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
Guid()93 Guid::Guid()
94 : m_GUID(INVALID_GUID)
95 {
96 }
97
98 inline
Guid(uint64_t guid)99 Guid::Guid(uint64_t guid)
100 : m_GUID(guid)
101 {
102 }
103
104 inline Guid
InvalidGuid()105 Guid::InvalidGuid()
106 {
107 return (Guid(INVALID_GUID));
108 }
109
110 inline bool
IsValid()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
uint64_t()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