1//===------------------------- thread.cpp----------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is dual licensed under the MIT and the University of Illinois Open
6// Source Licenses. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "thread"
11#include "exception"
12#include "vector"
13#include "future"
14#include "limits"
15#include <sys/types.h>
16#if !defined(_WIN32)
17#if !defined(__sun__) && !defined(__linux__) && !defined(_AIX)
18#include <sys/sysctl.h>
19#endif // !__sun__ && !__linux__ && !_AIX
20#include <unistd.h>
21#endif // !_WIN32
22
23#if defined(__NetBSD__)
24#pragma weak pthread_create // Do not create libpthread dependency
25#endif
26#if defined(_WIN32)
27#include <windows.h>
28#endif
29
30_LIBCPP_BEGIN_NAMESPACE_STD
31
32thread::~thread()
33{
34    if (__t_ != 0)
35        terminate();
36}
37
38void
39thread::join()
40{
41    int ec = pthread_join(__t_, 0);
42#ifndef _LIBCPP_NO_EXCEPTIONS
43    if (ec)
44        throw system_error(error_code(ec, system_category()), "thread::join failed");
45#else
46    (void)ec;
47#endif  // _LIBCPP_NO_EXCEPTIONS
48    __t_ = 0;
49}
50
51void
52thread::detach()
53{
54    int ec = EINVAL;
55    if (__t_ != 0)
56    {
57        ec = pthread_detach(__t_);
58        if (ec == 0)
59            __t_ = 0;
60    }
61#ifndef _LIBCPP_NO_EXCEPTIONS
62    if (ec)
63        throw system_error(error_code(ec, system_category()), "thread::detach failed");
64#endif  // _LIBCPP_NO_EXCEPTIONS
65}
66
67unsigned
68thread::hardware_concurrency() _NOEXCEPT
69{
70#if defined(CTL_HW) && defined(HW_NCPU)
71    unsigned n;
72    int mib[2] = {CTL_HW, HW_NCPU};
73    std::size_t s = sizeof(n);
74    sysctl(mib, 2, &n, &s, 0, 0);
75    return n;
76#elif defined(_SC_NPROCESSORS_ONLN)
77    long result = sysconf(_SC_NPROCESSORS_ONLN);
78    // sysconf returns -1 if the name is invalid, the option does not exist or
79    // does not have a definite limit.
80    // if sysconf returns some other negative number, we have no idea
81    // what is going on. Default to something safe.
82    if (result < 0)
83        return 0;
84    return static_cast<unsigned>(result);
85#elif defined(_WIN32)
86    SYSTEM_INFO info;
87    GetSystemInfo(&info);
88    return info.dwNumberOfProcessors;
89#else  // defined(CTL_HW) && defined(HW_NCPU)
90    // TODO: grovel through /proc or check cpuid on x86 and similar
91    // instructions on other architectures.
92#   if defined(_MSC_VER) && ! defined(__clang__)
93        _LIBCPP_WARNING("hardware_concurrency not yet implemented")
94#   else
95#       warning hardware_concurrency not yet implemented
96#   endif
97    return 0;  // Means not computable [thread.thread.static]
98#endif  // defined(CTL_HW) && defined(HW_NCPU)
99}
100
101namespace this_thread
102{
103
104void
105sleep_for(const chrono::nanoseconds& ns)
106{
107    using namespace chrono;
108    if (ns > nanoseconds::zero())
109    {
110        seconds s = duration_cast<seconds>(ns);
111        timespec ts;
112        typedef decltype(ts.tv_sec) ts_sec;
113        _LIBCPP_CONSTEXPR ts_sec ts_sec_max = numeric_limits<ts_sec>::max();
114        if (s.count() < ts_sec_max)
115        {
116            ts.tv_sec = static_cast<ts_sec>(s.count());
117            ts.tv_nsec = static_cast<decltype(ts.tv_nsec)>((ns-s).count());
118        }
119        else
120        {
121            ts.tv_sec = ts_sec_max;
122            ts.tv_nsec = giga::num - 1;
123        }
124        nanosleep(&ts, 0);
125    }
126}
127
128}  // this_thread
129
130__thread_specific_ptr<__thread_struct>&
131__thread_local_data()
132{
133    static __thread_specific_ptr<__thread_struct> __p;
134    return __p;
135}
136
137// __thread_struct_imp
138
139template <class T>
140class _LIBCPP_HIDDEN __hidden_allocator
141{
142public:
143    typedef T  value_type;
144
145    T* allocate(size_t __n)
146        {return static_cast<T*>(::operator new(__n * sizeof(T)));}
147    void deallocate(T* __p, size_t) {::operator delete(static_cast<void*>(__p));}
148
149    size_t max_size() const {return size_t(~0) / sizeof(T);}
150};
151
152class _LIBCPP_HIDDEN __thread_struct_imp
153{
154    typedef vector<__assoc_sub_state*,
155                          __hidden_allocator<__assoc_sub_state*> > _AsyncStates;
156    typedef vector<pair<condition_variable*, mutex*>,
157               __hidden_allocator<pair<condition_variable*, mutex*> > > _Notify;
158
159    _AsyncStates async_states_;
160    _Notify notify_;
161
162    __thread_struct_imp(const __thread_struct_imp&);
163    __thread_struct_imp& operator=(const __thread_struct_imp&);
164public:
165    __thread_struct_imp() {}
166    ~__thread_struct_imp();
167
168    void notify_all_at_thread_exit(condition_variable* cv, mutex* m);
169    void __make_ready_at_thread_exit(__assoc_sub_state* __s);
170};
171
172__thread_struct_imp::~__thread_struct_imp()
173{
174    for (_Notify::iterator i = notify_.begin(), e = notify_.end();
175            i != e; ++i)
176    {
177        i->second->unlock();
178        i->first->notify_all();
179    }
180    for (_AsyncStates::iterator i = async_states_.begin(), e = async_states_.end();
181            i != e; ++i)
182    {
183        (*i)->__make_ready();
184        (*i)->__release_shared();
185    }
186}
187
188void
189__thread_struct_imp::notify_all_at_thread_exit(condition_variable* cv, mutex* m)
190{
191    notify_.push_back(pair<condition_variable*, mutex*>(cv, m));
192}
193
194void
195__thread_struct_imp::__make_ready_at_thread_exit(__assoc_sub_state* __s)
196{
197    async_states_.push_back(__s);
198    __s->__add_shared();
199}
200
201// __thread_struct
202
203__thread_struct::__thread_struct()
204    : __p_(new __thread_struct_imp)
205{
206}
207
208__thread_struct::~__thread_struct()
209{
210    delete __p_;
211}
212
213void
214__thread_struct::notify_all_at_thread_exit(condition_variable* cv, mutex* m)
215{
216    __p_->notify_all_at_thread_exit(cv, m);
217}
218
219void
220__thread_struct::__make_ready_at_thread_exit(__assoc_sub_state* __s)
221{
222    __p_->__make_ready_at_thread_exit(__s);
223}
224
225_LIBCPP_END_NAMESPACE_STD
226