1 /* libunwind - a platform-independent unwind library
2 Copyright (C) 2010, 2011 by FERMI NATIONAL ACCELERATOR LABORATORY
4 Permission is hereby granted, free of charge, to any person obtaining
5 a copy of this software and associated documentation files (the
6 "Software"), to deal in the Software without restriction, including
7 without limitation the rights to use, copy, modify, merge, publish,
8 distribute, sublicense, and/or sell copies of the Software, and to
9 permit persons to whom the Software is furnished to do so, subject to
10 the following conditions:
12 The above copyright notice and this permission notice shall be
13 included in all copies or substantial portions of the Software.
15 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
19 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
20 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
21 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
31 # include <execinfo.h>
33 extern int backtrace (void **, int);
41 #include <libunwind.h>
43 #define panic(args...) \
44 { fprintf (stderr, args); exit (-1); }
46 #define SIG_STACK_SIZE 0x100000
51 /* These variables are global because they
52 * cause the signal stack to overflow */
53 char buf[512], name[256];
54 void *addresses[3][128];
62 int ret = -UNW_ENOINFO;
67 printf ("\tnormal trace:\n");
70 if (unw_init_local (&cursor, &uc) < 0)
71 panic ("unw_init_local failed!\n");
75 unw_get_reg (&cursor, UNW_REG_IP, &ip);
76 addresses[0][depth] = (void *) ip;
78 while ((ret = unw_step (&cursor)) > 0 && ++depth < 128);
82 unw_get_reg (&cursor, UNW_REG_IP, &ip);
83 printf ("FAILURE: unw_step() returned %d for ip=%lx\n", ret, (long) ip);
88 for (i = 0; i < depth; ++i)
89 printf ("\t #%-3d ip=%p\n", i, addresses[0][i]);
92 printf ("\n\tvia backtrace():\n");
94 n = backtrace (addresses[1], 128);
97 for (i = 0; i < n; ++i)
98 printf ("\t #%-3d ip=%p\n", i, addresses[1][i]);
101 printf ("\n\tvia unw_backtrace():\n");
103 m = unw_backtrace (addresses[2], 128);
106 for (i = 0; i < m; ++i)
107 printf ("\t #%-3d ip=%p\n", i, addresses[2][i]);
111 printf ("FAILURE: unw_step() loop and unw_backtrace() depths differ: %d vs. %d\n", depth, m);
117 printf ("FAILURE: unw_step() loop and backtrace() depths differ: %d vs. %d\n", depth, n);
122 for (i = 1; i < n; ++i)
123 /* Allow one in difference in comparison, trace returns adjusted addresses. */
124 if (labs((unw_word_t) addresses[1][i] - (unw_word_t) addresses[2][i]) > 1)
126 printf ("FAILURE: backtrace() and unw_backtrace() addresses differ at %d: %p vs. %p\n",
127 i, addresses[1][i], addresses[2][i]);
132 for (i = 1; i < depth; ++i)
133 /* Allow one in difference in comparison, trace returns adjusted addresses. */
134 if (labs((unw_word_t) addresses[0][i] - (unw_word_t) addresses[1][i]) > 1)
136 printf ("FAILURE: unw_step() loop and backtrace() addresses differ at %d: %p vs. %p\n",
137 i, addresses[0][i], addresses[1][i]);
143 foo (long val UNUSED)
151 extern long f (long);
154 /* This is a vain attempt to use up lots of registers to force
155 the frame-chain info to be saved on the memory stack on ia64.
156 It happens to work with gcc v3.3.4 and gcc v3.4.1 but perhaps
157 not with any other compiler. */
158 foo (f (arr[0]) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
159 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
160 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
161 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
162 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
163 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
164 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
165 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
166 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
167 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
168 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
169 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
170 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
171 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
172 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
173 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v)
174 + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + (f (v) + f (v))
175 ))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))
176 )))))))))))))))))))))))))))))))))))))))))))))))))))))));
180 sighandler (int signal, void *siginfo UNUSED, void *context)
182 ucontext_t *uc UNUSED;
189 printf ("sighandler: got signal %d, sp=%p", signal, &sp);
191 # if defined(__linux__)
192 printf (" @ %lx", uc->uc_mcontext.sc_ip);
198 __uc_get_reason (uc, &reason);
199 __uc_get_ip (uc, &ip);
200 printf (" @ %lx (reason=%d)", ip, reason);
204 #if defined __linux__
205 printf (" @ %lx", (unsigned long) uc->uc_mcontext.gregs[REG_EIP]);
206 #elif defined __FreeBSD__
207 printf (" @ %lx", (unsigned long) uc->uc_mcontext.mc_eip);
209 #elif UNW_TARGET_X86_64
210 #if defined __linux__
211 printf (" @ %lx", (unsigned long) uc->uc_mcontext.gregs[REG_RIP]);
212 #elif defined __FreeBSD__
213 printf (" @ %lx", (unsigned long) uc->uc_mcontext.mc_rip);
215 #elif defined UNW_TARGET_ARM
216 #if defined __linux__
217 printf (" @ %lx", (unsigned long) uc->uc_mcontext.arm_pc);
218 #elif defined __FreeBSD__
219 printf (" @ %lx", (unsigned long) uc->uc_mcontext.__gregs[_REG_PC]);
228 main (int argc, char **argv UNUSED)
230 struct sigaction act;
233 verbose = (argc > 1);
236 printf ("Normal backtrace:\n");
240 memset (&act, 0, sizeof (act));
241 act.sa_handler = (void (*)(int)) sighandler;
242 act.sa_flags = SA_SIGINFO;
243 if (sigaction (SIGTERM, &act, NULL) < 0)
244 panic ("sigaction: %s\n", strerror (errno));
247 printf ("\nBacktrace across signal handler:\n");
248 kill (getpid (), SIGTERM);
251 printf ("\nBacktrace across signal handler on alternate stack:\n");
252 stk.ss_sp = malloc (SIG_STACK_SIZE);
254 panic ("failed to allocate %u bytes\n", SIG_STACK_SIZE);
255 stk.ss_size = SIG_STACK_SIZE;
257 if (sigaltstack (&stk, NULL) < 0)
258 panic ("sigaltstack: %s\n", strerror (errno));
260 memset (&act, 0, sizeof (act));
261 act.sa_handler = (void (*)(int)) sighandler;
262 act.sa_flags = SA_ONSTACK | SA_SIGINFO;
263 if (sigaction (SIGTERM, &act, NULL) < 0)
264 panic ("sigaction: %s\n", strerror (errno));
265 kill (getpid (), SIGTERM);
269 fprintf (stderr, "FAILURE: detected %d errors\n", num_errors);
274 printf ("SUCCESS.\n");
276 signal (SIGTERM, SIG_DFL);
277 stk.ss_flags = SS_DISABLE;
278 sigaltstack (&stk, NULL);