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Diffstat (limited to 'gcc/ada/s-direio.adb')
| -rw-r--r-- | gcc/ada/s-direio.adb | 377 |
1 files changed, 377 insertions, 0 deletions
diff --git a/gcc/ada/s-direio.adb b/gcc/ada/s-direio.adb new file mode 100644 index 00000000000..1aeb84149a4 --- /dev/null +++ b/gcc/ada/s-direio.adb @@ -0,0 +1,377 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUNTIME COMPONENTS -- +-- -- +-- S Y S T E M . D I R E C T _ I O -- +-- -- +-- B o d y -- +-- -- +-- $Revision: 1.17 $ +-- -- +-- Copyright (C) 1992-1999 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. -- +-- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). -- +-- -- +------------------------------------------------------------------------------ + +with Ada.IO_Exceptions; use Ada.IO_Exceptions; +with Interfaces.C_Streams; use Interfaces.C_Streams; +with System; use System; +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; + + ----------------------- + -- 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 + 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 + 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 + File_Control_Block : Direct_AFCB; + + begin + FIO.Open (File_Ptr => AP (File), + Dummy_FCB => 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 + File_Control_Block : Direct_AFCB; + + begin + FIO.Open (File_Ptr => AP (File), + Dummy_FCB => 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; |