httpfilesys.cpp

著名的 helix realplayer 基于手机 symbian 系统的 播放器全套源代码

/* ***** BEGIN LICENSE BLOCK ***** 
 * Version: RCSL 1.0/RPSL 1.0 
 *  
 * Portions Copyright (c) 1995-2002 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 
 * Version 1.0 (the "RPSL") available at 
 * http://www.helixcommunity.org/content/rpsl unless you have licensed 
 * the file under the RealNetworks Community Source License Version 1.0 
 * (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.  
 *  
 * 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 ***** */ 

/****************************************************************************
 * Defines
 */
#define   INITGUID     /* Interface ID's */


/****************************************************************************
 * Includes
 */
#include "hlxclib/string.h" /* strcpy */

#include "hxtypes.h" 
#include "hxver.h"    /* HXVER_COPYRIGHT */
#include "hxcom.h"    /* IUnknown */
#include "hxcomm.h"   /* IHXCommonClassFactory */
#include "ihxpckts.h" /* IHXValues */
#include "hxprefs.h" 

#include "httpfilesys.h" /* CHTTPFileSystem */
#include "httpfileobj.h" /* CHTTPFileObject */
#include "hxcache2.h"

#include "httpfilesys.ver" /* version info */

#include "debug.h"

#define D_HTTP_FS 0x1000000

#undef INITGUID


/****************************************************************************
 * 
 *  Function:
 * 
 *	HXCreateInstance()
 * 
 *  Purpose:
 * 
 *	Function implemented by all plugin DLL's to create an instance of 
 *	any of the objects supported by the DLL. This method is similar to 
 *	Window's CoCreateInstance() in its purpose, except that it only 
 *	creates objects from this plugin DLL.
 *
 *	NOTE: Aggregation is never used. Therefore and outer unknown is
 *	not passed to this function, and you do not need to code for this
 *	situation.
 * 
 */
STDAPI ENTRYPOINT(HXCREATEINSTANCE)(IUnknown** ppFileSystemObj)
{
    DPRINTF(D_HTTP_FS, ("HTTPFileSystem HXCREATEINSTANCE()\n"));

    HX_RESULT res = HXR_OUTOFMEMORY;

    *ppFileSystemObj = (IUnknown*)(IHXPlugin*)new CHXHTTPFileSystem();

    if (*ppFileSystemObj != NULL)
    {
	(*ppFileSystemObj)->AddRef();
	res = HXR_OK;
    }
    
    return res;
}

STDAPI ENTRYPOINT(CanUnload2)(void)
{
    return (CHXBaseCountingObject::ObjectsActive() > 0 ? HXR_FAIL : HXR_OK);
}

// CHXHTTPFileSystem Class Methods

/****************************************************************************
 *  CHXHTTPFileSystem static variables
 *
 *  These variables are passed to the Helix core to provide information about
 *  this plug-in. They are required to be static in order to remain valid
 *  for the lifetime of the plug-in.
 */
const char* const CHXHTTPFileSystem::zm_pDescription = "Helix HTTP File System";
const char* const CHXHTTPFileSystem::zm_pCopyright   = HXVER_COPYRIGHT;
const char* const CHXHTTPFileSystem::zm_pMoreInfoURL = HXVER_MOREINFO;
const char* const CHXHTTPFileSystem::zm_pShortName   = "hx-http";
const char* const CHXHTTPFileSystem::zm_pProtocol    = FILE_SYS_PROTOCOL;


/****************************************************************************
 *  CHXHTTPFileSystem::CHXHTTPFileSystem
 *
 *  Constructor
 */
CHXHTTPFileSystem::CHXHTTPFileSystem(void)
    : m_RefCount      (0),
      m_pContext     (NULL),
      m_pOptions     (NULL)
{
    DPRINTF(D_HTTP_FS, ("CHXHTTPFileSystem()\n"));
}


/****************************************************************************
 *  CHXHTTPFileSystem::~CHXHTTPFileSystem
 *
 *  Destructor. Be sure to release all outstanding references to objects.
 */
CHXHTTPFileSystem::~CHXHTTPFileSystem(void)
{
    DPRINTF(D_HTTP_FS, ("~CHXHTTPFileSystem()\n"));

    HX_RELEASE(m_pContext);
    HX_RELEASE(m_pOptions);
}


// IHXFileSystemObject Interface Methods

/****************************************************************************
 *  IHXFileSystemObject::GetFileSystemInfo
 *
 *  This routine returns crucial information required to associate this
 *  plug-in with a given protocol. This information tells the core which
 *  File System plug-in to use for a particular protocol. For example, in the
 *  URL: "file://myfile.txt", the protocol would be "file". This routine is
 *  called when the Helix core application is launched.
 */
STDMETHODIMP
CHXHTTPFileSystem::GetFileSystemInfo(REF(const char*) pShortName,
				     REF(const char*) pProtocol)
{
    DPRINTF(D_HTTP_FS, ("GetFileSystemInfo()\n"));

    pShortName = zm_pShortName;
    pProtocol  = zm_pProtocol;

    return HXR_OK;
}


/****************************************************************************
 *  IHXFileSystemObject::InitFileSystem
 *
 *  This routine performs any additional initialization steps required for
 *  the file system.  It is called prior to the CreatFile() request. Any
 *  options provided usually refer to mounting options related to the server,
 *  such as base path or authentication preferences. 
 */
STDMETHODIMP 
CHXHTTPFileSystem::InitFileSystem(IHXValues*  options )
{
    DPRINTF(D_HTTP_FS, ("InitFileSystem()\n"));

    if(options)
    {
        m_pOptions = options;
        m_pOptions->AddRef();
    }
	
    return HXR_OK;
}


/****************************************************************************
 *  IHXFileSystemObject::CreateFile
 *
 *  This routine creates a new File Object which handles all of the file I/O
 *  functionality of this class. This File Object is eventually handed off
 *  to a File Format plug-in which handles file I/O through this File Object.
 *  This method is called called when an URL with a protocol associated with
 *  this plug-in is opened.
 */
STDMETHODIMP
CHXHTTPFileSystem::CreateFile(IUnknown** ppFileObject)
{
    DPRINTF(D_HTTP_FS, ("CreateFile()\n"));

    HX_RESULT res = HXR_OUTOFMEMORY;

    // Create a new File Object which implements the file I/O methods
    CHXHTTPFileObject* pFileObj = new CHXHTTPFileObject(m_pContext, m_pOptions);

    if (pFileObj != NULL)
    {	
	pFileObj->QueryInterface(IID_IUnknown, (void**)ppFileObject);

	res = (pFileObj != NULL) ? HXR_OK : HXR_UNEXPECTED;
    }

    return res;
}


/****************************************************************************
 *  IHXFileSystemObject::CreateDir
 *
 *  This routine is analagous to CreatFile, except directories instead of
 *  files are of concern. It is not implemented in this plugin.
 */
STDMETHODIMP
CHXHTTPFileSystem::CreateDir(IUnknown** /* ppDirectoryObject */)
{
    DPRINTF(D_HTTP_FS, ("CreateDir()\n"));

    return HXR_NOTIMPL;
}


// IHXPlugin Interface Methods

/****************************************************************************
 *  IHXPlugin::GetPluginInfo
 *
 *  This routine returns descriptive information about the plug-in, most
 *  of which is used in the About box of the user interface. It is called
 *  when the Helix core application is launched.
 */
STDMETHODIMP
CHXHTTPFileSystem::GetPluginInfo(REF(BOOL)        bLoadMultiple,
				 REF(const char*) pDescription,
				 REF(const char*) pCopyright,
				 REF(const char*) pMoreInfoURL,
				 REF(UINT32)      versionNumber)
{
    DPRINTF(D_HTTP_FS, ("GetPluginInfo()\n"));

    bLoadMultiple = TRUE;
    pDescription  = zm_pDescription;
    pCopyright    = zm_pCopyright;
    pMoreInfoURL  = zm_pMoreInfoURL;
    versionNumber = TARVER_ULONG32_VERSION;

    return HXR_OK;
}


/****************************************************************************
 *  IHXPlugin::InitPlugin
 *
 *  This routine performs initialization steps such as determining if
 *  required interfaces are available. It is called when the Helix core 
 *  application is launched, and whenever an URL with a protocol associated
 *  with this plug-in is opened.
 */
STDMETHODIMP
CHXHTTPFileSystem::InitPlugin(IUnknown* pContext)
{
    DPRINTF(D_HTTP_FS, ("InitPlugin()\n"));

    HX_RESULT res = HXR_OK;

    if (pContext == NULL)
    {
	res = HXR_NOINTERFACE;
    }
    else
    {
        m_pContext = pContext;
        m_pContext->AddRef();
    }

    return res;
}


// IUnknown COM Interface Methods

/****************************************************************************
 *  IUnknown::AddRef
 *
 *  This routine increases the object reference count in a thread safe
 *  manner. The reference count is used to manage the lifetime of an object.
 *  This method must be explicitly called by the user whenever a new
 *  reference to an object is used.
 */
STDMETHODIMP_(UINT32) CHXHTTPFileSystem::AddRef(void)
{
    return InterlockedIncrement(&m_RefCount);
}


/****************************************************************************
 *  IUnknown::Release
 *
 *  This routine decreases the object reference count in a thread safe
 *  manner, and deletes the object if no more references to it exist. It must
 *  be called explicitly by the user whenever an object is no longer needed.
 */
STDMETHODIMP_(UINT32) CHXHTTPFileSystem::Release(void)
{
    if (InterlockedDecrement(&m_RefCount) > 0)
    {
	return m_RefCount;
    }

    delete this;
    return 0;
}


/****************************************************************************
 *  IUnknown::QueryInterface
 *
 *  This routine indicates which interfaces this object supports. If a given
 *  interface is supported, the object's reference count is incremented, and
 *  a reference to that interface is returned. Otherwise a NULL object and
 *  error code are returned. This method is called by other objects to
 *  discover the functionality of this object.
 */
STDMETHODIMP CHXHTTPFileSystem::QueryInterface(REFIID interfaceID,
					       void** ppInterfaceObj)
{
    // By definition all COM objects support the IUnknown interface
    if (IsEqualIID(interfaceID, IID_IUnknown))
    {
	AddRef();
	*ppInterfaceObj = (IUnknown*)(IHXPlugin*)this;
	return HXR_OK;
    }
    // IHXPlugin interface is supported
    else if (IsEqualIID(interfaceID, IID_IHXPlugin))
    {
	AddRef();
	*ppInterfaceObj = (IHXPlugin*)this;
	return HXR_OK;
    }
    // IHXFileSystemObject interface is supported
    else if (IsEqualIID(interfaceID, IID_IHXFileSystemObject))
    {
	AddRef();
	*ppInterfaceObj = (IHXFileSystemObject*)this;
	return HXR_OK;
    }

    // No other interfaces are supported
    *ppInterfaceObj = NULL;
    return HXR_NOINTERFACE;
}