dllaccesclient.h

linux下的一款播放器

/* ***** BEGIN LICENSE BLOCK *****
 * Source last modified: $Id: dllaccesclient.h,v 1.1.18.3 2004/07/09 01:43:51 hubbe Exp $
 * 
 * Portions Copyright (c) 1995-2004 RealNetworks, Inc. All Rights Reserved.
 * 
 * The contents of this file, and the files included with this file,
 * are subject to the current version of the RealNetworks Public
 * Source License (the "RPSL") available at
 * http://www.helixcommunity.org/content/rpsl unless you have licensed
 * the file under the current version of the RealNetworks Community
 * Source License (the "RCSL") available at
 * http://www.helixcommunity.org/content/rcsl, in which case the RCSL
 * will apply. You may also obtain the license terms directly from
 * RealNetworks.  You may not use this file except in compliance with
 * the RPSL or, if you have a valid RCSL with RealNetworks applicable
 * to this file, the RCSL.  Please see the applicable RPSL or RCSL for
 * the rights, obligations and limitations governing use of the
 * contents of the file.
 * 
 * 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 the 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 terms of either the RPSL
 * or RCSL, indicate your decision by deleting the provisions above
 * and replace them with the notice and other provisions required by
 * the GPL. If you do not delete the provisions above, a recipient may
 * use your version of this file under the terms of any one of the
 * RPSL, the RCSL or the GPL.
 * 
 * This file is part of the Helix DNA Technology. RealNetworks is the
 * developer of the Original Code and owns the copyrights in the
 * portions it created.
 * 
 * This file, and the files included with this file, is distributed
 * and made available on an 'AS IS' basis, WITHOUT WARRANTY OF ANY
 * KIND, EITHER EXPRESS OR IMPLIED, AND REALNETWORKS HEREBY DISCLAIMS
 * ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET
 * ENJOYMENT OR NON-INFRINGEMENT.
 * 
 * Technology Compatibility Kit Test Suite(s) Location:
 *    http://www.helixcommunity.org/content/tck
 * 
 * Contributor(s):
 * 
 * ***** END LICENSE BLOCK ***** */

#ifndef _DLLACCESCLIENT_H_
#define _DLLACCESCLIENT_H_

/************************************************************************
 *  Includes
 */
#include "hxcom.h"
#include "hxdllaccess.h"
#include "dllacces.h"

class DLLAccessClient
{
public:
    /////////////////////////////////////////////////////////////
    // Function: 
    //     DLLAccess
    //
    // Parameters:
    //     None
    //
    // Returns:
    //     Nothing
    //
    // Notes:
    //     Default constructor initializes internal structures for
    //     subsequent call to open()
    //
    DLLAccessClient()
	: m_pDllAccessServer(NULL)
    {
	;
    }

    /////////////////////////////////////////////////////////////
    // Function:
    //     DLLAccess
    //
    // Parameters:
    //     dllName - Name of shared library
    //
    // Returns:
    //     Nothing
    //
    // Notes:
    //     Attempts to load library dllName. If unsuccessful, m_curError
    //     is set to DLLAccess::NO_LOAD and platform specific error
    //     info is stored in m_curStringError.
    //     
    DLLAccessClient(const char* dllName, 
		    UINT16 nLibType, 
		    IUnknown* pContext)
	: m_pDllAccessServer(NULL)
    {
	open(dllName, nLibType, pContext);
    }

    //////////////////////////////////////////////////////////////
    // Function:
    //     ~DLLAccess
    //
    // Paramters:
    //     None
    //
    // Returns:
    //     Nothing
    //
    // Notes:
    //     Unloads library from memory. See 'close' below.
    //
    ~DLLAccessClient();

    ///////////////////////////////////////////////////////////////
    // Function:
    //     open(const char* dllName)
    //
    // Parameters:
    //     dllName - Name of shared library
    //
    // Returns:
    //     DLLAccess::OK if successful, else DLLAccess::NO_LOAD.
    //     Platform specific error info is stored in m_curStringError.
    //
    // Notes:
    //     
    int open(const char* dllName, 
	     UINT16 nLibType, 
	     IUnknown* pContext);

    ///////////////////////////////////////////////////////////////
    // Function:
    //     close()
    //
    // Parameters:
    //     none
    //
    // Returns:
    //     DLLAccess::OK if successful, else DLL_ACCESS::NO_LOAD.
    //
    // Notes:
    //     Shared library usage is typically reference counted by the
    //     OS: the library is actually unloaded when the reference count
    //     reaches zero. Thus this call does not guarantee that the 
    //     library will be removed from memory.
    //
    int close()
    {
	return (SUCCEEDED(m_pDllAccessServer->Close()) ? 
	    DLLAccess::DLL_OK : DLLAccess::NO_LOAD);
    }


    ///////////////////////////////////////////////////////////////
    // Function:
    //     getSymbol(const char* symName)
    //
    // Parameters:
    //     symName: symbol to retrieve from shared library
    //
    // Returns:
    //     ptr to code in library if successful, else returns NULL
    //     and m_curError is set to DLLAccess::BAD_SYMBOL.
    //
    // Notes:
    //
    void* getSymbol(const char* symName)
    {
	return m_pDllAccessServer->GetSymbol(symName);
    }

    ///////////////////////////////////////////////////////////////
    // Function:
    //     getError
    //
    // Parameters:
    //     none
    //
    // Returns:
    //     value of m_curError
    //
    // Notes:
    //     none
    //
    int getError()
    {
	return m_pDllAccessServer->GetError();
    }


    ///////////////////////////////////////////////////////////////
    // Function:
    //     getErrorString
    //
    // Parameters:
    //     none
    //
    // Returns:
    //     value of m_curErrorString
    //
    // Notes:
    //     none
    //
    const char* getErrorString() 
    { 
	return m_pDllAccessServer->GetErrorString();
    }

    ///////////////////////////////////////////////////////////////
    // Function:
    //     getDLLName
    //
    // Parameters:
    //     none
    //
    // Returns:
    //     value of m_DLLName
    //
    // Notes:
    //     none
    //
    const char* getDLLName()
    {
	return m_pDllAccessServer->GetDllName();
    }

    ///////////////////////////////////////////////////////////////
    // Function:
    //     getVersion
    //
    // Parameters:
    //     none
    //
    // Returns:
    //     value of m_Version
    //
    // Notes:
    //     none
    //
    const char* getVersion() 
    { 
	return m_pDllAccessServer->GetDllVersion();
    }

    static void CreateName(const char* short_name, 
			   const char* long_name, 
			   char* out_buf,
			   UINT32& out_buf_len)
    {
	DLLAccess::CreateName(short_name, 
			      long_name, 
			      out_buf,
			      out_buf_len);
    }

    // This overloaded version has been added to allow user to specify major and minor
    // version of the DLL name you are trying to create. It will append major and minor version
    // to the name. If you use the other function, then the major and minor versions of pnmisc
    // will be used. See pnmisc.ver in that case.
    static void CreateName(const char* short_name, 
			   const char* long_name, 
			   char* out_buf,
			   UINT32& out_buf_len, 
			   UINT32 nMajor, 
			   UINT32 nMinor)
    {
	DLLAccess::CreateName(short_name, 
			      long_name, 
			      out_buf,
			      out_buf_len,
			      nMajor,
			      nMinor);
    }

    ///////////////////////////////////////////////////////////////
    // Function:
    //     isOpen
    //
    // Parameters:
    //     none
    //
    // Returns:
    //     value of m_isOpen
    //
    // Notes:
    //     none
    //
    BOOL isOpen(void)
    { 
	return m_pDllAccessServer->IsOpen();
    }
    
private:
    IHXDllAccess* m_pDllAccessServer;
};

#endif	// _DLLACCESCLIENT_H_