xref: /netbsd-src/libexec/ld.elf_so/xprintf.c (revision 6cf6fe02a981b55727c49c3d37b0d8191a98c0ee) 
1 /*	$NetBSD: xprintf.c,v 1.21 2010/12/16 22:52:32 joerg Exp $	 */
2 
3 /*
4  * Copyright 1996 Matt Thomas <matt@3am-software.com>
5  * 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. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 #ifndef lint
32 __RCSID("$NetBSD: xprintf.c,v 1.21 2010/12/16 22:52:32 joerg Exp $");
33 #endif /* not lint */
34 
35 #include <string.h>
36 #include <stdlib.h>
37 #include <unistd.h>
38 #include <errno.h>
39 #include <stdarg.h>
40 
41 #include "rtldenv.h"
42 
43 #ifdef RTLD_LOADER
44 #define	SZ_LONG		0x01
45 #define	SZ_UNSIGNED	0x02
46 #define SZ_SIZE_T	0x04
47 
48 /*
49  * Non-mallocing printf, for use by malloc and rtld itself.
50  * This avoids putting in most of stdio.
51  *
52  * deals withs formats %x, %p, %s, and %d.
53  */
54 size_t
55 xvsnprintf(char *buf, size_t buflen, const char *fmt, va_list ap)
56 {
57 	char *bp = buf;
58 	char *const ep = buf + buflen - 4;
59 	int size, prec;
60 
61 	while (*fmt != '\0' && bp < ep) {
62 		switch (*fmt) {
63 		case '\\':{
64 			if (fmt[1] != '\0')
65 				*bp++ = *++fmt;
66 			continue;
67 		}
68 		case '%':{
69 			size = 0;
70 			prec = -1;
71 	rflag:		switch (fmt[1]) {
72 			case '*':
73 				prec = va_arg(ap, int);
74 				/* FALLTHROUGH */
75 			case '.':
76 				fmt++;
77 				goto rflag;
78 			case 'l':
79 				size |= SZ_LONG;
80 				fmt++;
81 				goto rflag;
82 			case 'z':
83 				size |= SZ_SIZE_T;
84 				fmt++;
85 				goto rflag;
86 			case 'u':
87 				size |= SZ_UNSIGNED;
88 				/* FALLTHROUGH */
89 			case 'd':{
90 				long sval;
91 				unsigned long uval;
92 				char digits[sizeof(int) * 3], *dp = digits;
93 #define	SARG() \
94 (size & SZ_LONG ? va_arg(ap, long) : \
95 ((size & SZ_SIZE_T ? (long)va_arg(ap, size_t) : \
96 va_arg(ap, int))))
97 #define	UARG() \
98 (size & SZ_LONG ? va_arg(ap, unsigned long) : \
99 ((size & SZ_SIZE_T ? va_arg(ap, size_t) : \
100 va_arg(ap, unsigned int))))
101 
102 				if (fmt[1] == 'd') {
103 					if (size & SZ_UNSIGNED)
104 						sval = UARG();
105 					else
106 						sval = SARG();
107 					if (sval < 0) {
108 						if ((sval << 1) == 0) {
109 							/*
110 							 * We can't flip the
111 							 * sign of this since
112 							 * it can't be
113 							 * represented as a
114 							 * positive number in
115 							 * two complement,
116 							 * handle the first
117 							 * digit. After that,
118 							 * it can be flipped
119 							 * since it is now not
120 							 * 2^(n-1).
121 							 */
122 							*dp++ = '0'-(sval % 10);
123 							sval /= 10;
124 						}
125 						*bp++ = '-';
126 						uval = -sval;
127 					} else {
128 						uval = sval;
129 					}
130 				} else {
131 					if (size & SZ_UNSIGNED)
132 						uval = UARG();
133 					else
134 						uval = SARG();
135 				}
136 				do {
137 					*dp++ = '0' + (uval % 10);
138 					uval /= 10;
139 				} while (uval != 0);
140 				do {
141 					*bp++ = *--dp;
142 				} while (dp != digits && bp < ep);
143 				fmt += 2;
144 				break;
145 			}
146 			case 'x':
147 			case 'p':{
148 				unsigned long val = va_arg(ap, unsigned long);
149 				unsigned long mask = ~(~0UL >> 4);
150 				int bits = sizeof(val) * 8 - 4;
151 				const char hexdigits[] = "0123456789abcdef";
152 				if (fmt[1] == 'p') {
153 					*bp++ = '0';
154 					*bp++ = 'x';
155 				}
156 				/* handle the border case */
157 				if (val == 0) {
158 					*bp++ = '0';
159 					fmt += 2;
160 					break;
161 				}
162 				/* suppress 0s */
163 				while ((val & mask) == 0)
164 					bits -= 4, mask >>= 4;
165 
166 				/* emit the hex digits */
167 				while (bits >= 0 && bp < ep) {
168 					*bp++ = hexdigits[(val & mask) >> bits];
169 					bits -= 4, mask >>= 4;
170 				}
171 				fmt += 2;
172 				break;
173 			}
174 			case 's':{
175 				const char *str = va_arg(ap, const char *);
176 				int len;
177 
178 				if (str == NULL)
179 					str = "(null)";
180 
181 				if (prec < 0)
182 					len = strlen(str);
183 				else
184 					len = prec;
185 				if (ep - bp < len)
186 					len = ep - bp;
187 				memcpy(bp, str, len);
188 				bp += len;
189 				fmt += 2;
190 				break;
191 			}
192 			case 'c':{
193 				int c = va_arg(ap, int);
194 				*bp++ = (char)c;
195 				fmt += 2;
196 				break;
197 			}
198 			default:
199 				*bp++ = *fmt;
200 				break;
201 			}
202 			break;
203 		}
204 		default:
205 			*bp++ = *fmt++;
206 			break;
207 		}
208 	}
209 
210 	*bp = '\0';
211 	return bp - buf;
212 }
213 
214 void
215 xvprintf(const char *fmt, va_list ap)
216 {
217 	char buf[256];
218 
219 	(void) write(2, buf, xvsnprintf(buf, sizeof(buf), fmt, ap));
220 }
221 
222 void
223 xprintf(const char *fmt, ...)
224 {
225 	va_list ap;
226 
227 	va_start(ap, fmt);
228 
229 	xvprintf(fmt, ap);
230 
231 	va_end(ap);
232 }
233 
234 void
235 xsnprintf(char *buf, size_t buflen, const char *fmt, ...)
236 {
237 	va_list ap;
238 
239 	va_start(ap, fmt);
240 
241 	xvsnprintf(buf, buflen, fmt, ap);
242 
243 	va_end(ap);
244 }
245 
246 #include "errlist_concat.h"
247 
248 const char *
249 xstrerror(int error)
250 {
251 
252 	if (error >= concat_nerr || error < 0) {
253 		static char buf[128];
254 		xsnprintf(buf, sizeof(buf), "Unknown error: %d", error);
255 		return buf;
256 	}
257 	return concat_errlist + concat_offset[error];
258 }
259 
260 void
261 xerrx(int eval, const char *fmt, ...)
262 {
263 	va_list ap;
264 
265 	va_start(ap, fmt);
266 	xvprintf(fmt, ap);
267 	va_end(ap);
268 	(void) write(2, "\n", 1);
269 
270 	exit(eval);
271 }
272 
273 void
274 xerr(int eval, const char *fmt, ...)
275 {
276 	int saved_errno = errno;
277 	va_list ap;
278 
279 	va_start(ap, fmt);
280 	xvprintf(fmt, ap);
281 	va_end(ap);
282 
283 	xprintf(": %s\n", xstrerror(saved_errno));
284 	exit(eval);
285 }
286 
287 void
288 xwarn(const char *fmt, ...)
289 {
290 	int saved_errno = errno;
291 	va_list ap;
292 
293 	va_start(ap, fmt);
294 	xvprintf(fmt, ap);
295 	va_end(ap);
296 
297 	xprintf(": %s\n", xstrerror(saved_errno));
298 	errno = saved_errno;
299 }
300 
301 void
302 xwarnx(const char *fmt, ...)
303 {
304 	va_list ap;
305 
306 	va_start(ap, fmt);
307 	xvprintf(fmt, ap);
308 	va_end(ap);
309 	(void) write(2, "\n", 1);
310 }
311 
312 #ifdef DEBUG
313 void
314 xassert(const char *file, int line, const char *failedexpr)
315 {
316 
317 	xprintf("assertion \"%s\" failed: file \"%s\", line %d\n",
318 		failedexpr, file, line);
319 	abort();
320 	/* NOTREACHED */
321 }
322 #endif
323 #endif
324