Source/WebKit2/Platform/CoreIPC/Attachment.h

/*
 * Copyright (C) 2010 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef Attachment_h
#define Attachment_h

namespace CoreIPC {

class ArgumentDecoder;
class ArgumentEncoder;

class Attachment {
public:
    Attachment();

    enum Type {
        Uninitialized,
#if PLATFORM(MAC)
        MachPortType,
        MachOOLMemoryType,
#elif USE(UNIX_DOMAIN_SOCKETS)
        MappedMemory
#endif
    };

#if PLATFORM(MAC)
    Attachment(mach_port_name_t port, mach_msg_type_name_t disposition);
    Attachment(void* address, mach_msg_size_t size, mach_msg_copy_options_t copyOptions, bool deallocate);
#elif USE(UNIX_DOMAIN_SOCKETS)
    Attachment(int fileDescriptor, size_t);
#endif

    Type type() const { return m_type; }

#if PLATFORM(MAC)
    void release();

    // MachPortType
    mach_port_name_t port() const { ASSERT(m_type == MachPortType); return m_port.port; }
    mach_msg_type_name_t disposition() const { ASSERT(m_type == MachPortType); return m_port.disposition; }

    // MachOOLMemoryType
    void* address() const { ASSERT(m_type == MachOOLMemoryType); return m_oolMemory.address; }
    mach_msg_size_t size() const { ASSERT(m_type == MachOOLMemoryType); return m_oolMemory.size; }
    mach_msg_copy_options_t copyOptions() const { ASSERT(m_type == MachOOLMemoryType); return m_oolMemory.copyOptions; }
    bool deallocate() const { ASSERT(m_type == MachOOLMemoryType); return m_oolMemory.deallocate; }
#elif USE(UNIX_DOMAIN_SOCKETS)
    size_t size() const { return m_size; }

    int releaseFileDescriptor() { int temp = m_fileDescriptor; m_fileDescriptor = -1; return temp; }
    int fileDescriptor() const { return m_fileDescriptor; }

    void dispose();
#endif

    void encode(ArgumentEncoder*) const;
    static bool decode(ArgumentDecoder*, Attachment&);
    
private:
    Type m_type;

#if PLATFORM(MAC)
    union {
        struct {
            mach_port_name_t port;
            mach_msg_type_name_t disposition;
        } m_port;
        struct {
            void* address;
            mach_msg_size_t size;
            mach_msg_copy_options_t copyOptions;
            bool deallocate;
        } m_oolMemory;
    };
#elif USE(UNIX_DOMAIN_SOCKETS)
    int m_fileDescriptor;
    size_t m_size;
#endif
};

} // namespace CoreIPC

#endif // Attachment_h