1 /* libunwind - a platform-independent unwind library
2 Copyright (C) 2009 Google, Inc
3 Contributed by Arun Sharma <arun.sharma@google.com>
4
5 Permission is hereby granted, free of charge, to any person obtaining
6 a copy of this software and associated documentation files (the
7 "Software"), to deal in the Software without restriction, including
8 without limitation the rights to use, copy, modify, merge, publish,
9 distribute, sublicense, and/or sell copies of the Software, and to
10 permit persons to whom the Software is furnished to do so, subject to
11 the following conditions:
12
13 The above copyright notice and this permission notice shall be
14 included in all copies or substantial portions of the Software.
15
16 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
23
24 #include <unistd.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <dlfcn.h>
28 #include <libunwind.h>
29
30 #define panic(args...) \
31 { fprintf (stderr, args); exit (-1); }
32
33 int verbose;
34 int num_errors;
35 int in_unwind;
36
37 void *
malloc(size_t s)38 malloc(size_t s)
39 {
40 static void * (*func)();
41
42 if(!func)
43 func = (void *(*)()) dlsym(RTLD_NEXT, "malloc");
44
45 if (in_unwind) {
46 num_errors++;
47 return NULL;
48 } else {
49 return func(s);
50 }
51 }
52
53 static void
do_backtrace(void)54 do_backtrace (void)
55 {
56 unw_word_t ip, sp;
57 unw_cursor_t cursor;
58 unw_context_t uc;
59 int ret;
60
61 in_unwind = 1;
62 unw_getcontext (&uc);
63 if (unw_init_local (&cursor, &uc) < 0)
64 panic ("unw_init_local failed!\n");
65
66 do
67 {
68 unw_get_reg (&cursor, UNW_REG_IP, &ip);
69 unw_get_reg (&cursor, UNW_REG_SP, &sp);
70
71 ret = unw_step (&cursor);
72 if (ret < 0)
73 {
74 ++num_errors;
75 }
76 }
77 while (ret > 0);
78 in_unwind = 0;
79 }
80
81 void
foo3(void)82 foo3 (void)
83 {
84 do_backtrace ();
85 }
86
87 void
foo2(void)88 foo2 (void)
89 {
90 foo3 ();
91 }
92
93 void
foo1(void)94 foo1 (void)
95 {
96 foo2 ();
97 }
98
99 int
main(void)100 main (void)
101 {
102 foo1();
103
104 if (num_errors > 0)
105 {
106 fprintf (stderr, "FAILURE: detected %d errors\n", num_errors);
107 exit (-1);
108 }
109 return 0;
110 }
111