| ------------------------------------------------------------------------------ |
| -- -- |
| -- GNAT RUN-TIME COMPONENTS -- |
| -- -- |
| -- A D A . S E Q U E N T I A L _ I O -- |
| -- -- |
| -- B o d y -- |
| -- -- |
| -- Copyright (C) 1992-2022, 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 3, 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. -- |
| -- -- |
| -- 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. -- |
| -- -- |
| ------------------------------------------------------------------------------ |
| |
| -- This is the generic template for Sequential_IO, i.e. the code that gets |
| -- duplicated. We absolutely minimize this code by either calling routines |
| -- in System.File_IO (for common file functions), or in System.Sequential_IO |
| -- (for specialized Sequential_IO functions) |
| |
| with Ada.Unchecked_Conversion; |
| |
| with System; |
| with System.Byte_Swapping; |
| with System.CRTL; |
| with System.File_Control_Block; |
| with System.File_IO; |
| with System.Storage_Elements; |
| |
| with Interfaces.C_Streams; use Interfaces.C_Streams; |
| |
| package body Ada.Sequential_IO is |
| |
| package FIO renames System.File_IO; |
| package FCB renames System.File_Control_Block; |
| package SIO renames System.Sequential_IO; |
| package SSE renames System.Storage_Elements; |
| |
| SU : constant := System.Storage_Unit; |
| |
| subtype AP is FCB.AFCB_Ptr; |
| subtype FP is SIO.File_Type; |
| |
| function To_FCB is new Ada.Unchecked_Conversion (File_Mode, FCB.File_Mode); |
| function To_SIO is new Ada.Unchecked_Conversion (FCB.File_Mode, File_Mode); |
| |
| use type System.Bit_Order; |
| use type System.CRTL.size_t; |
| |
| procedure Byte_Swap (Siz : in out size_t); |
| -- Byte swap Siz |
| |
| --------------- |
| -- Byte_Swap -- |
| --------------- |
| |
| procedure Byte_Swap (Siz : in out size_t) is |
| use System.Byte_Swapping; |
| begin |
| case size_t'Size is |
| when 32 => Siz := size_t (Bswap_32 (U32 (Siz))); |
| when 64 => Siz := size_t (Bswap_64 (U64 (Siz))); |
| when others => raise Program_Error; |
| end case; |
| end Byte_Swap; |
| |
| ----------- |
| -- Close -- |
| ----------- |
| |
| procedure Close (File : in out File_Type) is |
| begin |
| FIO.Close (AP (File)'Unrestricted_Access); |
| end Close; |
| |
| ------------ |
| -- Create -- |
| ------------ |
| |
| procedure Create |
| (File : in out File_Type; |
| Mode : File_Mode := Out_File; |
| Name : String := ""; |
| Form : String := "") |
| is |
| begin |
| SIO.Create (FP (File), To_FCB (Mode), Name, Form); |
| end Create; |
| |
| ------------ |
| -- Delete -- |
| ------------ |
| |
| procedure Delete (File : in out File_Type) is |
| begin |
| FIO.Delete (AP (File)'Unrestricted_Access); |
| end Delete; |
| |
| ----------------- |
| -- End_Of_File -- |
| ----------------- |
| |
| function End_Of_File (File : File_Type) return Boolean is |
| begin |
| return FIO.End_Of_File (AP (File)); |
| end End_Of_File; |
| |
| ----------- |
| -- Flush -- |
| ----------- |
| |
| procedure Flush (File : File_Type) is |
| begin |
| FIO.Flush (AP (File)); |
| end Flush; |
| |
| ---------- |
| -- Form -- |
| ---------- |
| |
| function Form (File : File_Type) return String is |
| begin |
| return FIO.Form (AP (File)); |
| end Form; |
| |
| ------------- |
| -- Is_Open -- |
| ------------- |
| |
| function Is_Open (File : File_Type) return Boolean is |
| begin |
| return FIO.Is_Open (AP (File)); |
| end Is_Open; |
| |
| ---------- |
| -- Mode -- |
| ---------- |
| |
| function Mode (File : File_Type) return File_Mode is |
| begin |
| return To_SIO (FIO.Mode (AP (File))); |
| end Mode; |
| |
| ---------- |
| -- Name -- |
| ---------- |
| |
| function Name (File : File_Type) return String is |
| begin |
| return FIO.Name (AP (File)); |
| end Name; |
| |
| ---------- |
| -- Open -- |
| ---------- |
| |
| procedure Open |
| (File : in out File_Type; |
| Mode : File_Mode; |
| Name : String; |
| Form : String := "") |
| is |
| begin |
| SIO.Open (FP (File), To_FCB (Mode), Name, Form); |
| end Open; |
| |
| ---------- |
| -- Read -- |
| ---------- |
| |
| procedure Read (File : File_Type; Item : out Element_Type) is |
| Siz : constant size_t := (Item'Size + SU - 1) / SU; |
| Rsiz : size_t; |
| |
| begin |
| FIO.Check_Read_Status (AP (File)); |
| |
| -- For non-definite type or type with discriminants, read size and |
| -- raise Program_Error if it is larger than the size of the item. |
| |
| if not Element_Type'Definite |
| or else Element_Type'Has_Discriminants |
| then |
| FIO.Read_Buf |
| (AP (File), Rsiz'Address, size_t'Size / System.Storage_Unit); |
| |
| -- If item read has non-default scalar storage order, then the size |
| -- will have been written with that same order, so byte swap it. |
| |
| if Element_Type'Scalar_Storage_Order /= System.Default_Bit_Order then |
| Byte_Swap (Rsiz); |
| end if; |
| |
| -- For a type with discriminants, we have to read into a temporary |
| -- buffer if Item is constrained, to check that the discriminants |
| -- are correct. |
| |
| if Element_Type'Has_Discriminants and then Item'Constrained then |
| declare |
| RsizS : constant SSE.Storage_Offset := |
| SSE.Storage_Offset (Rsiz - 1); |
| |
| type SA is new SSE.Storage_Array (0 .. RsizS); |
| |
| for SA'Alignment use Standard'Maximum_Alignment; |
| -- We will perform an unchecked conversion of a pointer-to-SA |
| -- into pointer-to-Element_Type. We need to ensure that the |
| -- source is always at least as strictly aligned as the target. |
| |
| type SAP is access all SA; |
| type ItemP is access all Element_Type; |
| |
| pragma Warnings (Off); |
| -- We have to turn warnings off for function To_ItemP, |
| -- because it gets analyzed for all types, including ones |
| -- which can't possibly come this way, and for which the |
| -- size of the access types differs. |
| |
| function To_ItemP is new Ada.Unchecked_Conversion (SAP, ItemP); |
| |
| pragma Warnings (On); |
| |
| Buffer : aliased SA; |
| |
| pragma Unsuppress (Discriminant_Check); |
| |
| begin |
| FIO.Read_Buf (AP (File), Buffer'Address, Rsiz); |
| Item := To_ItemP (Buffer'Access).all; |
| return; |
| end; |
| end if; |
| |
| -- In the case of a non-definite type, make sure the length is OK. |
| -- We can't do this in the variant record case, because the size is |
| -- based on the current discriminant, so may be apparently wrong. |
| |
| if not Element_Type'Has_Discriminants and then Rsiz > Siz then |
| raise Program_Error; |
| end if; |
| |
| FIO.Read_Buf (AP (File), Item'Address, Rsiz); |
| |
| -- For definite type without discriminants, use actual size of item |
| |
| else |
| FIO.Read_Buf (AP (File), Item'Address, Siz); |
| end if; |
| end Read; |
| |
| ----------- |
| -- Reset -- |
| ----------- |
| |
| procedure Reset (File : in out File_Type; Mode : File_Mode) is |
| begin |
| FIO.Reset (AP (File)'Unrestricted_Access, To_FCB (Mode)); |
| end Reset; |
| |
| procedure Reset (File : in out File_Type) is |
| begin |
| FIO.Reset (AP (File)'Unrestricted_Access); |
| end Reset; |
| |
| ----------- |
| -- Write -- |
| ----------- |
| |
| procedure Write (File : File_Type; Item : Element_Type) is |
| Siz : constant size_t := (Item'Size + SU - 1) / SU; |
| -- Size to be written, in native representation |
| |
| Swapped_Siz : size_t := Siz; |
| -- Same, possibly byte swapped to account for Element_Type endianness |
| |
| begin |
| FIO.Check_Write_Status (AP (File)); |
| |
| -- For non-definite types or types with discriminants, write the size |
| |
| if not Element_Type'Definite |
| or else Element_Type'Has_Discriminants |
| then |
| -- If item written has non-default scalar storage order, then the |
| -- size is written with that same order, so byte swap it. |
| |
| if Element_Type'Scalar_Storage_Order /= System.Default_Bit_Order then |
| Byte_Swap (Swapped_Siz); |
| end if; |
| |
| FIO.Write_Buf |
| (AP (File), Swapped_Siz'Address, size_t'Size / System.Storage_Unit); |
| end if; |
| |
| FIO.Write_Buf (AP (File), Item'Address, Siz); |
| end Write; |
| |
| end Ada.Sequential_IO; |
