summaryrefslogtreecommitdiff
path: root/js/src/threading/posix/Thread.cpp
blob: a5c2d2eacb25907d410eabfa64340faeaf29e2d6 (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
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "mozilla/Assertions.h"

#include <new>
#include <pthread.h>
#include <stdlib.h>
#include <string.h>

#if defined(__APPLE__) && defined(__MACH__)
#include <dlfcn.h>
#endif

#if defined(__DragonFly__) || defined(__FreeBSD__) || defined(__OpenBSD__)
#include <pthread_np.h>
#endif

#if defined(__linux__)
#include <sys/prctl.h>
#endif

#include "threading/Thread.h"

class js::Thread::Id::PlatformData
{
  friend class js::Thread;
  friend js::Thread::Id js::ThisThread::GetId();

  pthread_t ptThread;

  // pthread_t does not have a default initializer, so we have to carry a bool
  // to tell whether it is safe to compare or not.
  bool hasThread;
};

/* static */ js::HashNumber
js::Thread::Hasher::hash(const Lookup& l)
{
  return mozilla::HashBytes(&l.platformData()->ptThread, sizeof(pthread_t));
}

inline js::Thread::Id::PlatformData*
js::Thread::Id::platformData()
{
  static_assert(sizeof platformData_ >= sizeof(PlatformData),
                "platformData_ is too small");
  return reinterpret_cast<PlatformData*>(platformData_);
}

inline const js::Thread::Id::PlatformData*
js::Thread::Id::platformData() const
{
  static_assert(sizeof platformData_ >= sizeof(PlatformData),
                "platformData_ is too small");
  return reinterpret_cast<const PlatformData*>(platformData_);
}

js::Thread::Id::Id()
{
  platformData()->hasThread = false;
}

bool
js::Thread::Id::operator==(const Id& aOther) const
{
  const PlatformData& self = *platformData();
  const PlatformData& other = *aOther.platformData();
  return (!self.hasThread && !other.hasThread) ||
         (self.hasThread == other.hasThread &&
          pthread_equal(self.ptThread, other.ptThread));
}

js::Thread::Thread(Thread&& aOther)
{
  id_ = aOther.id_;
  aOther.id_ = Id();
}

js::Thread&
js::Thread::operator=(Thread&& aOther)
{
  MOZ_RELEASE_ASSERT(!joinable());
  id_ = aOther.id_;
  aOther.id_ = Id();
  return *this;
}

bool
js::Thread::create(void* (*aMain)(void*), void* aArg)
{
  pthread_attr_t attrs;
  int r = pthread_attr_init(&attrs);
  MOZ_RELEASE_ASSERT(!r);
  if (options_.stackSize()) {
    r = pthread_attr_setstacksize(&attrs, options_.stackSize());
    MOZ_RELEASE_ASSERT(!r);
  }
  r = pthread_create(&id_.platformData()->ptThread, &attrs, aMain, aArg);
  if (r) {
    // |pthread_create| may leave id_ in an undefined state.
    id_ = Id();
    return false;
  }
  id_.platformData()->hasThread = true;
  return true;
}

void
js::Thread::join()
{
  MOZ_RELEASE_ASSERT(joinable());
  int r = pthread_join(id_.platformData()->ptThread, nullptr);
  MOZ_RELEASE_ASSERT(!r);
  id_ = Id();
}

void
js::Thread::detach()
{
  MOZ_RELEASE_ASSERT(joinable());
  int r = pthread_detach(id_.platformData()->ptThread);
  MOZ_RELEASE_ASSERT(!r);
  id_ = Id();
}

js::Thread::Id
js::ThisThread::GetId()
{
  js::Thread::Id id;
  id.platformData()->ptThread = pthread_self();
  id.platformData()->hasThread = true;
  return id;
}

void
js::ThisThread::SetName(const char* name)
{
  MOZ_RELEASE_ASSERT(name);

#if (defined(__APPLE__) && defined(__MACH__)) || defined(__linux__)
  // On linux and OS X the name may not be longer than 16 bytes, including
  // the null terminator. Truncate the name to 15 characters.
  char nameBuf[16];

  strncpy(nameBuf, name, sizeof nameBuf - 1);
  nameBuf[sizeof nameBuf - 1] = '\0';
  name = nameBuf;
#endif

  int rv;
#if defined(__DragonFly__) || defined(__FreeBSD__) || defined(__OpenBSD__)
  pthread_set_name_np(pthread_self(), name);
  rv = 0;
#elif defined(__NetBSD__)
  rv = pthread_setname_np(pthread_self(), "%s", (void*)name);
#else
  rv = pthread_setname_np(pthread_self(), name);
#endif
  MOZ_RELEASE_ASSERT(!rv);
}

void
js::ThisThread::GetName(char* nameBuffer, size_t len)
{
  MOZ_RELEASE_ASSERT(len >= 16);

  int rv = -1;
#ifdef HAVE_PTHREAD_GETNAME_NP
  rv = pthread_getname_np(pthread_self(), nameBuffer, len);
#elif defined(__linux__)
  rv = prctl(PR_GET_NAME, reinterpret_cast<unsigned long>(nameBuffer));
#endif

  if (rv)
    nameBuffer[0] = '\0';
}