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 33 /** 34 * \file devdctl_guid.h 35 * 36 * Definition of the Guid class. 37 */ 38 #ifndef _DEVDCTL_GUID_H_ 39 #define _DEVDCTL_GUID_H_ 40 41 /*============================ Namespace Control =============================*/ 42 namespace DevdCtl 43 { 44 45 /*============================= Class Definitions ============================*/ 46 /*----------------------------------- Guid -----------------------------------*/ 47 /** 48 * \brief Object that represents guids. 49 * 50 * It can generally be manipulated as a uint64_t, but with a special 51 * value INVALID_GUID that does not equal any valid guid. 52 * 53 * As of this writing, this class is only used to represent ZFS 54 * guids in events and spa_generate_guid() in spa_misc.c explicitly 55 * refuses to return a guid of 0. So this class uses 0 as the value 56 * for INVALID_GUID. In the future, if 0 is allowed to be a valid 57 * guid, the implementation of this class must change. 58 */ 59 class Guid 60 { 61 public: 62 /* Constructors */ 63 /* Default constructor: an Invalid guid */ 64 Guid(); 65 /* Construct a guid from a provided integer */ 66 Guid(uint64_t guid); 67 /* Construct a guid from a string in base 8, 10, or 16 */ 68 Guid(const std::string &guid); 69 static Guid InvalidGuid(); 70 71 /* Test the validity of this guid. */ 72 bool IsValid() const; 73 74 /* Comparison to other Guid operators */ 75 bool operator==(const Guid& rhs) const; 76 bool operator!=(const Guid& rhs) const; 77 78 /* Integer conversion operators */ 79 operator uint64_t() const; 80 operator bool() const; 81 82 protected: 83 static const uint64_t INVALID_GUID = 0; 84 85 /* The integer value of the GUID. */ 86 uint64_t m_GUID; 87 }; 88 89 //- Guid Inline Public Methods ------------------------------------------------ 90 inline 91 Guid::Guid() 92 : m_GUID(INVALID_GUID) 93 { 94 } 95 96 inline 97 Guid::Guid(uint64_t guid) 98 : m_GUID(guid) 99 { 100 } 101 102 inline Guid 103 Guid::InvalidGuid() 104 { 105 return (Guid(INVALID_GUID)); 106 } 107 108 inline bool 109 Guid::IsValid() const 110 { 111 return (m_GUID != INVALID_GUID); 112 } 113 114 inline bool 115 Guid::operator==(const Guid& rhs) const 116 { 117 return (m_GUID == rhs.m_GUID); 118 } 119 120 inline bool 121 Guid::operator!=(const Guid& rhs) const 122 { 123 return (m_GUID != rhs.m_GUID); 124 } 125 126 inline 127 Guid::operator uint64_t() const 128 { 129 return (m_GUID); 130 } 131 132 inline 133 Guid::operator bool() const 134 { 135 return (m_GUID != INVALID_GUID); 136 } 137 138 /** Convert the GUID into its string representation */ 139 std::ostream& operator<< (std::ostream& out, Guid g); 140 141 } // namespace DevdCtl 142 #endif /* _DEVDCTL_GUID_H_ */ 143