1 /* libunwind - a platform-independent unwind library
2 Copyright (C) 2011 Google, Inc
3 Contributed by Paul Pluzhnikov <ppluzhnikov@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 #define UNW_LOCAL_ONLY
25 #include <libunwind.h>
26
27 #include <unistd.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <dlfcn.h>
31 #include <pthread.h>
32
33 #define panic(args...) \
34 { fprintf (stderr, args); exit (-1); }
35
36 int num_mallocs;
37 int num_callocs;
38 int in_unwind;
39
40 void *
calloc(size_t n,size_t s)41 calloc(size_t n, size_t s)
42 {
43 static void * (*func)(size_t, size_t);
44
45 #ifdef __GLIBC__
46 /* In glibc, dlsym() calls calloc. Calling dlsym(RTLD_NEXT, "calloc") here
47 causes infinite recursion. Instead, we simply use it by its other
48 name. */
49 extern void *__libc_calloc(size_t, size_t);
50 if (!func)
51 func = &__libc_calloc;
52 #else
53 if(!func)
54 func = dlsym(RTLD_NEXT, "calloc");
55 #endif
56
57 if (in_unwind) {
58 num_callocs++;
59 return NULL;
60 } else {
61 return func(n, s);
62 }
63 }
64
65 void *
malloc(size_t s)66 malloc(size_t s)
67 {
68 static void * (*func)(size_t);
69
70 if(!func)
71 func = dlsym(RTLD_NEXT, "malloc");
72
73 if (in_unwind) {
74 num_mallocs++;
75 return NULL;
76 } else {
77 return func(s);
78 }
79 }
80
81 static void
do_backtrace(void)82 do_backtrace (void)
83 {
84 const int num_levels = 100;
85 void *pc[num_levels];
86
87 in_unwind = 1;
88 unw_backtrace(pc, num_levels);
89 in_unwind = 0;
90 }
91
92 void
foo3(void)93 foo3 (void)
94 {
95 do_backtrace ();
96 }
97
98 void
foo2(void)99 foo2 (void)
100 {
101 foo3 ();
102 }
103
104 void
foo1(void)105 foo1 (void)
106 {
107 foo2 ();
108 }
109
110 int
main(void)111 main (void)
112 {
113 int i, num_errors;
114
115 /* Create (and leak) 100 TSDs, then call backtrace()
116 and check that it doesn't call malloc()/calloc(). */
117 for (i = 0; i < 100; ++i) {
118 pthread_key_t key;
119 if (pthread_key_create (&key, NULL))
120 panic ("FAILURE: unable to create key %d\n", i);
121 }
122 /* Call backtrace right after thread creation,
123 * where we are sure that we're not inside malloc */
124 do_backtrace();
125 num_mallocs = num_callocs = 0;
126 foo1 ();
127 num_errors = num_mallocs + num_callocs;
128 if (num_errors > 0)
129 {
130 fprintf (stderr,
131 "FAILURE: detected %d error%s (malloc: %d, calloc: %d)\n",
132 num_errors, num_errors > 1 ? "s" : "",
133 num_mallocs, num_callocs);
134 exit (-1);
135 }
136 return 0;
137 }
138