libstdc++
new
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00001 // The -*- C++ -*- dynamic memory management header.
00002 
00003 // Copyright (C) 1994-2013 Free Software Foundation, Inc.
00004 
00005 // This file is part of GCC.
00006 //
00007 // GCC is free software; you can redistribute it and/or modify
00008 // it under the terms of the GNU General Public License as published by
00009 // the Free Software Foundation; either version 3, or (at your option)
00010 // any later version.
00011 // 
00012 // GCC is distributed in the hope that it will be useful,
00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00015 // GNU General Public License for more details.
00016 // 
00017 // Under Section 7 of GPL version 3, you are granted additional
00018 // permissions described in the GCC Runtime Library Exception, version
00019 // 3.1, as published by the Free Software Foundation.
00020 
00021 // You should have received a copy of the GNU General Public License and
00022 // a copy of the GCC Runtime Library Exception along with this program;
00023 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00024 // <http://www.gnu.org/licenses/>.
00025 
00026 /** @file new
00027  *  This is a Standard C++ Library header.
00028  *
00029  *  The header @c new defines several functions to manage dynamic memory and
00030  *  handling memory allocation errors; see
00031  *  http://gcc.gnu.org/onlinedocs/libstdc++/18_support/howto.html#4 for more.
00032  */
00033 
00034 #ifndef _NEW
00035 #define _NEW
00036 
00037 #pragma GCC system_header
00038 
00039 #include <bits/c++config.h>
00040 #include <exception>
00041 
00042 #pragma GCC visibility push(default)
00043 
00044 extern "C++" {
00045 
00046 namespace std 
00047 {
00048   /**
00049    *  @brief  Exception possibly thrown by @c new.
00050    *  @ingroup exceptions
00051    *
00052    *  @c bad_alloc (or classes derived from it) is used to report allocation
00053    *  errors from the throwing forms of @c new.  */
00054   class bad_alloc : public exception 
00055   {
00056   public:
00057     bad_alloc() throw() { }
00058 
00059     // This declaration is not useless:
00060     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
00061     virtual ~bad_alloc() throw();
00062 
00063     // See comment in eh_exception.cc.
00064     virtual const char* what() const throw();
00065   };
00066 
00067   struct nothrow_t { };
00068 
00069   extern const nothrow_t nothrow;
00070 
00071   /** If you write your own error handler to be called by @c new, it must
00072    *  be of this type.  */
00073   typedef void (*new_handler)();
00074 
00075   /// Takes a replacement handler as the argument, returns the
00076   /// previous handler.
00077   new_handler set_new_handler(new_handler) throw();
00078 } // namespace std
00079 
00080 //@{
00081 /** These are replaceable signatures:
00082  *  - normal single new and delete (no arguments, throw @c bad_alloc on error)
00083  *  - normal array new and delete (same)
00084  *  - @c nothrow single new and delete (take a @c nothrow argument, return
00085  *    @c NULL on error)
00086  *  - @c nothrow array new and delete (same)
00087  *
00088  *  Placement new and delete signatures (take a memory address argument,
00089  *  does nothing) may not be replaced by a user's program.
00090 */
00091 void* operator new(std::size_t) _GLIBCXX_THROW (std::bad_alloc)
00092   __attribute__((__externally_visible__));
00093 void* operator new[](std::size_t) _GLIBCXX_THROW (std::bad_alloc)
00094   __attribute__((__externally_visible__));
00095 void operator delete(void*) _GLIBCXX_USE_NOEXCEPT
00096   __attribute__((__externally_visible__));
00097 void operator delete[](void*) _GLIBCXX_USE_NOEXCEPT
00098   __attribute__((__externally_visible__));
00099 void* operator new(std::size_t, const std::nothrow_t&) _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 delete(void*, 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 
00108 // Default placement versions of operator new.
00109 inline void* operator new(std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
00110 { return __p; }
00111 inline void* operator new[](std::size_t, void* __p) _GLIBCXX_USE_NOEXCEPT
00112 { return __p; }
00113 
00114 // Default placement versions of operator delete.
00115 inline void operator delete  (void*, void*) _GLIBCXX_USE_NOEXCEPT { }
00116 inline void operator delete[](void*, void*) _GLIBCXX_USE_NOEXCEPT { }
00117 //@}
00118 } // extern "C++"
00119 
00120 #pragma GCC visibility pop
00121 
00122 #endif