summaryrefslogtreecommitdiffstats
path: root/xpcom/glue/nsID.h
blob: c04007d4e9bf168936ca15722d533d62ecfb8f62 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#ifndef nsID_h__
#define nsID_h__

#include <string.h>

#include "nscore.h"

#define NSID_LENGTH 39

/**
 * A "unique identifier". This is modeled after OSF DCE UUIDs.
 */

struct nsID
{
  /**
   * @name Identifier values
   */

  //@{
  uint32_t m0;
  uint16_t m1;
  uint16_t m2;
  uint8_t m3[8];
  //@}

  /**
   * @name Methods
   */

  //@{
  /**
   * Ensures everything is zeroed out.
   */
  void Clear();

  /**
   * Equivalency method. Compares this nsID with another.
   * @return <b>true</b> if they are the same, <b>false</b> if not.
   */

  inline bool Equals(const nsID& aOther) const
  {
    // Unfortunately memcmp isn't faster than this.
    return
      (((uint32_t*)&m0)[0] == ((uint32_t*)&aOther.m0)[0]) &&
      (((uint32_t*)&m0)[1] == ((uint32_t*)&aOther.m0)[1]) &&
      (((uint32_t*)&m0)[2] == ((uint32_t*)&aOther.m0)[2]) &&
      (((uint32_t*)&m0)[3] == ((uint32_t*)&aOther.m0)[3]);
  }

  inline bool operator==(const nsID& aOther) const
  {
    return Equals(aOther);
  }

  /**
   * nsID Parsing method. Turns a {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx}
   * string into an nsID
   */
  bool Parse(const char* aIDStr);

#ifndef XPCOM_GLUE_AVOID_NSPR
  /**
   * nsID string encoder. Returns an allocated string in
   * {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} format. Caller should free string.
   * YOU SHOULD ONLY USE THIS IF YOU CANNOT USE ToProvidedString() BELOW.
   */
  char* ToString() const;

  /**
   * nsID string encoder. Builds a string in
   * {xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx} format, into a char[NSID_LENGTH]
   * buffer provided by the caller (for instance, on the stack).
   */
  void ToProvidedString(char (&aDest)[NSID_LENGTH]) const;

#endif // XPCOM_GLUE_AVOID_NSPR

  //@}
};

#ifndef XPCOM_GLUE_AVOID_NSPR
/**
 * A stack helper class to convert a nsID to a string.  Useful
 * for printing nsIDs.  For example:
 *   nsID aID = ...;
 *   printf("%s", nsIDToCString(aID).get());
 */
class nsIDToCString
{
public:
  explicit nsIDToCString(const nsID& aID)
  {
    aID.ToProvidedString(mStringBytes);
  }

  const char *get() const
  {
    return mStringBytes;
  }

protected:
  char mStringBytes[NSID_LENGTH];
};
#endif

/*
 * Class IDs
 */

typedef nsID nsCID;

// Define an CID
#define NS_DEFINE_CID(_name, _cidspec) \
  const nsCID _name = _cidspec

#define NS_DEFINE_NAMED_CID(_name) \
  static const nsCID k##_name = _name

#define REFNSCID const nsCID&

/**
 * An "interface id" which can be used to uniquely identify a given
 * interface.
 */

typedef nsID nsIID;

/**
 * A macro shorthand for <tt>const nsIID&<tt>
 */

#define REFNSIID const nsIID&

/**
 * Define an IID
 * obsolete - do not use this macro
 */

#define NS_DEFINE_IID(_name, _iidspec) \
  const nsIID _name = _iidspec

/**
 * A macro to build the static const IID accessor method. The Dummy
 * template parameter only exists so that the kIID symbol will be linked
 * properly (weak symbol on linux, gnu_linkonce on mac, multiple-definitions
 * merged on windows). Dummy should always be instantiated as "void".
 */

#define NS_DECLARE_STATIC_IID_ACCESSOR(the_iid)                         \
  template<typename T, typename U>                                      \
  struct COMTypeInfo;

#define NS_DEFINE_STATIC_IID_ACCESSOR(the_interface, the_iid)           \
  template<typename T>                                                  \
  struct the_interface::COMTypeInfo<the_interface, T> {                 \
    static const nsIID kIID NS_HIDDEN;                                  \
  };                                                                    \
  template<typename T>                                                  \
  const nsIID the_interface::COMTypeInfo<the_interface, T>::kIID NS_HIDDEN = the_iid;

/**
 * A macro to build the static const CID accessor method
 */

#define NS_DEFINE_STATIC_CID_ACCESSOR(the_cid) \
  static const nsID& GetCID() {static const nsID cid = the_cid; return cid;}

#define NS_GET_IID(T) (T::COMTypeInfo<T, void>::kIID)
#define NS_GET_TEMPLATE_IID(T) (T::template COMTypeInfo<T, void>::kIID)

#endif