netwerk/cache/src/nsDiskCacheDevice.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
   2  *
   3  * ***** BEGIN LICENSE BLOCK *****
   4  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   5  *
   6  * The contents of this file are subject to the Mozilla Public License Version
   7  * 1.1 (the "License"); you may not use this file except in compliance with
   8  * the License. You may obtain a copy of the License at
   9  * http://www.mozilla.org/MPL/
  10  *
  11  * Software distributed under the License is distributed on an "AS IS" basis,
  12  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  13  * for the specific language governing rights and limitations under the
  14  * License.
  15  *
  16  * The Original Code is nsDiskCacheDevice.h, released
  17  * February 20, 2001.
  18  *
  19  * The Initial Developer of the Original Code is
  20  * Netscape Communications Corporation.
  21  * Portions created by the Initial Developer are Copyright (C) 2001
  22  * the Initial Developer. All Rights Reserved.
  23  *
  24  * Contributor(s):
  25  *   Gordon Sheridan <gordon@netscape.com>
  26  *   Patrick C. Beard <beard@netscape.com>
  27  *
  28  * Alternatively, the contents of this file may be used under the terms of
  29  * either the GNU General Public License Version 2 or later (the "GPL"), or
  30  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  31  * in which case the provisions of the GPL or the LGPL are applicable instead
  32  * of those above. If you wish to allow use of your version of this file only
  33  * under the terms of either the GPL or the LGPL, and not to allow others to
  34  * use your version of this file under the terms of the MPL, indicate your
  35  * decision by deleting the provisions above and replace them with the notice
  36  * and other provisions required by the GPL or the LGPL. If you do not delete
  37  * the provisions above, a recipient may use your version of this file under
  38  * the terms of any one of the MPL, the GPL or the LGPL.
  39  *
  40  * ***** END LICENSE BLOCK ***** */
  41
  42 #ifndef _nsDiskCacheDevice_h_
  43 #define _nsDiskCacheDevice_h_
  44
  45 #include "nsCacheDevice.h"
  46 #include "nsDiskCacheBinding.h"
  47 #include "nsDiskCacheBlockFile.h"
  48 #include "nsDiskCacheEntry.h"
  49
  50 #include "nsILocalFile.h"
  51 #include "nsIObserver.h"
  52 #include "nsCOMArray.h"
  53
  54 class nsDiskCacheMap;
  55
  56
  57 class nsDiskCacheDevice : public nsCacheDevice {
  58 public:
  59     nsDiskCacheDevice();
  60     virtual ~nsDiskCacheDevice();
  61
  62     virtual nsresult        Init();
  63     virtual nsresult        Shutdown();
  64
  65     virtual const char *    GetDeviceID(void);
  66     virtual nsCacheEntry *  FindEntry(nsCString * key, PRBool *collision);
  67     virtual nsresult        DeactivateEntry(nsCacheEntry * entry);
  68     virtual nsresult        BindEntry(nsCacheEntry * entry);
  69     virtual void            DoomEntry( nsCacheEntry * entry );
  70
  71     virtual nsresult OpenInputStreamForEntry(nsCacheEntry *    entry,
  72                                              nsCacheAccessMode mode,
  73                                              PRUint32          offset,
  74                                              nsIInputStream ** result);
  75
  76     virtual nsresult OpenOutputStreamForEntry(nsCacheEntry *     entry,
  77                                               nsCacheAccessMode  mode,
  78                                               PRUint32           offset,
  79                                               nsIOutputStream ** result);
  80
  81     virtual nsresult        GetFileForEntry(nsCacheEntry *    entry,
  82                                             nsIFile **        result);
  83
  84     virtual nsresult        OnDataSizeChange(nsCacheEntry * entry, PRInt32 deltaSize);
  85
  86     virtual nsresult        Visit(nsICacheVisitor * visitor);
  87
  88     virtual nsresult        EvictEntries(const char * clientID);
  89
  90     /**
  91      * Preference accessors
  92      */
  93     void                    SetCacheParentDirectory(nsILocalFile * parentDir);
  94     void                    SetCapacity(PRUint32  capacity);
  95
  96 /* private: */
  97
  98     void                    getCacheDirectory(nsILocalFile ** result);
  99     PRUint32                getCacheCapacity();
 100     PRUint32                getCacheSize();
 101     PRUint32                getEntryCount();
 102
 103     nsDiskCacheMap *        CacheMap()    { return &mCacheMap; }
 104
 105 private:
 106     /**
 107      *  Private methods
 108      */
 109
 110     PRBool                  Initialized() { return mInitialized; }
 111
 112     nsresult                Shutdown_Private(PRBool flush);
 113
 114     nsresult                OpenDiskCache();
 115     nsresult                ClearDiskCache();
 116
 117     nsresult                EvictDiskCacheEntries(PRUint32  targetCapacity);
 118
 119     /**
 120      *  Member variables
 121      */
 122     nsCOMPtr<nsILocalFile>  mCacheDirectory;
 123     nsDiskCacheBindery      mBindery;
 124     PRUint32                mCacheCapacity;     // Unit is KiB's
 125     // XXX need soft/hard limits, currentTotal
 126     nsDiskCacheMap          mCacheMap;
 127     PRPackedBool            mInitialized;
 128 };
 129
 130 #endif // _nsDiskCacheDevice_h_