File : a-textio.adb
------------------------------------------------------------------------------
-- --
-- GNAT RUNTIME COMPONENTS --
-- --
5 -- A D A . T E X T _ I O --
-- --
-- B o d y --
-- --
-- $Revision: 1.82 $
10 -- --
-- Copyright (C) 1992-2001 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- --
15 -- 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 --
20 -- 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 --
25 -- 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. --
30 -- --
-- 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). --
-- --
------------------------------------------------------------------------------
35
with Ada.Streams; use Ada.Streams;
with Interfaces.C_Streams; use Interfaces.C_Streams;
with System;
with System.File_IO;
40 with Unchecked_Conversion;
with Unchecked_Deallocation;
pragma Elaborate_All (System.File_IO);
-- Needed because of calls to Chain_File in package body elaboration
45
package body Ada.Text_IO is
package FIO renames System.File_IO;
50 subtype AP is FCB.AFCB_Ptr;
function To_FCB is new Unchecked_Conversion (File_Mode, FCB.File_Mode);
function To_TIO is new Unchecked_Conversion (FCB.File_Mode, File_Mode);
use type FCB.File_Mode;
55
-------------------
-- AFCB_Allocate --
-------------------
60 function AFCB_Allocate (Control_Block : Text_AFCB) return FCB.AFCB_Ptr is
pragma Warnings (Off, Control_Block);
begin
return new Text_AFCB;
65 end AFCB_Allocate;
----------------
-- AFCB_Close --
----------------
70
procedure AFCB_Close (File : access Text_AFCB) is
begin
-- If the file being closed is one of the current files, then close
-- the corresponding current file. It is not clear that this action
75 -- is required (RM A.10.3(23)) but it seems reasonable, and besides
-- ACVC test CE3208A expects this behavior.
if File_Type (File) = Current_In then
Current_In := null;
80 elsif File_Type (File) = Current_Out then
Current_Out := null;
elsif File_Type (File) = Current_Err then
Current_Err := null;
end if;
85
Terminate_Line (File_Type (File));
end AFCB_Close;
---------------
90 -- AFCB_Free --
---------------
procedure AFCB_Free (File : access Text_AFCB) is
type FCB_Ptr is access all Text_AFCB;
95 FT : FCB_Ptr := FCB_Ptr (File);
procedure Free is new Unchecked_Deallocation (Text_AFCB, FCB_Ptr);
begin
100 Free (FT);
end AFCB_Free;
-----------
-- Close --
105 -----------
procedure Close (File : in out File_Type) is
begin
FIO.Close (AP (File));
110 end Close;
---------
-- Col --
---------
115
-- Note: we assume that it is impossible in practice for the column
-- to exceed the value of Count'Last, i.e. no check is required for
-- overflow raising layout error.
120 function Col (File : in File_Type) return Positive_Count is
begin
FIO.Check_File_Open (AP (File));
return File.Col;
end Col;
125
function Col return Positive_Count is
begin
return Col (Current_Out);
end Col;
130
------------
-- Create --
------------
135 procedure Create
(File : in out File_Type;
Mode : in File_Mode := Out_File;
Name : in String := "";
Form : in String := "")
140 is
File_Control_Block : Text_AFCB;
begin
FIO.Open (File_Ptr => AP (File),
145 Dummy_FCB => File_Control_Block,
Mode => To_FCB (Mode),
Name => Name,
Form => Form,
Amethod => 'T',
150 Creat => True,
Text => True);
File.Self := File;
end Create;
155
-------------------
-- Current_Error --
-------------------
160 function Current_Error return File_Type is
begin
return Current_Err;
end Current_Error;
165 function Current_Error return File_Access is
begin
return Current_Err.Self'Access;
end Current_Error;
170 -------------------
-- Current_Input --
-------------------
function Current_Input return File_Type is
175 begin
return Current_In;
end Current_Input;
function Current_Input return File_Access is
180 begin
return Current_In.Self'Access;
end Current_Input;
--------------------
185 -- Current_Output --
--------------------
function Current_Output return File_Type is
begin
190 return Current_Out;
end Current_Output;
function Current_Output return File_Access is
begin
195 return Current_Out.Self'Access;
end Current_Output;
------------
-- Delete --
200 ------------
procedure Delete (File : in out File_Type) is
begin
FIO.Delete (AP (File));
205 end Delete;
-----------------
-- End_Of_File --
-----------------
210
function End_Of_File (File : in File_Type) return Boolean is
ch : int;
begin
215 FIO.Check_Read_Status (AP (File));
if File.Before_LM then
if File.Before_LM_PM then
220 return Nextc (File) = EOF;
end if;
else
ch := Getc (File);
225
if ch = EOF then
return True;
elsif ch /= LM then
230 Ungetc (ch, File);
return False;
else -- ch = LM
File.Before_LM := True;
235 end if;
end if;
-- Here we are just past the line mark with Before_LM set so that we
-- do not have to try to back up past the LM, thus avoiding the need
240 -- to back up more than one character.
ch := Getc (File);
if ch = EOF then
245 return True;
elsif ch = PM and then File.Is_Regular_File then
File.Before_LM_PM := True;
return Nextc (File) = EOF;
250
-- Here if neither EOF nor PM followed end of line
else
Ungetc (ch, File);
255 return False;
end if;
end End_Of_File;
260 function End_Of_File return Boolean is
begin
return End_Of_File (Current_In);
end End_Of_File;
265 -----------------
-- End_Of_Line --
-----------------
function End_Of_Line (File : in File_Type) return Boolean is
270 ch : int;
begin
FIO.Check_Read_Status (AP (File));
275 if File.Before_LM then
return True;
else
ch := Getc (File);
280
if ch = EOF then
return True;
else
285 Ungetc (ch, File);
return (ch = LM);
end if;
end if;
end End_Of_Line;
290
function End_Of_Line return Boolean is
begin
return End_Of_Line (Current_In);
end End_Of_Line;
295
-----------------
-- End_Of_Page --
-----------------
300 function End_Of_Page (File : in File_Type) return Boolean is
ch : int;
begin
FIO.Check_Read_Status (AP (File));
305
if not File.Is_Regular_File then
return False;
elsif File.Before_LM then
310 if File.Before_LM_PM then
return True;
end if;
else
315 ch := Getc (File);
if ch = EOF then
return True;
320 elsif ch /= LM then
Ungetc (ch, File);
return False;
else -- ch = LM
325 File.Before_LM := True;
end if;
end if;
-- Here we are just past the line mark with Before_LM set so that we
330 -- do not have to try to back up past the LM, thus avoiding the need
-- to back up more than one character.
ch := Nextc (File);
335 return ch = PM or else ch = EOF;
end End_Of_Page;
function End_Of_Page return Boolean is
begin
340 return End_Of_Page (Current_In);
end End_Of_Page;
-----------
-- Flush --
345 -----------
procedure Flush (File : in File_Type) is
begin
FIO.Flush (AP (File));
350 end Flush;
procedure Flush is
begin
Flush (Current_Out);
355 end Flush;
----------
-- Form --
----------
360
function Form (File : in File_Type) return String is
begin
return FIO.Form (AP (File));
end Form;
365
---------
-- Get --
---------
370 procedure Get
(File : in File_Type;
Item : out Character)
is
ch : int;
375
begin
FIO.Check_Read_Status (AP (File));
if File.Before_LM then
380 File.Before_LM := False;
File.Col := 1;
if File.Before_LM_PM then
File.Line := 1;
385 File.Page := File.Page + 1;
File.Before_LM_PM := False;
else
File.Line := File.Line + 1;
end if;
390 end if;
loop
ch := Getc (File);
395 if ch = EOF then
raise End_Error;
elsif ch = LM then
File.Line := File.Line + 1;
400 File.Col := 1;
elsif ch = PM and then File.Is_Regular_File then
File.Page := File.Page + 1;
File.Line := 1;
405
else
Item := Character'Val (ch);
File.Col := File.Col + 1;
return;
410 end if;
end loop;
end Get;
procedure Get (Item : out Character) is
415 begin
Get (Current_In, Item);
end Get;
procedure Get
420 (File : in File_Type;
Item : out String)
is
ch : int;
J : Natural;
425
begin
FIO.Check_Read_Status (AP (File));
if File.Before_LM then
430 File.Before_LM := False;
File.Before_LM_PM := False;
File.Col := 1;
if File.Before_LM_PM then
435 File.Line := 1;
File.Page := File.Page + 1;
File.Before_LM_PM := False;
else
440 File.Line := File.Line + 1;
end if;
end if;
J := Item'First;
445 while J <= Item'Last loop
ch := Getc (File);
if ch = EOF then
raise End_Error;
450
elsif ch = LM then
File.Line := File.Line + 1;
File.Col := 1;
455 elsif ch = PM and then File.Is_Regular_File then
File.Page := File.Page + 1;
File.Line := 1;
else
460 Item (J) := Character'Val (ch);
J := J + 1;
File.Col := File.Col + 1;
end if;
end loop;
465 end Get;
procedure Get (Item : out String) is
begin
Get (Current_In, Item);
470 end Get;
-------------------
-- Get_Immediate --
-------------------
475
-- More work required here ???
procedure Get_Immediate
(File : in File_Type;
480 Item : out Character)
is
ch : int;
end_of_file : int;
485 procedure getc_immediate
(stream : FILEs; ch : out int; end_of_file : out int);
pragma Import (C, getc_immediate, "getc_immediate");
begin
490 FIO.Check_Read_Status (AP (File));
if File.Before_LM then
File.Before_LM := False;
File.Before_LM_PM := False;
495 ch := LM;
else
getc_immediate (File.Stream, ch, end_of_file);
500 if ferror (File.Stream) /= 0 then
raise Device_Error;
elsif end_of_file /= 0 then
raise End_Error;
end if;
505 end if;
Item := Character'Val (ch);
end Get_Immediate;
510
procedure Get_Immediate
(Item : out Character)
is
begin
515 Get_Immediate (Current_In, Item);
end Get_Immediate;
procedure Get_Immediate
(File : in File_Type;
520 Item : out Character;
Available : out Boolean)
is
ch : int;
end_of_file : int;
525 avail : int;
procedure getc_immediate_nowait
(stream : FILEs;
ch : out int;
530 end_of_file : out int;
avail : out int);
pragma Import (C, getc_immediate_nowait, "getc_immediate_nowait");
begin
535 FIO.Check_Read_Status (AP (File));
-- If we are logically before an end of line, but physically after it,
-- then we just return the end of line character, no I/O is necessary.
540 if File.Before_LM then
File.Before_LM := False;
File.Before_LM_PM := False;
Available := True;
545 Item := Character'Val (LM);
-- Normal case where a read operation is required
else
550 getc_immediate_nowait (File.Stream, ch, end_of_file, avail);
if ferror (File.Stream) /= 0 then
raise Device_Error;
555 elsif end_of_file /= 0 then
raise End_Error;
elsif avail = 0 then
Available := False;
560 Item := ASCII.NUL;
else
Available := True;
Item := Character'Val (ch);
565 end if;
end if;
end Get_Immediate;
570 procedure Get_Immediate
(Item : out Character;
Available : out Boolean)
is
begin
575 Get_Immediate (Current_In, Item, Available);
end Get_Immediate;
--------------
-- Get_Line --
580 --------------
procedure Get_Line
(File : in File_Type;
Item : out String;
585 Last : out Natural)
is
ch : int;
begin
590 FIO.Check_Read_Status (AP (File));
Last := Item'First - 1;
-- Immediate exit for null string, this is a case in which we do not
-- need to test for end of file and we do not skip a line mark under
595 -- any circumstances.
if Last >= Item'Last then
return;
end if;
600
-- Here we have at least one character, if we are immediately before
-- a line mark, then we will just skip past it storing no characters.
if File.Before_LM then
605 File.Before_LM := False;
File.Before_LM_PM := False;
-- Otherwise we need to read some characters
610 else
ch := Getc (File);
-- If we are at the end of file now, it means we are trying to
-- skip a file terminator and we raise End_Error (RM A.10.7(20))
615
if ch = EOF then
raise End_Error;
end if;
620 -- Loop through characters. Don't bother if we hit a page mark,
-- since in normal files, page marks can only follow line marks
-- in any case and we only promise to treat the page nonsense
-- correctly in the absense of such rogue page marks.
625 loop
-- Exit the loop if read is terminated by encountering line mark
exit when ch = LM;
630 -- Otherwise store the character, note that we know that ch is
-- something other than LM or EOF. It could possibly be a page
-- mark if there is a stray page mark in the middle of a line,
-- but this is not an official page mark in any case, since
-- official page marks can only follow a line mark. The whole
635 -- page business is pretty much nonsense anyway, so we do not
-- want to waste time trying to make sense out of non-standard
-- page marks in the file! This means that the behavior of
-- Get_Line is different from repeated Get of a character, but
-- that's too bad. We only promise that page numbers etc make
640 -- sense if the file is formatted in a standard manner.
-- Note: we do not adjust the column number because it is quicker
-- to adjust it once at the end of the operation than incrementing
-- it each time around the loop.
645
Last := Last + 1;
Item (Last) := Character'Val (ch);
-- All done if the string is full, this is the case in which
650 -- we do not skip the following line mark. We need to adjust
-- the column number in this case.
if Last = Item'Last then
File.Col := File.Col + Count (Item'Length);
655 return;
end if;
-- Otherwise read next character. We also exit from the loop if
-- we read an end of file. This is the case where the last line
660 -- is not terminated with a line mark, and we consider that there
-- is an implied line mark in this case (this is a non-standard
-- file, but it is nice to treat it reasonably).
ch := Getc (File);
665 exit when ch = EOF;
end loop;
end if;
-- We have skipped past, but not stored, a line mark. Skip following
670 -- page mark if one follows, but do not do this for a non-regular
-- file (since otherwise we get annoying wait for an extra character)
File.Line := File.Line + 1;
File.Col := 1;
675
if File.Before_LM_PM then
File.Line := 1;
File.Before_LM_PM := False;
File.Page := File.Page + 1;
680
elsif File.Is_Regular_File then
ch := Getc (File);
if ch = PM and then File.Is_Regular_File then
685 File.Line := 1;
File.Page := File.Page + 1;
else
Ungetc (ch, File);
end if;
690 end if;
end Get_Line;
procedure Get_Line
(Item : out String;
695 Last : out Natural)
is
begin
Get_Line (Current_In, Item, Last);
end Get_Line;
700
----------
-- Getc --
----------
705 function Getc (File : File_Type) return int is
ch : int;
begin
ch := fgetc (File.Stream);
710
if ch = EOF and then ferror (File.Stream) /= 0 then
raise Device_Error;
else
return ch;
715 end if;
end Getc;
-------------
-- Is_Open --
720 -------------
function Is_Open (File : in File_Type) return Boolean is
begin
return FIO.Is_Open (AP (File));
725 end Is_Open;
----------
-- Line --
----------
730
-- Note: we assume that it is impossible in practice for the line
-- to exceed the value of Count'Last, i.e. no check is required for
-- overflow raising layout error.
735 function Line (File : in File_Type) return Positive_Count is
begin
FIO.Check_File_Open (AP (File));
return File.Line;
end Line;
740
function Line return Positive_Count is
begin
return Line (Current_Out);
end Line;
745
-----------------
-- Line_Length --
-----------------
750 function Line_Length (File : in File_Type) return Count is
begin
FIO.Check_Write_Status (AP (File));
return File.Line_Length;
end Line_Length;
755
function Line_Length return Count is
begin
return Line_Length (Current_Out);
end Line_Length;
760
----------------
-- Look_Ahead --
----------------
765 procedure Look_Ahead
(File : in File_Type;
Item : out Character;
End_Of_Line : out Boolean)
is
770 ch : int;
begin
FIO.Check_Read_Status (AP (File));
775 if File.Before_LM then
End_Of_Line := True;
Item := ASCII.NUL;
else
780 ch := Nextc (File);
if ch = LM
or else ch = EOF
or else (ch = PM and then File.Is_Regular_File)
785 then
End_Of_Line := True;
Item := ASCII.NUL;
else
End_Of_Line := False;
790 Item := Character'Val (ch);
end if;
end if;
end Look_Ahead;
795 procedure Look_Ahead
(Item : out Character;
End_Of_Line : out Boolean)
is
begin
800 Look_Ahead (Current_In, Item, End_Of_Line);
end Look_Ahead;
----------
-- Mode --
805 ----------
function Mode (File : in File_Type) return File_Mode is
begin
return To_TIO (FIO.Mode (AP (File)));
810 end Mode;
----------
-- Name --
----------
815
function Name (File : in File_Type) return String is
begin
return FIO.Name (AP (File));
end Name;
820
--------------
-- New_Line --
--------------
825 procedure New_Line
(File : in File_Type;
Spacing : in Positive_Count := 1)
is
begin
830 -- Raise Constraint_Error if out of range value. The reason for this
-- explicit test is that we don't want junk values around, even if
-- checks are off in the caller.
if Spacing not in Positive_Count then
835 raise Constraint_Error;
end if;
FIO.Check_Write_Status (AP (File));
840 for K in 1 .. Spacing loop
Putc (LM, File);
File.Line := File.Line + 1;
if File.Page_Length /= 0
845 and then File.Line > File.Page_Length
then
Putc (PM, File);
File.Line := 1;
File.Page := File.Page + 1;
850 end if;
end loop;
File.Col := 1;
end New_Line;
855
procedure New_Line (Spacing : in Positive_Count := 1) is
begin
New_Line (Current_Out, Spacing);
end New_Line;
860
--------------
-- New_Page --
--------------
865 procedure New_Page (File : in File_Type) is
begin
FIO.Check_Write_Status (AP (File));
if File.Col /= 1 or else File.Line = 1 then
870 Putc (LM, File);
end if;
Putc (PM, File);
File.Page := File.Page + 1;
875 File.Line := 1;
File.Col := 1;
end New_Page;
procedure New_Page is
880 begin
New_Page (Current_Out);
end New_Page;
-----------
885 -- Nextc --
-----------
function Nextc (File : File_Type) return int is
ch : int;
890
begin
ch := fgetc (File.Stream);
if ch = EOF then
895 if ferror (File.Stream) /= 0 then
raise Device_Error;
end if;
else
900 if ungetc (ch, File.Stream) = EOF then
raise Device_Error;
end if;
end if;
905 return ch;
end Nextc;
----------
-- Open --
910 ----------
procedure Open
(File : in out File_Type;
Mode : in File_Mode;
915 Name : in String;
Form : in String := "")
is
File_Control_Block : Text_AFCB;
920 begin
FIO.Open (File_Ptr => AP (File),
Dummy_FCB => File_Control_Block,
Mode => To_FCB (Mode),
Name => Name,
925 Form => Form,
Amethod => 'T',
Creat => False,
Text => True);
930 File.Self := File;
end Open;
----------
-- Page --
935 ----------
-- Note: we assume that it is impossible in practice for the page
-- to exceed the value of Count'Last, i.e. no check is required for
-- overflow raising layout error.
940
function Page (File : in File_Type) return Positive_Count is
begin
FIO.Check_File_Open (AP (File));
return File.Page;
945 end Page;
function Page return Positive_Count is
begin
return Page (Current_Out);
950 end Page;
-----------------
-- Page_Length --
-----------------
955
function Page_Length (File : in File_Type) return Count is
begin
FIO.Check_Write_Status (AP (File));
return File.Page_Length;
960 end Page_Length;
function Page_Length return Count is
begin
return Page_Length (Current_Out);
965 end Page_Length;
---------
-- Put --
---------
970
procedure Put
(File : in File_Type;
Item : in Character)
is
975 begin
FIO.Check_Write_Status (AP (File));
if File.Line_Length /= 0 and then File.Col > File.Line_Length then
New_Line (File);
980 end if;
if fputc (Character'Pos (Item), File.Stream) = EOF then
raise Device_Error;
end if;
985
File.Col := File.Col + 1;
end Put;
procedure Put (Item : in Character) is
990 begin
FIO.Check_Write_Status (AP (Current_Out));
if Current_Out.Line_Length /= 0
and then Current_Out.Col > Current_Out.Line_Length
995 then
New_Line (Current_Out);
end if;
if fputc (Character'Pos (Item), Current_Out.Stream) = EOF then
1000 raise Device_Error;
end if;
Current_Out.Col := Current_Out.Col + 1;
end Put;
1005
---------
-- Put --
---------
1010 procedure Put
(File : in File_Type;
Item : in String)
is
begin
1015 FIO.Check_Write_Status (AP (File));
if Item'Length > 0 then
-- If we have bounded lines, then do things character by
1020 -- character (this seems a rare case anyway!)
if File.Line_Length /= 0 then
for J in Item'Range loop
Put (File, Item (J));
1025 end loop;
-- Otherwise we can output the entire string at once. Note that if
-- there are LF or FF characters in the string, we do not bother to
-- count them as line or page terminators.
1030
else
FIO.Write_Buf (AP (File), Item'Address, Item'Length);
File.Col := File.Col + Item'Length;
end if;
1035 end if;
end Put;
procedure Put (Item : in String) is
begin
1040 Put (Current_Out, Item);
end Put;
--------------
-- Put_Line --
1045 --------------
procedure Put_Line
(File : in File_Type;
Item : in String)
1050 is
begin
FIO.Check_Write_Status (AP (File));
-- If we have bounded lines, then just do a put and a new line. In
1055 -- this case we will end up doing things character by character in
-- any case, and it is a rare situation.
if File.Line_Length /= 0 then
Put (File, Item);
1060 New_Line (File);
return;
end if;
-- We setup a single string that has the necessary terminators and
1065 -- then write it with a single call. The reason for doing this is
-- that it gives better behavior for the use of Put_Line in multi-
-- tasking programs, since often the OS will treat the entire put
-- operation as an atomic operation.
1070 declare
Ilen : constant Natural := Item'Length;
Buffer : String (1 .. Ilen + 2);
Plen : size_t;
1075 begin
Buffer (1 .. Ilen) := Item;
Buffer (Ilen + 1) := Character'Val (LM);
if File.Page_Length /= 0
1080 and then File.Line > File.Page_Length
then
Buffer (Ilen + 2) := Character'Val (PM);
Plen := size_t (Ilen) + 2;
File.Line := 1;
1085 File.Page := File.Page + 1;
else
Plen := size_t (Ilen) + 1;
File.Line := File.Line + 1;
1090 end if;
FIO.Write_Buf (AP (File), Buffer'Address, Plen);
File.Col := 1;
1095 end;
end Put_Line;
procedure Put_Line (Item : in String) is
begin
1100 Put_Line (Current_Out, Item);
end Put_Line;
----------
-- Putc --
1105 ----------
procedure Putc (ch : int; File : File_Type) is
begin
if fputc (ch, File.Stream) = EOF then
1110 raise Device_Error;
end if;
end Putc;
----------
1115 -- Read --
----------
-- This is the primitive Stream Read routine, used when a Text_IO file
-- is treated directly as a stream using Text_IO.Streams.Stream.
1120
procedure Read
(File : in out Text_AFCB;
Item : out Stream_Element_Array;
Last : out Stream_Element_Offset)
1125 is
ch : int;
begin
if File.Mode /= FCB.In_File then
1130 raise Mode_Error;
end if;
-- Deal with case where our logical and physical position do not match
-- because of being after an LM or LM-PM sequence when in fact we are
1135 -- logically positioned before it.
if File.Before_LM then
-- If we are before a PM, then it is possible for a stream read
1140 -- to leave us after the LM and before the PM, which is a bit
-- odd. The easiest way to deal with this is to unget the PM,
-- so we are indeed positioned between the characters. This way
-- further stream read operations will work correctly, and the
-- effect on text processing is a little weird, but what can
1145 -- be expected if stream and text input are mixed this way?
if File.Before_LM_PM then
ch := ungetc (PM, File.Stream);
File.Before_LM_PM := False;
1150 end if;
File.Before_LM := False;
Item (Item'First) := Stream_Element (Character'Pos (ASCII.LF));
1155
if Item'Length = 1 then
Last := Item'Last;
else
1160 Last :=
Item'First +
Stream_Element_Offset
(fread (buffer => Item'Address,
index => size_t (Item'First + 1),
1165 size => 1,
count => Item'Length - 1,
stream => File.Stream));
end if;
1170 return;
end if;
-- Now we do the read. Since this is a text file, it is normally in
-- text mode, but stream data must be read in binary mode, so we
1175 -- temporarily set binary mode for the read, resetting it after.
-- These calls have no effect in a system (like Unix) where there is
-- no distinction between text and binary files.
set_binary_mode (fileno (File.Stream));
1180
Last :=
Item'First +
Stream_Element_Offset
(fread (Item'Address, 1, Item'Length, File.Stream)) - 1;
1185
if Last < Item'Last then
if ferror (File.Stream) /= 0 then
raise Device_Error;
end if;
1190 end if;
set_text_mode (fileno (File.Stream));
end Read;
1195 -----------
-- Reset --
-----------
procedure Reset
1200 (File : in out File_Type;
Mode : in File_Mode)
is
begin
-- Don't allow change of mode for current file (RM A.10.2(5))
1205
if (File = Current_In or else
File = Current_Out or else
File = Current_Error)
and then To_FCB (Mode) /= File.Mode
1210 then
raise Mode_Error;
end if;
Terminate_Line (File);
1215 FIO.Reset (AP (File), To_FCB (Mode));
File.Page := 1;
File.Line := 1;
File.Col := 1;
File.Line_Length := 0;
1220 File.Page_Length := 0;
File.Before_LM := False;
File.Before_LM_PM := False;
end Reset;
1225 procedure Reset (File : in out File_Type) is
begin
Terminate_Line (File);
FIO.Reset (AP (File));
File.Page := 1;
1230 File.Line := 1;
File.Col := 1;
File.Line_Length := 0;
File.Page_Length := 0;
File.Before_LM := False;
1235 File.Before_LM_PM := False;
end Reset;
-------------
-- Set_Col --
1240 -------------
procedure Set_Col
(File : in File_Type;
To : in Positive_Count)
1245 is
ch : int;
begin
-- Raise Constraint_Error if out of range value. The reason for this
1250 -- explicit test is that we don't want junk values around, even if
-- checks are off in the caller.
if To not in Positive_Count then
raise Constraint_Error;
1255 end if;
FIO.Check_File_Open (AP (File));
if To = File.Col then
1260 return;
end if;
if Mode (File) >= Out_File then
if File.Line_Length /= 0 and then To > File.Line_Length then
1265 raise Layout_Error;
end if;
if To < File.Col then
New_Line (File);
1270 end if;
while File.Col < To loop
Put (File, ' ');
end loop;
1275
else
loop
ch := Getc (File);
1280 if ch = EOF then
raise End_Error;
elsif ch = LM then
File.Line := File.Line + 1;
1285 File.Col := 1;
elsif ch = PM and then File.Is_Regular_File then
File.Page := File.Page + 1;
File.Line := 1;
1290 File.Col := 1;
elsif To = File.Col then
Ungetc (ch, File);
return;
1295
else
File.Col := File.Col + 1;
end if;
end loop;
1300 end if;
end Set_Col;
procedure Set_Col (To : in Positive_Count) is
begin
1305 Set_Col (Current_Out, To);
end Set_Col;
---------------
-- Set_Error --
1310 ---------------
procedure Set_Error (File : in File_Type) is
begin
FIO.Check_Write_Status (AP (File));
1315 Current_Err := File;
end Set_Error;
---------------
-- Set_Input --
1320 ---------------
procedure Set_Input (File : in File_Type) is
begin
FIO.Check_Read_Status (AP (File));
1325 Current_In := File;
end Set_Input;
--------------
-- Set_Line --
1330 --------------
procedure Set_Line
(File : in File_Type;
To : in Positive_Count)
1335 is
begin
-- Raise Constraint_Error if out of range value. The reason for this
-- explicit test is that we don't want junk values around, even if
-- checks are off in the caller.
1340
if To not in Positive_Count then
raise Constraint_Error;
end if;
1345 FIO.Check_File_Open (AP (File));
if To = File.Line then
return;
end if;
1350
if Mode (File) >= Out_File then
if File.Page_Length /= 0 and then To > File.Page_Length then
raise Layout_Error;
end if;
1355
if To < File.Line then
New_Page (File);
end if;
1360 while File.Line < To loop
New_Line (File);
end loop;
else
1365 while To /= File.Line loop
Skip_Line (File);
end loop;
end if;
end Set_Line;
1370
procedure Set_Line (To : in Positive_Count) is
begin
Set_Line (Current_Out, To);
end Set_Line;
1375
---------------------
-- Set_Line_Length --
---------------------
1380 procedure Set_Line_Length (File : in File_Type; To : in Count) is
begin
-- Raise Constraint_Error if out of range value. The reason for this
-- explicit test is that we don't want junk values around, even if
-- checks are off in the caller.
1385
if To not in Count then
raise Constraint_Error;
end if;
1390 FIO.Check_Write_Status (AP (File));
File.Line_Length := To;
end Set_Line_Length;
procedure Set_Line_Length (To : in Count) is
1395 begin
Set_Line_Length (Current_Out, To);
end Set_Line_Length;
----------------
1400 -- Set_Output --
----------------
procedure Set_Output (File : in File_Type) is
begin
1405 FIO.Check_Write_Status (AP (File));
Current_Out := File;
end Set_Output;
---------------------
1410 -- Set_Page_Length --
---------------------
procedure Set_Page_Length (File : in File_Type; To : in Count) is
begin
1415 -- Raise Constraint_Error if out of range value. The reason for this
-- explicit test is that we don't want junk values around, even if
-- checks are off in the caller.
if To not in Count then
1420 raise Constraint_Error;
end if;
FIO.Check_Write_Status (AP (File));
File.Page_Length := To;
1425 end Set_Page_Length;
procedure Set_Page_Length (To : in Count) is
begin
Set_Page_Length (Current_Out, To);
1430 end Set_Page_Length;
---------------
-- Skip_Line --
---------------
1435
procedure Skip_Line
(File : in File_Type;
Spacing : in Positive_Count := 1)
is
1440 ch : int;
begin
-- Raise Constraint_Error if out of range value. The reason for this
-- explicit test is that we don't want junk values around, even if
1445 -- checks are off in the caller.
if Spacing not in Positive_Count then
raise Constraint_Error;
end if;
1450
FIO.Check_Read_Status (AP (File));
for L in 1 .. Spacing loop
if File.Before_LM then
1455 File.Before_LM := False;
File.Before_LM_PM := False;
else
ch := Getc (File);
1460
-- If at end of file now, then immediately raise End_Error. Note
-- that we can never be positioned between a line mark and a page
-- mark, so if we are at the end of file, we cannot logically be
-- before the implicit page mark that is at the end of the file.
1465
-- For the same reason, we do not need an explicit check for a
-- page mark. If there is a FF in the middle of a line, the file
-- is not in canonical format and we do not care about the page
-- numbers for files other than ones in canonical format.
1470
if ch = EOF then
raise End_Error;
end if;
1475 -- If not at end of file, then loop till we get to an LM or EOF.
-- The latter case happens only in non-canonical files where the
-- last line is not terminated by LM, but we don't want to blow
-- up for such files, so we assume an implicit LM in this case.
1480 loop
exit when ch = LM or ch = EOF;
ch := Getc (File);
end loop;
end if;
1485
-- We have got past a line mark, now, for a regular file only,
-- see if a page mark immediately follows this line mark and
-- if so, skip past the page mark as well. We do not do this
-- for non-regular files, since it would cause an undesirable
1490 -- wait for an additional character.
File.Col := 1;
File.Line := File.Line + 1;
1495 if File.Before_LM_PM then
File.Page := File.Page + 1;
File.Line := 1;
File.Before_LM_PM := False;
1500 elsif File.Is_Regular_File then
ch := Getc (File);
-- Page mark can be explicit, or implied at the end of the file
1505 if (ch = PM or else ch = EOF)
and then File.Is_Regular_File
then
File.Page := File.Page + 1;
File.Line := 1;
1510 else
Ungetc (ch, File);
end if;
end if;
1515 end loop;
end Skip_Line;
procedure Skip_Line (Spacing : in Positive_Count := 1) is
begin
1520 Skip_Line (Current_In, Spacing);
end Skip_Line;
---------------
-- Skip_Page --
1525 ---------------
procedure Skip_Page (File : in File_Type) is
ch : int;
1530 begin
FIO.Check_Read_Status (AP (File));
-- If at page mark already, just skip it
1535 if File.Before_LM_PM then
File.Before_LM := False;
File.Before_LM_PM := False;
File.Page := File.Page + 1;
File.Line := 1;
1540 File.Col := 1;
return;
end if;
-- This is a bit tricky, if we are logically before an LM then
1545 -- it is not an error if we are at an end of file now, since we
-- are not really at it.
if File.Before_LM then
File.Before_LM := False;
1550 File.Before_LM_PM := False;
ch := Getc (File);
-- Otherwise we do raise End_Error if we are at the end of file now
1555 else
ch := Getc (File);
if ch = EOF then
raise End_Error;
1560 end if;
end if;
-- Now we can just rumble along to the next page mark, or to the
-- end of file, if that comes first. The latter case happens when
1565 -- the page mark is implied at the end of file.
loop
exit when ch = EOF
or else (ch = PM and then File.Is_Regular_File);
1570 ch := Getc (File);
end loop;
File.Page := File.Page + 1;
File.Line := 1;
1575 File.Col := 1;
end Skip_Page;
procedure Skip_Page is
begin
1580 Skip_Page (Current_In);
end Skip_Page;
--------------------
-- Standard_Error --
1585 --------------------
function Standard_Error return File_Type is
begin
return Standard_Err;
1590 end Standard_Error;
function Standard_Error return File_Access is
begin
return Standard_Err'Access;
1595 end Standard_Error;
--------------------
-- Standard_Input --
--------------------
1600
function Standard_Input return File_Type is
begin
return Standard_In;
end Standard_Input;
1605
function Standard_Input return File_Access is
begin
return Standard_In'Access;
end Standard_Input;
1610
---------------------
-- Standard_Output --
---------------------
1615 function Standard_Output return File_Type is
begin
return Standard_Out;
end Standard_Output;
1620 function Standard_Output return File_Access is
begin
return Standard_Out'Access;
end Standard_Output;
1625 --------------------
-- Terminate_Line --
--------------------
procedure Terminate_Line (File : File_Type) is
1630 begin
FIO.Check_File_Open (AP (File));
-- For file other than In_File, test for needing to terminate last line
1635 if Mode (File) /= In_File then
-- If not at start of line definition need new line
if File.Col /= 1 then
1640 New_Line (File);
-- For files other than standard error and standard output, we
-- make sure that an empty file has a single line feed, so that
-- it is properly formatted. We avoid this for the standard files
1645 -- because it is too much of a nuisance to have these odd line
-- feeds when nothing has been written to the file.
elsif (File /= Standard_Err and then File /= Standard_Out)
and then (File.Line = 1 and then File.Page = 1)
1650 then
New_Line (File);
end if;
end if;
end Terminate_Line;
1655
------------
-- Ungetc --
------------
1660 procedure Ungetc (ch : int; File : File_Type) is
begin
if ch /= EOF then
if ungetc (ch, File.Stream) = EOF then
raise Device_Error;
1665 end if;
end if;
end Ungetc;
-----------
1670 -- Write --
-----------
-- This is the primitive Stream Write routine, used when a Text_IO file
-- is treated directly as a stream using Text_IO.Streams.Stream.
1675
procedure Write
(File : in out Text_AFCB;
Item : in Stream_Element_Array)
is
1680
function Has_Translated_Characters return Boolean;
-- return True if Item array contains a character which will be
-- translated under the text file mode. There is only one such
-- character under DOS based systems which is character 10.
1685
text_translation_required : Boolean;
pragma Import (C, text_translation_required,
"__gnat_text_translation_required");
1690 Siz : constant size_t := Item'Length;
function Has_Translated_Characters return Boolean is
begin
for K in Item'Range loop
1695 if Item (K) = 10 then
return True;
end if;
end loop;
return False;
1700 end Has_Translated_Characters;
Needs_Binary_Write : constant Boolean :=
text_translation_required and then Has_Translated_Characters;
1705 begin
if File.Mode = FCB.In_File then
raise Mode_Error;
end if;
1710 -- Now we do the write. Since this is a text file, it is normally in
-- text mode, but stream data must be written in binary mode, so we
-- temporarily set binary mode for the write, resetting it after. This
-- is done only if needed (i.e. there is some characters in Item which
-- needs to be written using the binary mode).
1715 -- These calls have no effect in a system (like Unix) where there is
-- no distinction between text and binary files.
-- Since the character translation is done at the time the buffer is
-- written (this is true under Windows) we first flush current buffer
1720 -- with text mode if needed.
if Needs_Binary_Write then
if fflush (File.Stream) = -1 then
1725 raise Device_Error;
end if;
set_binary_mode (fileno (File.Stream));
end if;
1730
if fwrite (Item'Address, 1, Siz, File.Stream) /= Siz then
raise Device_Error;
end if;
1735 -- At this point we need to flush the buffer using the binary mode then
-- we reset to text mode.
if Needs_Binary_Write then
1740 if fflush (File.Stream) = -1 then
raise Device_Error;
end if;
set_text_mode (fileno (File.Stream));
1745 end if;
end Write;
-- Use "preallocated" strings to avoid calling "new" during the
-- elaboration of the run time. This is needed in the tasking case to
1750 -- avoid calling Task_Lock too early. A filename is expected to end with a
-- null character in the runtime, here the null characters are added just
-- to have a correct filename length.
Err_Name : aliased String := "*stderr" & ASCII.Nul;
1755 In_Name : aliased String := "*stdin" & ASCII.Nul;
Out_Name : aliased String := "*stdout" & ASCII.Nul;
begin
-------------------------------
-- Initialize Standard Files --
1760 -------------------------------
-- Note: the names in these files are bogus, and probably it would be
-- better for these files to have no names, but the ACVC test insist!
-- We use names that are bound to fail in open etc.
1765
Standard_Err.Stream := stderr;
Standard_Err.Name := Err_Name'Access;
Standard_Err.Form := Null_Str'Unrestricted_Access;
Standard_Err.Mode := FCB.Out_File;
1770 Standard_Err.Is_Regular_File := is_regular_file (fileno (stderr)) /= 0;
Standard_Err.Is_Temporary_File := False;
Standard_Err.Is_System_File := True;
Standard_Err.Is_Text_File := True;
Standard_Err.Access_Method := 'T';
1775 Standard_Err.Self := Standard_Err;
Standard_In.Stream := stdin;
Standard_In.Name := In_Name'Access;
Standard_In.Form := Null_Str'Unrestricted_Access;
1780 Standard_In.Mode := FCB.In_File;
Standard_In.Is_Regular_File := is_regular_file (fileno (stdin)) /= 0;
Standard_In.Is_Temporary_File := False;
Standard_In.Is_System_File := True;
Standard_In.Is_Text_File := True;
1785 Standard_In.Access_Method := 'T';
Standard_In.Self := Standard_In;
Standard_Out.Stream := stdout;
Standard_Out.Name := Out_Name'Access;
1790 Standard_Out.Form := Null_Str'Unrestricted_Access;
Standard_Out.Mode := FCB.Out_File;
Standard_Out.Is_Regular_File := is_regular_file (fileno (stdout)) /= 0;
Standard_Out.Is_Temporary_File := False;
Standard_Out.Is_System_File := True;
1795 Standard_Out.Is_Text_File := True;
Standard_Out.Access_Method := 'T';
Standard_Out.Self := Standard_Out;
FIO.Chain_File (AP (Standard_In));
1800 FIO.Chain_File (AP (Standard_Out));
FIO.Chain_File (AP (Standard_Err));
FIO.Make_Unbuffered (AP (Standard_Out));
FIO.Make_Unbuffered (AP (Standard_Err));
1805
end Ada.Text_IO;