1 | /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
|
---|
2 | /* ***** BEGIN LICENSE BLOCK *****
|
---|
3 | * Version: MPL 1.1/GPL 2.0/LGPL 2.1
|
---|
4 | *
|
---|
5 | * The contents of this file are subject to the Mozilla Public License Version
|
---|
6 | * 1.1 (the "License"); you may not use this file except in compliance with
|
---|
7 | * the License. You may obtain a copy of the License at
|
---|
8 | * http://www.mozilla.org/MPL/
|
---|
9 | *
|
---|
10 | * Software distributed under the License is distributed on an "AS IS" basis,
|
---|
11 | * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
|
---|
12 | * for the specific language governing rights and limitations under the
|
---|
13 | * License.
|
---|
14 | *
|
---|
15 | * The Original Code is Mozilla FastLoad code.
|
---|
16 | *
|
---|
17 | * The Initial Developer of the Original Code is
|
---|
18 | * Netscape Communications Corporation.
|
---|
19 | * Portions created by the Initial Developer are Copyright (C) 2001
|
---|
20 | * the Initial Developer. All Rights Reserved.
|
---|
21 | *
|
---|
22 | * Contributor(s):
|
---|
23 | * Brendan Eich <[email protected]> (original author)
|
---|
24 | *
|
---|
25 | * Alternatively, the contents of this file may be used under the terms of
|
---|
26 | * either of the GNU General Public License Version 2 or later (the "GPL"),
|
---|
27 | * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
|
---|
28 | * in which case the provisions of the GPL or the LGPL are applicable instead
|
---|
29 | * of those above. If you wish to allow use of your version of this file only
|
---|
30 | * under the terms of either the GPL or the LGPL, and not to allow others to
|
---|
31 | * use your version of this file under the terms of the MPL, indicate your
|
---|
32 | * decision by deleting the provisions above and replace them with the notice
|
---|
33 | * and other provisions required by the GPL or the LGPL. If you do not delete
|
---|
34 | * the provisions above, a recipient may use your version of this file under
|
---|
35 | * the terms of any one of the MPL, the GPL or the LGPL.
|
---|
36 | *
|
---|
37 | * ***** END LICENSE BLOCK ***** */
|
---|
38 |
|
---|
39 | #ifndef nsFastLoadPtr_h___
|
---|
40 | #define nsFastLoadPtr_h___
|
---|
41 |
|
---|
42 | /**
|
---|
43 | * Mozilla FastLoad file object pointer template type.
|
---|
44 | *
|
---|
45 | * Use nsFastLoadPtr<T> rather than nsCOMPtr<T> when declaring a strong XPCOM
|
---|
46 | * ref member of a data structure that's conditionally loaded at application
|
---|
47 | * startup. You must be willing to tolerate the null mRawPtr test on every
|
---|
48 | * dereference of this member pointer, or else copy it to a local to optimize
|
---|
49 | * away the cost.
|
---|
50 | */
|
---|
51 |
|
---|
52 | #ifndef nsCOMPtr_h___
|
---|
53 | #include "nsCOMPtr.h"
|
---|
54 | #endif
|
---|
55 |
|
---|
56 | #ifndef nsIFastLoadService_h___
|
---|
57 | #include "nsIFastLoadService.h"
|
---|
58 | #endif
|
---|
59 |
|
---|
60 | /**
|
---|
61 | * nsFastLoadPtr is a template class, so we don't want a class static service
|
---|
62 | * pointer member declared in nsFastLoadPtr, above. Plus, we need special
|
---|
63 | * declaration magic to export data across DLL/DSO boundaries. So we use an
|
---|
64 | * old-fashioned global variable that refers weakly to the one true FastLoad
|
---|
65 | * service. This pointer is maintained by that singleton's ctor and dtor.
|
---|
66 | */
|
---|
67 | PR_EXPORT_DATA(nsIFastLoadService*) gFastLoadService_;
|
---|
68 |
|
---|
69 | template <class T>
|
---|
70 | class nsFastLoadPtr : public nsCOMPtr<T> {
|
---|
71 | public:
|
---|
72 | nsDerivedSafe<T>* get() const {
|
---|
73 | if (!this->mRawPtr) {
|
---|
74 | gFastLoadService_->GetFastLoadReferent(
|
---|
75 | NS_REINTERPRET_CAST(nsISupports**,
|
---|
76 | &this->mRawPtr));
|
---|
77 | }
|
---|
78 | return NS_REINTERPRET_CAST(nsDerivedSafe<T>*, this->mRawPtr);
|
---|
79 | }
|
---|
80 |
|
---|
81 | /**
|
---|
82 | * Deserialize an nsFastLoadPtr from aInputStream, skipping the referent
|
---|
83 | * object, but saving the object's offset for later deserialization.
|
---|
84 | *
|
---|
85 | * Lowercase name _a la_ get, because it's called the same way -- not via
|
---|
86 | * operator->().
|
---|
87 | */
|
---|
88 | nsresult read(nsIObjectInputStream* aInputStream) {
|
---|
89 | return gFastLoadService_->ReadFastLoadPtr(aInputStream,
|
---|
90 | NS_REINTERPRET_CAST(nsISupports**,
|
---|
91 | &this->mRawPtr));
|
---|
92 | }
|
---|
93 |
|
---|
94 | /**
|
---|
95 | * Serialize an nsFastLoadPtr reference and possibly the referent object,
|
---|
96 | * if that object has not yet been serialized.
|
---|
97 | *
|
---|
98 | * Lowercase name _a la_ get, because it's called the same way -- not via
|
---|
99 | * operator->().
|
---|
100 | */
|
---|
101 | nsresult write(nsIObjectOutputStream* aOutputStream) {
|
---|
102 | return gFastLoadService_->WriteFastLoadPtr(aOutputStream,
|
---|
103 | NS_REINTERPRET_CAST(nsISupports*,
|
---|
104 | this->mRawPtr));
|
---|
105 | }
|
---|
106 | };
|
---|
107 |
|
---|
108 | #endif // nsFastLoadPtr_h___
|
---|