1 /*
2  * Copyright (C) 2010 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 ShareableBitmap_h
27 #define ShareableBitmap_h
28 
29 #include "SharedMemory.h"
30 #include <WebCore/IntRect.h>
31 #include <wtf/PassOwnPtr.h>
32 #include <wtf/PassRefPtr.h>
33 #include <wtf/RefCounted.h>
34 #include <wtf/RefPtr.h>
35 
36 #if USE(CG)
37 #include <wtf/RetainPtr.h>
38 #endif
39 
40 namespace WebCore {
41     class GraphicsContext;
42 }
43 
44 namespace WebKit {
45 
46 class ShareableBitmap : public RefCounted<ShareableBitmap> {
47 public:
48     enum Flag {
49         SupportsAlpha = 1 << 0,
50     };
51     typedef unsigned Flags;
52 
53     class Handle {
54         WTF_MAKE_NONCOPYABLE(Handle);
55     public:
56         Handle();
57 
isNull()58         bool isNull() const { return m_handle.isNull(); }
59 
60         void encode(CoreIPC::ArgumentEncoder*) const;
61         static bool decode(CoreIPC::ArgumentDecoder*, Handle&);
62 
63     private:
64         friend class ShareableBitmap;
65 
66         mutable SharedMemory::Handle m_handle;
67         WebCore::IntSize m_size;
68         Flags m_flags;
69     };
70 
71     // Create a shareable bitmap that uses malloced memory.
72     static PassRefPtr<ShareableBitmap> create(const WebCore::IntSize&, Flags);
73 
74     // Create a shareable bitmap whose backing memory can be shared with another process.
75     static PassRefPtr<ShareableBitmap> createShareable(const WebCore::IntSize&, Flags);
76 
77     // Create a shareable bitmap from an already existing shared memory block.
78     static PassRefPtr<ShareableBitmap> create(const WebCore::IntSize&, Flags, PassRefPtr<SharedMemory>);
79 
80     // Create a shareable bitmap from a handle.
81     static PassRefPtr<ShareableBitmap> create(const Handle&);
82 
83     // Create a handle.
84     bool createHandle(Handle&);
85 
86     ~ShareableBitmap();
87 
size()88     const WebCore::IntSize& size() const { return m_size; }
bounds()89     WebCore::IntRect bounds() const { return WebCore::IntRect(WebCore::IntPoint(), size()); }
90 
91     bool resize(const WebCore::IntSize& size);
92 
93     // Create a graphics context that can be used to paint into the backing store.
94     PassOwnPtr<WebCore::GraphicsContext> createGraphicsContext();
95 
96     // Paint the backing store into the given context.
97     void paint(WebCore::GraphicsContext&, const WebCore::IntPoint& dstPoint, const WebCore::IntRect& srcRect);
98 
isBackedBySharedMemory()99     bool isBackedBySharedMemory() const { return m_sharedMemory; }
100 
101 #if USE(CG)
102     // This creates a copied CGImageRef (most likely a copy-on-write) of the shareable bitmap.
103     RetainPtr<CGImageRef> makeCGImageCopy();
104 
105     // This creates a CGImageRef that directly references the shared bitmap data.
106     // This is only safe to use when we know that the contents of the shareable bitmap won't change.
107     RetainPtr<CGImageRef> makeCGImage();
108 #endif
109 
110 private:
111     ShareableBitmap(const WebCore::IntSize&, Flags, void*);
112     ShareableBitmap(const WebCore::IntSize&, Flags, PassRefPtr<SharedMemory>);
113 
numBytesForSize(const WebCore::IntSize & size)114     static size_t numBytesForSize(const WebCore::IntSize& size) { return size.width() * size.height() * 4; }
115 
116 #if USE(CG)
117     RetainPtr<CGImageRef> createCGImage(CGDataProviderRef) const;
118     static void releaseBitmapContextData(void* typelessBitmap, void* typelessData);
119     static void releaseDataProviderData(void* typelessBitmap, const void* typelessData, size_t);
120 #endif
121 
122     void* data() const;
sizeInBytes()123     size_t sizeInBytes() const { return numBytesForSize(m_size); }
124 
125     WebCore::IntSize m_size;
126     Flags m_flags;
127 
128     // If the shareable bitmap is backed by shared memory, this points to the shared memory object.
129     RefPtr<SharedMemory> m_sharedMemory;
130 
131     // If the shareable bitmap is backed by fastMalloced memory, this points to the data.
132     void* m_data;
133 };
134 
135 } // namespace WebKit
136 
137 #endif // ShareableBitmap_h
138