libstdc++
new
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00001 // The -*- C++ -*- dynamic memory management header.
00002 
00003 // Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002,
00004 // 2003, 2004, 2005, 2006, 2007, 2009, 2010, 2011
00005 // Free Software Foundation
00006 
00007 // This file is part of GCC.
00008 //
00009 // GCC is free software; you can redistribute it and/or modify
00010 // it under the terms of the GNU General Public License as published by
00011 // the Free Software Foundation; either version 3, or (at your option)
00012 // any later version.
00013 // 
00014 // GCC is distributed in the hope that it will be useful,
00015 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00016 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00017 // GNU General Public License for more details.
00018 // 
00019 // Under Section 7 of GPL version 3, you are granted additional
00020 // permissions described in the GCC Runtime Library Exception, version
00021 // 3.1, as published by the Free Software Foundation.
00022 
00023 // You should have received a copy of the GNU General Public License and
00024 // a copy of the GCC Runtime Library Exception along with this program;
00025 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00026 // <http://www.gnu.org/licenses/>.
00027 
00028 /** @file new
00029  *  This is a Standard C++ Library header.
00030  *
00031  *  The header @c new defines several functions to manage dynamic memory and
00032  *  handling memory allocation errors; see
00033  *  http://gcc.gnu.org/onlinedocs/libstdc++/18_support/howto.html#4 for more.
00034  */
00035 
00036 #ifndef _NEW
00037 #define _NEW
00038 
00039 #pragma GCC system_header
00040 
00041 #include <bits/c++config.h>
00042 #include <exception>
00043 
00044 #pragma GCC visibility push(default)
00045 
00046 extern "C++" {
00047 
00048 namespace std 
00049 {
00050   /**
00051    *  @brief  Exception possibly thrown by @c new.
00052    *  @ingroup exceptions
00053    *
00054    *  @c bad_alloc (or classes derived from it) is used to report allocation
00055    *  errors from the throwing forms of @c new.  */
00056   class bad_alloc : public exception 
00057   {
00058   public:
00059     bad_alloc() throw() { }
00060 
00061     // This declaration is not useless:
00062     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
00063     virtual ~bad_alloc() throw();
00064 
00065     // See comment in eh_exception.cc.
00066     virtual const char* what() const throw();
00067   };
00068 
00069   struct nothrow_t { };
00070 
00071   extern const nothrow_t nothrow;
00072 
00073   /** If you write your own error handler to be called by @c new, it must
00074    *  be of this type.  */
00075   typedef void (*new_handler)();
00076 
00077   /// Takes a replacement handler as the argument, returns the
00078   /// previous handler.
00079   new_handler set_new_handler(new_handler) throw();
00080 } // namespace std
00081 
00082 //@{
00083 /** These are replaceable signatures:
00084  *  - normal single new and delete (no arguments, throw @c bad_alloc on error)
00085  *  - normal array new and delete (same)
00086  *  - @c nothrow single new and delete (take a @c nothrow argument, return
00087  *    @c NULL on error)
00088  *  - @c nothrow array new and delete (same)
00089  *
00090  *  Placement new and delete signatures (take a memory address argument,
00091  *  does nothing) may not be replaced by a user's program.
00092 */
00093 void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
00094   __attribute__((__externally_visible__));
00095 void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
00096   __attribute__((__externally_visible__));
00097 void operator delete(void*) _GLIBCXX_USE_NOEXCEPT
00098   __attribute__((__externally_visible__));
00099 void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT
00100   __attribute__((__externally_visible__));
00101 void* operator new(std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
00102   __attribute__((__externally_visible__));
00103 void* operator new[](std::size_t, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
00104   __attribute__((__externally_visible__));
00105 void operator delete(void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
00106   __attribute__((__externally_visible__));
00107 void operator delete[](void*, const std::nothrow_t&) _GLIBCXX_USE_NOEXCEPT
00108   __attribute__((__externally_visible__));
00109 
00110 // Default placement versions of operator new.
00111 inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
00112 { return __p; }
00113 inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
00114 { return __p; }
00115 
00116 // Default placement versions of operator delete.
00117 inline void operator delete  (void*, void*) _GLIBCXX_USE_NOEXCEPT { }
00118 inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { }
00119 //@}
00120 } // extern "C++"
00121 
00122 #pragma GCC visibility pop
00123 
00124 #endif