1 /*
2  * Copyright (C) 2015 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 #include <sys/cdefs.h>
17 
18 #include <private/bionic_defs.h>
19 
20 #include "pthread_internal.h"
21 
22 class thread_local_dtor {
23  public:
24   void (*func) (void *);
25   void *arg;
26   void *dso_handle; // unused...
27   thread_local_dtor* next;
28 };
29 
30 extern "C" int __cxa_thread_atexit_impl(void (*func) (void *), void *arg, void *dso_handle);
31 extern "C" void __loader_add_thread_local_dtor(void* dso_handle) __attribute__((weak));
32 extern "C" void __loader_remove_thread_local_dtor(void* dso_handle) __attribute__((weak));
33 
34 __BIONIC_WEAK_FOR_NATIVE_BRIDGE
__cxa_thread_atexit_impl(void (* func)(void *),void * arg,void * dso_handle)35 int __cxa_thread_atexit_impl(void (*func) (void *), void *arg, void *dso_handle) {
36   thread_local_dtor* dtor = new thread_local_dtor();
37 
38   dtor->func = func;
39   dtor->arg = arg;
40   dtor->dso_handle = dso_handle;
41 
42   pthread_internal_t* thread = __get_thread();
43   dtor->next = thread->thread_local_dtors;
44   thread->thread_local_dtors = dtor;
45   if (__loader_add_thread_local_dtor != nullptr) {
46     __loader_add_thread_local_dtor(dso_handle);
47   }
48   return 0;
49 }
50 
__cxa_thread_finalize()51 extern "C" __LIBC_HIDDEN__ void __cxa_thread_finalize() {
52   pthread_internal_t* thread = __get_thread();
53   while (thread->thread_local_dtors != nullptr) {
54     thread_local_dtor* current = thread->thread_local_dtors;
55     thread->thread_local_dtors = current->next;
56 
57     current->func(current->arg);
58     if (__loader_remove_thread_local_dtor != nullptr) {
59       __loader_remove_thread_local_dtor(current->dso_handle);
60     }
61     delete current;
62   }
63 }
64