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------------------------------------------------------------------------------
-- --
-- GNAT COMPILER COMPONENTS --
-- --
-- I N T E R F A C E S . C _ S T R E A M S --
-- --
-- B o d y --
-- --
-- Copyright (C) 1996-2022, 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. --
-- --
------------------------------------------------------------------------------
with Ada.Unchecked_Conversion;
package body Interfaces.C_Streams is
use type System.CRTL.size_t;
----------------------------
-- Interfaced C functions --
----------------------------
function C_fread
(buffer : voids;
size : size_t;
count : size_t;
stream : FILEs) return size_t;
pragma Import (C, C_fread, "fread");
function C_fwrite
(buffer : voids;
size : size_t;
count : size_t;
stream : FILEs) return size_t;
pragma Import (C, C_fwrite, "fwrite");
function C_setvbuf
(stream : FILEs;
buffer : chars;
mode : int;
size : size_t) return int;
pragma Import (C, C_setvbuf, "setvbuf");
------------
-- fread --
------------
function fread
(buffer : voids;
size : size_t;
count : size_t;
stream : FILEs) return size_t
is
begin
return C_fread (buffer, size, count, stream);
end fread;
------------
-- fread --
------------
-- The following declarations should really be nested within fread, but
-- limitations in front end inlining make this undesirable right now ???
type Byte_Buffer is array (0 .. size_t'Last / 2 - 1) of Unsigned_8;
-- This should really be 0 .. size_t'last, but there is a problem
-- in gigi in handling such types (introduced in GCC 3 Sep 2001)
-- since the size in bytes of this array overflows ???
type Acc_Bytes is access all Byte_Buffer;
function To_Acc_Bytes is new Ada.Unchecked_Conversion (voids, Acc_Bytes);
function fread
(buffer : voids;
index : size_t;
size : size_t;
count : size_t;
stream : FILEs) return size_t
is
begin
return C_fread
(To_Acc_Bytes (buffer) (index * size)'Address, size, count, stream);
end fread;
------------
-- fwrite --
------------
function fwrite
(buffer : voids;
size : size_t;
count : size_t;
stream : FILEs) return size_t
is
begin
return C_fwrite (buffer, size, count, stream);
end fwrite;
-------------
-- setvbuf --
-------------
function setvbuf
(stream : FILEs;
buffer : chars;
mode : int;
size : size_t) return int
is
begin
return C_setvbuf (stream, buffer, mode, size);
end setvbuf;
end Interfaces.C_Streams;