source: XMLIO_V2/external/src/POCO/Foundation.save/URIStreamOpener.cpp @ 80

//
// URIStreamOpener.cpp
//
// $Id: //poco/1.3/Foundation/src/URIStreamOpener.cpp#2 $
//
// Library: Foundation
// Package: URI
// Module:  URIStreamOpener
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// Permission is hereby granted, free of charge, to any person or organization
// obtaining a copy of the software and accompanying documentation covered by
// this license (the "Software") to use, reproduce, display, distribute,
// execute, and transmit the Software, and to prepare derivative works of the
// Software, and to permit third-parties to whom the Software is furnished to
// do so, all subject to the following:
// 
// The copyright notices in the Software and this entire statement, including
// the above license grant, this restriction and the following disclaimer,
// must be included in all copies of the Software, in whole or in part, and
// all derivative works of the Software, unless such copies or derivative
// works are solely in the form of machine-executable object code generated by
// a source language processor.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
// SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
// FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
// ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//


#include "Poco/URIStreamOpener.h"
#include "Poco/URIStreamFactory.h"
#include "Poco/FileStreamFactory.h"
#include "Poco/URI.h"
#include "Poco/Path.h"
#include "Poco/SingletonHolder.h"
#include "Poco/Exception.h"


namespace Poco {


URIStreamOpener::URIStreamOpener()
{
        registerStreamFactory("file", new FileStreamFactory);
}


URIStreamOpener::~URIStreamOpener()
{
        for (FactoryMap::iterator it = _map.begin(); it != _map.end(); ++it)
                delete it->second;
}


std::istream* URIStreamOpener::open(const URI& uri) const
{
        FastMutex::ScopedLock lock(_mutex);

        std::string scheme;
        if (uri.isRelative())
                scheme = "file";
        else
                scheme = uri.getScheme();
        return openURI(scheme, uri);
}


std::istream* URIStreamOpener::open(const std::string& pathOrURI) const
{
        FastMutex::ScopedLock lock(_mutex);

        try
        {
                URI uri(pathOrURI);
                std::string scheme(uri.getScheme());
                FactoryMap::const_iterator it = _map.find(scheme);
                if (it != _map.end())
                        return openURI(scheme, uri);
        }
        catch (Exception&)
        {
        }
        Path path(pathOrURI, Path::PATH_GUESS);
        return openFile(path);
}


std::istream* URIStreamOpener::open(const std::string& basePathOrURI, const std::string& pathOrURI) const
{
        FastMutex::ScopedLock lock(_mutex);

        try
        {
                URI uri(basePathOrURI);
                std::string scheme(uri.getScheme());
                FactoryMap::const_iterator it = _map.find(scheme);
                if (it != _map.end())
                {
                        uri.resolve(pathOrURI);
                        return openURI(scheme, uri);
                }
        }
        catch (Exception&)
        {
        }
        Path base(basePathOrURI, Path::PATH_GUESS);
        Path path(pathOrURI, Path::PATH_GUESS);
        base.resolve(path);
        return openFile(base);
}

        
void URIStreamOpener::registerStreamFactory(const std::string& scheme, URIStreamFactory* pFactory)
{
        poco_check_ptr (pFactory);

        FastMutex::ScopedLock lock(_mutex);
        if (_map.find(scheme) == _map.end())
        {
                _map[scheme] = pFactory;
        }
        else throw ExistsException("An URIStreamFactory for the given scheme has already been registered", scheme);
}


void URIStreamOpener::unregisterStreamFactory(const std::string& scheme)
{
        FastMutex::ScopedLock lock(_mutex);
        
        FactoryMap::iterator it = _map.find(scheme);
        if (it != _map.end())
        {
                URIStreamFactory* pFactory = it->second;
                _map.erase(it);
                delete pFactory;
        }
        else throw NotFoundException("No URIStreamFactory has been registered for the given scheme", scheme);
}


bool URIStreamOpener::supportsScheme(const std::string& scheme)
{
        FastMutex::ScopedLock lock(_mutex);
        return _map.find(scheme) != _map.end();
}


URIStreamOpener& URIStreamOpener::defaultOpener()
{
        static SingletonHolder<URIStreamOpener> sh;
        return *sh.get();
}


std::istream* URIStreamOpener::openFile(const Path& path) const
{
        FileStreamFactory factory;
        return factory.open(path);
}


std::istream* URIStreamOpener::openURI(const std::string& scheme, const URI& uri) const
{
        std::string actualScheme(scheme);
        URI actualURI(uri);
        int redirects = 0;
        
        while (redirects < MAX_REDIRECTS)
        {
                try
                {
                        FactoryMap::const_iterator it = _map.find(actualScheme);
                        if (it != _map.end())
                                return it->second->open(actualURI);
                        else if (redirects > 0)
                                throw UnknownURISchemeException(actualURI.toString() + std::string("; redirected from ") + uri.toString());
                        else
                                throw UnknownURISchemeException(actualURI.toString());
                }
                catch (URIRedirection& redir)
                {
                        actualURI = redir.uri();
                        actualScheme = actualURI.getScheme();
                        ++redirects;
                }
        }
        throw IOException("Too many redirects while opening URI", uri.toString());
}


} // namespace Poco