1 /*
2  * Copyright (C) 2009 Apple Inc. All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #ifndef IdentifierRep_h
27 #define IdentifierRep_h
28 
29 #include <wtf/Assertions.h>
30 #include <wtf/FastAllocBase.h>
31 #include <wtf/StringExtras.h>
32 #include <string.h>
33 
34 namespace WebCore {
35 
36 class IdentifierRep {
37     WTF_MAKE_FAST_ALLOCATED;
38 public:
39     static IdentifierRep* get(int);
40     static IdentifierRep* get(const char*);
41 
42     static bool isValid(IdentifierRep*);
43 
isString()44     bool isString() const { return m_isString; }
45 
number()46     int number() const { return m_isString ? 0 : m_value.m_number; }
string()47     const char* string() const { return m_isString ? m_value.m_string : 0; }
48 
49 private:
IdentifierRep(int number)50     IdentifierRep(int number)
51         : m_isString(false)
52     {
53         m_value.m_number = number;
54     }
55 
IdentifierRep(const char * name)56     IdentifierRep(const char* name)
57         : m_isString(true)
58     {
59         m_value.m_string = fastStrDup(name);
60     }
61 
~IdentifierRep()62     ~IdentifierRep()
63     {
64         // IdentifierReps should never be deleted.
65         ASSERT_NOT_REACHED();
66     }
67 
68     union {
69         const char* m_string;
70         int m_number;
71     } m_value;
72     bool m_isString;
73 };
74 
75 } // namespace WebCore
76 
77 #endif // IdentifierRep_h
78