1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/netwerk/cache/nsDiskCacheBinding.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,120 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
1.5 + *
1.6 + * This Source Code Form is subject to the terms of the Mozilla Public
1.7 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.8 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.9 +
1.10 +
1.11 +#ifndef _nsDiskCacheBinding_h_
1.12 +#define _nsDiskCacheBinding_h_
1.13 +
1.14 +#include "mozilla/MemoryReporting.h"
1.15 +#include "nspr.h"
1.16 +#include "pldhash.h"
1.17 +
1.18 +#include "nsISupports.h"
1.19 +#include "nsCacheEntry.h"
1.20 +
1.21 +#include "nsDiskCacheMap.h"
1.22 +#include "nsDiskCacheStreams.h"
1.23 +
1.24 +
1.25 +/******************************************************************************
1.26 + * nsDiskCacheBinding
1.27 + *
1.28 + * Created for disk cache specific data and stored in nsCacheEntry.mData as
1.29 + * an nsISupports. Also stored in nsDiskCacheHashTable, with collisions
1.30 + * linked by the PRCList.
1.31 + *
1.32 + *****************************************************************************/
1.33 +
1.34 +class nsDiskCacheDeviceDeactivateEntryEvent;
1.35 +
1.36 +class nsDiskCacheBinding : public nsISupports, public PRCList {
1.37 +public:
1.38 + NS_DECL_THREADSAFE_ISUPPORTS
1.39 +
1.40 + nsDiskCacheBinding(nsCacheEntry* entry, nsDiskCacheRecord * record);
1.41 + virtual ~nsDiskCacheBinding();
1.42 +
1.43 + nsresult EnsureStreamIO();
1.44 + bool IsActive() { return mCacheEntry != nullptr;}
1.45 +
1.46 +// XXX make friends
1.47 +public:
1.48 + nsCacheEntry* mCacheEntry; // back pointer to parent nsCacheEntry
1.49 + nsDiskCacheRecord mRecord;
1.50 + nsDiskCacheStreamIO* mStreamIO; // strong reference
1.51 + bool mDoomed; // record is not stored in cache map
1.52 + uint8_t mGeneration; // possibly just reservation
1.53 +
1.54 + // If set, points to a pending event which will deactivate |mCacheEntry|.
1.55 + // If not set then either |mCacheEntry| is not deactivated, or it has been
1.56 + // deactivated but the device returned it from FindEntry() before the event
1.57 + // fired. In both two latter cases this binding is to be considered valid.
1.58 + nsDiskCacheDeviceDeactivateEntryEvent *mDeactivateEvent;
1.59 +};
1.60 +
1.61 +
1.62 +/******************************************************************************
1.63 + * Utility Functions
1.64 + *****************************************************************************/
1.65 +
1.66 +nsDiskCacheBinding * GetCacheEntryBinding(nsCacheEntry * entry);
1.67 +
1.68 +
1.69 +
1.70 +/******************************************************************************
1.71 + * nsDiskCacheBindery
1.72 + *
1.73 + * Used to keep track of nsDiskCacheBinding associated with active/bound (and
1.74 + * possibly doomed) entries. Lookups on 4 byte disk hash to find collisions
1.75 + * (which need to be doomed, instead of just evicted. Collisions are linked
1.76 + * using a PRCList to keep track of current generation number.
1.77 + *
1.78 + * Used to detect hash number collisions, and find available generation numbers.
1.79 + *
1.80 + * Not all nsDiskCacheBinding have a generation number.
1.81 + *
1.82 + * Generation numbers may be aquired late, or lost (when data fits in block file)
1.83 + *
1.84 + * Collisions can occur:
1.85 + * BindEntry() - hashnumbers collide (possibly different keys)
1.86 + *
1.87 + * Generation number required:
1.88 + * DeactivateEntry() - metadata written to disk, may require file
1.89 + * GetFileForEntry() - force data to require file
1.90 + * writing to stream - data size may require file
1.91 + *
1.92 + * Binding can be kept in PRCList in order of generation numbers.
1.93 + * Binding with no generation number can be Appended to PRCList (last).
1.94 + *
1.95 + *****************************************************************************/
1.96 +
1.97 +class nsDiskCacheBindery {
1.98 +public:
1.99 + nsDiskCacheBindery();
1.100 + ~nsDiskCacheBindery();
1.101 +
1.102 + nsresult Init();
1.103 + void Reset();
1.104 +
1.105 + nsDiskCacheBinding * CreateBinding(nsCacheEntry * entry,
1.106 + nsDiskCacheRecord * record);
1.107 +
1.108 + nsDiskCacheBinding * FindActiveBinding(uint32_t hashNumber);
1.109 + void RemoveBinding(nsDiskCacheBinding * binding);
1.110 + bool ActiveBindings();
1.111 +
1.112 + size_t SizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf);
1.113 +
1.114 +private:
1.115 + nsresult AddBinding(nsDiskCacheBinding * binding);
1.116 +
1.117 + // member variables
1.118 + static const PLDHashTableOps ops;
1.119 + PLDHashTable table;
1.120 + bool initialized;
1.121 +};
1.122 +
1.123 +#endif /* _nsDiskCacheBinding_h_ */
