1 /*
2  * Copyright (C) 2010 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 INC. AND ITS CONTRIBUTORS ``AS IS''
14  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
15  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
16  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
17  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
18  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
19  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
20  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
21  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
22  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
23  * THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #ifndef MessageID_h
27 #define MessageID_h
28 
29 namespace CoreIPC {
30 
31 enum MessageClass {
32     MessageClassReserved = 0,
33 
34     // Messages sent by Core IPC.
35     MessageClassCoreIPC,
36 
37     // Messages sent by the UI process to the web process.
38     MessageClassAuthenticationManager,
39     MessageClassDrawingArea,
40     MessageClassDrawingAreaLegacy,
41     MessageClassInjectedBundle,
42     MessageClassWebApplicationCacheManager,
43     MessageClassWebCookieManager,
44     MessageClassWebDatabaseManager,
45     MessageClassWebFullScreenManager,
46     MessageClassWebGeolocationManagerProxy,
47     MessageClassWebIconDatabaseProxy,
48     MessageClassWebInspector,
49     MessageClassWebKeyValueStorageManager,
50     MessageClassWebMediaCacheManager,
51     MessageClassWebPage,
52     MessageClassWebProcess,
53     MessageClassWebResourceCacheManager,
54 
55     // Messages sent by the web process to the UI process.
56     MessageClassDownloadProxy,
57     MessageClassDrawingAreaProxy,
58     MessageClassDrawingAreaProxyLegacy,
59     MessageClassWebApplicationCacheManagerProxy,
60     MessageClassWebContext,
61     MessageClassWebContextLegacy,
62     MessageClassWebCookieManagerProxy,
63     MessageClassWebDatabaseManagerProxy,
64     MessageClassWebFullScreenManagerProxy,
65     MessageClassWebGeolocationManager,
66     MessageClassWebIconDatabase,
67     MessageClassWebInspectorProxy,
68     MessageClassWebKeyValueStorageManagerProxy,
69     MessageClassWebMediaCacheManagerProxy,
70     MessageClassWebPageProxy,
71     MessageClassWebProcessProxy,
72     MessageClassWebResourceCacheManagerProxy,
73 
74     // Messages sent by the UI process to the plug-in process.
75     MessageClassPluginProcess,
76 
77     // Messages sent by the plug-in process to the UI process.
78     MessageClassPluginProcessProxy,
79 
80     // Messages sent by the web process to the plug-in process.
81     MessageClassWebProcessConnection,
82     MessageClassPluginControllerProxy,
83 
84     // Messages sent by the plug-in process to the web process.
85     MessageClassPluginProxy,
86 
87     // NPObject messages sent by both the plug-in process and the web process.
88     MessageClassNPObjectMessageReceiver,
89 };
90 
91 template<typename> struct MessageKindTraits { };
92 
93 
94 /*
95     MessageID Layout (the most significant bit is reserved and therefore always zero)
96 
97     ---------
98     | Flags | 7 bits
99     |-------|
100     | Class | 8 bits
101     |-------|
102     |  Msg  | 16 bits
103     |  Kind |
104     ---------
105 */
106 
107 class MessageID {
108 public:
109     enum Flags {
110         SyncMessage = 1 << 0,
111         DispatchMessageWhenWaitingForSyncReply = 1 << 1,
112     };
113 
MessageID()114     MessageID()
115         : m_messageID(0)
116     {
117     }
118 
119     template <typename EnumType>
120     explicit MessageID(EnumType messageKind, unsigned char flags = 0)
121         : m_messageID(stripMostSignificantBit(flags << 24 | (MessageKindTraits<EnumType>::messageClass) << 16 | messageKind))
122     {
123     }
124 
messageIDWithAddedFlags(unsigned char flags)125     MessageID messageIDWithAddedFlags(unsigned char flags)
126     {
127         MessageID messageID;
128 
129         messageID.m_messageID = stripMostSignificantBit(m_messageID | (flags << 24));
130         return messageID;
131     }
132 
133     template <typename EnumType>
get()134     EnumType get() const
135     {
136         ASSERT(getClass() == MessageKindTraits<EnumType>::messageClass);
137         return static_cast<EnumType>(m_messageID & 0xffff);
138     }
139 
140     template <MessageClass K>
is()141     bool is() const
142     {
143         return getClass() == K;
144     }
145 
146     template <typename EnumType>
147     bool operator==(EnumType messageKind) const
148     {
149         return m_messageID == MessageID(messageKind).m_messageID;
150     }
151 
fromInt(unsigned i)152     static MessageID fromInt(unsigned i)
153     {
154         MessageID messageID;
155         messageID.m_messageID = stripMostSignificantBit(i);
156 
157         return messageID;
158     }
159 
toInt()160     unsigned toInt() const { return m_messageID; }
161 
shouldDispatchMessageWhenWaitingForSyncReply()162     bool shouldDispatchMessageWhenWaitingForSyncReply() const { return getFlags() & DispatchMessageWhenWaitingForSyncReply; }
isSync()163     bool isSync() const { return getFlags() & SyncMessage; }
164 
165 private:
stripMostSignificantBit(unsigned value)166     static inline unsigned stripMostSignificantBit(unsigned value)
167     {
168         return value & 0x7fffffff;
169     }
170 
getFlags()171     unsigned char getFlags() const { return (m_messageID & 0xff000000) >> 24; }
getClass()172     unsigned char getClass() const { return (m_messageID & 0x00ff0000) >> 16; }
173 
174     unsigned m_messageID;
175 };
176 
177 } // namespace CoreIPC
178 
179 #endif // MessageID_h
180