netwerk/cache/nsDiskCacheEntry.h

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
   2  *
   3  * This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef _nsDiskCacheEntry_h_
   8 #define _nsDiskCacheEntry_h_
   9
  10 #include "nsDiskCacheMap.h"
  11
  12 #include "nsCacheEntry.h"
  13
  14
  15 /******************************************************************************
  16  *  nsDiskCacheEntry
  17  *****************************************************************************/
  18 struct nsDiskCacheEntry {
  19     uint32_t        mHeaderVersion; // useful for stand-alone metadata files
  20     uint32_t        mMetaLocation;  // for verification
  21     int32_t         mFetchCount;
  22     uint32_t        mLastFetched;
  23     uint32_t        mLastModified;
  24     uint32_t        mExpirationTime;
  25     uint32_t        mDataSize;
  26     uint32_t        mKeySize;       // includes terminating null byte
  27     uint32_t        mMetaDataSize;  // includes terminating null byte
  28     // followed by key data (mKeySize bytes)
  29     // followed by meta data (mMetaDataSize bytes)
  30
  31     uint32_t        Size()    { return sizeof(nsDiskCacheEntry) +
  32                                     mKeySize + mMetaDataSize;
  33                               }
  34
  35     char*           Key()     { return reinterpret_cast<char*const>(this) +
  36                                     sizeof(nsDiskCacheEntry);
  37                               }
  38
  39     char*           MetaData()
  40                               { return Key() + mKeySize; }
  41
  42     nsCacheEntry *  CreateCacheEntry(nsCacheDevice *  device);
  43
  44     void Swap()         // host to network (memory to disk)
  45     {
  46 #if defined(IS_LITTLE_ENDIAN)
  47         mHeaderVersion      = htonl(mHeaderVersion);
  48         mMetaLocation       = htonl(mMetaLocation);
  49         mFetchCount         = htonl(mFetchCount);
  50         mLastFetched        = htonl(mLastFetched);
  51         mLastModified       = htonl(mLastModified);
  52         mExpirationTime     = htonl(mExpirationTime);
  53         mDataSize           = htonl(mDataSize);
  54         mKeySize            = htonl(mKeySize);
  55         mMetaDataSize       = htonl(mMetaDataSize);
  56 #endif
  57     }
  58
  59     void Unswap()       // network to host (disk to memory)
  60     {
  61 #if defined(IS_LITTLE_ENDIAN)
  62         mHeaderVersion      = ntohl(mHeaderVersion);
  63         mMetaLocation       = ntohl(mMetaLocation);
  64         mFetchCount         = ntohl(mFetchCount);
  65         mLastFetched        = ntohl(mLastFetched);
  66         mLastModified       = ntohl(mLastModified);
  67         mExpirationTime     = ntohl(mExpirationTime);
  68         mDataSize           = ntohl(mDataSize);
  69         mKeySize            = ntohl(mKeySize);
  70         mMetaDataSize       = ntohl(mMetaDataSize);
  71 #endif
  72     }
  73 };
  74
  75
  76 /******************************************************************************
  77  *  nsDiskCacheEntryInfo
  78  *****************************************************************************/
  79 class nsDiskCacheEntryInfo : public nsICacheEntryInfo {
  80 public:
  81     NS_DECL_ISUPPORTS
  82     NS_DECL_NSICACHEENTRYINFO
  83
  84     nsDiskCacheEntryInfo(const char * deviceID, nsDiskCacheEntry * diskEntry)
  85         : mDeviceID(deviceID)
  86         , mDiskEntry(diskEntry)
  87     {
  88     }
  89
  90     const char* Key() { return mDiskEntry->Key(); }
  91
  92 private:
  93     virtual ~nsDiskCacheEntryInfo() {}
  94
  95     const char *        mDeviceID;
  96     nsDiskCacheEntry *  mDiskEntry;
  97 };
  98
  99
 100 #endif /* _nsDiskCacheEntry_h_ */