/*
 *
 * Copyright (c) 2006 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
#include <iostream>
#include "APRBase.h"
#include "QpidError.h"

using namespace qpid::concurrent;

APRBase* APRBase::instance = 0;

APRBase* APRBase::getInstance(){
    if(instance == 0){
	instance = new APRBase();
    }
    return instance;
}


APRBase::APRBase() : count(0){
    apr_initialize();
    CHECK_APR_SUCCESS(apr_pool_create(&pool, 0));
    CHECK_APR_SUCCESS(apr_thread_mutex_create(&mutex, APR_THREAD_MUTEX_NESTED, pool));
}

APRBase::~APRBase(){
    CHECK_APR_SUCCESS(apr_thread_mutex_destroy(mutex));
    apr_pool_destroy(pool);
    apr_terminate();  
}

bool APRBase::_increment(){
    bool deleted(false);
    CHECK_APR_SUCCESS(apr_thread_mutex_lock(mutex));
    if(this == instance){
	count++;
    }else{
	deleted = true;
    }
    CHECK_APR_SUCCESS(apr_thread_mutex_unlock(mutex));
    return !deleted;
}

void APRBase::_decrement(){
    APRBase* copy = 0;
    CHECK_APR_SUCCESS(apr_thread_mutex_lock(mutex));
    if(--count == 0){
	copy = instance;
	instance = 0;
    }
    CHECK_APR_SUCCESS(apr_thread_mutex_unlock(mutex));
    if(copy != 0){
	delete copy;
    }
}

void APRBase::increment(){
    int count = 0;
    while(count++ < 2 && !getInstance()->_increment()){
        std::cout << "WARNING: APR initialization triggered concurrently with termination." << std::endl;
    }
}

void APRBase::decrement(){
    getInstance()->_decrement();
}

void qpid::concurrent::check(apr_status_t status, const std::string& file, const int line){
    if (status != APR_SUCCESS){
        const int size = 50;
        char tmp[size];
        std::string msg(apr_strerror(status, tmp, size));
        throw QpidError(APR_ERROR + ((int) status), msg, file, line);
    }
}

std::string qpid::concurrent::get_desc(apr_status_t status){
    const int size = 50;
    char tmp[size];
    return std::string(apr_strerror(status, tmp, size));
}