| ------------------------------------------------------------------------------ |
| -- -- |
| -- 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) 2007-2021, 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 -- |
| -- <http://www.gnu.org/licenses/>. -- |
| -- -- |
| -- 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; |
