1/*
2 * Copyright (C) 2009 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 *     * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 *     * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 *     * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31#ifndef WebStorageArea_h
32#define WebStorageArea_h
33
34#include "WebCommon.h"
35#include "WebString.h"
36
37namespace blink {
38
39class WebURL;
40
41class WebStorageArea {
42public:
43    virtual ~WebStorageArea() { }
44
45    enum Result {
46        ResultOK = 0,
47        ResultBlockedByQuota,
48        ResultLast = ResultBlockedByQuota
49    };
50
51    // The number of key/value pairs in the storage area.
52    virtual unsigned length() = 0;
53
54    // Get a value for a specific key. Valid key indices are 0 through length() - 1.
55    // Indexes may change on any set/removeItem call. Will return null if the index
56    // provided is out of range.
57    virtual WebString key(unsigned index) = 0;
58
59    // Get the value that corresponds to a specific key. This returns null if there is
60    // no entry for that key.
61    virtual WebString getItem(const WebString& key) = 0;
62
63    // Set the value that corresponds to a specific key. Result will either be ResultOK
64    // or some particular error. The value is NOT set when there's an error. |pageUrl| is the
65    // url that should be used if a storage event fires.
66    virtual void setItem(const WebString& key, const WebString& newValue, const WebURL& pageUrl, Result& result)
67    {
68        WebString unused;
69        setItem(key, newValue, pageUrl, result, unused);
70    }
71
72
73    // Remove the value associated with a particular key. |pageUrl| is the url that should be used
74    // if a storage event fires.
75    virtual void removeItem(const WebString& key, const WebURL& pageUrl)
76    {
77        WebString unused;
78        removeItem(key, pageUrl, unused);
79    }
80
81    // Clear all key/value pairs. |pageUrl| is the url that should be used if a storage event fires.
82    virtual void clear(const WebURL& pageUrl)
83    {
84        bool unused;
85        clear(pageUrl, unused);
86    }
87
88    // Returns amount of bytes occupied by the storage cache in physical memory.
89    virtual size_t memoryBytesUsedByCache() const { return 0; }
90
91    // DEPRECATED - being replaced by the async variants above which do not return oldValues or block until completion.
92    virtual void setItem(const WebString& key, const WebString& newValue, const WebURL&, Result&, WebString& oldValue) { }
93    virtual void removeItem(const WebString& key, const WebURL& pageUrl, WebString& oldValue)  { }
94    virtual void clear(const WebURL& pageUrl, bool& somethingCleared)  { }
95};
96
97} // namespace blink
98
99#endif // WebStorageArea_h
100