xref: /illumos-gate/usr/src/lib/libumem/common/misc.c (revision 5422785d352a2bb398daceab3d1898a8aa64d006)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <unistd.h>
30 #include <dlfcn.h>
31 #include <signal.h>
32 #include <stdarg.h>
33 #include <stdio.h>
34 #include <string.h>
35 
36 #include <sys/machelf.h>
37 
38 #include <umem_impl.h>
39 #include "misc.h"
40 
41 #define	UMEM_ERRFD	2	/* goes to standard error */
42 #define	UMEM_MAX_ERROR_SIZE 4096 /* error messages are truncated to this */
43 
44 /*
45  * This is a circular buffer for holding error messages.
46  * umem_error_enter appends to the buffer, adding "..." to the beginning
47  * if data has been lost.
48  */
49 
50 #define	ERR_SIZE 8192		/* must be a power of 2 */
51 
52 static mutex_t umem_error_lock = DEFAULTMUTEX;
53 
54 static char umem_error_buffer[ERR_SIZE] = "";
55 static uint_t umem_error_begin = 0;
56 static uint_t umem_error_end = 0;
57 
58 #define	WRITE_AND_INC(var, value) { \
59 	umem_error_buffer[(var)++] = (value); \
60 	var = P2PHASE((var), ERR_SIZE); \
61 }
62 
63 static void
64 umem_log_enter(const char *error_str)
65 {
66 	int looped;
67 	char c;
68 
69 	looped = 0;
70 
71 	(void) mutex_lock(&umem_error_lock);
72 
73 	while ((c = *error_str++) != '\0') {
74 		WRITE_AND_INC(umem_error_end, c);
75 		if (umem_error_end == umem_error_begin)
76 			looped = 1;
77 	}
78 
79 	umem_error_buffer[umem_error_end] = 0;
80 
81 	if (looped) {
82 		uint_t idx;
83 		umem_error_begin = P2PHASE(umem_error_end + 1, ERR_SIZE);
84 
85 		idx = umem_error_begin;
86 		WRITE_AND_INC(idx, '.');
87 		WRITE_AND_INC(idx, '.');
88 		WRITE_AND_INC(idx, '.');
89 	}
90 
91 	(void) mutex_unlock(&umem_error_lock);
92 }
93 
94 void
95 umem_error_enter(const char *error_str)
96 {
97 #ifndef UMEM_STANDALONE
98 	if (umem_output && !issetugid())
99 		(void) write(UMEM_ERRFD, error_str, strlen(error_str));
100 #endif
101 
102 	umem_log_enter(error_str);
103 }
104 
105 int
106 highbit(ulong_t i)
107 {
108 	register int h = 1;
109 
110 	if (i == 0)
111 		return (0);
112 #ifdef _LP64
113 	if (i & 0xffffffff00000000ul) {
114 		h += 32; i >>= 32;
115 	}
116 #endif
117 	if (i & 0xffff0000) {
118 		h += 16; i >>= 16;
119 	}
120 	if (i & 0xff00) {
121 		h += 8; i >>= 8;
122 	}
123 	if (i & 0xf0) {
124 		h += 4; i >>= 4;
125 	}
126 	if (i & 0xc) {
127 		h += 2; i >>= 2;
128 	}
129 	if (i & 0x2) {
130 		h += 1;
131 	}
132 	return (h);
133 }
134 
135 int
136 lowbit(ulong_t i)
137 {
138 	register int h = 1;
139 
140 	if (i == 0)
141 		return (0);
142 #ifdef _LP64
143 	if (!(i & 0xffffffff)) {
144 		h += 32; i >>= 32;
145 	}
146 #endif
147 	if (!(i & 0xffff)) {
148 		h += 16; i >>= 16;
149 	}
150 	if (!(i & 0xff)) {
151 		h += 8; i >>= 8;
152 	}
153 	if (!(i & 0xf)) {
154 		h += 4; i >>= 4;
155 	}
156 	if (!(i & 0x3)) {
157 		h += 2; i >>= 2;
158 	}
159 	if (!(i & 0x1)) {
160 		h += 1;
161 	}
162 	return (h);
163 }
164 
165 void
166 hrt2ts(hrtime_t hrt, timestruc_t *tsp)
167 {
168 	tsp->tv_sec = hrt / NANOSEC;
169 	tsp->tv_nsec = hrt % NANOSEC;
170 }
171 
172 void
173 log_message(const char *format, ...)
174 {
175 	char buf[UMEM_MAX_ERROR_SIZE] = "";
176 
177 	va_list va;
178 
179 	va_start(va, format);
180 	(void) vsnprintf(buf, UMEM_MAX_ERROR_SIZE-1, format, va);
181 	va_end(va);
182 
183 #ifndef UMEM_STANDALONE
184 	if (umem_output > 1)
185 		(void) write(UMEM_ERRFD, buf, strlen(buf));
186 #endif
187 
188 	umem_log_enter(buf);
189 }
190 
191 #ifndef UMEM_STANDALONE
192 void
193 debug_printf(const char *format, ...)
194 {
195 	char buf[UMEM_MAX_ERROR_SIZE] = "";
196 
197 	va_list va;
198 
199 	va_start(va, format);
200 	(void) vsnprintf(buf, UMEM_MAX_ERROR_SIZE-1, format, va);
201 	va_end(va);
202 
203 	(void) write(UMEM_ERRFD, buf, strlen(buf));
204 }
205 #endif
206 
207 void
208 umem_vprintf(const char *format, va_list va)
209 {
210 	char buf[UMEM_MAX_ERROR_SIZE] = "";
211 
212 	(void) vsnprintf(buf, UMEM_MAX_ERROR_SIZE-1, format, va);
213 
214 	umem_error_enter(buf);
215 }
216 
217 void
218 umem_printf(const char *format, ...)
219 {
220 	va_list va;
221 
222 	va_start(va, format);
223 	umem_vprintf(format, va);
224 	va_end(va);
225 }
226 
227 /*ARGSUSED*/
228 void
229 umem_printf_warn(void *ignored, const char *format, ...)
230 {
231 	va_list va;
232 
233 	va_start(va, format);
234 	umem_vprintf(format, va);
235 	va_end(va);
236 }
237 
238 /*
239  * print_sym tries to print out the symbol and offset of a pointer
240  */
241 int
242 print_sym(void *pointer)
243 {
244 	int result;
245 	Dl_info sym_info;
246 
247 	uintptr_t end = NULL;
248 
249 	Sym *ext_info = NULL;
250 
251 	result = dladdr1(pointer, &sym_info, (void **)&ext_info,
252 	    RTLD_DL_SYMENT);
253 
254 	if (result != 0) {
255 		const char *endpath;
256 
257 		end = (uintptr_t)sym_info.dli_saddr + ext_info->st_size;
258 
259 		endpath = strrchr(sym_info.dli_fname, '/');
260 		if (endpath)
261 			endpath++;
262 		else
263 			endpath = sym_info.dli_fname;
264 		umem_printf("%s'", endpath);
265 	}
266 
267 	if (result == 0 || (uintptr_t)pointer > end) {
268 		umem_printf("?? (0x%p)", pointer);
269 		return (0);
270 	} else {
271 		umem_printf("%s+0x%p", sym_info.dli_sname,
272 		    (char *)pointer - (char *)sym_info.dli_saddr);
273 		return (1);
274 	}
275 }
276