File : posix-shared_memory_objects.adb
------------------------------------------------------------------------------
-- --
-- FLORIST (FSU Implementation of POSIX.5) COMPONENTS --
-- --
-- P O S I X . S H A R E D _ M E M O R Y _ O B J E C T S --
-- --
-- B o d y --
-- --
-- --
-- Copyright (c) 1996, 1997 Florida State University (FSU), --
-- All Rights Reserved. --
-- --
-- This file is a component of FLORIST, an implementation of an Ada API --
-- for the POSIX OS services, for use with the GNAT Ada compiler and --
-- the FSU Gnu Ada Runtime Library (GNARL). The interface is intended --
-- to be close to that specified in IEEE STD 1003.5: 1990 and IEEE STD --
-- 1003.5b: 1996. --
-- --
-- FLORIST is free software; you can redistribute it and/or modify it --
-- under terms of the GNU General Public License as published by the --
-- Free Software Foundation; either version 2, or (at your option) any --
-- later version. FLORIST is distributed in the hope that it will be --
-- useful, but WITHOUT ANY WARRANTY; without even the implied warranty --
-- of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU --
-- General Public License for more details. You should have received a --
-- copy of the GNU General Public License distributed with GNARL; see --
-- file COPYING. If not, write to the Free Software Foundation, 59 --
-- Temple Place - Suite 330, Boston, MA 02111-1307, USA. --
-- --
-- As a special exception, if other files instantiate generics from this --
-- unit, or you link this unit with other files to produce an executable, --
-- this unit does not by itself cause the resulting executable to be --
-- covered by the GNU General Public License. This exception does not --
-- however invalidate any other reasons why the executable file might be --
-- covered by the GNU Public License. --
-- --
------------------------------------------------------------------------------
-- [$Revision: 1.1.1.1 $]
with POSIX.C,
POSIX.IO,
POSIX.Implementation,
POSIX.Permissions.Implementation,
Unchecked_Conversion;
package body POSIX.Shared_Memory_Objects is
use POSIX.C;
use POSIX.Implementation;
use POSIX.Permissions.Implementation;
function To_int is new Unchecked_Conversion (Bits, int);
C_File_Mode : constant array (POSIX.IO.File_Mode) of Bits :=
(POSIX.IO.Read_Only => O_RDONLY,
POSIX.IO.Write_Only => O_WRONLY,
POSIX.IO.Read_Write => O_RDWR);
--------------------------
-- Open_Shared_Memory --
--------------------------
function shm_open
(name : char_ptr;
oflag : int;
mode : mode_t) return int;
pragma Import (C, shm_open, shm_open_LINKNAME);
function Open_Shared_Memory
(Name : POSIX.POSIX_String;
Mode : POSIX.IO.File_Mode;
Options : POSIX.IO.Open_Option_Set := -- POSIX.IO.Empty_Set;
POSIX.IO.Open_Option_Set (POSIX.IO.Empty_Set);
-- Conversion is only to work around a GNAT3.09 problem.
Masked_Signals : POSIX.Signal_Masking := POSIX.RTS_Signals)
return POSIX.IO.File_Descriptor is
Old_Mask : aliased Signal_Mask;
Name_With_NUL : POSIX_String := Name & NUL;
Result : POSIX.IO.File_Descriptor;
begin
Mask_Signals (Masked_Signals, Old_Mask'Unchecked_Access);
Result := POSIX.IO.File_Descriptor (Check (shm_open
(Name_With_NUL (Name_With_NUL'First)'Unchecked_Access,
To_int (Option_Set (Options).Option or C_File_Mode (Mode)),
0)));
Check_NNeg_And_Restore_Signals
(int (Result), Masked_Signals, Old_Mask'Unchecked_Access);
return Result;
end Open_Shared_Memory;
------------------------------------
-- Open_Or_Create_Shared_Memory --
------------------------------------
function Open_Or_Create_Shared_Memory
(Name : POSIX.POSIX_String;
Mode : POSIX.IO.File_Mode;
Permissions : POSIX.Permissions.Permission_Set;
Options : POSIX.IO.Open_Option_Set := -- POSIX.IO.Empty_Set;
POSIX.IO.Open_Option_Set (POSIX.IO.Empty_Set);
-- Conversion is only to work around a GNAT3.09 problem.
Masked_Signals : POSIX.Signal_Masking := POSIX.RTS_Signals)
return POSIX.IO.File_Descriptor is
Old_Mask : aliased Signal_Mask;
Name_With_NUL : POSIX_String := Name & NUL;
Result : POSIX.IO.File_Descriptor;
begin
Mask_Signals (Masked_Signals, Old_Mask'Unchecked_Access);
Result := POSIX.IO.File_Descriptor (Check (shm_open
(Name_With_NUL (Name_With_NUL'First)'Unchecked_Access,
To_int (Option_Set (Options).Option or C_File_Mode (Mode) or O_CREAT),
Form_C_Permission (Permissions))));
Check_NNeg_And_Restore_Signals
(int (Result), Masked_Signals, Old_Mask'Unchecked_Access);
return Result;
end Open_Or_Create_Shared_Memory;
----------------------------
-- Unlink_Shared_Memory --
----------------------------
procedure Unlink_Shared_Memory
(Name : in POSIX.POSIX_String) is
Name_With_NUL : POSIX_String := Name & NUL;
function shm_unlink (name : char_ptr) return int;
pragma Import (C, shm_unlink, shm_unlink_LINKNAME);
begin
Check (shm_unlink
(Name_With_NUL (Name_With_NUL'First)'Unchecked_Access));
end Unlink_Shared_Memory;
end POSIX.Shared_Memory_Objects;