xref: /xnu-11215/libkern/c++/OSBoolean.cpp (revision 855239e5)
1 /*
2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
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8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
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20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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27  */
28 /* OSBoolean.cpp created by rsulack on Tue Oct 12 1999 */
29 
30 #include <libkern/c++/OSBoolean.h>
31 #include <libkern/c++/OSString.h>
32 #include <libkern/c++/OSSerialize.h>
33 #include <libkern/c++/OSLib.h>
34 
35 #define super OSObject
36 
37 OSDefineMetaClassAndStructorsWithInit(OSBoolean, OSObject, OSBoolean::initialize())
38 OSMetaClassDefineReservedUnused(OSBoolean, 0);
39 OSMetaClassDefineReservedUnused(OSBoolean, 1);
40 OSMetaClassDefineReservedUnused(OSBoolean, 2);
41 OSMetaClassDefineReservedUnused(OSBoolean, 3);
42 OSMetaClassDefineReservedUnused(OSBoolean, 4);
43 OSMetaClassDefineReservedUnused(OSBoolean, 5);
44 OSMetaClassDefineReservedUnused(OSBoolean, 6);
45 OSMetaClassDefineReservedUnused(OSBoolean, 7);
46 
47 static OSBoolean * gOSBooleanTrue  = 0;
48 static OSBoolean * gOSBooleanFalse = 0;
49 
50 OSBoolean * const & kOSBooleanTrue  = gOSBooleanTrue;
51 OSBoolean * const & kOSBooleanFalse = gOSBooleanFalse;
52 
53 void OSBoolean::initialize()
54 {
55     gOSBooleanTrue = new OSBoolean;
56     assert(gOSBooleanTrue);
57 
58     if (!gOSBooleanTrue->init()) {
59         gOSBooleanTrue->OSObject::free();
60         assert(false);
61     };
62     gOSBooleanTrue->value = true;
63 
64     gOSBooleanFalse = new OSBoolean;
65     assert(gOSBooleanFalse);
66 
67     if (!gOSBooleanFalse->init()) {
68         gOSBooleanFalse->OSObject::free();
69         assert(false);
70     };
71     gOSBooleanFalse->value = false;
72 }
73 
74 void OSBoolean::free()
75 {
76     /*
77      * An OSBoolean should never have free() called on it, since it is a shared
78      * object, with two non-mutable instances: kOSBooleanTrue, kOSBooleanFalse.
79      * There will be cases where an incorrect number of releases will cause the
80      * free() method to be called, however, which we must catch and ignore here.
81      */
82     assert(false);
83 }
84 
85 void OSBoolean::taggedRetain(__unused const void *tag) const { }
86 void OSBoolean::taggedRelease(__unused const void *tag, __unused const int when) const { }
87 
88 OSBoolean *OSBoolean::withBoolean(bool inValue)
89 {
90     return (inValue) ? kOSBooleanTrue : kOSBooleanFalse;
91 }
92 
93 bool OSBoolean::isTrue() const { return value; }
94 bool OSBoolean::isFalse() const { return !value; }
95 bool OSBoolean::getValue() const { return value; }
96 
97 bool OSBoolean::isEqualTo(const OSBoolean *boolean) const
98 {
99     return (boolean == this);
100 }
101 
102 bool OSBoolean::isEqualTo(const OSMetaClassBase *obj) const
103 {
104     OSBoolean *	boolean;
105     if ((boolean = OSDynamicCast(OSBoolean, obj)))
106 	return isEqualTo(boolean);
107     else
108 	return false;
109 }
110 
111 bool OSBoolean::serialize(OSSerialize *s) const
112 {
113     return s->addString(value ? "<true/>" : "<false/>");
114 }
115