blob: ec7c14ed5937f321b2363907fc3a03d044560a61 [file] [log] [blame]
------------------------------------------------------------------------------
-- --
-- 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) 2007-2022, 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. --
-- --
------------------------------------------------------------------------------
-- OS pecularities abstraction package for Win32 systems.
package System.Mmap.OS_Interface is
-- The Win package contains copy of definition found in recent System.Win32
-- unit provided with the GNAT compiler. The copy is needed to be able to
-- compile this unit with older compilers. Note that this internal Win
-- package can be removed when GNAT 6.1.0 is not supported anymore.
package Win is
subtype PVOID is Standard.System.Address;
type HANDLE is new Interfaces.C.ptrdiff_t;
type WORD is new Interfaces.C.unsigned_short;
type DWORD is new Interfaces.C.unsigned_long;
type LONG is new Interfaces.C.long;
type SIZE_T is new Interfaces.C.size_t;
type BOOL is new Interfaces.C.int;
for BOOL'Size use Interfaces.C.int'Size;
FALSE : constant := 0;
GENERIC_READ : constant := 16#80000000#;
GENERIC_WRITE : constant := 16#40000000#;
OPEN_EXISTING : constant := 3;
type OVERLAPPED is record
Internal : DWORD;
InternalHigh : DWORD;
Offset : DWORD;
OffsetHigh : DWORD;
hEvent : HANDLE;
end record;
type SECURITY_ATTRIBUTES is record
nLength : DWORD;
pSecurityDescriptor : PVOID;
bInheritHandle : BOOL;
end record;
type SYSTEM_INFO is record
dwOemId : DWORD;
dwPageSize : DWORD;
lpMinimumApplicationAddress : PVOID;
lpMaximumApplicationAddress : PVOID;
dwActiveProcessorMask : PVOID;
dwNumberOfProcessors : DWORD;
dwProcessorType : DWORD;
dwAllocationGranularity : DWORD;
wProcessorLevel : WORD;
wProcessorRevision : WORD;
end record;
type LP_SYSTEM_INFO is access all SYSTEM_INFO;
INVALID_HANDLE_VALUE : constant HANDLE := -1;
FILE_BEGIN : constant := 0;
FILE_SHARE_READ : constant := 16#00000001#;
FILE_ATTRIBUTE_NORMAL : constant := 16#00000080#;
FILE_MAP_COPY : constant := 1;
FILE_MAP_READ : constant := 4;
FILE_MAP_WRITE : constant := 2;
PAGE_READONLY : constant := 16#0002#;
PAGE_READWRITE : constant := 16#0004#;
INVALID_FILE_SIZE : constant := 16#FFFFFFFF#;
function CreateFile
(lpFileName : Standard.System.Address;
dwDesiredAccess : DWORD;
dwShareMode : DWORD;
lpSecurityAttributes : access SECURITY_ATTRIBUTES;
dwCreationDisposition : DWORD;
dwFlagsAndAttributes : DWORD;
hTemplateFile : HANDLE) return HANDLE;
pragma Import (Stdcall, CreateFile, "CreateFileW");
function WriteFile
(hFile : HANDLE;
lpBuffer : Standard.System.Address;
nNumberOfBytesToWrite : DWORD;
lpNumberOfBytesWritten : access DWORD;
lpOverlapped : access OVERLAPPED) return BOOL;
pragma Import (Stdcall, WriteFile, "WriteFile");
function ReadFile
(hFile : HANDLE;
lpBuffer : Standard.System.Address;
nNumberOfBytesToRead : DWORD;
lpNumberOfBytesRead : access DWORD;
lpOverlapped : access OVERLAPPED) return BOOL;
pragma Import (Stdcall, ReadFile, "ReadFile");
function CloseHandle (hObject : HANDLE) return BOOL;
pragma Import (Stdcall, CloseHandle, "CloseHandle");
function GetFileSize
(hFile : HANDLE; lpFileSizeHigh : access DWORD) return DWORD;
pragma Import (Stdcall, GetFileSize, "GetFileSize");
function SetFilePointer
(hFile : HANDLE;
lDistanceToMove : LONG;
lpDistanceToMoveHigh : access LONG;
dwMoveMethod : DWORD) return DWORD;
pragma Import (Stdcall, SetFilePointer, "SetFilePointer");
function CreateFileMapping
(hFile : HANDLE;
lpSecurityAttributes : access SECURITY_ATTRIBUTES;
flProtect : DWORD;
dwMaximumSizeHigh : DWORD;
dwMaximumSizeLow : DWORD;
lpName : Standard.System.Address) return HANDLE;
pragma Import (Stdcall, CreateFileMapping, "CreateFileMappingW");
function MapViewOfFile
(hFileMappingObject : HANDLE;
dwDesiredAccess : DWORD;
dwFileOffsetHigh : DWORD;
dwFileOffsetLow : DWORD;
dwNumberOfBytesToMap : SIZE_T) return Standard.System.Address;
pragma Import (Stdcall, MapViewOfFile, "MapViewOfFile");
function UnmapViewOfFile
(lpBaseAddress : Standard.System.Address) return BOOL;
pragma Import (Stdcall, UnmapViewOfFile, "UnmapViewOfFile");
procedure GetSystemInfo (lpSystemInfo : LP_SYSTEM_INFO);
pragma Import (Stdcall, GetSystemInfo, "GetSystemInfo");
end Win;
type System_File is record
Handle : Win.HANDLE;
Mapped : Boolean;
-- Whether mapping is requested by the user and available on the system
Mapping_Handle : Win.HANDLE;
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 :=
(Win.INVALID_HANDLE_VALUE, False, Win.INVALID_HANDLE_VALUE, 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;