &b, 1);
74 }
75 
76 void
77 _dl_printf(const char *fmt, ...)
78 {
79 	va_list ap;
80 
81 	va_start(ap, fmt);
82 	kdoprnt(putcharfd, 2, fmt, ap);
83 	va_end(ap);
84 }
85 
86 void
87 _dl_fdprintf(int fd, const char *fmt, ...)
88 {
89 	va_list ap;
90 
91 	va_start(ap, fmt);
92 	kdoprnt(putcharfd, fd, fmt, ap);
93 	va_end(ap);
94 }
95 
96 void
97 _dl_vprintf(const char *fmt, va_list ap)
98 {
99 	kdoprnt(putcharfd, 2, fmt, ap);
100 }
101 
102 static void
103 kdoprnt(void (*put)(int,int), int fd, const char *fmt, va_list ap)
104 {
105 	unsigned long ul;
106 	int lflag, ch;
107 	char *p;
108 
109 	for (;;) {
110 		while ((ch = *fmt++) != '%') {
111 			if (ch == '\0')
112 				return;
113 			put(ch, fd);
114 		}
115 		lflag = 0;
116 reswitch:
117 		switch (ch = *fmt++) {
118 		case 'l':
119 			lflag = 1;
120 			goto reswitch;
121 		case 'b':
122 		{
123 			int set, n;
124 
125 			ul = va_arg(ap, int);
126 			p = va_arg(ap, char *);
127 			kprintn(put, fd, ul, *p++);
128 
129 			if (!ul)
130 				break;
131 
132 			for (set = 0; (n = *p++);) {
133 				if (ul & (1 << (n - 1))) {
134 					put(set ? ',' : '<', fd);
135 					for (; (n = *p) > ' '; ++p)
136 						put(n, fd);
137 					set = 1;
138 				} else
139 					for (; *p > ' '; ++p);
140 			}
141 			if (set)
142 				put('>', fd);
143 		}
144 			break;
145 		case 'c':
146 			ch = va_arg(ap, int);
147 			put(ch & 0x7f, fd);
148 			break;
149 		case 's':
150 			p = va_arg(ap, char *);
151 			while ((ch = *p++))
152 				put(ch, fd);
153 			break;
154 		case 'd':
155 			ul = lflag ? va_arg(ap, long) : va_arg(ap, int);
156 			if ((long)ul < 0) {
157 				put('-', fd);
158 				ul = -(long)ul;
159 			}
160 			kprintn(put, fd, ul, 10);
161 			break;
162 		case 'o':
163 			ul = lflag ? va_arg(ap, u_long) : va_arg(ap, u_int);
164 			kprintn(put, fd, ul, 8);
165 			break;
166 		case 'u':
167 			ul = lflag ? va_arg(ap, u_long) : va_arg(ap, u_int);
168 			kprintn(put, fd, ul, 10);
169 			break;
170 		case 'p':
171 			put('0', fd);
172 			put('x', fd);
173 			lflag += sizeof(void *)==sizeof(u_long)? 1 : 0;
174 		case 'x':
175 			ul = lflag ? va_arg(ap, u_long) : va_arg(ap, u_int);
176 			kprintn(put, fd, ul, 16);
177 			break;
178 		case 'X':
179 		{
180 			int l;
181 
182 			ul = lflag ? va_arg(ap, u_long) : va_arg(ap, u_int);
183 			if (lflag)
184 				l = (sizeof(ulong) * 8) - 4;
185 			else
186 				l = (sizeof(u_int) * 8) - 4;
187 			while (l >= 0) {
188 				put("0123456789abcdef"[(ul >> l) & 0xf], fd);
189 				l -= 4;
190 			}
191 			break;
192 		}
193 		default:
194 			put('%', fd);
195 			if (lflag)
196 				put('l', fd);
197 			put(ch, fd);
198 		}
199 	}
200 	va_end(ap);
201 }
202 
203 static void
204 kprintn(void (*put)(int,int), int fd, unsigned long ul, int base)
205 {
206 	/* hold a long in base 8 */
207 	char *p, buf[(sizeof(long) * NBBY / 3) + 1];
208 
209 	p = buf;
210 	do {
211 		*p++ = "0123456789abcdef"[ul % base];
212 	} while (ul /= base);
213 	do {
214 		put(*--p, fd);
215 	} while (p > buf);
216 }
217