1/*
2 * Copyright (C) 2012 Apple 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
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
12 *
13 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
14 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23 * THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef ShareableResource_h
27#define ShareableResource_h
28
29#if ENABLE(SHAREABLE_RESOURCE)
30
31#include "SharedMemory.h"
32#include <wtf/RefCounted.h>
33#include <wtf/RefPtr.h>
34
35namespace WebCore {
36class SharedBuffer;
37}
38
39namespace WebKit {
40
41class ShareableResource : public RefCounted<ShareableResource> {
42public:
43
44 class Handle {
45 WTF_MAKE_NONCOPYABLE(Handle);
46 public:
47 Handle();
48 Handle(Handle&&) = default;
49 Handle& operator=(Handle&&) = default;
50
51 bool isNull() const { return m_handle.isNull(); }
52 unsigned size() const { return m_size; }
53
54 void encode(IPC::Encoder&) const;
55 static bool decode(IPC::Decoder&, Handle&);
56
57 RefPtr<WebCore::SharedBuffer> tryWrapInSharedBuffer() const;
58
59 private:
60 friend class ShareableResource;
61
62 mutable SharedMemory::Handle m_handle;
63 unsigned m_offset;
64 unsigned m_size;
65 };
66
67 // Create a shareable resource that uses malloced memory.
68 static Ref<ShareableResource> create(Ref<SharedMemory>&&, unsigned offset, unsigned size);
69
70 // Create a shareable resource from a handle.
71 static RefPtr<ShareableResource> map(const Handle&);
72
73 // Create a handle.
74 bool createHandle(Handle&);
75
76 ~ShareableResource();
77
78 const char* data() const;
79 unsigned size() const;
80
81private:
82 ShareableResource(Ref<SharedMemory>&&, unsigned offset, unsigned size);
83 RefPtr<WebCore::SharedBuffer> wrapInSharedBuffer();
84
85 Ref<SharedMemory> m_sharedMemory;
86
87 unsigned m_offset;
88 unsigned m_size;
89};
90
91} // namespace WebKit
92
93#endif // ENABLE(SHAREABLE_RESOURCE)
94
95#endif // ShareableResource_h
96