1 /*
2 * Copyright (C) 2014 The Android Open Source Project
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in
12 * the documentation and/or other materials provided with the
13 * distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 // Contains wrapper to missing dladdr in API < 8
30
31 #if !__LP64__
32
33 #include <dlfcn.h>
34 #include <android/api-level.h>
35
36 #if __ANDROID_API__ < 8
37 typedef int Dl_info;
38 #endif // __ANDROID_API__ >= 8
39
40 typedef int (*dladdr_func_t)(const void *addr, Dl_info *info);
41
42 #if defined(__cplusplus)
43 extern "C"
44 #endif
my_dladdr(const void * addr,Dl_info * info)45 int my_dladdr(const void *addr, Dl_info *info)
46 {
47 static int initialized = 0;
48 static dladdr_func_t p_dladdr = 0;
49 if (!p_dladdr && !initialized) {
50 void *libdl = dlopen("libdl.so", RTLD_NOW);
51 // Other thread may enter here simultaneously but p_dladdr should be
52 // set to the same addres for "dladdr"
53 if (libdl) {
54 #if __ANDROID_API__ < 8
55 p_dladdr = 0;
56 #else
57 p_dladdr = (dladdr_func_t)dlsym(libdl, "dladdr");
58 #endif
59 }
60 initialized = 1;
61 }
62 return p_dladdr? p_dladdr(addr, info) : 0;
63 }
64
65
66 #ifdef TEST
67 #include <stdio.h>
main()68 int main()
69 {
70 void *libdl = dlopen("libc.so", RTLD_NOW);
71 void *h = dlsym(libdl, "printf");
72 Dl_info info;
73 int r = my_dladdr((char*)h+1, &info);
74 if (r)
75 printf("%p: %s, %x, %s, %p\n", h, info.dli_fname, info.dli_fbase, info.dli_sname, info.dli_saddr);
76 }
77
78 #endif // TEST
79 #endif // __LP64__
80