1 /* libunwind - a platform-independent unwind library
2 Copyright (C) 2003-2004 Hewlett-Packard Co
3 Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
4
5 This file is part of libunwind.
6
7 Permission is hereby granted, free of charge, to any person obtaining
8 a copy of this software and associated documentation files (the
9 "Software"), to deal in the Software without restriction, including
10 without limitation the rights to use, copy, modify, merge, publish,
11 distribute, sublicense, and/or sell copies of the Software, and to
12 permit persons to whom the Software is furnished to do so, subject to
13 the following conditions:
14
15 The above copyright notice and this permission notice shall be
16 included in all copies or substantial portions of the Software.
17
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
21 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
25
26 #include <config.h>
27
28 #ifdef HAVE_TTRACE
29
30 int
main(void)31 main (void)
32 {
33 printf ("FAILURE: ttrace() not supported yet\n");
34 return -1;
35 }
36
37 #else /* !HAVE_TTRACE */
38
39 #include <errno.h>
40 #include <fcntl.h>
41 #include <libunwind-ptrace.h>
42 #include <signal.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47
48 #include <sys/ptrace.h>
49 #include <sys/wait.h>
50
51 extern char **environ;
52
53 static const int nerrors_max = 100;
54
55 int nerrors;
56 int verbose;
57 int print_names = 1;
58
59 enum
60 {
61 INSTRUCTION,
62 SYSCALL,
63 TRIGGER
64 }
65 trace_mode = SYSCALL;
66
67 #define panic(args...) \
68 do { fprintf (stderr, args); ++nerrors; } while (0)
69
70 static unw_addr_space_t as;
71 static struct UPT_info *ui;
72
73 static int killed;
74
75 void
do_backtrace(void)76 do_backtrace (void)
77 {
78 unw_word_t ip, sp, start_ip = 0, off;
79 int n = 0, ret;
80 unw_proc_info_t pi;
81 unw_cursor_t c;
82 char buf[512];
83 size_t len;
84
85 ret = unw_init_remote (&c, as, ui);
86 if (ret < 0)
87 panic ("unw_init_remote() failed: ret=%d\n", ret);
88
89 do
90 {
91 if ((ret = unw_get_reg (&c, UNW_REG_IP, &ip)) < 0
92 || (ret = unw_get_reg (&c, UNW_REG_SP, &sp)) < 0)
93 panic ("unw_get_reg/unw_get_proc_name() failed: ret=%d\n", ret);
94
95 if (n == 0)
96 start_ip = ip;
97
98 buf[0] = '\0';
99 if (print_names)
100 unw_get_proc_name (&c, buf, sizeof (buf), &off);
101
102 if (verbose)
103 {
104 if (off)
105 {
106 len = strlen (buf);
107 if (len >= sizeof (buf) - 32)
108 len = sizeof (buf) - 32;
109 sprintf (buf + len, "+0x%lx", (unsigned long) off);
110 }
111 printf ("%016lx %-32s (sp=%016lx)\n", (long) ip, buf, (long) sp);
112 }
113
114 if ((ret = unw_get_proc_info (&c, &pi)) < 0)
115 panic ("unw_get_proc_info(ip=0x%lx) failed: ret=%d\n", (long) ip, ret);
116 else if (verbose)
117 printf ("\tproc=%016lx-%016lx\n\thandler=%lx lsda=%lx",
118 (long) pi.start_ip, (long) pi.end_ip,
119 (long) pi.handler, (long) pi.lsda);
120
121 #if UNW_TARGET_IA64
122 {
123 unw_word_t bsp;
124
125 if ((ret = unw_get_reg (&c, UNW_IA64_BSP, &bsp)) < 0)
126 panic ("unw_get_reg() failed: ret=%d\n", ret);
127 else if (verbose)
128 printf (" bsp=%lx", bsp);
129 }
130 #endif
131 if (verbose)
132 printf ("\n");
133
134 ret = unw_step (&c);
135 if (ret < 0)
136 {
137 unw_get_reg (&c, UNW_REG_IP, &ip);
138 panic ("FAILURE: unw_step() returned %d for ip=%lx (start ip=%lx)\n",
139 ret, (long) ip, (long) start_ip);
140 }
141
142 if (++n > 64)
143 {
144 /* guard against bad unwind info in old libraries... */
145 panic ("too deeply nested---assuming bogus unwind (start ip=%lx)\n",
146 (long) start_ip);
147 break;
148 }
149 if (nerrors > nerrors_max)
150 {
151 panic ("Too many errors (%d)!\n", nerrors);
152 break;
153 }
154 }
155 while (ret > 0);
156
157 if (ret < 0)
158 panic ("unwind failed with ret=%d\n", ret);
159
160 if (verbose)
161 printf ("================\n\n");
162 }
163
164 static pid_t target_pid;
target_pid_kill(void)165 static void target_pid_kill (void)
166 {
167 kill (target_pid, SIGKILL);
168 }
169
170 int
main(int argc,char ** argv)171 main (int argc, char **argv)
172 {
173 int status, pid, pending_sig, optind = 1, state = 1;
174
175 as = unw_create_addr_space (&_UPT_accessors, 0);
176 if (!as)
177 panic ("unw_create_addr_space() failed");
178
179 if (argc == 1)
180 {
181 static char *args[] = { "self", "/bin/ls", "/usr", NULL };
182
183 /* automated test case */
184 argv = args;
185 }
186 else if (argc > 1)
187 while (argv[optind][0] == '-')
188 {
189 if (strcmp (argv[optind], "-v") == 0)
190 ++optind, verbose = 1;
191 else if (strcmp (argv[optind], "-i") == 0)
192 ++optind, trace_mode = INSTRUCTION; /* backtrace at each insn */
193 else if (strcmp (argv[optind], "-s") == 0)
194 ++optind, trace_mode = SYSCALL; /* backtrace at each syscall */
195 else if (strcmp (argv[optind], "-t") == 0)
196 /* Execute until raise(SIGUSR1), then backtrace at each insn
197 until raise(SIGUSR2). */
198 ++optind, trace_mode = TRIGGER;
199 else if (strcmp (argv[optind], "-c") == 0)
200 /* Enable caching of unwind-info. */
201 ++optind, unw_set_caching_policy (as, UNW_CACHE_GLOBAL);
202 else if (strcmp (argv[optind], "-n") == 0)
203 /* Don't look-up and print symbol names. */
204 ++optind, print_names = 0;
205 else
206 fprintf(stderr, "unrecognized option: %s\n", argv[optind++]);
207 if (optind >= argc)
208 break;
209 }
210
211 target_pid = fork ();
212 if (!target_pid)
213 {
214 /* child */
215
216 if (!verbose)
217 dup2 (open ("/dev/null", O_WRONLY), 1);
218
219 #if HAVE_DECL_PTRACE_TRACEME
220 ptrace (PTRACE_TRACEME, 0, 0, 0);
221 #elif HAVE_DECL_PT_TRACE_ME
222 ptrace (PT_TRACE_ME, 0, 0, 0);
223 #else
224 #error Trace me
225 #endif
226
227 if ((argc > 1) && (optind == argc)) {
228 fprintf(stderr, "Need to specify a command line for the child\n");
229 exit (-1);
230 }
231 execve (argv[optind], argv + optind, environ);
232 _exit (-1);
233 }
234 atexit (target_pid_kill);
235
236 ui = _UPT_create (target_pid);
237
238 while (nerrors <= nerrors_max)
239 {
240 pid = wait4 (-1, &status, 0, NULL);
241 if (pid == -1)
242 {
243 if (errno == EINTR)
244 continue;
245
246 panic ("wait4() failed (errno=%d)\n", errno);
247 }
248 pending_sig = 0;
249 if (WIFSIGNALED (status) || WIFEXITED (status)
250 || (WIFSTOPPED (status) && WSTOPSIG (status) != SIGTRAP))
251 {
252 if (WIFEXITED (status))
253 {
254 if (WEXITSTATUS (status) != 0)
255 panic ("child's exit status %d\n", WEXITSTATUS (status));
256 break;
257 }
258 else if (WIFSIGNALED (status))
259 {
260 if (!killed)
261 panic ("child terminated by signal %d\n", WTERMSIG (status));
262 break;
263 }
264 else
265 {
266 pending_sig = WSTOPSIG (status);
267 /* Avoid deadlock: */
268 if (WSTOPSIG (status) == SIGKILL)
269 break;
270 if (trace_mode == TRIGGER)
271 {
272 if (WSTOPSIG (status) == SIGUSR1)
273 state = 0;
274 else if (WSTOPSIG (status) == SIGUSR2)
275 state = 1;
276 }
277 if (WSTOPSIG (status) != SIGUSR1 && WSTOPSIG (status) != SIGUSR2)
278 {
279 static int count = 0;
280
281 if (count++ > 100)
282 {
283 panic ("Too many child unexpected signals (now %d)\n",
284 WSTOPSIG (status));
285 killed = 1;
286 }
287 }
288 }
289 }
290
291 switch (trace_mode)
292 {
293 case TRIGGER:
294 if (state)
295 #if HAVE_DECL_PTRACE_CONT
296 ptrace (PTRACE_CONT, target_pid, 0, 0);
297 #elif HAVE_DECL_PT_CONTINUE
298 ptrace (PT_CONTINUE, target_pid, (caddr_t)1, 0);
299 #else
300 #error Port me
301 #endif
302 else
303 {
304 do_backtrace ();
305 #if HAVE_DECL_PTRACE_SINGLESTEP
306 ptrace (PTRACE_SINGLESTEP, target_pid, 0, pending_sig);
307 #elif HAVE_DECL_PT_STEP
308 ptrace (PT_STEP, target_pid, (caddr_t)1, pending_sig);
309 #else
310 #error Singlestep me
311 #endif
312 }
313 break;
314
315 case SYSCALL:
316 if (!state)
317 do_backtrace ();
318 state ^= 1;
319 #if HAVE_DECL_PTRACE_SYSCALL
320 ptrace (PTRACE_SYSCALL, target_pid, 0, pending_sig);
321 #elif HAVE_DECL_PT_SYSCALL
322 ptrace (PT_SYSCALL, target_pid, (caddr_t)1, pending_sig);
323 #else
324 #error Syscall me
325 #endif
326 break;
327
328 case INSTRUCTION:
329 do_backtrace ();
330 #if HAVE_DECL_PTRACE_SINGLESTEP
331 ptrace (PTRACE_SINGLESTEP, target_pid, 0, pending_sig);
332 #elif HAVE_DECL_PT_STEP
333 ptrace (PT_STEP, target_pid, (caddr_t)1, pending_sig);
334 #else
335 #error Singlestep me
336 #endif
337 break;
338 }
339 if (killed)
340 kill (target_pid, SIGKILL);
341 }
342
343 _UPT_destroy (ui);
344 unw_destroy_addr_space (as);
345
346 if (nerrors)
347 {
348 printf ("FAILURE: detected %d errors\n", nerrors);
349 exit (-1);
350 }
351 if (verbose)
352 printf ("SUCCESS\n");
353
354 return 0;
355 }
356
357 #endif /* !HAVE_TTRACE */
358