1/*
2 * Copyright (C) 2007 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <dlfcn.h>
18#include <link.h>
19#include <stdlib.h>
20#include <android/dlext.h>
21
22// These functions are exported by the loader
23// TODO(dimitry): replace these with reference to libc.so
24
25extern "C" {
26
27__attribute__((__weak__, visibility("default")))
28void* __loader_dlopen(const char* filename, int flags, const void* caller_addr);
29
30__attribute__((__weak__, visibility("default")))
31char* __loader_dlerror();
32
33__attribute__((__weak__, visibility("default")))
34void* __loader_dlsym(void* handle, const char* symbol, const void* caller_addr);
35
36__attribute__((__weak__, visibility("default")))
37void* __loader_dlvsym(void* handle,
38                      const char* symbol,
39                      const char* version,
40                      const void* caller_addr);
41
42__attribute__((__weak__, visibility("default")))
43int __loader_dladdr(const void* addr, Dl_info* info);
44
45__attribute__((__weak__, visibility("default")))
46int __loader_dlclose(void* handle);
47
48#if defined(__arm__)
49__attribute__((__weak__, visibility("default")))
50_Unwind_Ptr __loader_dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount);
51#endif
52
53__attribute__((__weak__, visibility("default")))
54int __loader_dl_iterate_phdr(int (*cb)(struct dl_phdr_info* info, size_t size, void* data),
55                             void* data);
56
57__attribute__((__weak__, visibility("default")))
58void __loader_android_get_LD_LIBRARY_PATH(char* buffer, size_t buffer_size);
59
60__attribute__((__weak__, visibility("default")))
61void __loader_android_update_LD_LIBRARY_PATH(const char* ld_library_path);
62
63__attribute__((__weak__, visibility("default")))
64void* __loader_android_dlopen_ext(const char* filename,
65                                  int flag,
66                                  const android_dlextinfo* extinfo,
67                                  const void* caller_addr);
68
69__attribute__((__weak__, visibility("default")))
70void __loader_android_set_application_target_sdk_version(uint32_t target);
71
72__attribute__((__weak__, visibility("default")))
73uint32_t __loader_android_get_application_target_sdk_version();
74
75__attribute__((__weak__, visibility("default")))
76bool __loader_android_init_anonymous_namespace(const char* shared_libs_sonames,
77                                               const char* library_search_path);
78
79__attribute__((__weak__, visibility("default")))
80struct android_namespace_t* __loader_android_create_namespace(
81                                const char* name,
82                                const char* ld_library_path,
83                                const char* default_library_path,
84                                uint64_t type,
85                                const char* permitted_when_isolated_path,
86                                struct android_namespace_t* parent,
87                                const void* caller_addr);
88
89__attribute__((__weak__, visibility("default")))
90bool __loader_android_link_namespaces(
91                                struct android_namespace_t* namespace_from,
92                                struct android_namespace_t* namespace_to,
93                                const char* shared_libs_sonames);
94
95__attribute__((__weak__, visibility("default")))
96void __loader_android_dlwarning(void* obj, void (*f)(void*, const char*));
97
98__attribute__((__weak__, visibility("default")))
99struct android_namespace_t* __loader_android_get_exported_namespace(const char* name);
100
101// Proxy calls to bionic loader
102__attribute__((__weak__))
103void* dlopen(const char* filename, int flag) {
104  const void* caller_addr = __builtin_return_address(0);
105  return __loader_dlopen(filename, flag, caller_addr);
106}
107
108__attribute__((__weak__))
109char* dlerror() {
110  return __loader_dlerror();
111}
112
113__attribute__((__weak__))
114void* dlsym(void* handle, const char* symbol) {
115  const void* caller_addr = __builtin_return_address(0);
116  return __loader_dlsym(handle, symbol, caller_addr);
117}
118
119__attribute__((__weak__))
120void* dlvsym(void* handle, const char* symbol, const char* version) {
121  const void* caller_addr = __builtin_return_address(0);
122  return __loader_dlvsym(handle, symbol, version, caller_addr);
123}
124
125__attribute__((__weak__))
126int dladdr(const void* addr, Dl_info* info) {
127  return __loader_dladdr(addr, info);
128}
129
130__attribute__((__weak__))
131int dlclose(void* handle) {
132  return __loader_dlclose(handle);
133}
134
135#if defined(__arm__)
136__attribute__((__weak__))
137_Unwind_Ptr dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount) {
138  return __loader_dl_unwind_find_exidx(pc, pcount);
139}
140#endif
141
142/*
143 * This needs to be defined as weak because it is also defined in libc.a.
144 * Without this, static executables will have a multiple definition error.
145 */
146__attribute__((__weak__))
147int dl_iterate_phdr(int (*cb)(struct dl_phdr_info* info, size_t size, void* data), void* data) {
148  return __loader_dl_iterate_phdr(cb, data);
149}
150
151__attribute__((__weak__))
152void android_get_LD_LIBRARY_PATH(char* buffer, size_t buffer_size) {
153  __loader_android_get_LD_LIBRARY_PATH(buffer, buffer_size);
154}
155
156__attribute__((__weak__))
157void android_update_LD_LIBRARY_PATH(const char* ld_library_path) {
158  __loader_android_update_LD_LIBRARY_PATH(ld_library_path);
159}
160
161__attribute__((__weak__))
162void* android_dlopen_ext(const char* filename, int flag, const android_dlextinfo* extinfo) {
163  const void* caller_addr = __builtin_return_address(0);
164  return __loader_android_dlopen_ext(filename, flag, extinfo, caller_addr);
165}
166
167__attribute__((__weak__))
168void android_set_application_target_sdk_version(uint32_t target) {
169  __loader_android_set_application_target_sdk_version(target);
170}
171
172__attribute__((__weak__))
173uint32_t android_get_application_target_sdk_version() {
174  return __loader_android_get_application_target_sdk_version();
175}
176
177__attribute__((__weak__))
178bool android_init_anonymous_namespace(const char* shared_libs_sonames,
179                                      const char* library_search_path) {
180  return __loader_android_init_anonymous_namespace(shared_libs_sonames, library_search_path);
181}
182
183__attribute__((__weak__))
184struct android_namespace_t* android_create_namespace(const char* name,
185                                                     const char* ld_library_path,
186                                                     const char* default_library_path,
187                                                     uint64_t type,
188                                                     const char* permitted_when_isolated_path,
189                                                     struct android_namespace_t* parent) {
190  const void* caller_addr = __builtin_return_address(0);
191  return __loader_android_create_namespace(name,
192                                           ld_library_path,
193                                           default_library_path,
194                                           type,
195                                           permitted_when_isolated_path,
196                                           parent,
197                                           caller_addr);
198}
199
200__attribute__((__weak__))
201bool android_link_namespaces(struct android_namespace_t* namespace_from,
202                             struct android_namespace_t* namespace_to,
203                             const char* shared_libs_sonames) {
204  return __loader_android_link_namespaces(namespace_from, namespace_to, shared_libs_sonames);
205}
206
207__attribute__((__weak__))
208void android_dlwarning(void* obj, void (*f)(void*, const char*)) {
209  __loader_android_dlwarning(obj, f);
210}
211
212__attribute__((__weak__))
213struct android_namespace_t* android_get_exported_namespace(const char* name) {
214  return __loader_android_get_exported_namespace(name);
215}
216
217#if defined(__arm__)
218// An arm32 unwinding table has an R_ARM_NONE relocation to
219// __aeabi_unwind_cpp_pr0. This shared library will never invoke the unwinder,
220// so it doesn't actually need the routine. Define a dummy version here,
221// because the real version calls libc functions (e.g. memcpy, abort), which
222// would create a dependency cycle with libc.so.
223__attribute__((visibility("hidden")))
224void __aeabi_unwind_cpp_pr0() {
225  __builtin_trap();
226}
227#endif
228
229} // extern "C"
230