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