netwerk/cache/nsDiskCache.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
   8 #ifndef _nsDiskCache_h_
   9 #define _nsDiskCache_h_
  10
  11 #include "nsCacheEntry.h"
  12
  13 #ifdef XP_WIN
  14 #include <winsock.h>  // for htonl/ntohl
  15 #endif
  16
  17
  18 class nsDiskCache {
  19 public:
  20     enum {
  21             kCurrentVersion = 0x00010013      // format = 16 bits major version/16 bits minor version
  22     };
  23
  24     enum { kData, kMetaData };
  25
  26     // Stores the reason why the cache is corrupt.
  27     // Note: I'm only listing the enum values explicitly for easy mapping when
  28     // looking at telemetry data.
  29     enum CorruptCacheInfo {
  30       kNotCorrupt = 0,
  31       kInvalidArgPointer = 1,
  32       kUnexpectedError = 2,
  33       kOpenCacheMapError = 3,
  34       kBlockFilesShouldNotExist = 4,
  35       kOutOfMemory = 5,
  36       kCreateCacheSubdirectories = 6,
  37       kBlockFilesShouldExist = 7,
  38       kHeaderSizeNotRead = 8,
  39       kHeaderIsDirty = 9,
  40       kVersionMismatch = 10,
  41       kRecordsIncomplete = 11,
  42       kHeaderIncomplete = 12,
  43       kNotEnoughToRead = 13,
  44       kEntryCountIncorrect = 14,
  45       kCouldNotGetBlockFileForIndex = 15,
  46       kCouldNotCreateBlockFile = 16,
  47       kBlockFileSizeError = 17,
  48       kBlockFileBitMapWriteError = 18,
  49       kBlockFileSizeLessThanBitMap = 19,
  50       kBlockFileBitMapReadError = 20,
  51       kBlockFileEstimatedSizeError = 21,
  52       kFlushHeaderError = 22
  53     };
  54
  55     // Parameter initval initializes internal state of hash function. Hash values are different
  56     // for the same text when different initval is used. It can be any random number.
  57     //
  58     // It can be used for generating 64-bit hash value:
  59     //   (PRUint64(Hash(key, initval1)) << 32) | Hash(key, initval2)
  60     //
  61     // It can be also used to hash multiple strings:
  62     //   h = Hash(string1, 0);
  63     //   h = Hash(string2, h);
  64     //   ...
  65     static PLDHashNumber    Hash(const char* key, PLDHashNumber initval=0);
  66     static nsresult         Truncate(PRFileDesc *  fd, PRUint32  newEOF);
  67 };
  68
  69 #endif // _nsDiskCache_h_