Version 1.8 of gecko-sdk. Downloaded from here:...

gecko-sdk/include/nscore.h

+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* ***** BEGIN LICENSE BLOCK *****
+ * Version: MPL 1.1/GPL 2.0/LGPL 2.1
+ *
+ * The contents of this file are subject to the Mozilla Public License Version
+ * 1.1 (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
+ * for the specific language governing rights and limitations under the
+ * License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is
+ * Netscape Communications Corporation.
+ * Portions created by the Initial Developer are Copyright (C) 1998
+ * the Initial Developer. All Rights Reserved.
+ *
+ * Contributor(s):
+ *
+ * Alternatively, the contents of this file may be used under the terms of
+ * either of the GNU General Public License Version 2 or later (the "GPL"),
+ * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
+ * in which case the provisions of the GPL or the LGPL are applicable instead
+ * of those above. If you wish to allow use of your version of this file only
+ * under the terms of either the GPL or the LGPL, and not to allow others to
+ * use your version of this file under the terms of the MPL, indicate your
+ * decision by deleting the provisions above and replace them with the notice
+ * and other provisions required by the GPL or the LGPL. If you do not delete
+ * the provisions above, a recipient may use your version of this file under
+ * the terms of any one of the MPL, the GPL or the LGPL.
+ *
+ * ***** END LICENSE BLOCK ***** */
+#ifndef nscore_h___
+#define nscore_h___
+
+/**
+ * Make sure that we have the proper platform specific 
+ * c++ definitions needed by nscore.h
+ */
+#ifndef _XPCOM_CONFIG_H_
+#include "xpcom-config.h"
+#endif
+
+/**
+ * Incorporate the core NSPR data types which XPCOM uses.
+ */
+#include "prtypes.h"
+
+/* Core XPCOM declarations. */
+
+/**
+ * Macros defining the target platform...
+ */
+#ifdef _WIN32
+#define NS_WIN32 1
+
+#elif defined(__unix)
+#define NS_UNIX 1
+
+#elif defined(XP_OS2)
+#define NS_OS2 1
+#endif
+/*----------------------------------------------------------------------*/
+/* Import/export defines */
+
+/**
+ * Using the visibility("hidden") attribute allows the compiler to use
+ * PC-relative addressing to call this function.  If a function does not
+ * access any global data, and does not call any methods which are not either
+ * file-local or hidden, then on ELF systems we avoid loading the address of
+ * the PLT into a register at the start of the function, which reduces code
+ * size and frees up a register for general use.
+ *
+ * As a general rule, this should be used for any non-exported symbol
+ * (including virtual method implementations).  NS_IMETHOD uses this by
+ * default; if you need to have your NS_IMETHOD functions exported, you can
+ * wrap your class as follows:
+ *
+ * #undef  IMETHOD_VISIBILITY
+ * #define IMETHOD_VISIBILITY NS_VISIBILITY_DEFAULT
+ *
+ * class Foo {
+ * ...
+ * };
+ *
+ * #undef  IMETHOD_VISIBILITY
+ * #define IMETHOD_VISIBILITY NS_VISIBILITY_HIDDEN
+ *
+ * Don't forget to change the visibility back to hidden before the end
+ * of a header!
+ *
+ * Other examples:
+ *
+ * NS_HIDDEN_(int) someMethod();
+ * SomeCtor() NS_HIDDEN;
+ */
+
+#ifdef HAVE_VISIBILITY_HIDDEN_ATTRIBUTE
+#define NS_VISIBILITY_HIDDEN   __attribute__ ((visibility ("hidden")))
+#else
+#define NS_VISIBILITY_HIDDEN
+#endif
+
+#if defined(HAVE_VISIBILITY_HIDDEN_ATTRIBUTE) && defined(HAVE_VISIBILITY_PRAGMA)
+#define NS_VISIBILITY_DEFAULT __attribute__ ((visibility ("default")))
+#else
+#define NS_VISIBILITY_DEFAULT
+#endif
+
+#define NS_HIDDEN_(type)   NS_VISIBILITY_HIDDEN type
+#define NS_EXTERNAL_VIS_(type) NS_VISIBILITY_DEFAULT type
+
+#define NS_HIDDEN           NS_VISIBILITY_HIDDEN
+#define NS_EXTERNAL_VIS     NS_VISIBILITY_DEFAULT
+
+#undef  IMETHOD_VISIBILITY
+#define IMETHOD_VISIBILITY  NS_VISIBILITY_HIDDEN
+
+/**
+ * Mark a function as using a potentially non-standard function calling
+ * convention.  This can be used on functions that are called very
+ * frequently, to reduce the overhead of the function call.  It is still worth
+ * using the macro for C++ functions which take no parameters since it allows
+ * passing |this| in a register.
+ *
+ *  - Do not use this on any scriptable interface method since xptcall won't be
+ *    aware of the different calling convention.
+ *  - This must appear on the declaration, not the definition.
+ *  - Adding this to a public function _will_ break binary compatibility.
+ *  - This may be used on virtual functions but you must ensure it is applied
+ *    to all implementations - the compiler will _not_ warn but it will crash.
+ *  - This has no effect for inline functions or functions which take a
+ *    variable number of arguments.
+ *
+ * Examples: int NS_FASTCALL func1(char *foo);
+ *           NS_HIDDEN_(int) NS_FASTCALL func2(char *foo);
+ */
+
+#if defined(__i386__) && defined(__GNUC__) && (__GNUC__ >= 3) && !defined(XP_OS2)
+#define NS_FASTCALL __attribute__ ((regparm (3), stdcall))
+#else
+#define NS_FASTCALL
+#endif
+
+/*
+ * NS_DEFCALL undoes the effect of a global regparm/stdcall setting
+ * so that xptcall works correctly.
+ */
+#if defined(__i386__) && defined(__GNUC__) && (__GNUC__ >= 3) && !defined(XP_OS2)
+#define NS_DEFCALL __attribute__ ((regparm (0), cdecl))
+#else
+#define NS_DEFCALL
+#endif
+
+#ifdef NS_WIN32
+
+#define NS_IMPORT __declspec(dllimport)
+#define NS_IMPORT_(type) type __declspec(dllimport) __stdcall
+#define NS_EXPORT __declspec(dllexport)
+#define NS_EXPORT_(type) type __declspec(dllexport) __stdcall
+#define NS_IMETHOD_(type) virtual type __stdcall
+#define NS_IMETHODIMP_(type) type __stdcall
+#define NS_METHOD_(type) type __stdcall
+#define NS_CALLBACK_(_type, _name) _type (__stdcall * _name)
+#define NS_STDCALL __stdcall
+
+/*
+  These are needed to mark static members in exported classes, due to
+  gcc bug XXX insert bug# here.
+ */
+
+#define NS_EXPORT_STATIC_MEMBER_(type) type
+#define NS_IMPORT_STATIC_MEMBER_(type) type
+
+#else
+
+#define NS_IMPORT NS_EXTERNAL_VIS
+#define NS_IMPORT_(type) NS_EXTERNAL_VIS_(type)
+#define NS_EXPORT NS_EXTERNAL_VIS
+#define NS_EXPORT_(type) NS_EXTERNAL_VIS_(type)
+#define NS_IMETHOD_(type) virtual IMETHOD_VISIBILITY type NS_DEFCALL
+#define NS_IMETHODIMP_(type) type
+#define NS_METHOD_(type) type
+#define NS_CALLBACK_(_type, _name) _type (* _name)
+#define NS_STDCALL
+#define NS_EXPORT_STATIC_MEMBER_(type) NS_EXTERNAL_VIS_(type)
+#define NS_IMPORT_STATIC_MEMBER_(type) NS_EXTERNAL_VIS_(type)
+
+#endif
+
+/**
+ * Macro for creating typedefs for pointer-to-member types which are
+ * declared with stdcall.  It is important to use this for any type which is
+ * declared as stdcall (i.e. NS_IMETHOD).  For example, instead of writing:
+ *
+ *  typedef nsresult (nsIFoo::*someType)(nsISupports* arg);
+ *
+ *  you should write:
+ *
+ *  typedef
+ *  NS_STDCALL_FUNCPROTO(nsresult, someType, nsIFoo, typeFunc, (nsISupports*));
+ *
+ *  where nsIFoo::typeFunc is any method declared as
+ *  NS_IMETHOD typeFunc(nsISupports*);
+ *
+ *  XXX this can be simplified to always use the non-typeof implementation
+ *  when http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11893 is fixed.
+ */
+
+#ifdef __GNUC__
+#define NS_STDCALL_FUNCPROTO(ret, name, class, func, args) \
+  typeof(&class::func) name
+#else
+#define NS_STDCALL_FUNCPROTO(ret, name, class, func, args) \
+  ret (NS_STDCALL class::*name) args
+#endif
+
+/**
+ * Generic API modifiers which return the standard XPCOM nsresult type
+ */
+#define NS_IMETHOD          NS_IMETHOD_(nsresult)
+#define NS_IMETHODIMP       NS_IMETHODIMP_(nsresult)
+#define NS_METHOD           NS_METHOD_(nsresult)
+#define NS_CALLBACK(_name)  NS_CALLBACK_(nsresult, _name)
+
+/**
+ * Import/Export macros for XPCOM APIs
+ */
+
+#ifdef _IMPL_NS_COM
+#define NS_COM NS_EXPORT
+#elif  _IMPL_NS_COM_OFF
+#define NS_COM
+#elif  XPCOM_GLUE
+#define NS_COM
+#else
+#define NS_COM NS_IMPORT
+#endif
+
+#ifdef MOZILLA_INTERNAL_API
+#  define NS_COM_GLUE NS_COM
+   /*
+     The frozen string API has different definitions of nsAC?String
+     classes than the internal API. On systems that explicitly declare
+     dllexport symbols this is not a problem, but on ELF systems
+     internal symbols can accidentally "shine through"; we rename the
+     internal classes to avoid symbol conflicts.
+   */
+#  define nsAString nsAString_internal
+#  define nsACString nsACString_internal
+#else
+#  define NS_COM_GLUE
+#endif
+
+
+/**
+ * NS_NO_VTABLE is emitted by xpidl in interface declarations whenever
+ * xpidl can determine that the interface can't contain a constructor.
+ * This results in some space savings and possible runtime savings -
+ * see bug 49416.  We undefine it first, as xpidl-generated headers
+ * define it for IDL uses that don't include this file.
+ */
+#ifdef NS_NO_VTABLE
+#undef NS_NO_VTABLE
+#endif
+#if defined(_MSC_VER) && _MSC_VER >= 1100
+#define NS_NO_VTABLE __declspec(novtable)
+#else
+#define NS_NO_VTABLE
+#endif
+
+
+/**
+ * Generic XPCOM result data type
+ */
+typedef PRUint32 nsresult;
+
+/**
+ * The preferred symbol for null.
+ */
+#define nsnull 0
+
+#include "nsError.h"
+
+/* ------------------------------------------------------------------------ */
+/* Casting macros for hiding C++ features from older compilers */
+
+  /*
+    All our compiler support template specialization, but not all support the
+    |template <>| notation.  The compiler that don't understand this notation
+    just omit it for specialization.
+
+    Need to add an autoconf test for this.
+  */
+
+  /* under Metrowerks (Mac), we don't have autoconf yet */
+#ifdef __MWERKS__
+  #define HAVE_CPP_PARTIAL_SPECIALIZATION
+  #define HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
+
+  #define HAVE_CPP_ACCESS_CHANGING_USING
+  #define HAVE_CPP_AMBIGUITY_RESOLVING_USING
+  #define HAVE_CPP_EXPLICIT
+  #define HAVE_CPP_TYPENAME
+  #define HAVE_CPP_BOOL
+  #define HAVE_CPP_NAMESPACE_STD
+  #define HAVE_CPP_UNAMBIGUOUS_STD_NOTEQUAL
+  #define HAVE_CPP_2BYTE_WCHAR_T
+#endif
+
+  /* under VC++ (Windows), we don't have autoconf yet */
+#if defined(_MSC_VER) && (_MSC_VER>=1100)
+  /* VC++ 5.0 and greater implement template specialization, 4.2 is unknown */
+  #define HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
+
+  #define HAVE_CPP_EXPLICIT
+  #define HAVE_CPP_TYPENAME
+  #define HAVE_CPP_ACCESS_CHANGING_USING
+
+  #if (_MSC_VER==1100)
+      /* VC++5.0 has an internal compiler error (sometimes) without this */
+    #undef HAVE_CPP_ACCESS_CHANGING_USING
+  #endif
+
+  #define HAVE_CPP_NAMESPACE_STD
+  #define HAVE_CPP_UNAMBIGUOUS_STD_NOTEQUAL
+  #define HAVE_CPP_2BYTE_WCHAR_T
+#endif
+
+#ifndef __PRUNICHAR__
+#define __PRUNICHAR__
+  /* For now, don't use wchar_t on Unix because it breaks the Netscape
+   * commercial build.  When this is fixed there will be no need for the
+   * |NS_REINTERPRET_CAST| in nsLiteralString.h either.
+   */
+  #if defined(HAVE_CPP_2BYTE_WCHAR_T) && defined(NS_WIN32)
+    typedef wchar_t PRUnichar;
+  #else
+    typedef PRUint16 PRUnichar;
+  #endif
+#endif
+
+  /*
+    If the compiler doesn't support |explicit|, we'll just make it go away, trusting
+    that the builds under compilers that do have it will keep us on the straight and narrow.
+  */
+#ifndef HAVE_CPP_EXPLICIT
+  #define explicit
+#endif
+
+#ifndef HAVE_CPP_TYPENAME
+  #define typename
+#endif
+
+#ifdef HAVE_CPP_MODERN_SPECIALIZE_TEMPLATE_SYNTAX
+  #define NS_SPECIALIZE_TEMPLATE  template <>
+#else
+  #define NS_SPECIALIZE_TEMPLATE
+#endif
+
+/* unix and beos now determine this automatically */
+#if ! defined XP_UNIX && ! defined XP_BEOS && !defined(XP_OS2)
+#ifndef HAVE_CPP_NEW_CASTS
+#define HAVE_CPP_NEW_CASTS 1 /* we'll be optimistic. */
+#endif
+#endif
+
+#if defined(HAVE_CPP_NEW_CASTS)
+#define NS_STATIC_CAST(__type, __ptr)      static_cast< __type >(__ptr)
+#define NS_CONST_CAST(__type, __ptr)       const_cast< __type >(__ptr)
+
+#define NS_REINTERPRET_POINTER_CAST(__type, __ptr)    reinterpret_cast< __type >(__ptr)
+#define NS_REINTERPRET_NONPOINTER_CAST(__type, __obj) reinterpret_cast< __type >(__obj)
+#define NS_REINTERPRET_CAST(__type, __expr)           reinterpret_cast< __type >(__expr)
+
+#else
+#define NS_STATIC_CAST(__type, __ptr)      ((__type)(__ptr))
+#define NS_CONST_CAST(__type, __ptr)       ((__type)(__ptr))
+
+#define NS_REINTERPRET_POINTER_CAST(__type, __ptr)     ((__type)((void*)(__ptr)))
+#define NS_REINTERPRET_NONPOINTER_CAST(__type, __obj)  ((__type)(__obj))
+
+  /* Note: the following is only appropriate for pointers. */
+#define NS_REINTERPRET_CAST(__type, __expr)            NS_REINTERPRET_POINTER_CAST(__type, __expr)
+  /*
+    Why cast to a |void*| first?  Well, when old-style casting from
+    a pointer to a base to a pointer to a derived class, the cast will be
+    ambiguous if the source pointer type appears multiple times in the
+    destination, e.g.,
+    
+      class Base {};
+      class Derived : public Base, public Base {};
+      
+      void foo( Base* b )
+        {
+          ((Derived*)b)->some_derived_member ... // Error: Ambiguous, expand from which |Base|?
+        }
+
+    an old-style cast (like |static_cast|) will change the pointer, but
+    here, doesn't know how.  The cast to |void*| prevents it from thinking
+    it needs to expand the original pointer.
+
+    The cost is, |NS_REINTERPRET_CAST| is no longer appropriate for non-pointer
+    conversions.  Also, mis-applying |NS_REINTERPRET_CAST| to cast |this| to something
+    will still expand the pointer to the outer object in standards complying compilers.
+  */
+
+  /*
+    No sense in making an NS_DYNAMIC_CAST() macro: you can't duplicate
+    the semantics. So if you want to dynamic_cast, then just use it
+    "straight", no macro.
+  */
+#endif
+ 
+/* 
+ * Use these macros to do 64bit safe pointer conversions.
+ */
+
+#define NS_PTR_TO_INT32(x)  ((PRInt32)  (PRWord) (x))
+#define NS_PTR_TO_UINT32(x) ((PRUint32) (PRWord) (x))
+#define NS_INT32_TO_PTR(x)  ((void *)   (PRWord) (x))
+
+/*
+ * Use NS_STRINGIFY to form a string literal from the value of a macro.
+ */
+#define NS_STRINGIFY_HELPER(x_) #x_
+#define NS_STRINGIFY(x_) NS_STRINGIFY_HELPER(x_)
+
+/*
+ * These macros allow you to give a hint to the compiler about branch
+ * probability so that it can better optimize.  Use them like this:
+ *
+ *  if (NS_LIKELY(v == 1)) {
+ *    ... expected code path ...
+ *  }
+ *
+ *  if (NS_UNLIKELY(v == 0)) {
+ *    ... non-expected code path ...
+ *  }
+ *
+ */
+
+#if defined(__GNUC__) && (__GNUC__ > 2)
+#define NS_LIKELY(x)    (__builtin_expect((x), 1))
+#define NS_UNLIKELY(x)  (__builtin_expect((x), 0))
+#else
+#define NS_LIKELY(x)    (x)
+#define NS_UNLIKELY(x)  (x)
+#endif
+
+#endif /* nscore_h___ */