Bitcoin ABC  0.28.12
P2P Digital Currency
threadsafety.h
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1 // Copyright (c) 2009-2010 Satoshi Nakamoto
2 // Copyright (c) 2009-2014 The Bitcoin Core developers
3 // Distributed under the MIT software license, see the accompanying
4 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
5 
6 #ifndef BITCOIN_THREADSAFETY_H
7 #define BITCOIN_THREADSAFETY_H
8 
9 #include <mutex>
10 
11 #ifdef __clang__
12 // TL;DR Add GUARDED_BY(mutex) to member variables. The others are rarely
13 // necessary. Ex: int nFoo GUARDED_BY(cs_foo);
14 //
15 // See https://clang.llvm.org/docs/ThreadSafetyAnalysis.html for documentation.
16 // The clang compiler can do advanced static analysis of locking when given the
17 // -Wthread-safety option.
18 #define LOCKABLE __attribute__((lockable))
19 #define SCOPED_LOCKABLE __attribute__((scoped_lockable))
20 #define GUARDED_BY(x) __attribute__((guarded_by(x)))
21 #define PT_GUARDED_BY(x) __attribute__((pt_guarded_by(x)))
22 #define ACQUIRED_AFTER(...) __attribute__((acquired_after(__VA_ARGS__)))
23 #define ACQUIRED_BEFORE(...) __attribute__((acquired_before(__VA_ARGS__)))
24 #define EXCLUSIVE_LOCK_FUNCTION(...) \
25  __attribute__((exclusive_lock_function(__VA_ARGS__)))
26 #define SHARED_LOCK_FUNCTION(...) \
27  __attribute__((shared_lock_function(__VA_ARGS__)))
28 #define EXCLUSIVE_TRYLOCK_FUNCTION(...) \
29  __attribute__((exclusive_trylock_function(__VA_ARGS__)))
30 #define SHARED_TRYLOCK_FUNCTION(...) \
31  __attribute__((shared_trylock_function(__VA_ARGS__)))
32 #define UNLOCK_FUNCTION(...) __attribute__((unlock_function(__VA_ARGS__)))
33 #define LOCK_RETURNED(x) __attribute__((lock_returned(x)))
34 #define LOCKS_EXCLUDED(...) __attribute__((locks_excluded(__VA_ARGS__)))
35 #define EXCLUSIVE_LOCKS_REQUIRED(...) \
36  __attribute__((exclusive_locks_required(__VA_ARGS__)))
37 #define SHARED_LOCKS_REQUIRED(...) \
38  __attribute__((shared_locks_required(__VA_ARGS__)))
39 #define NO_THREAD_SAFETY_ANALYSIS __attribute__((no_thread_safety_analysis))
40 #define ASSERT_EXCLUSIVE_LOCK(...) \
41  __attribute__((assert_exclusive_lock(__VA_ARGS__)))
42 #else
43 #define LOCKABLE
44 #define SCOPED_LOCKABLE
45 #define GUARDED_BY(x)
46 #define PT_GUARDED_BY(x)
47 #define ACQUIRED_AFTER(...)
48 #define ACQUIRED_BEFORE(...)
49 #define EXCLUSIVE_LOCK_FUNCTION(...)
50 #define SHARED_LOCK_FUNCTION(...)
51 #define EXCLUSIVE_TRYLOCK_FUNCTION(...)
52 #define SHARED_TRYLOCK_FUNCTION(...)
53 #define UNLOCK_FUNCTION(...)
54 #define LOCK_RETURNED(x)
55 #define LOCKS_EXCLUDED(...)
56 #define EXCLUSIVE_LOCKS_REQUIRED(...)
57 #define SHARED_LOCKS_REQUIRED(...)
58 #define NO_THREAD_SAFETY_ANALYSIS
59 #define ASSERT_EXCLUSIVE_LOCK(...)
60 #endif // __GNUC__
61 
62 // StdMutex provides an annotated version of std::mutex for us,
63 // and should only be used when sync.h Mutex/LOCK/etc are not usable.
64 class LOCKABLE StdMutex : public std::mutex {
65 public:
66 #ifdef __clang__
71  const StdMutex &operator!() const { return *this; }
72 #endif // __clang__
73 };
74 
75 // StdLockGuard provides an annotated version of std::lock_guard for us,
76 // and should only be used when sync.h Mutex/LOCK/etc are not usable.
77 class SCOPED_LOCKABLE StdLockGuard : public std::lock_guard<StdMutex> {
78 public:
80  : std::lock_guard<StdMutex>(cs) {}
82 };
83 
84 #endif // BITCOIN_THREADSAFETY_H
~StdLockGuard() UNLOCK_FUNCTION()
Definition: threadsafety.h:81
StdLockGuard(StdMutex &cs) EXCLUSIVE_LOCK_FUNCTION(cs)
Definition: threadsafety.h:79
static void pool cs
Implement std::hash so RCUPtr can be used as a key for maps or sets.
Definition: rcu.h:257
#define EXCLUSIVE_LOCK_FUNCTION(...)
Definition: threadsafety.h:49
#define SCOPED_LOCKABLE
Definition: threadsafety.h:44
#define LOCKABLE
Definition: threadsafety.h:43
#define UNLOCK_FUNCTION(...)
Definition: threadsafety.h:53