blob: b9f941dab3235507d74fd9a7c1daaf7d1ddaf417 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
//===-- Support/MutexGuard.h - Acquire/Release Mutex In Scope ---*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a guard for a block of code that ensures a Mutex is locked
// upon construction and released upon destruction.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_MUTEXGUARD_H
#define LLVM_SUPPORT_MUTEXGUARD_H
#include "llvm/Support/Mutex.h"
namespace llvm {
/// Instances of this class acquire a given Mutex Lock when constructed and
/// hold that lock until destruction. The intention is to instantiate one of
/// these on the stack at the top of some scope to be assured that C++
/// destruction of the object will always release the Mutex and thus avoid
/// a host of nasty multi-threading problems in the face of exceptions, etc.
/// @brief Guard a section of code with a Mutex.
class MutexGuard {
sys::Mutex &M;
MutexGuard(const MutexGuard &) LLVM_DELETED_FUNCTION;
void operator=(const MutexGuard &) LLVM_DELETED_FUNCTION;
public:
MutexGuard(sys::Mutex &m) : M(m) { M.lock(); }
~MutexGuard() { M.unlock(); }
/// holds - Returns true if this locker instance holds the specified lock.
/// This is mostly used in assertions to validate that the correct mutex
/// is held.
bool holds(const sys::Mutex& lock) const { return &M == &lock; }
};
}
#endif // LLVM_SUPPORT_MUTEXGUARD_H
|
