Click here to Skip to main content
15,891,848 members
Search within:


Articles / Desktop Programming / MFC
 

Multi platform plug-in development made easy!

Rate me:
Please Sign up or sign in to vote.
4.04/5 (25 votes)
7 Mar 20065 min read 101.6K   1.9K   63  
How to use and develop plug-ins for multiple platforms.
 
/*!

\section terms_of_use Terms of Use

libspl - the simple plugin layer library.
Copyright (C) 2004 Andreas Loeffler and Ren� Stuhr (www.unitedbytes.de).

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

\section author Author
Andreas Loeffler (www.unitedbytes.de)

*/

//---------------------------------------------------------------------------------------------------------------------------
/// @file		spl_pluginserver_win32.cpp
/// @version	1.0
/// @author		Andreas Loeffler
//---------------------------------------------------------------------------------------------------------------------------

#ifndef		__SPL_PLATFORM_H__
#include	"spl_platform.h"
#endif


#if			SPL_PLATFORM == SPL_PLATFORM_WIN32

#define		_WIN32_WINNT 0x0400

#ifndef		_WINDOWS_
#include	<windows.h>
#endif

#ifndef		__SPL_PLUGINSERVER_WIN32_H__
#include	"spl_pluginserver_win32.h"
#endif

#ifndef		__SPL_THREADLOCK_H__
#include	"spl_threadlock.h"
#endif

//
// Disable warning messages
//
#pragma warning( disable : 4311 4312 4267 )  

slcPluginServer::slcPluginServer( void )
{

}

slcPluginServer::~slcPluginServer( void )
{
	if( this->GetLoadedPlugins() > 0 )
		this->UnloadAllPlugins();
}

slcPluginInfo slcPluginServer::GetPluginInfo( const long a_lIndex )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	if( ( a_lIndex < 0 ) ||
		( a_lIndex > ( long )this->m_mapPluginInfos.size() ) )
	{
		slcPluginInfo invalidInfo;
		return invalidInfo;
	}

	this->itIds  = this->m_mapPluginIds.find( a_lIndex ); 
	if( this->itIds != this->m_mapPluginIds.end() )
	{
		SPL_INFO_FUNC pInfoFunc = ( SPL_INFO_FUNC )::GetProcAddress( ( HMODULE )( SPL_BITTYPE )this->itIds->second, 	SPL_GETINFO_NAME );
		if( NULL != pInfoFunc )
		{
			slcPluginInfo plugInfo = *pInfoFunc();
			this->m_mapPluginInfos.insert( pair<long, slcPluginInfo>( this->m_mapPluginInfos.size() , plugInfo ) );
		}
		else
		{
			//
			// INFO FUNCTION NOT LOADED, INSERT DUMMY ENTRY TO AVOID ASYNCRON MAPS 
			//
			slcPluginInfo nullInfo;
			this->m_mapPluginInfos.insert( pair<long, slcPluginInfo>( this->m_mapPluginInfos.size(), nullInfo ) );
		}
	}

	return this->m_mapPluginInfos[ a_lIndex ];
}

void slcPluginServer::GetAllPluginInfos( void )
{
	long l = 0;

	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	for( this->itIds  = this->m_mapPluginIds.begin(); 
		 this->itIds != this->m_mapPluginIds.end(); this->itIds++ )
	{
		SPL_INFO_FUNC pInfoFunc = ( SPL_INFO_FUNC )::GetProcAddress( ( HMODULE )( SPL_BITTYPE )this->itIds->second, 
																	 SPL_GETINFO_NAME );
		if( NULL != pInfoFunc )
		{
			slcPluginInfo plugInfo = *pInfoFunc();
			this->m_mapPluginInfos.insert( pair<long, slcPluginInfo>( l++, plugInfo ) );
		}
		else
		{
			//
			// INFO FUNCTION NOT LOADED, INSERT DUMMY ENTRY TO AVOID ASYNCRON MAPS 
			//
			slcPluginInfo nullInfo;
			this->m_mapPluginInfos.insert( pair<long, slcPluginInfo>( l++, nullInfo ) );
		}
	}
}

long slcPluginServer::LoadAllPlugins( const string&		   a_strPath, 
									  const string&		   a_strWildcard, 
									  const	slcPluginArgs* a_pPluginArgs )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	WIN32_FIND_DATA FindData;
	string strWildcard;

	if( a_strWildcard.empty() )
		strWildcard = "*.dll";
	else
		strWildcard = a_strWildcard;

	const slcPluginArgs* pPluginArgs = a_pPluginArgs; 

	if( NULL == pPluginArgs )
		pPluginArgs = &this->m_nullArgs;

	::SetCurrentDirectory( a_strPath.c_str() );
	HANDLE hDirectory = ::FindFirstFileEx( strWildcard.c_str(), FindExInfoStandard, 
		&FindData, FindExSearchNameMatch, NULL, 0 );

	if( hDirectory != INVALID_HANDLE_VALUE )
	{
		do {
			if( ( strcmp( FindData.cFileName, "." ) != 0 ) &&
				( strcmp( FindData.cFileName, ".." ) != 0 ) )
			{
				HMODULE hModule = ::LoadLibrary( FindData.cFileName );
				if ( NULL != hModule )
				{ 
					SPL_INIT_FUNC pInitFunc =( SPL_INIT_FUNC )::GetProcAddress( ( HINSTANCE )hModule, 
																				SPL_INIT_NAME );
					if( NULL != pInitFunc )
					{
						pInitFunc( pPluginArgs );
						this->m_mapPluginIds.insert( pair< long, SPL_BITTYPE >( ( long )this->m_mapPluginIds.size(), ( SPL_BITTYPE )hModule ) );
					}
				}
			}	
		} 
		while( ::FindNextFile( hDirectory, &FindData ) );

		::FindClose( hDirectory );
	}

	return ( long )this->m_mapPluginIds.size();
}

long slcPluginServer::LoadPlugin( const string& a_strFileName, const slcPluginArgs* a_pPluginArgs )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	if( a_strFileName.empty() )
		return -2;

	const slcPluginArgs* pPluginArgs = a_pPluginArgs; 

	if( NULL == pPluginArgs )
		pPluginArgs = &this->m_nullArgs;

	HMODULE hModule = ::LoadLibrary( a_strFileName.c_str() );

	if ( NULL != hModule )
	{ 
		SPL_INIT_FUNC pInitFunc =( SPL_INIT_FUNC )::GetProcAddress( ( HINSTANCE )hModule, 
																	SPL_INIT_NAME );

		this->m_mapPluginIds.insert( pair< long, SPL_BITTYPE >( ( long )this->m_mapPluginIds.size(), ( SPL_BITTYPE )hModule ) );
		if( NULL != pInitFunc )
		{
			return pInitFunc( pPluginArgs ) ? 1 : 0;
		}

		return -1;
	}

	return -2;
}

bool slcPluginServer::UnloadPlugin( const long a_lIndex, const slcPluginArgs* a_pPluginArgs )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	if( ( a_lIndex < 0 ) ||
		( a_lIndex > ( long )this->m_mapPluginInfos.size() ) )
	{
		return false;
	}

	const slcPluginArgs* pPluginArgs = a_pPluginArgs; 

	if( NULL == pPluginArgs )
		pPluginArgs = &this->m_nullArgs;

	this->itIds = this->m_mapPluginIds.find( a_lIndex );

	if( this->itIds != this->m_mapPluginIds.end() )
	{
		SPL_SHUTDOWN_FUNC pShutdownFunc =( SPL_SHUTDOWN_FUNC )::GetProcAddress( ( HINSTANCE )this->itIds->second, 
																				SPL_SHUTDOWN_NAME );
		if( NULL != pShutdownFunc )
		{
			pShutdownFunc( pPluginArgs );
		}

		//
		// UNLOAD LIBRARY
		//
		::FreeLibrary( ( HMODULE )this->itIds->second ); 

		//
		// REMOVE LIBRARY FROM ID-MAP AND INFO-MAP
		//
		this->m_mapPluginInfos.erase( this->itIds->first );
		this->m_mapPluginIds.erase( this->itIds->first );

		//
		// REFRESH ALL MAP IDS (CREATE NEW KEYS FOR ALL VALUES)
		//
		int i = 0;

		long lSize = this->m_mapPluginIds.size();
		map< long, SPL_BITTYPE > tempIds;
		map< long, SPL_BITTYPE >::iterator itTempIds;
		
		tempIds = this->m_mapPluginIds;
		this->m_mapPluginIds.clear();
		itTempIds = tempIds.begin();
		
		for( i = 0 ; i < lSize; i++, itTempIds++ )
			this->m_mapPluginIds.insert( pair<long, SPL_BITTYPE> (i, itTempIds->second ) );

		lSize = this->m_mapPluginInfos.size();
		map< long, slcPluginInfo > tempInfos;
		map< long, slcPluginInfo >::iterator itTempInfos;
		
		tempInfos = this->m_mapPluginInfos; 
		this->m_mapPluginInfos.clear();
		itTempInfos = tempInfos.begin();
		
		for( i = 0 ; i < lSize; i++, itTempInfos++ )
			this->m_mapPluginInfos.insert( pair<long, slcPluginInfo> (i, itTempInfos->second ) );

		return true;
	}

	return false;
}

void slcPluginServer::UnloadAllPlugins( const slcPluginArgs* a_pPluginArgs )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	long lCount =  ( long )this->m_mapPluginIds.size();
	for( long l = 0; l < lCount;  l++ )
	{
		this->UnloadPlugin( 0, a_pPluginArgs );
	}

	this->Clear();
}

bool slcPluginServer::RunPlugin( long a_lIndex, const slcPluginArgs* a_pPluginArgs )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	const slcPluginArgs* pPluginArgs = a_pPluginArgs; 

	if( NULL == pPluginArgs )
		pPluginArgs = &this->m_nullArgs;

	if( ( a_lIndex < 0 ) ||
		( a_lIndex > ( long )this->m_mapPluginInfos.size() ) )
	{
		return false;
	}

	this->itIds = this->m_mapPluginIds.find( a_lIndex );
	if( this->itIds != this->m_mapPluginIds.end() )
	{
		SPL_RUN_FUNC pRunFunc =( SPL_RUN_FUNC )::GetProcAddress( ( HINSTANCE )this->itIds->second, 
																 SPL_RUN_NAME );
		if( NULL != pRunFunc )
		{
			return pRunFunc( pPluginArgs );
		}
	}

	return false;
}

long slcPluginServer::RunAllPlugins( const slcPluginArgs* a_pPluginArgs )
{
	//
	// LOCKS OBJECT FOR EXCLUSIVE USE, UNLOCKS AUTOMATICALLY AT THE END OF FUNCTION.
	// IMPLICIT USAGE.
	//
	slcThreadLock threadLock( this, true );

	long lPluginsRunned = 0;
	const slcPluginArgs* pPluginArgs = a_pPluginArgs; 

	if( NULL == pPluginArgs )
		pPluginArgs = &this->m_nullArgs;

	if( this->m_mapPluginIds.empty() )
		return 0;

	for( long l = 0; l < ( long )this->m_mapPluginIds.size(); l++ )
	{
		if( this->RunPlugin( l, pPluginArgs ) )
			lPluginsRunned++;
	}

	return lPluginsRunned;
}

long slcPluginServer::Refresh( const string&	    a_strPath, 
							   const string&	    a_strWildcard, 
							   const slcPluginArgs* a_pPluginShutdownArgs, 
							   const slcPluginArgs*	a_pPluginInitArgs )
{
	this->UnloadAllPlugins( a_pPluginShutdownArgs );

	//
	// Lock this object for exclusive use.
	// Explicitly usage.
	//
	slcThreadLock threadLock( this );

	threadLock.Lock();
	this->Clear();
	threadLock.Unlock();

	return( this->LoadAllPlugins( a_strPath, a_strWildcard, a_pPluginInitArgs ) ); 
}

//
// Enable warning messages
//
#pragma warning( default : 4311 4312 4267 )  


#endif	//	SPL_PLATFORM_WIN32

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here


Written By
Andreas Loeffler
Web Developer
Germany Germany
I was born in 1982 near Stuttgart / Germany and began my first steps in programming computers at the age of only nine years on an old Commodore CBM 7072. In 2002 I finished my education as IT specialist for software engineering and did my civillian service afterwards. Currently I'm working as leader of the software division in a bigger company located in south west Germany, mainly on software development and research projects for multimedia terminals and user recognition/verification systems.

Comments and Discussions

Permalink
Advertise
Privacy
Cookies
Terms of Use
Layout: fixed | fluid

Posted 8 May 2004

Article Copyright 2004 by Andreas Loeffler
Everything else Copyright © CodeProject, 1999-2024

Web03 2.8:2024-04-02:1