gcc/ada/a-coboho.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT LIBRARY COMPONENTS                          --
   4 --                                                                          --
   5 --       A D A . C O N T A I N E R S . B O U N D E D _ H O L D E R S        --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --            Copyright (C) 2014, Free Software Foundation, Inc.            --
  10 --                                                                          --
  11 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  12 -- terms of the  GNU General Public License as published  by the Free Soft- --
  13 -- ware  Foundation;  either version 3,  or (at your option) any later ver- --
  14 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  15 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  16 -- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
  17 --                                                                          --
  18 -- As a special exception under Section 7 of GPL version 3, you are granted --
  19 -- additional permissions described in the GCC Runtime Library Exception,   --
  20 -- version 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
  28 with Unchecked_Conversion;
  29 with Ada.Assertions; use Ada.Assertions;
  30
  31 package body Ada.Containers.Bounded_Holders is
  32
  33    pragma Annotate (CodePeer, Skip_Analysis);
  34
  35    function Size_In_Storage_Elements (Element : Element_Type) return Natural is
  36      (Element'Size / System.Storage_Unit)
  37        with Pre =>
  38        (Element'Size mod System.Storage_Unit = 0 or else
  39           raise Assertion_Error with "Size must be a multiple of Storage_Unit")
  40        and then
  41          (Element'Size / System.Storage_Unit <= Max_Size_In_Storage_Elements
  42             or else raise Assertion_Error with "Size is too big");
  43    --  This returns the size of Element in storage units. It raises an
  44    --  exception if the size is not a multiple of Storage_Unit, or if the size
  45    --  is too big.
  46
  47    function Cast is new
  48      Unchecked_Conversion (System.Address, Element_Access);
  49
  50    ---------
  51    -- "=" --
  52    ---------
  53
  54    function "=" (Left, Right : Holder) return Boolean is
  55    begin
  56       return Get (Left) = Get (Right);
  57    end "=";
  58
  59    -------------
  60    -- Element --
  61    -------------
  62
  63    function Get (Container : Holder) return Element_Type is
  64    begin
  65       return Cast (Container'Address).all;
  66    end Get;
  67
  68    ---------------------
  69    -- Replace_Element --
  70    ---------------------
  71
  72    procedure Set (Container : in out Holder; New_Item  : Element_Type) is
  73       Storage : Storage_Array
  74         (1 .. Size_In_Storage_Elements (New_Item)) with
  75           Address => New_Item'Address;
  76    begin
  77       Container.Data (Storage'Range) := Storage;
  78    end Set;
  79
  80    ---------------
  81    -- To_Holder --
  82    ---------------
  83
  84    function To_Holder (New_Item : Element_Type) return Holder is
  85    begin
  86       return Result : Holder do
  87          Set (Result, New_Item);
  88       end return;
  89    end To_Holder;
  90
  91 end Ada.Containers.Bounded_Holders;