| 1 | /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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| 2 | /* ***** BEGIN LICENSE BLOCK *****
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| 3 | * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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| 4 | *
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| 5 | * The contents of this file are subject to the Mozilla Public License Version
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| 6 | * 1.1 (the "License"); you may not use this file except in compliance with
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| 7 | * the License. You may obtain a copy of the License at
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| 8 | * http://www.mozilla.org/MPL/
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| 9 | *
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| 10 | * Software distributed under the License is distributed on an "AS IS" basis,
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| 11 | * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
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| 12 | * for the specific language governing rights and limitations under the
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| 13 | * License.
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| 14 | *
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| 15 | * The Original Code is mozilla.org code.
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| 16 | *
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| 17 | * The Initial Developer of the Original Code is
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| 18 | * Netscape Communications Corporation.
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| 19 | * Portions created by the Initial Developer are Copyright (C) 1998
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| 20 | * the Initial Developer. All Rights Reserved.
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| 21 | *
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| 22 | * Contributor(s):
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| 23 | *
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| 24 | * Alternatively, the contents of this file may be used under the terms of
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| 25 | * either of the GNU General Public License Version 2 or later (the "GPL"),
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| 26 | * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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| 27 | * in which case the provisions of the GPL or the LGPL are applicable instead
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| 28 | * of those above. If you wish to allow use of your version of this file only
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| 29 | * under the terms of either the GPL or the LGPL, and not to allow others to
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| 30 | * use your version of this file under the terms of the MPL, indicate your
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| 31 | * decision by deleting the provisions above and replace them with the notice
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| 32 | * and other provisions required by the GPL or the LGPL. If you do not delete
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| 33 | * the provisions above, a recipient may use your version of this file under
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| 34 | * the terms of any one of the MPL, the GPL or the LGPL.
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| 35 | *
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| 36 | * ***** END LICENSE BLOCK ***** */
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| 37 | #ifndef nscore_h___
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| 38 | #define nscore_h___
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| 39 |
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| 40 | /**
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| 41 | * Make sure that we have the proper platform specific
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| 42 | * c++ definitions needed by nscore.h
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| 43 | */
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| 44 | #ifndef _XPCOM_CONFIG_H_
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| 45 | #include "xpcom-config.h"
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| 46 | #endif
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| 47 |
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| 48 | /**
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| 49 | * Incorporate the core NSPR data types which XPCOM uses.
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| 50 | */
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| 51 | #include "prtypes.h"
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| 52 |
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| 53 | /* Core XPCOM declarations. */
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| 54 |
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| 55 | /**
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| 56 | * Macros defining the target platform...
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| 57 | */
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| 58 | #ifdef _WIN32
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| 59 | #define NS_WIN32 1
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| 60 |
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| 61 | #elif defined(__unix)
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| 62 | #define NS_UNIX 1
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| 63 |
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| 64 | #elif defined(XP_OS2)
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| 65 | #define NS_OS2 1
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| 66 | #endif
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| 67 | /*----------------------------------------------------------------------*/
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| 68 | /* Import/export defines */
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| 69 |
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| 70 | /**
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| 71 | * Using the visibility("hidden") attribute allows the compiler to use
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| 72 | * PC-relative addressing to call this function. If a function does not
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| 73 | * access any global data, and does not call any methods which are not either
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| 74 | * file-local or hidden, then on ELF systems we avoid loading the address of
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| 75 | * the PLT into a register at the start of the function, which reduces code
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| 76 | * size and frees up a register for general use.
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| 77 | *
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| 78 | * As a general rule, this should be used for any non-exported symbol
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| 79 | * (including virtual method implementations). NS_IMETHOD uses this by
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| 80 | * default; if you need to have your NS_IMETHOD functions exported, you can
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| 81 | * wrap your class as follows:
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| 82 | *
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| 83 | * #undef IMETHOD_VISIBILITY
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| 84 | * #define IMETHOD_VISIBILITY NS_VISIBILITY_DEFAULT
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| 85 | *
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| 86 | * class Foo {
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| 87 | * ...
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| 88 | * };
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| 89 | *
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| 90 | * #undef IMETHOD_VISIBILITY
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| 91 | * #define IMETHOD_VISIBILITY NS_VISIBILITY_HIDDEN
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| 92 | *
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| 93 | * Don't forget to change the visibility back to hidden before the end
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| 94 | * of a header!
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| 95 | *
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| 96 | * Other examples:
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| 97 | *
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| 98 | * NS_HIDDEN_(int) someMethod();
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| 99 | * SomeCtor() NS_HIDDEN;
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| 100 | */
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| 101 |
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| 102 | #ifdef HAVE_VISIBILITY_ATTRIBUTE
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| 103 | #define NS_VISIBILITY_HIDDEN __attribute__ ((visibility ("hidden")))
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| 104 | # ifdef VBOX_HAVE_VISIBILITY_HIDDEN
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| 105 | # define NS_VISIBILITY_DEFAULT __attribute__ ((visibility ("default")))
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| 106 | # else
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| 107 | # define NS_VISIBILITY_DEFAULT
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| 108 | # endif
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| 109 |
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| 110 | #define NS_HIDDEN_(type) NS_VISIBILITY_HIDDEN type
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| 111 | #else
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| 112 | #define NS_VISIBILITY_HIDDEN
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| 113 | #define NS_VISIBILITY_DEFAULT
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| 114 |
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| 115 | #define NS_HIDDEN_(type) type
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| 116 | #endif
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| 117 |
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| 118 | #define NS_HIDDEN NS_VISIBILITY_HIDDEN
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| 119 |
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| 120 | #undef IMETHOD_VISIBILITY
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| 121 | #define IMETHOD_VISIBILITY NS_VISIBILITY_HIDDEN
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| 122 |
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| 123 | /**
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| 124 | * Mark a function as using a potentially non-standard function calling
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| 125 | * convention. This can be used on functions that are called very
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| 126 | * frequently, to reduce the overhead of the function call. It is still worth
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| 127 | * using the macro for C++ functions which take no parameters since it allows
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| 128 | * passing |this| in a register.
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| 129 | *
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| 130 | * - Do not use this on any scriptable interface method since xptcall won't be
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| 131 | * aware of the different calling convention.
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| 132 | * - This must appear on the declaration, not the definition.
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| 133 | * - Adding this to a public function _will_ break binary compatibility.
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| 134 | * - This may be used on virtual functions but you must ensure it is applied
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| 135 | * to all implementations - the compiler will _not_ warn but it will crash.
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| 136 | * - This has no effect for inline functions or functions which take a
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| 137 | * variable number of arguments.
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| 138 | *
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| 139 | * Examples: int NS_FASTCALL func1(char *foo);
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| 140 | * NS_HIDDEN_(int) NS_FASTCALL func2(char *foo);
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| 141 | */
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| 142 |
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| 143 | #if defined(__i386__) && defined(__GNUC__) && (__GNUC__ >= 3) && !defined(XP_OS2)
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| 144 | #define NS_FASTCALL __attribute__ ((regparm (3), stdcall))
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| 145 | #else
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| 146 | #define NS_FASTCALL
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| 147 | #endif
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| 148 |
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| 149 | /*
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| 150 | * NS_DEFCALL undoes the effect of a global regparm/stdcall setting
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| 151 | * so that xptcall works correctly.
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| 152 | */
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| 153 | #if defined(__i386__) && defined(__GNUC__) && (__GNUC__ >= 3) && !defined(XP_OS2)
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| 154 | #define NS_DEFCALL __attribute__ ((regparm (0), cdecl))
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| 155 | #else
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| 156 | #define NS_DEFCALL
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| 157 | #endif
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| 158 |
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| 159 | /* XXX: nike, maybe fix */
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| 160 | #define NS_EXPORT_STATIC_MEMBER_(type) type
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| 161 | #define NS_IMPORT_STATIC_MEMBER_(type) type
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| 162 |
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| 163 | #ifdef NS_WIN32
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| 164 |
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| 165 | #define NS_IMPORT __declspec(dllimport)
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| 166 | #define NS_IMPORT_(type) type __declspec(dllimport) __stdcall
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| 167 | #define NS_EXPORT __declspec(dllexport)
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| 168 | #define NS_EXPORT_(type) type __declspec(dllexport) __stdcall
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| 169 | #define NS_IMETHOD_(type) virtual type __stdcall
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| 170 | #define NS_IMETHODIMP_(type) type __stdcall
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| 171 | #define NS_METHOD_(type) type __stdcall
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| 172 | #define NS_CALLBACK_(_type, _name) _type (__stdcall * _name)
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| 173 | #define NS_STDCALL __stdcall
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| 174 |
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| 175 | #elif defined(XP_MAC)
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| 176 |
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| 177 | #define NS_IMPORT
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| 178 | #define NS_IMPORT_(type) type
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| 179 | #define NS_EXPORT __declspec(export)
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| 180 | #define NS_EXPORT_(type) __declspec(export) type
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| 181 | #define NS_IMETHOD_(type) virtual type
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| 182 | #define NS_IMETHODIMP_(type) type
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| 183 | #define NS_METHOD_(type) type
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| 184 | #define NS_CALLBACK_(_type, _name) _type (* _name)
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| 185 | #define NS_STDCALL
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| 186 |
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| 187 | #elif defined(XP_OS2) && defined(__declspec)
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| 188 |
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| 189 | #define NS_IMPORT __declspec(dllimport)
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| 190 | #define NS_IMPORT_(type) type __declspec(dllimport) __stdcall
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| 191 | #define NS_EXPORT __declspec(dllexport)
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| 192 | #define NS_EXPORT_(type) type __declspec(dllexport) __stdcall
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| 193 | #define NS_IMETHOD_(type) virtual IMETHOD_VISIBILITY type NS_DEFCALL
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| 194 | #define NS_IMETHODIMP_(type) type
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| 195 | #define NS_METHOD_(type) type
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| 196 | #define NS_CALLBACK_(_type, _name) _type (* _name)
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| 197 | #define NS_STDCALL
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| 198 |
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| 199 | #else
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| 200 |
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| 201 | # ifdef VBOX_HAVE_VISIBILITY_HIDDEN
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| 202 | # define NS_IMPORT
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| 203 | # define NS_IMPORT_(type) type
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| 204 | # define NS_EXPORT __attribute__((visibility("default")))
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| 205 | # define NS_EXPORT_(type) __attribute__((visibility("default"))) type
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| 206 | # define NS_IMETHOD_(type) virtual IMETHOD_VISIBILITY type NS_DEFCALL
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| 207 | # define NS_IMETHODIMP_(type) type
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| 208 | # define NS_METHOD_(type) type
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| 209 | # define NS_CALLBACK_(_type, _name) _type (* _name)
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| 210 | # define NS_STDCALL
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| 211 | # else
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| 212 | # define NS_IMPORT
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| 213 | # define NS_IMPORT_(type) type
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| 214 | # define NS_EXPORT
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| 215 | # define NS_EXPORT_(type) type
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| 216 | # define NS_IMETHOD_(type) virtual IMETHOD_VISIBILITY type NS_DEFCALL
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| 217 | # define NS_IMETHODIMP_(type) type
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| 218 | # define NS_METHOD_(type) type
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| 219 | # define NS_CALLBACK_(_type, _name) _type (* _name)
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| 220 | # define NS_STDCALL
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| 221 | # endif
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| 222 | #endif
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| 223 |
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| 224 | /**
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| 225 | * Macro for creating typedefs for pointer-to-member types which are
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| 226 | * declared with stdcall. It is important to use this for any type which is
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| 227 | * declared as stdcall (i.e. NS_IMETHOD). For example, instead of writing:
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| 228 | *
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| 229 | * typedef nsresult (nsIFoo::*someType)(nsISupports* arg);
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| 230 | *
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| 231 | * you should write:
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| 232 | *
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| 233 | * typedef
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| 234 | * NS_STDCALL_FUNCPROTO(nsresult, someType, nsIFoo, typeFunc, (nsISupports*));
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| 235 | *
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| 236 | * where nsIFoo::typeFunc is any method declared as
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| 237 | * NS_IMETHOD typeFunc(nsISupports*);
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| 238 | *
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| 239 | * XXX this can be simplified to always use the non-typeof implementation
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| 240 | * when http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11893 is fixed.
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| 241 | */
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| 242 |
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| 243 | #ifdef __GNUC__
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| 244 | #define NS_STDCALL_FUNCPROTO(ret, name, class, func, args) \
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| 245 | typeof(&class::func) name
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| 246 | #else
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| 247 | #define NS_STDCALL_FUNCPROTO(ret, name, class, func, args) \
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| 248 | ret (NS_STDCALL class::*name) args
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| 249 | #endif
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| 250 |
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| 251 | /**
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| 252 | * Generic API modifiers which return the standard XPCOM nsresult type
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| 253 | */
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| 254 | #define NS_IMETHOD NS_IMETHOD_(nsresult)
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| 255 | #define NS_IMETHODIMP NS_IMETHODIMP_(nsresult)
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| 256 | #define NS_METHOD NS_METHOD_(nsresult)
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| 257 | #define NS_CALLBACK(_name) NS_CALLBACK_(nsresult, _name)
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| 258 |
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| 259 | /**
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| 260 | * Import/Export macros for XPCOM APIs
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| 261 | */
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| 262 |
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| 263 | #ifdef _IMPL_NS_COM
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| 264 | #define NS_COM NS_EXPORT
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| 265 | #elif _IMPL_NS_COM_OFF
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| 266 | #define NS_COM
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| 267 | #elif XPCOM_GLUE
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| 268 | #define NS_COM
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| 269 | #else
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| 270 | #define NS_COM NS_IMPORT
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| 271 | #endif
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| 272 |
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| 273 |
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| 274 | /**
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| 275 | * NS_NO_VTABLE is emitted by xpidl in interface declarations whenever
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| 276 | * xpidl can determine that the interface can't contain a constructor.
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| 277 | * This results in some space savings and possible runtime savings -
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| 278 | * see bug 49416. We undefine it first, as xpidl-generated headers
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| 279 | * define it for IDL uses that don't include this file.
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| 280 | */
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| 281 | #ifdef NS_NO_VTABLE
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| 282 | #undef NS_NO_VTABLE
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| 283 | #endif
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| 284 | #if defined(_MSC_VER) && _MSC_VER >= 1100
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| 285 | #define NS_NO_VTABLE __declspec(novtable)
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| 286 | #else
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| 287 | #define NS_NO_VTABLE
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| 288 | #endif
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| 289 |
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| 290 |
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| 291 | /**
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| 292 | * Generic XPCOM result data type
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| 293 | */
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| 294 | typedef PRUint32 nsresult;
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| 295 |
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| 296 | /**
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| 297 | * The preferred symbol for null.
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| 298 | */
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| 299 | #define nsnull 0
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| 300 |
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| 301 | #include "nsError.h"
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| 302 |
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| 303 | /* ------------------------------------------------------------------------ */
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| 304 | /* Casting macros for hiding C++ features from older compilers */
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| 305 |
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| 306 | /*
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| 307 | All our compiler support template specialization, but not all support the
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| 308 | |template <>| notation. The compiler that don't understand this notation
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| 309 | just omit it for specialization.
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| 310 |
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| 311 | Need to add an autoconf test for this.
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| 312 | */
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| 313 |
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| 314 | /* under Metrowerks (Mac), we don't have autoconf yet */
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| 315 | #ifdef __MWERKS__
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| 316 | #define HAVE_CPP_PARTIAL_SPECIALIZATION
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| 317 | #define HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
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| 318 |
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| 319 | #define HAVE_CPP_ACCESS_CHANGING_USING
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| 320 | #define HAVE_CPP_AMBIGUITY_RESOLVING_USING
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| 321 | #define HAVE_CPP_EXPLICIT
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| 322 | #define HAVE_CPP_TYPENAME
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| 323 | #define HAVE_CPP_BOOL
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| 324 | #define HAVE_CPP_NAMESPACE_STD
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| 325 | #define HAVE_CPP_UNAMBIGUOUS_STD_NOTEQUAL
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| 326 | #define HAVE_CPP_2BYTE_WCHAR_T
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| 327 | #endif
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| 328 |
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| 329 | /* under VC++ (Windows), we don't have autoconf yet */
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| 330 | #if defined(_MSC_VER) && (_MSC_VER>=1100)
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| 331 | /* VC++ 5.0 and greater implement template specialization, 4.2 is unknown */
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| 332 | #define HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
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| 333 |
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| 334 | #define HAVE_CPP_EXPLICIT
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| 335 | #define HAVE_CPP_TYPENAME
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| 336 | #define HAVE_CPP_ACCESS_CHANGING_USING
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| 337 |
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| 338 | #if (_MSC_VER==1100)
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| 339 | /* VC++5.0 has an internal compiler error (sometimes) without this */
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| 340 | #undef HAVE_CPP_ACCESS_CHANGING_USING
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| 341 | #endif
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| 342 |
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| 343 | #define HAVE_CPP_NAMESPACE_STD
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| 344 | #define HAVE_CPP_UNAMBIGUOUS_STD_NOTEQUAL
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| 345 | #define HAVE_CPP_2BYTE_WCHAR_T
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| 346 | #endif
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| 347 |
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| 348 | #ifndef __PRUNICHAR__
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| 349 | #define __PRUNICHAR__
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| 350 | /* For now, don't use wchar_t on Unix because it breaks the Netscape
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| 351 | * commercial build. When this is fixed there will be no need for the
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| 352 | * |NS_REINTERPRET_CAST| in nsLiteralString.h either.
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| 353 | */
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| 354 | #if defined(HAVE_CPP_2BYTE_WCHAR_T) && (defined(NS_WIN32) || defined(XP_MAC))
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| 355 | typedef wchar_t PRUnichar;
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| 356 | #else
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| 357 | typedef PRUint16 PRUnichar;
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| 358 | #endif
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| 359 | #endif
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| 360 |
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| 361 | /*
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| 362 | If the compiler doesn't support |explicit|, we'll just make it go away, trusting
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| 363 | that the builds under compilers that do have it will keep us on the straight and narrow.
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| 364 | */
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| 365 | #ifndef HAVE_CPP_EXPLICIT
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| 366 | #define explicit
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| 367 | #endif
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| 368 |
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| 369 | #ifndef HAVE_CPP_TYPENAME
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| 370 | #define typename
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| 371 | #endif
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| 372 |
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| 373 | #ifdef HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
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| 374 | #define NS_SPECIALIZE_TEMPLATE template <>
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| 375 | #else
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| 376 | #define NS_SPECIALIZE_TEMPLATE
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| 377 | #endif
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| 378 |
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| 379 | /* unix and beos now determine this automatically */
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| 380 | #if ! defined XP_UNIX && ! defined XP_BEOS && !defined(XP_OS2)
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| 381 | #ifndef HAVE_CPP_NEW_CASTS
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| 382 | #define HAVE_CPP_NEW_CASTS 1 /* we'll be optimistic. */
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| 383 | #endif
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| 384 | #endif
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| 385 |
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| 386 | #if defined(HAVE_CPP_NEW_CASTS)
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| 387 | #define NS_STATIC_CAST(__type, __ptr) static_cast< __type >(__ptr)
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| 388 | #define NS_CONST_CAST(__type, __ptr) const_cast< __type >(__ptr)
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| 389 |
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| 390 | #define NS_REINTERPRET_POINTER_CAST(__type, __ptr) reinterpret_cast< __type >(__ptr)
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| 391 | #define NS_REINTERPRET_NONPOINTER_CAST(__type, __obj) reinterpret_cast< __type >(__obj)
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| 392 | #define NS_REINTERPRET_CAST(__type, __expr) reinterpret_cast< __type >(__expr)
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| 393 |
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| 394 | #else
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| 395 | #define NS_STATIC_CAST(__type, __ptr) ((__type)(__ptr))
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| 396 | #define NS_CONST_CAST(__type, __ptr) ((__type)(__ptr))
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| 397 |
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| 398 | #define NS_REINTERPRET_POINTER_CAST(__type, __ptr) ((__type)((void*)(__ptr)))
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| 399 | #define NS_REINTERPRET_NONPOINTER_CAST(__type, __obj) ((__type)(__obj))
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| 400 |
|
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| 401 | /* Note: the following is only appropriate for pointers. */
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| 402 | #define NS_REINTERPRET_CAST(__type, __expr) NS_REINTERPRET_POINTER_CAST(__type, __expr)
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| 403 | /*
|
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| 404 | Why cast to a |void*| first? Well, when old-style casting from
|
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| 405 | a pointer to a base to a pointer to a derived class, the cast will be
|
|---|
| 406 | ambiguous if the source pointer type appears multiple times in the
|
|---|
| 407 | destination, e.g.,
|
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| 408 |
|
|---|
| 409 | class Base {};
|
|---|
| 410 | class Derived : public Base, public Base {};
|
|---|
| 411 |
|
|---|
| 412 | void foo( Base* b )
|
|---|
| 413 | {
|
|---|
| 414 | ((Derived*)b)->some_derived_member ... // Error: Ambiguous, expand from which |Base|?
|
|---|
| 415 | }
|
|---|
| 416 |
|
|---|
| 417 | an old-style cast (like |static_cast|) will change the pointer, but
|
|---|
| 418 | here, doesn't know how. The cast to |void*| prevents it from thinking
|
|---|
| 419 | it needs to expand the original pointer.
|
|---|
| 420 |
|
|---|
| 421 | The cost is, |NS_REINTERPRET_CAST| is no longer appropriate for non-pointer
|
|---|
| 422 | conversions. Also, mis-applying |NS_REINTERPRET_CAST| to cast |this| to something
|
|---|
| 423 | will still expand the pointer to the outer object in standards complying compilers.
|
|---|
| 424 | */
|
|---|
| 425 |
|
|---|
| 426 | /*
|
|---|
| 427 | No sense in making an NS_DYNAMIC_CAST() macro: you can't duplicate
|
|---|
| 428 | the semantics. So if you want to dynamic_cast, then just use it
|
|---|
| 429 | "straight", no macro.
|
|---|
| 430 | */
|
|---|
| 431 | #endif
|
|---|
| 432 |
|
|---|
| 433 | /*
|
|---|
| 434 | * Use these macros to do 64bit safe pointer conversions.
|
|---|
| 435 | */
|
|---|
| 436 |
|
|---|
| 437 | #define NS_PTR_TO_INT32(x) ((char *)(x) - (char *)0)
|
|---|
| 438 | #define NS_INT32_TO_PTR(x) ((void *)((char *)0 + (x)))
|
|---|
| 439 |
|
|---|
| 440 | /*
|
|---|
| 441 | * These macros allow you to give a hint to the compiler about branch
|
|---|
| 442 | * probability so that it can better optimize. Use them like this:
|
|---|
| 443 | *
|
|---|
| 444 | * if (NS_LIKELY(v == 1)) {
|
|---|
| 445 | * ... expected code path ...
|
|---|
| 446 | * }
|
|---|
| 447 | *
|
|---|
| 448 | * if (NS_UNLIKELY(v == 0)) {
|
|---|
| 449 | * ... non-expected code path ...
|
|---|
| 450 | * }
|
|---|
| 451 | *
|
|---|
| 452 | */
|
|---|
| 453 |
|
|---|
| 454 | #if defined(__GNUC__) && (__GNUC__ > 2)
|
|---|
| 455 | #define NS_LIKELY(x) (__builtin_expect((x), 1))
|
|---|
| 456 | #define NS_UNLIKELY(x) (__builtin_expect((x), 0))
|
|---|
| 457 | #else
|
|---|
| 458 | #define NS_LIKELY(x) (x)
|
|---|
| 459 | #define NS_UNLIKELY(x) (x)
|
|---|
| 460 | #endif
|
|---|
| 461 |
|
|---|
| 462 | #endif /* nscore_h___ */
|
|---|
| 463 |
|
|---|
