platform_bionic/libdl/libdl.c
Jiyong Park d7c4832e6a linker: add android_get_exported_namespace
Depending on how ld.config.txt is configured, there can be multiple
built-in namespaces created by the linker from the beginning of a
process. android_get_exported_namespace is a platform only API for
getting a handle (android_namespace_t*) to one of the built-in namespaces
with given name. The returned namespace can then be given to
android_dlopen_ext in order to explicitly specify the target namespace
where the library is searched and loaded from.

Note that this function only returns 'exported' namespaces created via
ld.config.txt file. In order to export a namespace, the visible property
should be set to true:

namespace.<name>.visible = true

Namespaces are hidden by default. Hidden namespaces and namespaces
that are created programmatically, notably 'classloader-namespace',
aren't returned by this function.

Bug: 36851137
Test: confirmed that namespaces created with ld.config.txt is retrieved.
Test: linker-unit-tests passes
Change-Id: I0d05fa7e0e116009edf8ea362ab46774bc617cbf
2017-04-06 15:20:04 -07:00

191 lines
7.4 KiB
C

/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <dlfcn.h>
#include <link.h>
#include <stdlib.h>
#include <stdbool.h>
#include <android/dlext.h>
// These functions are exported by the loader
// TODO(dimitry): replace these with reference to libc.so
__attribute__((__weak__, visibility("default")))
void* __loader_dlopen(const char* filename, int flags, const void* caller_addr);
__attribute__((__weak__, visibility("default")))
void* __loader_dlerror();
__attribute__((__weak__, visibility("default")))
void* __loader_dlsym(void* handle, const char* symbol, const void* caller_addr);
__attribute__((__weak__, visibility("default")))
void* __loader_dlvsym(void* handle,
const char* symbol,
const char* version,
const void* caller_addr);
__attribute__((__weak__, visibility("default")))
int __loader_dladdr(const void* addr, Dl_info* info);
__attribute__((__weak__, visibility("default")))
int __loader_dlclose(void* handle);
#if defined(__arm__)
__attribute__((__weak__, visibility("default")))
_Unwind_Ptr __loader_dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount);
#endif
__attribute__((__weak__, visibility("default")))
int __loader_dl_iterate_phdr(int (*cb)(struct dl_phdr_info* info, size_t size, void* data),
void* data);
__attribute__((__weak__, visibility("default")))
void __loader_android_get_LD_LIBRARY_PATH(char* buffer, size_t buffer_size);
__attribute__((__weak__, visibility("default")))
void __loader_android_update_LD_LIBRARY_PATH(const char* ld_library_path);
__attribute__((__weak__, visibility("default")))
void* __loader_android_dlopen_ext(const char* filename,
int flag,
const android_dlextinfo* extinfo,
const void* caller_addr);
__attribute__((__weak__, visibility("default")))
void __loader_android_set_application_target_sdk_version(uint32_t target);
__attribute__((__weak__, visibility("default")))
uint32_t __loader_android_get_application_target_sdk_version();
__attribute__((__weak__, visibility("default")))
bool __loader_android_init_anonymous_namespace(const char* shared_libs_sonames,
const char* library_search_path);
__attribute__((__weak__, visibility("default")))
struct android_namespace_t* __loader_android_create_namespace(
const char* name,
const char* ld_library_path,
const char* default_library_path,
uint64_t type,
const char* permitted_when_isolated_path,
struct android_namespace_t* parent,
const void* caller_addr);
__attribute__((__weak__, visibility("default")))
bool __loader_android_link_namespaces(
struct android_namespace_t* namespace_from,
struct android_namespace_t* namespace_to,
const char* shared_libs_sonames);
__attribute__((__weak__, visibility("default")))
void __loader_android_dlwarning(void* obj, void (*f)(void*, const char*));
__attribute__((__weak__, visibility("default")))
struct android_namespace_t* __loader_android_get_exported_namespace(const char* name);
// Proxy calls to bionic loader
void* dlopen(const char* filename, int flag) {
const void* caller_addr = __builtin_return_address(0);
return __loader_dlopen(filename, flag, caller_addr);
}
char* dlerror() {
return __loader_dlerror();
}
void* dlsym(void* handle, const char* symbol) {
const void* caller_addr = __builtin_return_address(0);
return __loader_dlsym(handle, symbol, caller_addr);
}
void* dlvsym(void* handle, const char* symbol, const char* version) {
const void* caller_addr = __builtin_return_address(0);
return __loader_dlvsym(handle, symbol, version, caller_addr);
}
int dladdr(const void* addr, Dl_info* info) {
return __loader_dladdr(addr, info);
}
int dlclose(void* handle) {
return __loader_dlclose(handle);
}
#if defined(__arm__)
_Unwind_Ptr dl_unwind_find_exidx(_Unwind_Ptr pc, int* pcount) {
return __loader_dl_unwind_find_exidx(pc, pcount);
}
#endif
int dl_iterate_phdr(int (*cb)(struct dl_phdr_info* info, size_t size, void* data), void* data) {
return __loader_dl_iterate_phdr(cb, data);
}
void android_get_LD_LIBRARY_PATH(char* buffer, size_t buffer_size) {
__loader_android_get_LD_LIBRARY_PATH(buffer, buffer_size);
}
void android_update_LD_LIBRARY_PATH(const char* ld_library_path) {
__loader_android_update_LD_LIBRARY_PATH(ld_library_path);
}
void* android_dlopen_ext(const char* filename, int flag, const android_dlextinfo* extinfo) {
const void* caller_addr = __builtin_return_address(0);
return __loader_android_dlopen_ext(filename, flag, extinfo, caller_addr);
}
void android_set_application_target_sdk_version(uint32_t target) {
__loader_android_set_application_target_sdk_version(target);
}
uint32_t android_get_application_target_sdk_version() {
return __loader_android_get_application_target_sdk_version();
}
bool android_init_anonymous_namespace(const char* shared_libs_sonames,
const char* library_search_path) {
return __loader_android_init_anonymous_namespace(shared_libs_sonames, library_search_path);
}
struct android_namespace_t* android_create_namespace(const char* name,
const char* ld_library_path,
const char* default_library_path,
uint64_t type,
const char* permitted_when_isolated_path,
struct android_namespace_t* parent) {
const void* caller_addr = __builtin_return_address(0);
return __loader_android_create_namespace(name,
ld_library_path,
default_library_path,
type,
permitted_when_isolated_path,
parent,
caller_addr);
}
bool android_link_namespaces(struct android_namespace_t* namespace_from,
struct android_namespace_t* namespace_to,
const char* shared_libs_sonames) {
return __loader_android_link_namespaces(namespace_from, namespace_to, shared_libs_sonames);
}
void android_dlwarning(void* obj, void (*f)(void*, const char*)) {
__loader_android_dlwarning(obj, f);
}
struct android_namespace_t* android_get_exported_namespace(const char* name) {
return __loader_android_get_exported_namespace(name);
}