| Index: net/disk_cache/disk_cache.h
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| diff --git a/net/disk_cache/disk_cache.h b/net/disk_cache/disk_cache.h
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| deleted file mode 100644
|
| index 769ab361b199695bc68827815fc3e481cf39666a..0000000000000000000000000000000000000000
|
| --- a/net/disk_cache/disk_cache.h
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| +++ /dev/null
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| @@ -1,327 +0,0 @@
|
| -// Copyright (c) 2012 The Chromium Authors. All rights reserved.
|
| -// Use of this source code is governed by a BSD-style license that can be
|
| -// found in the LICENSE file.
|
| -
|
| -// Defines the public interface of the disk cache. For more details see
|
| -// http://dev.chromium.org/developers/design-documents/network-stack/disk-cache
|
| -
|
| -#ifndef NET_DISK_CACHE_DISK_CACHE_H_
|
| -#define NET_DISK_CACHE_DISK_CACHE_H_
|
| -
|
| -#include <string>
|
| -#include <vector>
|
| -
|
| -#include "base/basictypes.h"
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| -#include "base/memory/ref_counted.h"
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| -#include "base/memory/scoped_ptr.h"
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| -#include "base/time/time.h"
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| -#include "net/base/cache_type.h"
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| -#include "net/base/completion_callback.h"
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| -#include "net/base/net_export.h"
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| -
|
| -namespace base {
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| -class FilePath;
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| -class SingleThreadTaskRunner;
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| -}
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| -
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| -namespace net {
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| -class IOBuffer;
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| -class NetLog;
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| -}
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| -
|
| -namespace disk_cache {
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| -
|
| -class Entry;
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| -class Backend;
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| -
|
| -// Returns an instance of a Backend of the given |type|. |path| points to a
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| -// folder where the cached data will be stored (if appropriate). This cache
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| -// instance must be the only object that will be reading or writing files to
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| -// that folder. The returned object should be deleted when not needed anymore.
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| -// If |force| is true, and there is a problem with the cache initialization, the
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| -// files will be deleted and a new set will be created. |max_bytes| is the
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| -// maximum size the cache can grow to. If zero is passed in as |max_bytes|, the
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| -// cache will determine the value to use. |thread| can be used to perform IO
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| -// operations if a dedicated thread is required; a valid value is expected for
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| -// any backend that performs operations on a disk. The returned pointer can be
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| -// NULL if a fatal error is found. The actual return value of the function is a
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| -// net error code. If this function returns ERR_IO_PENDING, the |callback| will
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| -// be invoked when a backend is available or a fatal error condition is reached.
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| -// The pointer to receive the |backend| must remain valid until the operation
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| -// completes (the callback is notified).
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| -NET_EXPORT int CreateCacheBackend(
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| - net::CacheType type,
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| - net::BackendType backend_type,
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| - const base::FilePath& path,
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| - int max_bytes,
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| - bool force,
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| - const scoped_refptr<base::SingleThreadTaskRunner>& thread,
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| - net::NetLog* net_log,
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| - scoped_ptr<Backend>* backend,
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| - const net::CompletionCallback& callback);
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| -
|
| -// The root interface for a disk cache instance.
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| -class NET_EXPORT Backend {
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| - public:
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| - typedef net::CompletionCallback CompletionCallback;
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| -
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| - class Iterator {
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| - public:
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| - virtual ~Iterator() {}
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| -
|
| - // OpenNextEntry returns |net::OK| and provides |next_entry| if there is an
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| - // entry to enumerate. It returns |net::ERR_FAILED| at the end of
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| - // enumeration. If the function returns |net::ERR_IO_PENDING|, then the
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| - // final result will be passed to the provided |callback|, otherwise
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| - // |callback| will not be called. If any entry in the cache is modified
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| - // during iteration, the result of this function is thereafter undefined.
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| - //
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| - // Calling OpenNextEntry after the backend which created it is destroyed
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| - // may fail with |net::ERR_FAILED|; however it should not crash.
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| - //
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| - // Some cache backends make stronger guarantees about mutation during
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| - // iteration, see top comment in simple_backend_impl.h for details.
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| - virtual int OpenNextEntry(Entry** next_entry,
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| - const CompletionCallback& callback) = 0;
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| - };
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| -
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| - // If the backend is destroyed when there are operations in progress (any
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| - // callback that has not been invoked yet), this method cancels said
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| - // operations so the callbacks are not invoked, possibly leaving the work
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| - // half way (for instance, dooming just a few entries). Note that pending IO
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| - // for a given Entry (as opposed to the Backend) will still generate a
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| - // callback from within this method.
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| - virtual ~Backend() {}
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| -
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| - // Returns the type of this cache.
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| - virtual net::CacheType GetCacheType() const = 0;
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| -
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| - // Returns the number of entries in the cache.
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| - virtual int32 GetEntryCount() const = 0;
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| -
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| - // Opens an existing entry. Upon success, |entry| holds a pointer to an Entry
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| - // object representing the specified disk cache entry. When the entry pointer
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| - // is no longer needed, its Close method should be called. The return value is
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| - // a net error code. If this method returns ERR_IO_PENDING, the |callback|
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| - // will be invoked when the entry is available. The pointer to receive the
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| - // |entry| must remain valid until the operation completes.
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| - virtual int OpenEntry(const std::string& key, Entry** entry,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Creates a new entry. Upon success, the out param holds a pointer to an
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| - // Entry object representing the newly created disk cache entry. When the
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| - // entry pointer is no longer needed, its Close method should be called. The
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| - // return value is a net error code. If this method returns ERR_IO_PENDING,
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| - // the |callback| will be invoked when the entry is available. The pointer to
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| - // receive the |entry| must remain valid until the operation completes.
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| - virtual int CreateEntry(const std::string& key, Entry** entry,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Marks the entry, specified by the given key, for deletion. The return value
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| - // is a net error code. If this method returns ERR_IO_PENDING, the |callback|
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| - // will be invoked after the entry is doomed.
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| - virtual int DoomEntry(const std::string& key,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Marks all entries for deletion. The return value is a net error code. If
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| - // this method returns ERR_IO_PENDING, the |callback| will be invoked when the
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| - // operation completes.
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| - virtual int DoomAllEntries(const CompletionCallback& callback) = 0;
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| -
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| - // Marks a range of entries for deletion. This supports unbounded deletes in
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| - // either direction by using null Time values for either argument. The return
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| - // value is a net error code. If this method returns ERR_IO_PENDING, the
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| - // |callback| will be invoked when the operation completes.
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| - // Entries with |initial_time| <= access time < |end_time| are deleted.
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| - virtual int DoomEntriesBetween(base::Time initial_time,
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| - base::Time end_time,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Marks all entries accessed since |initial_time| for deletion. The return
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| - // value is a net error code. If this method returns ERR_IO_PENDING, the
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| - // |callback| will be invoked when the operation completes.
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| - // Entries with |initial_time| <= access time are deleted.
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| - virtual int DoomEntriesSince(base::Time initial_time,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Returns an iterator which will enumerate all entries of the cache in an
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| - // undefined order.
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| - virtual scoped_ptr<Iterator> CreateIterator() = 0;
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| -
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| - // Return a list of cache statistics.
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| - virtual void GetStats(
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| - std::vector<std::pair<std::string, std::string> >* stats) = 0;
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| -
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| - // Called whenever an external cache in the system reuses the resource
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| - // referred to by |key|.
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| - virtual void OnExternalCacheHit(const std::string& key) = 0;
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| -};
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| -
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| -// This interface represents an entry in the disk cache.
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| -class NET_EXPORT Entry {
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| - public:
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| - typedef net::CompletionCallback CompletionCallback;
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| - typedef net::IOBuffer IOBuffer;
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| -
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| - // Marks this cache entry for deletion.
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| - virtual void Doom() = 0;
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| -
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| - // Releases this entry. Calling this method does not cancel pending IO
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| - // operations on this entry. Even after the last reference to this object has
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| - // been released, pending completion callbacks may be invoked.
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| - virtual void Close() = 0;
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| -
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| - // Returns the key associated with this cache entry.
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| - virtual std::string GetKey() const = 0;
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| -
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| - // Returns the time when this cache entry was last used.
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| - virtual base::Time GetLastUsed() const = 0;
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| -
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| - // Returns the time when this cache entry was last modified.
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| - virtual base::Time GetLastModified() const = 0;
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| -
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| - // Returns the size of the cache data with the given index.
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| - virtual int32 GetDataSize(int index) const = 0;
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| -
|
| - // Copies cached data into the given buffer of length |buf_len|. Returns the
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| - // number of bytes read or a network error code. If this function returns
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| - // ERR_IO_PENDING, the completion callback will be called on the current
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| - // thread when the operation completes, and a reference to |buf| will be
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| - // retained until the callback is called. Note that as long as the function
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| - // does not complete immediately, the callback will always be invoked, even
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| - // after Close has been called; in other words, the caller may close this
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| - // entry without having to wait for all the callbacks, and still rely on the
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| - // cleanup performed from the callback code.
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| - virtual int ReadData(int index, int offset, IOBuffer* buf, int buf_len,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Copies data from the given buffer of length |buf_len| into the cache.
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| - // Returns the number of bytes written or a network error code. If this
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| - // function returns ERR_IO_PENDING, the completion callback will be called
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| - // on the current thread when the operation completes, and a reference to
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| - // |buf| will be retained until the callback is called. Note that as long as
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| - // the function does not complete immediately, the callback will always be
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| - // invoked, even after Close has been called; in other words, the caller may
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| - // close this entry without having to wait for all the callbacks, and still
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| - // rely on the cleanup performed from the callback code.
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| - // If truncate is true, this call will truncate the stored data at the end of
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| - // what we are writing here.
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| - virtual int WriteData(int index, int offset, IOBuffer* buf, int buf_len,
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| - const CompletionCallback& callback,
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| - bool truncate) = 0;
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| -
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| - // Sparse entries support:
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| - //
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| - // A Backend implementation can support sparse entries, so the cache keeps
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| - // track of which parts of the entry have been written before. The backend
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| - // will never return data that was not written previously, so reading from
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| - // such region will return 0 bytes read (or actually the number of bytes read
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| - // before reaching that region).
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| - //
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| - // There are only two streams for sparse entries: a regular control stream
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| - // (index 0) that must be accessed through the regular API (ReadData and
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| - // WriteData), and one sparse stream that must me accessed through the sparse-
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| - // aware API that follows. Calling a non-sparse aware method with an index
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| - // argument other than 0 is a mistake that results in implementation specific
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| - // behavior. Using a sparse-aware method with an entry that was not stored
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| - // using the same API, or with a backend that doesn't support sparse entries
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| - // will return ERR_CACHE_OPERATION_NOT_SUPPORTED.
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| - //
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| - // The storage granularity of the implementation should be at least 1 KB. In
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| - // other words, storing less than 1 KB may result in an implementation
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| - // dropping the data completely, and writing at offsets not aligned with 1 KB,
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| - // or with lengths not a multiple of 1 KB may result in the first or last part
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| - // of the data being discarded. However, two consecutive writes should not
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| - // result in a hole in between the two parts as long as they are sequential
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| - // (the second one starts where the first one ended), and there is no other
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| - // write between them.
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| - //
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| - // The Backend implementation is free to evict any range from the cache at any
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| - // moment, so in practice, the previously stated granularity of 1 KB is not
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| - // as bad as it sounds.
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| - //
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| - // The sparse methods don't support multiple simultaneous IO operations to the
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| - // same physical entry, so in practice a single object should be instantiated
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| - // for a given key at any given time. Once an operation has been issued, the
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| - // caller should wait until it completes before starting another one. This
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| - // requirement includes the case when an entry is closed while some operation
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| - // is in progress and another object is instantiated; any IO operation will
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| - // fail while the previous operation is still in-flight. In order to deal with
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| - // this requirement, the caller could either wait until the operation
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| - // completes before closing the entry, or call CancelSparseIO() before closing
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| - // the entry, and call ReadyForSparseIO() on the new entry and wait for the
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| - // callback before issuing new operations.
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| -
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| - // Behaves like ReadData() except that this method is used to access sparse
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| - // entries.
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| - virtual int ReadSparseData(int64 offset, IOBuffer* buf, int buf_len,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Behaves like WriteData() except that this method is used to access sparse
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| - // entries. |truncate| is not part of this interface because a sparse entry
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| - // is not expected to be reused with new data. To delete the old data and
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| - // start again, or to reduce the total size of the stream data (which implies
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| - // that the content has changed), the whole entry should be doomed and
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| - // re-created.
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| - virtual int WriteSparseData(int64 offset, IOBuffer* buf, int buf_len,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Returns information about the currently stored portion of a sparse entry.
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| - // |offset| and |len| describe a particular range that should be scanned to
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| - // find out if it is stored or not. |start| will contain the offset of the
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| - // first byte that is stored within this range, and the return value is the
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| - // minimum number of consecutive stored bytes. Note that it is possible that
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| - // this entry has stored more than the returned value. This method returns a
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| - // net error code whenever the request cannot be completed successfully. If
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| - // this method returns ERR_IO_PENDING, the |callback| will be invoked when the
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| - // operation completes, and |start| must remain valid until that point.
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| - virtual int GetAvailableRange(int64 offset, int len, int64* start,
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| - const CompletionCallback& callback) = 0;
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| -
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| - // Returns true if this entry could be a sparse entry or false otherwise. This
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| - // is a quick test that may return true even if the entry is not really
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| - // sparse. This method doesn't modify the state of this entry (it will not
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| - // create sparse tracking data). GetAvailableRange or ReadSparseData can be
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| - // used to perform a definitive test of whether an existing entry is sparse or
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| - // not, but that method may modify the current state of the entry (making it
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| - // sparse, for instance). The purpose of this method is to test an existing
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| - // entry, but without generating actual IO to perform a thorough check.
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| - virtual bool CouldBeSparse() const = 0;
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| -
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| - // Cancels any pending sparse IO operation (if any). The completion callback
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| - // of the operation in question will still be called when the operation
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| - // finishes, but the operation will finish sooner when this method is used.
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| - virtual void CancelSparseIO() = 0;
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| -
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| - // Returns OK if this entry can be used immediately. If that is not the
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| - // case, returns ERR_IO_PENDING and invokes the provided callback when this
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| - // entry is ready to use. This method always returns OK for non-sparse
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| - // entries, and returns ERR_IO_PENDING when a previous operation was cancelled
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| - // (by calling CancelSparseIO), but the cache is still busy with it. If there
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| - // is a pending operation that has not been cancelled, this method will return
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| - // OK although another IO operation cannot be issued at this time; in this
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| - // case the caller should just wait for the regular callback to be invoked
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| - // instead of using this method to provide another callback.
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| - //
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| - // Note that CancelSparseIO may have been called on another instance of this
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| - // object that refers to the same physical disk entry.
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| - // Note: This method is deprecated.
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| - virtual int ReadyForSparseIO(const CompletionCallback& callback) = 0;
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| -
|
| - protected:
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| - virtual ~Entry() {}
|
| -};
|
| -
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| -struct EntryDeleter {
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| - void operator()(Entry* entry) {
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| - // Note that |entry| is ref-counted.
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| - entry->Close();
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| - }
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| -};
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| -
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| -// Automatically closes an entry when it goes out of scope.
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| -typedef scoped_ptr<Entry, EntryDeleter> ScopedEntryPtr;
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| -
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| -} // namespace disk_cache
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| -
|
| -#endif // NET_DISK_CACHE_DISK_CACHE_H_
|
|
|