cdevicecache.cpp

PGP8.0源码 请认真阅读您的文件包然后写出其具体功能

/*____________________________________________________________________________
		Copyright (C) 2002 PGP Corporation
        All rights reserved.

        $Id: CDeviceCache.cpp,v 1.3 2002/08/06 20:09:31 dallen Exp $
____________________________________________________________________________*/

#include "pgpClassesConfig.h"

#include "CString.h"

#include "CDevice.h"
#include "CUnicodeString.h"

#include "CDeviceCache.h"

_USING_PGP

// Types

struct CDeviceCache::CachedCDeviceInfo : 
	public CListableObject<CDeviceCache::CachedCDeviceInfo>
{
	CDevice			*pDevice;
	CString			name;
	CUnicodeString	volId;
	CUnicodeString	curLink;
};


// Class CDeviceCache member functions

CDeviceCache::CDeviceCache()
{
	Status() = mCDIAllocator.Status();

	if (Status().IsntError())
		Status() = mCDILock.Status();
}

PGPBoolean 
CDeviceCache::DoesEntryExist(const char *name) const
{
	pgpAssertStrValid(name);
	PGPBoolean	exists	= FALSE;

	mCDILock.StartReading();
	exists = IsntNull(FindEntry(name));
	mCDILock.StopReading();

	return exists;
}

CComboError 
CDeviceCache::CreateEntry(const char *name)
{
	pgpAssertStrValid(name);
	CComboError	error;

	mCDILock.StartWriting();

	if (IsntNull(FindEntry(name)))
	{
		mCDILock.StopWriting();
		return error;
	}

	CachedCDeviceInfo	*pCDI;
	error = mCDIAllocator.Allocate(pCDI);

	if (error.IsntError())
	{
		pCDI->pDevice = NULL;
		error = pCDI->name.Status();

		if (error.IsntError())
			error = pCDI->curLink.Status();

		if (error.IsntError())
			error = pCDI->name.Assign(name);

		if (error.IsntError())
			mCDIList.AddHead(pCDI);

		if (error.IsError())
			mCDIAllocator.Free(pCDI);
	}

	mCDILock.StopWriting();

	return error;
}

void 
CDeviceCache::DeleteEntry(const char *name)
{
	pgpAssertStrValid(name);

	mCDILock.StartWriting();
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
	{
		mCDILock.StopWriting();
		return;
	}

	if (IsNull(pCDI))
		return;

	if (IsntNull(pCDI->pDevice))
		delete pCDI->pDevice;

	mCDIList.Remove(pCDI);
	mCDIAllocator.Free(pCDI);

	mCDILock.StopWriting();
}

CComboError 
CDeviceCache::SetEntryDevice(const char *name, CDevice *pDevice)
{
	pgpAssertStrValid(name);
	pgpAssertAddrValid(pDevice, CDevice);

	mCDILock.StartWriting();

	CComboError			error;
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
	{
		mCDILock.StopWriting();
		error.pgpErr = kPGPError_ItemNotFound;
	}

	if (error.IsntError())
	{
		if (IsntNull(pCDI->pDevice))
			delete pCDI->pDevice;

		pCDI->pDevice = pDevice;
	}

	mCDILock.StopWriting();

	return error;
}

CComboError 
CDeviceCache::GetEntryDevice(const char *name, CDevice *&pDevice) const
{
	pgpAssertStrValid(name);

	mCDILock.StartReading();

	CComboError			error;
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
		error.pgpErr = kPGPError_ItemNotFound;

	if (error.IsntError())
		pDevice = pCDI->pDevice;

	mCDILock.StopReading();

	return error;
}

CComboError 
CDeviceCache::SetEntryVolId(const char *name, const CUnicodeString& volId)
{
	pgpAssertStrValid(name);

	mCDILock.StartWriting();

	CComboError			error;
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
	{
		mCDILock.StopWriting();
		error.pgpErr = kPGPError_ItemNotFound;
	}

	if (error.IsntError())
		error = pCDI->volId.Assign(volId);

	mCDILock.StopWriting();

	return error;
}

CComboError 
CDeviceCache::GetEntryVolId(const char *name, CUnicodeString& volId) const
{
	pgpAssertStrValid(name);

	mCDILock.StartReading();

	CComboError			error;
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
		error.pgpErr = kPGPError_ItemNotFound;

	if (error.IsntError())
		error = volId.Assign(pCDI->volId);

	mCDILock.StopReading();

	return error;
}

CComboError 
CDeviceCache::SetEntryCurLink(const char *name, const UNICODE_STRING& curLink)
{
	pgpAssertStrValid(name);

	mCDILock.StartWriting();

	CComboError			error;
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
	{
		mCDILock.StopWriting();
		error.pgpErr = kPGPError_ItemNotFound;
	}

	if (error.IsntError())
		error = pCDI->curLink.Assign(curLink);

	mCDILock.StopWriting();

	return error;
}

CComboError 
CDeviceCache::GetEntryCurLink(const char *name, CUnicodeString& curLink) const
{
	pgpAssertStrValid(name);

	mCDILock.StartReading();

	CComboError			error;
	CachedCDeviceInfo	*pCDI	= FindEntry(name);

	if (IsNull(pCDI))
		error.pgpErr = kPGPError_ItemNotFound;

	if (error.IsntError())
		error = curLink.Assign(pCDI->curLink);

	mCDILock.StopReading();

	return error;
}

CDeviceCache::CachedCDeviceInfo * 
CDeviceCache::FindEntry(const char *name) const
{
	pgpAssertStrValid(name);

	CachedCDeviceInfo	*pCDI	= mCDIList.Head();

	while (IsntNull(pCDI))
	{
		if (pCDI->name.Compare(name))
			break;

		pCDI = mCDIList.Next(pCDI);
	}

	return pCDI;
}

void 
CDeviceCache::Shutdown()
{
	mCDILock.StartWriting();

	CachedCDeviceInfo	*pCDI	= mCDIList.Head();

	while (IsntNull(pCDI))
	{
		CachedCDeviceInfo	*pNext	= mCDIList.Next(pCDI);

		if (IsntNull(pCDI->pDevice))
			delete pCDI->pDevice;

		mCDIList.Remove(pCDI);
		mCDIAllocator.Free(pCDI);

		pCDI = pNext;
	}

	mCDILock.StopWriting();
}