1//===-- PThreadMutex.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// Created by Greg Clayton on 6/16/07.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLDB_TOOLS_DEBUGSERVER_SOURCE_PTHREADMUTEX_H
14#define LLDB_TOOLS_DEBUGSERVER_SOURCE_PTHREADMUTEX_H
15
16#include <cassert>
17#include <cstdint>
18#include <pthread.h>
19
20//#define DEBUG_PTHREAD_MUTEX_DEADLOCKS 1
21
22#if defined(DEBUG_PTHREAD_MUTEX_DEADLOCKS)
23#define PTHREAD_MUTEX_LOCKER(var, mutex) \
24 PThreadMutex::Locker var(mutex, __FUNCTION__, __FILE__, __LINE__)
25
26#else
27#define PTHREAD_MUTEX_LOCKER(var, mutex) PThreadMutex::Locker var(mutex)
28#endif
29
30class PThreadMutex {
31public:
32 class Locker {
33 public:
34#if defined(DEBUG_PTHREAD_MUTEX_DEADLOCKS)
35
36 Locker(PThreadMutex &m, const char *function, const char *file, int line);
37 Locker(PThreadMutex *m, const char *function, const char *file, int line);
38 Locker(pthread_mutex_t *mutex, const char *function, const char *file,
39 int line);
40 ~Locker();
41 void Lock();
42 void Unlock();
43
44#else
45 Locker(PThreadMutex &m) : m_pMutex(m.Mutex()) { Lock(); }
46
47 Locker(PThreadMutex *m) : m_pMutex(m ? m->Mutex() : NULL) { Lock(); }
48
49 Locker(pthread_mutex_t *mutex) : m_pMutex(mutex) { Lock(); }
50
51 void Lock() {
52 if (m_pMutex)
53 ::pthread_mutex_lock(mutex: m_pMutex);
54 }
55
56 void Unlock() {
57 if (m_pMutex)
58 ::pthread_mutex_unlock(mutex: m_pMutex);
59 }
60
61 ~Locker() { Unlock(); }
62
63#endif
64
65 // unlock any the current mutex and lock the new one if it is valid
66 void Reset(pthread_mutex_t *pMutex = NULL) {
67 Unlock();
68 m_pMutex = pMutex;
69 Lock();
70 }
71 pthread_mutex_t *m_pMutex;
72#if defined(DEBUG_PTHREAD_MUTEX_DEADLOCKS)
73 const char *m_function;
74 const char *m_file;
75 int m_line;
76 uint64_t m_lock_time;
77#endif
78 };
79
80 PThreadMutex() {
81 int err;
82 err = ::pthread_mutex_init(mutex: &m_mutex, NULL);
83 assert(err == 0);
84 }
85
86 PThreadMutex(int type) {
87 int err;
88 ::pthread_mutexattr_t attr;
89 err = ::pthread_mutexattr_init(attr: &attr);
90 assert(err == 0);
91 err = ::pthread_mutexattr_settype(attr: &attr, kind: type);
92 assert(err == 0);
93 err = ::pthread_mutex_init(mutex: &m_mutex, mutexattr: &attr);
94 assert(err == 0);
95 err = ::pthread_mutexattr_destroy(attr: &attr);
96 assert(err == 0);
97 }
98
99 ~PThreadMutex() {
100 int err;
101 err = ::pthread_mutex_destroy(mutex: &m_mutex);
102 if (err != 0) {
103 err = Unlock();
104 if (err == 0)
105 ::pthread_mutex_destroy(mutex: &m_mutex);
106 }
107 }
108
109 pthread_mutex_t *Mutex() { return &m_mutex; }
110
111 int Lock() { return ::pthread_mutex_lock(mutex: &m_mutex); }
112
113 int Unlock() { return ::pthread_mutex_unlock(mutex: &m_mutex); }
114
115protected:
116 pthread_mutex_t m_mutex;
117};
118
119#endif
120

source code of lldb/tools/debugserver/source/PThreadMutex.h