VBox/com/Guid.h

	Guid.h revision 677833bc953b6cb418c701facbdcf4aa18d6c44e
/** @file
 *
 * MS COM / XPCOM Abstraction Layer:
 * Guid class declaration
 */

/*
 * Copyright (C) 2006 InnoTek Systemberatung GmbH
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License as published by the Free Software Foundation,
 * in version 2 as it comes in the "COPYING" file of the VirtualBox OSE
 * distribution. VirtualBox OSE is distributed in the hope that it will
 * be useful, but WITHOUT ANY WARRANTY of any kind.
 *
 * If you received this file as part of a commercial VirtualBox
 * distribution, then only the terms of your commercial VirtualBox
 * license agreement apply instead of the previous paragraph.
 */

#ifndef __VBox_com_Guid_h__
#define __VBox_com_Guid_h__

#if !defined (__WIN__)
#include <nsMemory.h>
#endif

#include "VBox/com/string.h"

#include <iprt/uuid.h>

namespace com
{

/**
 *  Helper class that represents the UUID type and hides platform-siecific
 *  implementation details.
 */
class Guid
{
public:

    Guid () { ::RTUuidClear (&uuid); }
    Guid (const Guid &that) { uuid = that.uuid; }
    Guid (const RTUUID &that) { uuid = that; }
    Guid (const GUID &that) { ::memcpy (&uuid, &that, sizeof (GUID)); }
    Guid (const char *that) {
        ::RTUuidClear (&uuid);
        ::RTUuidFromStr (&uuid, that);
    }

    Guid &operator= (const Guid &that) {
        ::memcpy (&uuid, &that.uuid, sizeof (RTUUID));
        return *this;
    }
    Guid &operator= (const GUID &guid) {
        ::memcpy (&uuid, &guid, sizeof (GUID));
        return *this;
    }
    Guid &operator= (const RTUUID &guid) {
        ::memcpy (&uuid, &guid, sizeof (RTUUID));
        return *this;
    }
    Guid &operator= (const char *str) {
        ::RTUuidFromStr (&uuid, str);
        return *this;
    }

    void create() { ::RTUuidCreate (&uuid); }
    void clear() { ::RTUuidClear (&uuid); }

    Utf8Str toString () const {
        char buf [RTUUID_STR_LENGTH];
        ::RTUuidToStr (&uuid, buf, RTUUID_STR_LENGTH);
        return Utf8Str (buf);
    }

    bool isEmpty() const { return ::RTUuidIsNull (&uuid) != 0; }
    operator bool() const { return !isEmpty(); }

    bool operator== (const Guid &that) const { return ::RTUuidCompare (&uuid, &that.uuid) == 0; }
    bool operator== (const GUID &guid) const { return ::RTUuidCompare (&uuid, (PRTUUID) &guid) == 0; }
    bool operator!= (const Guid &that) const { return !operator==(that); }
    bool operator!= (const GUID &guid) const { return !operator==(guid); }
    bool operator< (const Guid &that) const { return ::RTUuidCompare (&uuid, &that.uuid) < 0; }
    bool operator< (const GUID &guid) const { return ::RTUuidCompare (&uuid, (PRTUUID) &guid) < 0; }

    // to pass instances as GUIDPARAM parameters to interface methods
    operator const GUID &() const { return *(GUID *) &uuid; }

    // to directly pass instances to CFGLDRQueryUUID()
    PRTUUID ptr() { return &uuid; }

    // to pass instances to printf-like functions
    PCRTUUID raw() const { return &uuid; }

    // to pass instances to RTUuid*() as a constant argument
    operator const RTUUID * const () const { return &uuid; }

#if defined(__WIN__)

    // to assign instances to GUIDPARAMOUT parameters from within the interface method
    const Guid &cloneTo (GUID *pguid) const {
        if (pguid) { ::memcpy (pguid, &uuid, sizeof (GUID)); }
        return *this;
    }

    // to pass instances as GUIDPARAMOUT parameters to interface methods
    GUID *asOutParam() { return (GUID *) &uuid; }

#else

    // to assign instances to GUIDPARAMOUT parameters from within the interface method
    const Guid &cloneTo (nsID **ppguid) const {
        if (ppguid) { *ppguid = (nsID *) nsMemory::Clone (&uuid, sizeof (nsID)); }
        return *this;
    }

    // internal helper class for asOutParam()
    class GuidOutParam {
        GuidOutParam (Guid &guid) : ptr (0), outer (guid) { outer.clear(); }
        nsID *ptr;
        Guid &outer;
        GuidOutParam (const GuidOutParam &that); // disabled
        GuidOutParam &operator= (const GuidOutParam &that); // disabled
    public:
        operator nsID **() { return &ptr; }
        ~GuidOutParam() {
            if (ptr && outer.isEmpty()) { outer = *ptr; nsMemory::Free (ptr); }
        }
        friend class Guid;
    };

    // to pass instances as GUIDPARAMOUT parameters to interface methods
    GuidOutParam asOutParam() { return GuidOutParam (*this); }

#endif

    // to directly test GUIDPARAM interface method's parameters
    static BOOL isEmpty (const GUID &guid) { return ::RTUuidIsNull ((PRTUUID) &guid); }

private:

    RTUUID uuid;
};

#if defined (_MSC_VER)

// work around error C2593 of the stupid MSVC 7.x ambiguity resolver
inline bool operator! (const Guid& guid) { return !bool (guid); }
inline bool operator&& (const Guid& guid, bool b) { return bool (guid) && b; }
inline bool operator|| (const Guid& guid, bool b) { return bool (guid) || b; }
inline bool operator&& (bool b, const Guid& guid) { return b && bool (guid); }
inline bool operator|| (bool b, const Guid& guid) { return b || bool (guid); }

#endif

}; // namespace com

#endif // __VBox_com_Guid_h__