environment.h

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/** @file
 *  @author Bram de Greve (bram@cocamware.com)
 *  @author Tom De Muer (tom@cocamware.com)
 *
 *  *** BEGIN LICENSE INFORMATION ***
 *  
 *  The contents of this file are subject to the Common Public Attribution License 
 *  Version 1.0 (the "License"); you may not use this file except in compliance with 
 *  the License. You may obtain a copy of the License at 
 *  http://lass.sourceforge.net/cpal-license. The License is based on the 
 *  Mozilla Public License Version 1.1 but Sections 14 and 15 have been added to cover 
 *  use of software over a computer network and provide for limited attribution for 
 *  the Original Developer. In addition, Exhibit A has been modified to be consistent 
 *  with Exhibit B.
 *  
 *  Software distributed under the License is distributed on an "AS IS" basis, WITHOUT 
 *  WARRANTY OF ANY KIND, either express or implied. See the License for the specific 
 *  language governing rights and limitations under the License.
 *  
 *  The Original Code is LASS - Library of Assembled Shared Sources.
 *  
 *  The Initial Developer of the Original Code is Bram de Greve and Tom De Muer.
 *  The Original Developer is the Initial Developer.
 *  
 *  All portions of the code written by the Initial Developer are:
 *  Copyright (C) 2004-2026 the Initial Developer.
 *  All Rights Reserved.
 *  
 *  Contributor(s):
 *
 *  Alternatively, the contents of this file may be used under the terms of the 
 *  GNU General Public License Version 2 or later (the GPL), in which case the 
 *  provisions of GPL are applicable instead of those above.  If you wish to allow use
 *  of your version of this file only under the terms of the GPL and not to allow 
 *  others to use your version of this file under the CPAL, indicate your decision by 
 *  deleting the provisions above and replace them with the notice and other 
 *  provisions required by the GPL License. If you do not delete the provisions above,
 *  a recipient may use your version of this file under either the CPAL or the GPL.
 *  
 *  *** END LICENSE INFORMATION ***
 */
 
 
#ifndef LASS_GUARDIAN_OF_INCLUSION_UTIL_IMPL_ENVIRONMENT_H
#define LASS_GUARDIAN_OF_INCLUSION_UTIL_IMPL_ENVIRONMENT_H
 
#include "util_common.h"
 
namespace lass
{
namespace util
{
namespace impl
{
 
LASS_DLL const std::string LASS_CALL lass_getenv(const std::string& name);
LASS_DLL void LASS_CALL lass_putenv(const std::string& name, const std::string& value);
 
template <typename T>
struct Environment
{
    static const T get(const std::string& name)
    {
        return stringCast<T>(lass_getenv(name));
    }
    static void put(const std::string& name, typename CallTraits<T>::TParam value)
    {
        lass_putenv(name, stringCast<std::string>(value));
    }
};
 
template <>
struct Environment<std::string>
{
    static const std::string get(const std::string& name)
    {
        return lass_getenv(name);
    }
    static void put(const std::string& name, const std::string& value)
    {
        lass_putenv(name, value);
    }
};
 
}
 
/** Get environment variable and cast it to type T
 *
 *  @param name environment variable name to be retrieved
 *
 *  @throw KeyError if environment variable doesn't exist
 *  @throw BadStringCast if the value can't be cast to type T
 */
template <typename T>
const T getEnvironment(const std::string& name)
{   
    return impl::Environment<typename CallTraits<T>::TValue>::get(name);
}
 
/** Put value in environment variable
 *
 *  @param name environment variable name to be stored
 *  @param value environment variable value to be stored, will be cast to a string
 *
 *  @throw BadStringCast if the value can't be cast to std::string
 */
template <typename T>
void putEnvironment(const std::string& name, const T& value)
{
    impl::Environment<typename CallTraits<T>::TValue>::put(name, value);
}
 
}
}
 
#endif
 
// EOF