// -*- C++ -*-
//  Copyright (C) 2010-2017, Vaclav Haisman. All rights reserved.
//  
//  Redistribution and use in source and binary forms, with or without modifica-
//  tion, are permitted provided that the following conditions are met:
//  
//  1. Redistributions of  source code must  retain the above copyright  notice,
//     this list of conditions and the following disclaimer.
//  
//  2. Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//  
//  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
//  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
//  FITNESS  FOR A PARTICULAR  PURPOSE ARE  DISCLAIMED.  IN NO  EVENT SHALL  THE
//  APACHE SOFTWARE  FOUNDATION  OR ITS CONTRIBUTORS  BE LIABLE FOR  ANY DIRECT,
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//  DING, BUT NOT LIMITED TO, PROCUREMENT  OF SUBSTITUTE GOODS OR SERVICES; LOSS
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#ifndef LOG4CPLUS_THREAD_IMPL_TLS_H
#define LOG4CPLUS_THREAD_IMPL_TLS_H

#include <log4cplus/config.hxx>

#if defined (LOG4CPLUS_HAVE_PRAGMA_ONCE)
#pragma once
#endif

#include <new>
#include <cassert>
#include <system_error>

#if ! defined (INSIDE_LOG4CPLUS)
#  error "This header must not be be used outside log4cplus' implementation files."
#endif

#ifdef LOG4CPLUS_USE_PTHREADS
#  include <pthread.h>

#elif defined (LOG4CPLUS_USE_WIN32_THREADS)
#  include <log4cplus/config/windowsh-inc.h>

#elif defined (LOG4CPLUS_SINGLE_THREADED)
#  include <vector>

#endif


namespace log4cplus { namespace thread { namespace impl {


typedef void * tls_value_type;

#ifdef LOG4CPLUS_USE_PTHREADS
typedef pthread_key_t * tls_key_type;
typedef void (* tls_init_cleanup_func_type)(void *);

#elif defined (LOG4CPLUS_USE_WIN32_THREADS)
typedef DWORD tls_key_type;
typedef PFLS_CALLBACK_FUNCTION tls_init_cleanup_func_type;

#elif defined (LOG4CPLUS_SINGLE_THREADED)
typedef std::size_t tls_key_type;
typedef void (* tls_init_cleanup_func_type)(void *);

#endif


inline tls_key_type tls_init (tls_init_cleanup_func_type);
inline tls_value_type tls_get_value (tls_key_type);
inline void tls_set_value (tls_key_type, tls_value_type);
inline void tls_cleanup (tls_key_type);


#if defined (LOG4CPLUS_USE_PTHREADS)
tls_key_type
tls_init (tls_init_cleanup_func_type cleanupfunc)
{
    pthread_key_t * key = new pthread_key_t;
    int ret = pthread_key_create (key, cleanupfunc);
    if (LOG4CPLUS_UNLIKELY (ret != 0))
        throw std::system_error(ret, std::system_category (),
            "pthread_key_create() failed");
    return key;
}


tls_value_type
tls_get_value (tls_key_type key)
{
    return pthread_getspecific (*key);
}


void
tls_set_value (tls_key_type key, tls_value_type value)
{
    pthread_setspecific(*key, value);
}


void
tls_cleanup (tls_key_type key)
{
    pthread_key_delete (*key);
    delete key;
}


#elif defined (LOG4CPLUS_USE_WIN32_THREADS)
tls_key_type
tls_init (tls_init_cleanup_func_type cleanupfunc)
{
    DWORD const slot = FlsAlloc (cleanupfunc);
    if (LOG4CPLUS_UNLIKELY (slot == FLS_OUT_OF_INDEXES))
    {
        DWORD const eno = GetLastError ();
        throw std::system_error (static_cast<int>(eno),
            std::system_category (), "FlsAlloc() failed");
    }
    return slot;
}


tls_value_type tls_get_value (tls_key_type k)
{
    return FlsGetValue (k);
}


void
tls_set_value (tls_key_type k, tls_value_type value)
{
    FlsSetValue (k, value);
}


void
tls_cleanup (tls_key_type k)
{
    FlsFree (k);
}


#elif defined (LOG4CPLUS_SINGLE_THREADED)
extern std::vector<tls_value_type> * tls_single_threaded_values;


tls_key_type
tls_init (tls_init_cleanup_func_type)
{
    if (! tls_single_threaded_values)
        tls_single_threaded_values = new std::vector<tls_value_type>;
    tls_key_type key = tls_single_threaded_values->size ();
    tls_single_threaded_values->resize (key + 1);
    return key;
}


tls_value_type
tls_get_value (tls_key_type k)
{
    assert (k < tls_single_threaded_values->size ());
    return (*tls_single_threaded_values)[k];
}


void
tls_set_value (tls_key_type k, tls_value_type val)
{
    assert (k < tls_single_threaded_values->size ());
    (*tls_single_threaded_values)[k] = val;
}


void
tls_cleanup (tls_key_type k)
{
    assert (k < tls_single_threaded_values->size ());
    (*tls_single_threaded_values)[k] = 0;
}

#endif


} } } // namespace log4cplus { namespace thread { namespace impl {

#endif // LOG4CPLUS_THREAD_IMPL_TLS_H
