| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUNTIME COMPONENTS -- |
| -- -- |
| -- S Y S T E M . D I R E C T _ I O -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2003 Free Software Foundation, Inc. -- |
| -- -- |
| -- GNAT is free software; you can redistribute it and/or modify it under -- |
| -- terms of the GNU General Public License as published by the Free Soft- -- |
| -- ware Foundation; either version 2, or (at your option) any later ver- -- |
| -- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- |
| -- OUT 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 GNAT; 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. -- |
| -- -- |
| -- GNAT was originally developed by the GNAT team at New York University. -- |
| -- Extensive contributions were provided by Ada Core Technologies Inc. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| with Ada.IO_Exceptions; use Ada.IO_Exceptions; |
| with Interfaces.C_Streams; use Interfaces.C_Streams; |
| with System; use System; |
| with System.CRTL; |
| with System.File_IO; |
| with System.Soft_Links; |
| with Unchecked_Deallocation; |
| |
| package body System.Direct_IO is |
| |
| package FIO renames System.File_IO; |
| package SSL renames System.Soft_Links; |
| |
| subtype AP is FCB.AFCB_Ptr; |
| use type FCB.Shared_Status_Type; |
| |
| use type System.CRTL.long; |
| use type System.CRTL.size_t; |
| |
| ----------------------- |
| -- Local Subprograms -- |
| ----------------------- |
| |
| procedure Set_Position (File : in File_Type); |
| -- Sets file position pointer according to value of current index |
| |
| ------------------- |
| -- AFCB_Allocate -- |
| ------------------- |
| |
| function AFCB_Allocate (Control_Block : Direct_AFCB) return FCB.AFCB_Ptr is |
| pragma Unreferenced (Control_Block); |
| |
| begin |
| return new Direct_AFCB; |
| end AFCB_Allocate; |
| |
| ---------------- |
| -- AFCB_Close -- |
| ---------------- |
| |
| -- No special processing required for Direct_IO close |
| |
| procedure AFCB_Close (File : access Direct_AFCB) is |
| pragma Unreferenced (File); |
| |
| begin |
| null; |
| end AFCB_Close; |
| |
| --------------- |
| -- AFCB_Free -- |
| --------------- |
| |
| procedure AFCB_Free (File : access Direct_AFCB) is |
| |
| type FCB_Ptr is access all Direct_AFCB; |
| |
| FT : FCB_Ptr := FCB_Ptr (File); |
| |
| procedure Free is new |
| Unchecked_Deallocation (Direct_AFCB, FCB_Ptr); |
| |
| begin |
| Free (FT); |
| end AFCB_Free; |
| |
| ------------ |
| -- Create -- |
| ------------ |
| |
| procedure Create |
| (File : in out File_Type; |
| Mode : in FCB.File_Mode := FCB.Inout_File; |
| Name : in String := ""; |
| Form : in String := "") |
| is |
| Dummy_File_Control_Block : Direct_AFCB; |
| pragma Warnings (Off, Dummy_File_Control_Block); |
| -- Yes, we know this is never assigned a value, only the tag |
| -- is used for dispatching purposes, so that's expected. |
| |
| begin |
| FIO.Open (File_Ptr => AP (File), |
| Dummy_FCB => Dummy_File_Control_Block, |
| Mode => Mode, |
| Name => Name, |
| Form => Form, |
| Amethod => 'D', |
| Creat => True, |
| Text => False); |
| end Create; |
| |
| ----------------- |
| -- End_Of_File -- |
| ----------------- |
| |
| function End_Of_File (File : in File_Type) return Boolean is |
| begin |
| FIO.Check_Read_Status (AP (File)); |
| return Count (File.Index) > Size (File); |
| end End_Of_File; |
| |
| ----------- |
| -- Index -- |
| ----------- |
| |
| function Index (File : in File_Type) return Positive_Count is |
| begin |
| FIO.Check_File_Open (AP (File)); |
| return Count (File.Index); |
| end Index; |
| |
| ---------- |
| -- Open -- |
| ---------- |
| |
| procedure Open |
| (File : in out File_Type; |
| Mode : in FCB.File_Mode; |
| Name : in String; |
| Form : in String := "") |
| is |
| Dummy_File_Control_Block : Direct_AFCB; |
| pragma Warnings (Off, Dummy_File_Control_Block); |
| -- Yes, we know this is never assigned a value, only the tag |
| -- is used for dispatching purposes, so that's expected. |
| |
| begin |
| FIO.Open (File_Ptr => AP (File), |
| Dummy_FCB => Dummy_File_Control_Block, |
| Mode => Mode, |
| Name => Name, |
| Form => Form, |
| Amethod => 'D', |
| Creat => False, |
| Text => False); |
| end Open; |
| |
| ---------- |
| -- Read -- |
| ---------- |
| |
| procedure Read |
| (File : in File_Type; |
| Item : Address; |
| Size : in Interfaces.C_Streams.size_t; |
| From : in Positive_Count) |
| is |
| begin |
| Set_Index (File, From); |
| Read (File, Item, Size); |
| end Read; |
| |
| procedure Read |
| (File : in File_Type; |
| Item : Address; |
| Size : in Interfaces.C_Streams.size_t) |
| is |
| begin |
| FIO.Check_Read_Status (AP (File)); |
| |
| -- If last operation was not a read, or if in file sharing mode, |
| -- then reset the physical pointer of the file to match the index |
| -- We lock out task access over the two operations in this case. |
| |
| if File.Last_Op /= Op_Read |
| or else File.Shared_Status = FCB.Yes |
| then |
| if End_Of_File (File) then |
| raise End_Error; |
| end if; |
| |
| Locked_Processing : begin |
| SSL.Lock_Task.all; |
| Set_Position (File); |
| FIO.Read_Buf (AP (File), Item, Size); |
| SSL.Unlock_Task.all; |
| |
| exception |
| when others => |
| SSL.Unlock_Task.all; |
| raise; |
| end Locked_Processing; |
| |
| else |
| FIO.Read_Buf (AP (File), Item, Size); |
| end if; |
| |
| File.Index := File.Index + 1; |
| |
| -- Set last operation to read, unless we did not read a full record |
| -- (happens with the variant record case) in which case we set the |
| -- last operation as other, to force the file position to be reset |
| -- on the next read. |
| |
| if File.Bytes = Size then |
| File.Last_Op := Op_Read; |
| else |
| File.Last_Op := Op_Other; |
| end if; |
| end Read; |
| |
| -- The following is the required overriding for Stream.Read, which is |
| -- not used, since we do not do Stream operations on Direct_IO files. |
| |
| procedure Read |
| (File : in out Direct_AFCB; |
| Item : out Ada.Streams.Stream_Element_Array; |
| Last : out Ada.Streams.Stream_Element_Offset) |
| is |
| begin |
| raise Program_Error; |
| end Read; |
| |
| ----------- |
| -- Reset -- |
| ----------- |
| |
| procedure Reset (File : in out File_Type; Mode : in FCB.File_Mode) is |
| begin |
| FIO.Reset (AP (File), Mode); |
| File.Index := 1; |
| File.Last_Op := Op_Read; |
| end Reset; |
| |
| procedure Reset (File : in out File_Type) is |
| begin |
| FIO.Reset (AP (File)); |
| File.Index := 1; |
| File.Last_Op := Op_Read; |
| end Reset; |
| |
| --------------- |
| -- Set_Index -- |
| --------------- |
| |
| procedure Set_Index (File : in File_Type; To : in Positive_Count) is |
| begin |
| FIO.Check_File_Open (AP (File)); |
| File.Index := Count (To); |
| File.Last_Op := Op_Other; |
| end Set_Index; |
| |
| ------------------ |
| -- Set_Position -- |
| ------------------ |
| |
| procedure Set_Position (File : in File_Type) is |
| begin |
| if fseek |
| (File.Stream, long (File.Bytes) * |
| long (File.Index - 1), SEEK_SET) /= 0 |
| then |
| raise Use_Error; |
| end if; |
| end Set_Position; |
| |
| ---------- |
| -- Size -- |
| ---------- |
| |
| function Size (File : in File_Type) return Count is |
| begin |
| FIO.Check_File_Open (AP (File)); |
| File.Last_Op := Op_Other; |
| |
| if fseek (File.Stream, 0, SEEK_END) /= 0 then |
| raise Device_Error; |
| end if; |
| |
| return Count (ftell (File.Stream) / long (File.Bytes)); |
| end Size; |
| |
| ----------- |
| -- Write -- |
| ----------- |
| |
| procedure Write |
| (File : File_Type; |
| Item : Address; |
| Size : in Interfaces.C_Streams.size_t; |
| Zeroes : System.Storage_Elements.Storage_Array) |
| |
| is |
| procedure Do_Write; |
| -- Do the actual write |
| |
| procedure Do_Write is |
| begin |
| FIO.Write_Buf (AP (File), Item, Size); |
| |
| -- If we did not write the whole record (happens with the variant |
| -- record case), then fill out the rest of the record with zeroes. |
| -- This is cleaner in any case, and is required for the last |
| -- record, since otherwise the length of the file is wrong. |
| |
| if File.Bytes > Size then |
| FIO.Write_Buf (AP (File), Zeroes'Address, File.Bytes - Size); |
| end if; |
| end Do_Write; |
| |
| -- Start of processing for Write |
| |
| begin |
| FIO.Check_Write_Status (AP (File)); |
| |
| -- If last operation was not a write, or if in file sharing mode, |
| -- then reset the physical pointer of the file to match the index |
| -- We lock out task access over the two operations in this case. |
| |
| if File.Last_Op /= Op_Write |
| or else File.Shared_Status = FCB.Yes |
| then |
| Locked_Processing : begin |
| SSL.Lock_Task.all; |
| Set_Position (File); |
| Do_Write; |
| SSL.Unlock_Task.all; |
| |
| exception |
| when others => |
| SSL.Unlock_Task.all; |
| raise; |
| end Locked_Processing; |
| |
| else |
| Do_Write; |
| end if; |
| |
| File.Index := File.Index + 1; |
| |
| -- Set last operation to write, unless we did not read a full record |
| -- (happens with the variant record case) in which case we set the |
| -- last operation as other, to force the file position to be reset |
| -- on the next write. |
| |
| if File.Bytes = Size then |
| File.Last_Op := Op_Write; |
| else |
| File.Last_Op := Op_Other; |
| end if; |
| end Write; |
| |
| -- The following is the required overriding for Stream.Write, which is |
| -- not used, since we do not do Stream operations on Direct_IO files. |
| |
| procedure Write |
| (File : in out Direct_AFCB; |
| Item : in Ada.Streams.Stream_Element_Array) |
| is |
| begin |
| raise Program_Error; |
| end Write; |
| |
| end System.Direct_IO; |
