xref: /freebsd/contrib/llvm-project/compiler-rt/lib/sanitizer_common/sanitizer_stoptheworld.h (revision 25ecdc7d52770caf1c9b44b5ec11f468f6b636f3)
1 //===-- sanitizer_stoptheworld.h --------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Defines the StopTheWorld function which suspends the execution of the current
10 // process and runs the user-supplied callback in the same address space.
11 //
12 //===----------------------------------------------------------------------===//
13 #ifndef SANITIZER_STOPTHEWORLD_H
14 #define SANITIZER_STOPTHEWORLD_H
15 
16 #include "sanitizer_internal_defs.h"
17 #include "sanitizer_common.h"
18 
19 namespace __sanitizer {
20 
21 enum PtraceRegistersStatus {
22   REGISTERS_UNAVAILABLE_FATAL = -1,
23   REGISTERS_UNAVAILABLE = 0,
24   REGISTERS_AVAILABLE = 1
25 };
26 
27 // Holds the list of suspended threads and provides an interface to dump their
28 // register contexts.
29 class SuspendedThreadsList {
30  public:
31   SuspendedThreadsList() = default;
32 
33   // Can't declare pure virtual functions in sanitizer runtimes:
34   // __cxa_pure_virtual might be unavailable. Use UNIMPLEMENTED() instead.
35   virtual PtraceRegistersStatus GetRegistersAndSP(uptr index, uptr *buffer,
36                                                   uptr *sp) const {
37     UNIMPLEMENTED();
38   }
39 
40   // The buffer in GetRegistersAndSP should be at least this big.
41   virtual uptr RegisterCount() const { UNIMPLEMENTED(); }
42   virtual uptr ThreadCount() const { UNIMPLEMENTED(); }
43   virtual tid_t GetThreadID(uptr index) const { UNIMPLEMENTED(); }
44 
45  private:
46   // Prohibit copy and assign.
47   SuspendedThreadsList(const SuspendedThreadsList&);
48   void operator=(const SuspendedThreadsList&);
49 };
50 
51 typedef void (*StopTheWorldCallback)(
52     const SuspendedThreadsList &suspended_threads_list,
53     void *argument);
54 
55 // Suspend all threads in the current process and run the callback on the list
56 // of suspended threads. This function will resume the threads before returning.
57 // The callback should not call any libc functions. The callback must not call
58 // exit() nor _exit() and instead return to the caller.
59 // This function should NOT be called from multiple threads simultaneously.
60 void StopTheWorld(StopTheWorldCallback callback, void *argument);
61 
62 }  // namespace __sanitizer
63 
64 #endif  // SANITIZER_STOPTHEWORLD_H
65