xref: /llvm-project-15.0.7/libcxx/include/__threading_support (revision 6cb0d41c)

// -*- C++ -*-
//===----------------------------------------------------------------------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef _LIBCPP_THREADING_SUPPORT
#define _LIBCPP_THREADING_SUPPORT

#include <__config>

#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
#pragma GCC system_header
#endif

#ifndef _LIBCPP_HAS_NO_THREADS

#ifndef __libcpp_has_include
  #ifndef __has_include
    #define __libcpp_has_include(x) 0
  #else
    #define __libcpp_has_include(x) __has_include(x)
  #endif
#endif

#if defined(_LIBCPP_HAS_THREAD_API_EXTERNAL) && \
    !__libcpp_has_include(<__external_threading>)
// If the <__external_threading> header is absent, build libc++ against a
// pthread-oriented thread api but leave out its implementation. This setup
// allows building+testing of an externally-threaded library variant (on any
// platform that supports pthreads). Here, an 'externally-threaded' library
// variant is one where the implementation of the libc++ thread api is provided
// as a separate library.
#define _LIBCPP_HAS_THREAD_API_EXTERNAL_PTHREAD
#endif

#if defined(_LIBCPP_HAS_THREAD_API_EXTERNAL) && \
    __libcpp_has_include(<__external_threading>)
#include <__external_threading>
#else

#if defined(_LIBCPP_HAS_THREAD_API_PTHREAD) || \
    defined(_LIBCPP_HAS_THREAD_API_EXTERNAL_PTHREAD)
#include <pthread.h>
#include <sched.h>
#endif

#if defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
#define _LIBCPP_THREAD_ABI_VISIBILITY _LIBCPP_FUNC_VIS
#else
#define _LIBCPP_THREAD_ABI_VISIBILITY inline _LIBCPP_INLINE_VISIBILITY
#endif

_LIBCPP_BEGIN_NAMESPACE_STD

#if defined(_LIBCPP_HAS_THREAD_API_PTHREAD) || \
    defined(_LIBCPP_HAS_THREAD_API_EXTERNAL_PTHREAD)
// Mutex
typedef pthread_mutex_t __libcpp_mutex_t;
#define _LIBCPP_MUTEX_INITIALIZER PTHREAD_MUTEX_INITIALIZER

// Condition Variable
typedef pthread_cond_t __libcpp_condvar_t;
#define _LIBCPP_CONDVAR_INITIALIZER PTHREAD_COND_INITIALIZER

// THread ID
typedef pthread_t __libcpp_thread_id;

// Thread
typedef pthread_t __libcpp_thread_t;

// Thrad Local Storage
typedef pthread_key_t __libcpp_tls_key;
#endif

// Mutex
_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_recursive_mutex_init(__libcpp_mutex_t *__m);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_mutex_lock(__libcpp_mutex_t *__m);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_mutex_trylock(__libcpp_mutex_t *__m);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_mutex_unlock(__libcpp_mutex_t *__m);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_mutex_destroy(__libcpp_mutex_t *__m);

// Condition variable
_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_condvar_signal(__libcpp_condvar_t* __cv);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_condvar_broadcast(__libcpp_condvar_t* __cv);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_condvar_wait(__libcpp_condvar_t* __cv, __libcpp_mutex_t* __m);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_condvar_timedwait(__libcpp_condvar_t *__cv, __libcpp_mutex_t *__m,
                               timespec *__ts);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_condvar_destroy(__libcpp_condvar_t* __cv);

// Thread ID
_LIBCPP_THREAD_ABI_VISIBILITY
bool __libcpp_thread_id_equal(__libcpp_thread_id t1, __libcpp_thread_id t2);

_LIBCPP_THREAD_ABI_VISIBILITY
bool __libcpp_thread_id_less(__libcpp_thread_id t1, __libcpp_thread_id t2);

// Thread
_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_thread_create(__libcpp_thread_t *__t, void *(*__func)(void *),
                           void *__arg);

_LIBCPP_THREAD_ABI_VISIBILITY
__libcpp_thread_id __libcpp_thread_get_current_id();

_LIBCPP_THREAD_ABI_VISIBILITY
__libcpp_thread_id __libcpp_thread_get_id(const __libcpp_thread_t *__t);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_thread_join(__libcpp_thread_t *__t);

_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_thread_detach(__libcpp_thread_t *__t);

_LIBCPP_THREAD_ABI_VISIBILITY
void __libcpp_thread_yield();

// Thread local storage
_LIBCPP_THREAD_ABI_VISIBILITY
int __libcpp_tls_create(__libcpp_tls_key *__key, void (*__at_exit)(void *));

_LIBCPP_THREAD_ABI_VISIBILITY
void *__libcpp_tls_get(__libcpp_tls_key __key);

_LIBCPP_THREAD_ABI_VISIBILITY
void __libcpp_tls_set(__libcpp_tls_key __key, void *__p);

#if defined(_LIBCPP_HAS_THREAD_API_PTHREAD) || \
    defined(_LIBCPP_BUILDING_THREAD_API_EXTERNAL_PTHREAD)

int __libcpp_recursive_mutex_init(__libcpp_mutex_t *__m)
{
  pthread_mutexattr_t attr;
  int __ec = pthread_mutexattr_init(&attr);
  if (__ec)
    return __ec;
  __ec = pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
  if (__ec) {
    pthread_mutexattr_destroy(&attr);
    return __ec;
  }
  __ec = pthread_mutex_init(__m, &attr);
  if (__ec) {
    pthread_mutexattr_destroy(&attr);
    return __ec;
  }
  __ec = pthread_mutexattr_destroy(&attr);
  if (__ec) {
    pthread_mutex_destroy(__m);
    return __ec;
  }
  return 0;
}

int __libcpp_mutex_lock(__libcpp_mutex_t *__m)
{
  return pthread_mutex_lock(__m);
}

int __libcpp_mutex_trylock(__libcpp_mutex_t *__m)
{
  return pthread_mutex_trylock(__m);
}

int __libcpp_mutex_unlock(__libcpp_mutex_t *__m)
{
  return pthread_mutex_unlock(__m);
}

int __libcpp_mutex_destroy(__libcpp_mutex_t *__m)
{
  return pthread_mutex_destroy(__m);
}

// Condition Variable
int __libcpp_condvar_signal(__libcpp_condvar_t *__cv)
{
  return pthread_cond_signal(__cv);
}

int __libcpp_condvar_broadcast(__libcpp_condvar_t *__cv)
{
  return pthread_cond_broadcast(__cv);
}

int __libcpp_condvar_wait(__libcpp_condvar_t *__cv, __libcpp_mutex_t *__m)
{
  return pthread_cond_wait(__cv, __m);
}

int __libcpp_condvar_timedwait(__libcpp_condvar_t *__cv, __libcpp_mutex_t *__m,
                               timespec *__ts)
{
  return pthread_cond_timedwait(__cv, __m, __ts);
}

int __libcpp_condvar_destroy(__libcpp_condvar_t *__cv)
{
  return pthread_cond_destroy(__cv);
}

// Returns non-zero if the thread ids are equal, otherwise 0
bool __libcpp_thread_id_equal(__libcpp_thread_id t1, __libcpp_thread_id t2)
{
  return pthread_equal(t1, t2) != 0;
}

// Returns non-zero if t1 < t2, otherwise 0
bool __libcpp_thread_id_less(__libcpp_thread_id t1, __libcpp_thread_id t2)
{
  return t1 < t2;
}

// Thread
int __libcpp_thread_create(__libcpp_thread_t *__t, void *(*__func)(void *),
                           void *__arg)
{
  return pthread_create(__t, 0, __func, __arg);
}

__libcpp_thread_id __libcpp_thread_get_current_id()
{
  return pthread_self();
}

__libcpp_thread_id __libcpp_thread_get_id(const __libcpp_thread_t *__t)
{
  return *__t;
}

int __libcpp_thread_join(__libcpp_thread_t *__t)
{
  return pthread_join(*__t, 0);
}

int __libcpp_thread_detach(__libcpp_thread_t *__t)
{
  return pthread_detach(*__t);
}

void __libcpp_thread_yield()
{
  sched_yield();
}

// Thread local storage
int __libcpp_tls_create(__libcpp_tls_key *__key, void (*__at_exit)(void *))
{
  return pthread_key_create(__key, __at_exit);
}

void *__libcpp_tls_get(__libcpp_tls_key __key)
{
  return pthread_getspecific(__key);
}

void __libcpp_tls_set(__libcpp_tls_key __key, void *__p)
{
  pthread_setspecific(__key, __p);
}

#endif // _LIBCPP_HAS_THREAD_API_PTHREAD

_LIBCPP_END_NAMESPACE_STD

#endif // !_LIBCPP_HAS_THREAD_API_EXTERNAL || !__libcpp_has_include(<__external_threading>)

#endif // _LIBCPP_HAS_NO_THREADS

#endif // _LIBCPP_THREADING_SUPPORT