1 /*
2 * Copyright (C) 2016 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 "plugin.h"
18
19 #include <dlfcn.h>
20
21 #include "android-base/stringprintf.h"
22
23 namespace art {
24
25 using android::base::StringPrintf;
26
27 const char* PLUGIN_INITIALIZATION_FUNCTION_NAME = "ArtPlugin_Initialize";
28 const char* PLUGIN_DEINITIALIZATION_FUNCTION_NAME = "ArtPlugin_Deinitialize";
29
Plugin(const Plugin & other)30 Plugin::Plugin(const Plugin& other) : library_(other.library_), dlopen_handle_(nullptr) {
31 CHECK(!other.IsLoaded()) << "Should not copy loaded plugins.";
32 }
33
Load(std::string * error_msg)34 bool Plugin::Load(/*out*/std::string* error_msg) {
35 DCHECK(!IsLoaded());
36 void* res = dlopen(library_.c_str(), RTLD_LAZY);
37 if (res == nullptr) {
38 *error_msg = StringPrintf("dlopen failed: %s", dlerror());
39 return false;
40 }
41 // Get the initializer function
42 PluginInitializationFunction init = reinterpret_cast<PluginInitializationFunction>(
43 dlsym(res, PLUGIN_INITIALIZATION_FUNCTION_NAME));
44 if (init != nullptr) {
45 if (!init()) {
46 dlclose(res);
47 *error_msg = StringPrintf("Initialization of plugin failed");
48 return false;
49 }
50 } else {
51 LOG(WARNING) << this << " does not include an initialization function";
52 }
53 dlopen_handle_ = res;
54 return true;
55 }
56
Unload()57 bool Plugin::Unload() {
58 DCHECK(IsLoaded());
59 bool ret = true;
60 void* handle = dlopen_handle_;
61 PluginDeinitializationFunction deinit = reinterpret_cast<PluginDeinitializationFunction>(
62 dlsym(handle, PLUGIN_DEINITIALIZATION_FUNCTION_NAME));
63 if (deinit != nullptr) {
64 if (!deinit()) {
65 LOG(WARNING) << this << " failed deinitialization";
66 ret = false;
67 }
68 } else {
69 LOG(WARNING) << this << " does not include a deinitialization function";
70 }
71 dlopen_handle_ = nullptr;
72 // Don't bother to actually dlclose since we are shutting down anyway and there might be small
73 // amounts of processing still being done.
74 return ret;
75 }
76
operator <<(std::ostream & os,const Plugin * m)77 std::ostream& operator<<(std::ostream &os, const Plugin* m) {
78 return os << *m;
79 }
80
operator <<(std::ostream & os,Plugin const & m)81 std::ostream& operator<<(std::ostream &os, Plugin const& m) {
82 return os << "Plugin { library=\"" << m.library_ << "\", handle=" << m.dlopen_handle_ << " }";
83 }
84
85 } // namespace art
86