------------------------------------------------------------------------------ -- -- -- GNAT RUN-TIME COMPONENTS -- -- -- -- S Y S T E M . M M A P . O S _ I N T E R F A C E -- -- -- -- S p e c -- -- -- -- Copyright (C) 2007-2018, AdaCore -- -- -- -- This library 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 3, or (at your option) any later -- -- version. This library is distributed in the hope that it will be useful, -- -- but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHAN- -- -- TABILITY or FITNESS FOR A PARTICULAR PURPOSE. -- -- -- -- As a special exception under Section 7 of GPL version 3, you are granted -- -- additional permissions described in the GCC Runtime Library Exception, -- -- version 3.1, as published by the Free Software Foundation. -- -- -- -- You should have received a copy of the GNU General Public License and -- -- a copy of the GCC Runtime Library Exception along with this program; -- -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see -- -- . -- -- -- -- GNAT was originally developed by the GNAT team at New York University. -- -- Extensive contributions were provided by Ada Core Technologies Inc. -- -- -- ------------------------------------------------------------------------------ with System.OS_Lib; -- OS pecularities abstraction package for Unix systems. package System.Mmap.OS_Interface is type System_File is record Fd : System.OS_Lib.File_Descriptor; Mapped : Boolean; -- Whether mapping is requested by the user and available on the system Write : Boolean; -- Whether this file can be written to Length : File_Size; -- Length of the file. Used to know what can be mapped in the file end record; type System_Mapping is record Address : Standard.System.Address; Length : File_Size; end record; Invalid_System_File : constant System_File := (System.OS_Lib.Invalid_FD, False, False, 0); Invalid_System_Mapping : constant System_Mapping := (Standard.System.Null_Address, 0); function Open_Read (Filename : String; Use_Mmap_If_Available : Boolean := True) return System_File; -- Open a file for reading and return the corresponding System_File. Return -- Invalid_System_File if unsuccessful. function Open_Write (Filename : String; Use_Mmap_If_Available : Boolean := True) return System_File; -- Likewise for writing to a file procedure Close (File : in out System_File); -- Close a system file function Read_From_Disk (File : System_File; Offset, Length : File_Size) return System.Strings.String_Access; -- Read a fragment of a file. It is up to the caller to free the result -- when done with it. procedure Write_To_Disk (File : System_File; Offset, Length : File_Size; Buffer : System.Strings.String_Access); -- Write some content to a fragment of a file procedure Create_Mapping (File : System_File; Offset, Length : in out File_Size; Mutable : Boolean; Mapping : out System_Mapping); -- Create a memory mapping for the given File, for the area starting at -- Offset and containing Length bytes. Store it to Mapping. -- Note that Offset and Length may be modified according to the system -- needs (for boudaries, for instance). The caller must cope with actually -- wider mapped areas. procedure Dispose_Mapping (Mapping : in out System_Mapping); -- Unmap a previously-created mapping function Get_Page_Size return File_Size; -- Return the number of bytes in a system page. end System.Mmap.OS_Interface;