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 #ifndef LIBMEMUNREACHABLE_PTRACER_THREAD_H_
18 #define LIBMEMUNREACHABLE_PTRACER_THREAD_H_
19 
20 #include <functional>
21 #include <mutex>
22 
23 #include "android-base/macros.h"
24 
25 #include "Allocator.h"
26 
27 namespace android {
28 
29 class Stack;
30 
31 // PtracerThread is similar to std::thread, except that it creates a "thread"
32 // that can ptrace the other threads.  The thread is actually a separate
33 // process, with its own thread group, but shares address space and fds with
34 // the parent.
35 class PtracerThread {
36  public:
37   explicit PtracerThread(const std::function<int()>& func);
38   ~PtracerThread();
39   bool Start();
40   int Join();
41 
42  private:
43   void SetTracer(pid_t);
44   void ClearTracer();
45   void Kill();
46   DISALLOW_COPY_AND_ASSIGN(PtracerThread);
47   std::unique_ptr<Stack> stack_;
48   std::function<int()> func_;
49   std::mutex m_;
50   pid_t child_pid_;
51 };
52 
53 }  // namespace android
54 
55 #endif  // LIBMEMUNREACHABLE_PTRACER_THREAD_H_
56