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 SharedMemory_h 27#define SharedMemory_h 28 29#include <wtf/Noncopyable.h> 30#include <wtf/PassRefPtr.h> 31#include <wtf/RefCounted.h> 32 33#if PLATFORM(QT) || PLATFORM(GTK) || PLATFORM(EFL) 34#include "Attachment.h" 35#include <wtf/text/WTFString.h> 36#endif 37 38namespace CoreIPC { 39 class ArgumentDecoder; 40 class ArgumentEncoder; 41} 42 43namespace WebKit { 44 45class SharedMemory : public RefCounted<SharedMemory> { 46public: 47 enum Protection { 48 ReadOnly, 49 ReadWrite 50 }; 51 52 class Handle { 53 WTF_MAKE_NONCOPYABLE(Handle); 54 public: 55 Handle(); 56 ~Handle(); 57 58 bool isNull() const; 59 60 void encode(CoreIPC::ArgumentEncoder&) const; 61 static bool decode(CoreIPC::ArgumentDecoder&, Handle&); 62 63#if USE(UNIX_DOMAIN_SOCKETS) 64 CoreIPC::Attachment releaseToAttachment() const; 65 void adoptFromAttachment(int fileDescriptor, size_t); 66#endif 67 private: 68 friend class SharedMemory; 69#if OS(DARWIN) 70 mutable mach_port_t m_port; 71#elif OS(WINDOWS) 72 mutable HANDLE m_handle; 73#elif USE(UNIX_DOMAIN_SOCKETS) 74 mutable int m_fileDescriptor; 75#endif 76 size_t m_size; 77 }; 78 79 // Create a shared memory object with the given size. Will return 0 on failure. 80 static PassRefPtr<SharedMemory> create(size_t); 81 82 // Create a shared memory object from the given handle and the requested protection. Will return 0 on failure. 83 static PassRefPtr<SharedMemory> create(const Handle&, Protection); 84 85 // Create a shared memory object with the given size by vm_copy'ing the given buffer. 86 // Will return 0 on failure. 87 static PassRefPtr<SharedMemory> createFromVMBuffer(void*, size_t); 88 89#if OS(WINDOWS) 90 static PassRefPtr<SharedMemory> adopt(HANDLE, size_t, Protection); 91#endif 92 93 ~SharedMemory(); 94 95 bool createHandle(Handle&, Protection); 96 97 size_t size() const { return m_size; } 98 void* data() const { return m_data; } 99#if OS(WINDOWS) 100 HANDLE handle() const { return m_handle; } 101#endif 102 103 // Creates a copy-on-write copy of the first |size| bytes. 104 PassRefPtr<SharedMemory> createCopyOnWriteCopy(size_t) const; 105 106 // Return the system page size in bytes. 107 static unsigned systemPageSize(); 108 109private: 110 size_t m_size; 111 void* m_data; 112 bool m_shouldVMDeallocateData; 113 114#if OS(DARWIN) 115 mach_port_t m_port; 116#elif OS(WINDOWS) 117 HANDLE m_handle; 118#elif USE(UNIX_DOMAIN_SOCKETS) 119 int m_fileDescriptor; 120#endif 121}; 122 123}; 124 125#endif // SharedMemory_h 126