pjs/netwerk/cache/nsMemoryCacheDevice.h

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/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is nsMemoryCacheDevice.h, released
* February 20, 2001.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 2001
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Gordon Sheridan, 20-February-2001
* Brian Ryner <bryner@brianryner.com>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. 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 MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef _nsMemoryCacheDevice_h_
#define _nsMemoryCacheDevice_h_
#include "nsCacheDevice.h"
#include "pldhash.h"
#include "nsCacheEntry.h"
class nsMemoryCacheDeviceInfo;
/******************************************************************************
* nsMemoryCacheDevice
******************************************************************************/
class nsMemoryCacheDevice : public nsCacheDevice
{
public:
nsMemoryCacheDevice();
virtual ~nsMemoryCacheDevice();
virtual nsresult Init();
virtual nsresult Shutdown();
virtual const char * GetDeviceID(void);
virtual nsresult BindEntry( nsCacheEntry * entry );
virtual nsCacheEntry * FindEntry( nsCString * key, PRBool *collision );
virtual void DoomEntry( nsCacheEntry * entry );
virtual nsresult DeactivateEntry( nsCacheEntry * entry );
virtual nsresult OpenInputStreamForEntry(nsCacheEntry * entry,
nsCacheAccessMode mode,
PRUint32 offset,
nsIInputStream ** result);
virtual nsresult OpenOutputStreamForEntry(nsCacheEntry * entry,
nsCacheAccessMode mode,
PRUint32 offset,
nsIOutputStream ** result);
virtual nsresult GetFileForEntry( nsCacheEntry * entry,
nsIFile ** result );
virtual nsresult OnDataSizeChange( nsCacheEntry * entry, PRInt32 deltaSize );
virtual nsresult Visit( nsICacheVisitor * visitor );
virtual nsresult EvictEntries(const char * clientID);
void SetCapacity(PRInt32 capacity);
bool EntryIsTooBig(PRInt64 entrySize);
private:
friend class nsMemoryCacheDeviceInfo;
enum { DELETE_ENTRY = PR_TRUE,
DO_NOT_DELETE_ENTRY = PR_FALSE };
void AdjustMemoryLimits( PRInt32 softLimit, PRInt32 hardLimit);
void EvictEntry( nsCacheEntry * entry , PRBool deleteEntry);
void EvictEntriesIfNecessary();
int EvictionList(nsCacheEntry * entry, PRInt32 deltaSize);
#ifdef DEBUG
void CheckEntryCount();
#endif
/*
* Data members
*/
enum {
kQueueCount = 24 // entries > 2^23 (8Mb) start in last queue
};
nsCacheEntryHashTable mMemCacheEntries;
PRBool mInitialized;
PRCList mEvictionList[kQueueCount];
PRInt32 mEvictionThreshold;
PRInt32 mHardLimit;
PRInt32 mSoftLimit;
PRInt32 mTotalSize;
PRInt32 mInactiveSize;
PRInt32 mEntryCount;
PRInt32 mMaxEntryCount;
// XXX what other stats do we want to keep?
};
/******************************************************************************
* nsMemoryCacheDeviceInfo - used to call nsIVisitor for about:cache
******************************************************************************/
class nsMemoryCacheDeviceInfo : public nsICacheDeviceInfo {
public:
NS_DECL_ISUPPORTS
NS_DECL_NSICACHEDEVICEINFO
nsMemoryCacheDeviceInfo(nsMemoryCacheDevice* device)
: mDevice(device)
{
}
virtual ~nsMemoryCacheDeviceInfo() {}
private:
nsMemoryCacheDevice* mDevice;
};
#endif // _nsMemoryCacheDevice_h_