gcc/ada/libgnarl/g-boubuf.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                  G N A T . B O U N D E D _ B U F F E R S                 --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --                     Copyright (C) 2003-2018, AdaCore                     --
  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 -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com).   --
  28 --                                                                          --
  29 ------------------------------------------------------------------------------
  30
  31 package body GNAT.Bounded_Buffers is
  32
  33    --------------------
  34    -- Bounded_Buffer --
  35    --------------------
  36
  37    protected body Bounded_Buffer is
  38
  39       ------------
  40       -- Insert --
  41       ------------
  42
  43       entry Insert (Item : Element) when Count /= Capacity is
  44       begin
  45          Values (Next_In) := Item;
  46          Next_In := (Next_In mod Capacity) + 1;
  47          Count := Count + 1;
  48       end Insert;
  49
  50       ------------
  51       -- Remove --
  52       ------------
  53
  54       entry Remove (Item : out Element) when Count > 0 is
  55       begin
  56          Item := Values (Next_Out);
  57          Next_Out := (Next_Out mod Capacity) + 1;
  58          Count := Count - 1;
  59       end Remove;
  60
  61       -----------
  62       -- Empty --
  63       -----------
  64
  65       function Empty return Boolean is
  66       begin
  67          return Count = 0;
  68       end Empty;
  69
  70       ----------
  71       -- Full --
  72       ----------
  73
  74       function Full return Boolean is
  75       begin
  76          return Count = Capacity;
  77       end Full;
  78
  79       ------------
  80       -- Extent --
  81       ------------
  82
  83       function Extent return Natural is
  84       begin
  85          return Count;
  86       end Extent;
  87
  88    end Bounded_Buffer;
  89
  90 end GNAT.Bounded_Buffers;