freebsd-nq/lib/libdevdctl/guid.h
Alan Somers 33d9904abc Partially revert r325011: restore Guid's default constructor
Reported by:	ohartmann
MFC after:	3 weeks
X-MFC-With:	325011
Sponsored by:	Spectra Logic Corp
2017-10-26 17:56:34 +00:00

155 lines
4.0 KiB
C++

/*-
* Copyright (c) 2012, 2013 Spectra Logic Corporation
* 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,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR 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 DAMAGES.
*
* Authors: Alan Somers (Spectra Logic Corporation)
*
* $FreeBSD$
*/
/**
* \file devdctl_guid.h
*
* Definition of the Guid class.
*/
#ifndef _DEVDCTL_GUID_H_
#define _DEVDCTL_GUID_H_
/*============================ Namespace Control =============================*/
namespace DevdCtl
{
/*============================= Class Definitions ============================*/
/*----------------------------------- Guid -----------------------------------*/
/**
* \brief Object that represents guids.
*
* It can generally be manipulated as a uint64_t, but with a special
* value INVALID_GUID that does not equal any valid guid.
*
* As of this writing, this class is only used to represent ZFS
* guids in events and spa_generate_guid() in spa_misc.c explicitly
* refuses to return a guid of 0. So this class uses 0 as the value
* for INVALID_GUID. In the future, if 0 is allowed to be a valid
* guid, the implementation of this class must change.
*/
class Guid
{
public:
/* Constructors */
/* Default constructor: an Invalid guid */
Guid();
/* Construct a guid from a provided integer */
Guid(uint64_t guid);
/* Construct a guid from a string in base 8, 10, or 16 */
Guid(const std::string &guid);
static Guid InvalidGuid();
/* Assignment */
Guid& operator=(const Guid& rhs);
/* Test the validity of this guid. */
bool IsValid() const;
/* Comparison to other Guid operators */
bool operator==(const Guid& rhs) const;
bool operator!=(const Guid& rhs) const;
/* Integer conversion operators */
operator uint64_t() const;
operator bool() const;
protected:
static const uint64_t INVALID_GUID = 0;
/* The integer value of the GUID. */
uint64_t m_GUID;
};
//- Guid Inline Public Methods ------------------------------------------------
inline
Guid::Guid()
: m_GUID(INVALID_GUID)
{
}
inline
Guid::Guid(uint64_t guid)
: m_GUID(guid)
{
}
inline Guid
Guid::InvalidGuid()
{
return (Guid(INVALID_GUID));
}
inline Guid&
Guid::operator=(const Guid &rhs)
{
m_GUID = rhs.m_GUID;
return (*this);
}
inline bool
Guid::IsValid() const
{
return (m_GUID != INVALID_GUID);
}
inline bool
Guid::operator==(const Guid& rhs) const
{
return (m_GUID == rhs.m_GUID);
}
inline bool
Guid::operator!=(const Guid& rhs) const
{
return (m_GUID != rhs.m_GUID);
}
inline
Guid::operator uint64_t() const
{
return (m_GUID);
}
inline
Guid::operator bool() const
{
return (m_GUID != INVALID_GUID);
}
/** Convert the GUID into its string representation */
std::ostream& operator<< (std::ostream& out, Guid g);
} // namespace DevdCtl
#endif /* _DEVDCTL_GUID_H_ */