contrib/gcc-4.4/libstdc++-v3/libsupc++/new_op.cc

   1 // Support routines for the -*- C++ -*- dynamic memory management.
   2
   3 // Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2004, 2009
   4 // Free Software Foundation
   5 //
   6 // This file is part of GCC.
   7 //
   8 // GCC is free software; you can redistribute it and/or modify
   9 // it under the terms of the GNU General Public License as published by
  10 // the Free Software Foundation; either version 3, or (at your option)
  11 // any later version.
  12 //
  13 // GCC is distributed in the hope that it will be useful,
  14 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 // GNU General Public License for more details.
  17 //
  18 // Under Section 7 of GPL version 3, you are granted additional
  19 // permissions described in the GCC Runtime Library Exception, version
  20 // 3.1, as published by the Free Software Foundation.
  21
  22 // You should have received a copy of the GNU General Public License and
  23 // a copy of the GCC Runtime Library Exception along with this program;
  24 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  25 // <http://www.gnu.org/licenses/>.
  26
  27 #include <bits/c++config.h>
  28 #include <cstdlib>
  29 #include <exception_defines.h>
  30 #include "new"
  31
  32 using std::new_handler;
  33 using std::bad_alloc;
  34 #if _GLIBCXX_HOSTED
  35 using std::malloc;
  36 #else
  37 // A freestanding C runtime may not provide "malloc" -- but there is no
  38 // other reasonable way to implement "operator new".
  39 extern "C" void *malloc (std::size_t);
  40 #endif
  41
  42 extern new_handler __new_handler;
  43
  44 _GLIBCXX_WEAK_DEFINITION void *
  45 operator new (std::size_t sz) throw (std::bad_alloc)
  46 {
  47   void *p;
  48
  49   /* malloc (0) is unpredictable; avoid it.  */
  50   if (sz == 0)
  51     sz = 1;
  52   p = (void *) malloc (sz);
  53   while (p == 0)
  54     {
  55       new_handler handler = __new_handler;
  56       if (! handler)
  57 #ifdef __EXCEPTIONS
  58         throw bad_alloc();
  59 #else
  60         std::abort();
  61 #endif
  62       handler ();
  63       p = (void *) malloc (sz);
  64     }
  65
  66   return p;
  67 }