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// Copyright (C) 2007 Anthony Williams
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
#include <boost/thread/detail/config.hpp>
#ifdef BOOST_THREAD_ONCE_ATOMIC
#include "./once_atomic.cpp"
#else
#define __STDC_CONSTANT_MACROS
#include <boost/thread/once.hpp>
#include <boost/assert.hpp>
#include <boost/throw_exception.hpp>
#include <pthread.h>
#include <stdlib.h>
#include <memory>
#include <string.h> // memcmp.
namespace boost
{
namespace thread_detail
{
BOOST_THREAD_DECL uintmax_atomic_t once_global_epoch=BOOST_THREAD_DETAIL_UINTMAX_ATOMIC_MAX_C;
BOOST_THREAD_DECL pthread_mutex_t once_epoch_mutex=PTHREAD_MUTEX_INITIALIZER;
BOOST_THREAD_DECL pthread_cond_t once_epoch_cv = PTHREAD_COND_INITIALIZER;
namespace
{
pthread_key_t epoch_tss_key;
pthread_once_t epoch_tss_key_flag=PTHREAD_ONCE_INIT;
extern "C"
{
static void delete_epoch_tss_data(void* data)
{
free(data);
}
static void create_epoch_tss_key()
{
BOOST_VERIFY(!pthread_key_create(&epoch_tss_key,delete_epoch_tss_data));
}
}
#if defined BOOST_THREAD_PATCH
const pthread_once_t pthread_once_init_value=PTHREAD_ONCE_INIT;
struct BOOST_THREAD_DECL delete_epoch_tss_key_on_dlclose_t
{
delete_epoch_tss_key_on_dlclose_t()
{
}
~delete_epoch_tss_key_on_dlclose_t()
{
if(memcmp(&epoch_tss_key_flag, &pthread_once_init_value, sizeof(pthread_once_t)))
{
void* data = pthread_getspecific(epoch_tss_key);
if (data)
delete_epoch_tss_data(data);
pthread_key_delete(epoch_tss_key);
}
}
};
delete_epoch_tss_key_on_dlclose_t delete_epoch_tss_key_on_dlclose;
#endif
}
uintmax_atomic_t& get_once_per_thread_epoch()
{
BOOST_VERIFY(!pthread_once(&epoch_tss_key_flag,create_epoch_tss_key));
void* data=pthread_getspecific(epoch_tss_key);
if(!data)
{
data=malloc(sizeof(thread_detail::uintmax_atomic_t));
if(!data) BOOST_THROW_EXCEPTION(std::bad_alloc());
BOOST_VERIFY(!pthread_setspecific(epoch_tss_key,data));
*static_cast<thread_detail::uintmax_atomic_t*>(data)=BOOST_THREAD_DETAIL_UINTMAX_ATOMIC_MAX_C;
}
return *static_cast<thread_detail::uintmax_atomic_t*>(data);
}
}
}
#endif //