1 /*- 2 * Copyright (c) 2012, 2013 Spectra Logic Corporation 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions, and the following disclaimer, 10 * without modification. 11 * 2. Redistributions in binary form must reproduce at minimum a disclaimer 12 * substantially similar to the "NO WARRANTY" disclaimer below 13 * ("Disclaimer") and any redistribution must be conditioned upon 14 * including a substantially similar Disclaimer requirement for further 15 * binary redistribution. 16 * 17 * NO WARRANTY 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 26 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 27 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 * POSSIBILITY OF SUCH DAMAGES. 29 * 30 * Authors: Alan Somers (Spectra Logic Corporation) 31 * 32 * $FreeBSD$ 33 */ 34 35 /** 36 * \file devdctl_guid.h 37 * 38 * Definition of the Guid class. 39 */ 40 #ifndef _DEVDCTL_GUID_H_ 41 #define _DEVDCTL_GUID_H_ 42 43 /*============================ Namespace Control =============================*/ 44 namespace DevdCtl 45 { 46 47 /*============================= Class Definitions ============================*/ 48 /*----------------------------------- Guid -----------------------------------*/ 49 /** 50 * \brief Object that represents guids. 51 * 52 * It can generally be manipulated as a uint64_t, but with a special 53 * value INVALID_GUID that does not equal any valid guid. 54 * 55 * As of this writing, this class is only used to represent ZFS 56 * guids in events and spa_generate_guid() in spa_misc.c explicitly 57 * refuses to return a guid of 0. So this class uses 0 as the value 58 * for INVALID_GUID. In the future, if 0 is allowed to be a valid 59 * guid, the implementation of this class must change. 60 */ 61 class Guid 62 { 63 public: 64 /* Constructors */ 65 /* Default constructor: an Invalid guid */ 66 Guid(); 67 /* Construct a guid from a provided integer */ 68 Guid(uint64_t guid); 69 /* Construct a guid from a string in base 8, 10, or 16 */ 70 Guid(const std::string &guid); 71 static Guid InvalidGuid(); 72 73 /* Test the validity of this guid. */ 74 bool IsValid() const; 75 76 /* Comparison to other Guid operators */ 77 bool operator==(const Guid& rhs) const; 78 bool operator!=(const Guid& rhs) const; 79 80 /* Integer conversion operators */ 81 operator uint64_t() const; 82 operator bool() const; 83 84 protected: 85 static const uint64_t INVALID_GUID = 0; 86 87 /* The integer value of the GUID. */ 88 uint64_t m_GUID; 89 }; 90 91 //- Guid Inline Public Methods ------------------------------------------------ 92 inline 93 Guid::Guid() 94 : m_GUID(INVALID_GUID) 95 { 96 } 97 98 inline 99 Guid::Guid(uint64_t guid) 100 : m_GUID(guid) 101 { 102 } 103 104 inline Guid 105 Guid::InvalidGuid() 106 { 107 return (Guid(INVALID_GUID)); 108 } 109 110 inline bool 111 Guid::IsValid() const 112 { 113 return (m_GUID != INVALID_GUID); 114 } 115 116 inline bool 117 Guid::operator==(const Guid& rhs) const 118 { 119 return (m_GUID == rhs.m_GUID); 120 } 121 122 inline bool 123 Guid::operator!=(const Guid& rhs) const 124 { 125 return (m_GUID != rhs.m_GUID); 126 } 127 128 inline 129 Guid::operator uint64_t() const 130 { 131 return (m_GUID); 132 } 133 134 inline 135 Guid::operator bool() const 136 { 137 return (m_GUID != INVALID_GUID); 138 } 139 140 /** Convert the GUID into its string representation */ 141 std::ostream& operator<< (std::ostream& out, Guid g); 142 143 } // namespace DevdCtl 144 #endif /* _DEVDCTL_GUID_H_ */ 145