File : a-textio.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- A D A . T E X T _ I O --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2016, Free Software Foundation, Inc. --
10 -- --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 3, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. --
17 -- --
18 -- --
19 -- --
20 -- --
21 -- --
22 -- You should have received a copy of the GNU General Public License and --
23 -- a copy of the GCC Runtime Library Exception along with this program; --
24 -- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
25 -- <http://www.gnu.org/licenses/>. --
26 -- --
27 -- GNAT was originally developed by the GNAT team at New York University. --
28 -- Extensive contributions were provided by Ada Core Technologies Inc. --
29 -- --
30 ------------------------------------------------------------------------------
31
32 with Ada.Streams; use Ada.Streams;
33 with Interfaces.C_Streams; use Interfaces.C_Streams;
34
35 with System.File_IO;
36 with System.CRTL;
37 with System.WCh_Cnv; use System.WCh_Cnv;
38 with System.WCh_Con; use System.WCh_Con;
39
40 with Ada.Unchecked_Conversion;
41 with Ada.Unchecked_Deallocation;
42
43 pragma Elaborate_All (System.File_IO);
44 -- Needed because of calls to Chain_File in package body elaboration
45
46 package body Ada.Text_IO is
47
48 package FIO renames System.File_IO;
49
50 subtype AP is FCB.AFCB_Ptr;
51
52 function To_FCB is new Ada.Unchecked_Conversion (File_Mode, FCB.File_Mode);
53 function To_TIO is new Ada.Unchecked_Conversion (FCB.File_Mode, File_Mode);
54 use type FCB.File_Mode;
55
56 use type System.CRTL.size_t;
57
58 WC_Encoding : Character;
59 pragma Import (C, WC_Encoding, "__gl_wc_encoding");
60 -- Default wide character encoding
61
62 Err_Name : aliased String := "*stderr" & ASCII.NUL;
63 In_Name : aliased String := "*stdin" & ASCII.NUL;
64 Out_Name : aliased String := "*stdout" & ASCII.NUL;
65 -- Names of standard files
66 --
67 -- Use "preallocated" strings to avoid calling "new" during the elaboration
68 -- of the run time. This is needed in the tasking case to avoid calling
69 -- Task_Lock too early. A filename is expected to end with a null character
70 -- in the runtime, here the null characters are added just to have a
71 -- correct filename length.
72 --
73 -- Note: the names for these files are bogus, and probably it would be
74 -- better for these files to have no names, but the ACVC tests insist.
75 -- We use names that are bound to fail in open etc.
76
77 Null_Str : aliased constant String := "";
78 -- Used as form string for standard files
79
80 -----------------------
81 -- Local Subprograms --
82 -----------------------
83
84 function Get_Upper_Half_Char
85 (C : Character;
86 File : File_Type) return Character;
87 -- This function is shared by Get and Get_Immediate to extract an encoded
88 -- upper half character value from the given File. The first byte has
89 -- already been read and is passed in C. The character value is returned as
90 -- the result, and the file pointer is bumped past the character.
91 -- Constraint_Error is raised if the encoded value is outside the bounds of
92 -- type Character.
93
94 function Get_Upper_Half_Char_Immed
95 (C : Character;
96 File : File_Type) return Character;
97 -- This routine is identical to Get_Upper_Half_Char, except that the reads
98 -- are done in Get_Immediate mode (i.e. without waiting for a line return).
99
100 function Getc (File : File_Type) return int;
101 -- Gets next character from file, which has already been checked for being
102 -- in read status, and returns the character read if no error occurs. The
103 -- result is EOF if the end of file was read.
104
105 function Getc_Immed (File : File_Type) return int;
106 -- This routine is identical to Getc, except that the read is done in
107 -- Get_Immediate mode (i.e. without waiting for a line return).
108
109 function Has_Upper_Half_Character (Item : String) return Boolean;
110 -- Returns True if any of the characters is in the range 16#80#-16#FF#
111
112 function Nextc (File : File_Type) return int;
113 -- Returns next character from file without skipping past it (i.e. it is a
114 -- combination of Getc followed by an Ungetc).
115
116 procedure Put_Encoded (File : File_Type; Char : Character);
117 -- Called to output a character Char to the given File, when the encoding
118 -- method for the file is other than brackets, and Char is upper half.
119
120 procedure Putc (ch : int; File : File_Type);
121 -- Outputs the given character to the file, which has already been checked
122 -- for being in output status. Device_Error is raised if the character
123 -- cannot be written.
124
125 procedure Set_WCEM (File : in out File_Type);
126 -- Called by Open and Create to set the wide character encoding method for
127 -- the file, processing a WCEM form parameter if one is present. File is
128 -- IN OUT because it may be closed in case of an error.
129
130 procedure Terminate_Line (File : File_Type);
131 -- If the file is in Write_File or Append_File mode, and the current line
132 -- is not terminated, then a line terminator is written using New_Line.
133 -- Note that there is no Terminate_Page routine, because the page mark at
134 -- the end of the file is implied if necessary.
135
136 procedure Ungetc (ch : int; File : File_Type);
137 -- Pushes back character into stream, using ungetc. The caller has checked
138 -- that the file is in read status. Device_Error is raised if the character
139 -- cannot be pushed back. An attempt to push back and end of file character
140 -- (EOF) is ignored.
141
142 -------------------
143 -- AFCB_Allocate --
144 -------------------
145
146 function AFCB_Allocate (Control_Block : Text_AFCB) return FCB.AFCB_Ptr is
147 pragma Unreferenced (Control_Block);
148 begin
149 return new Text_AFCB;
150 end AFCB_Allocate;
151
152 ----------------
153 -- AFCB_Close --
154 ----------------
155
156 procedure AFCB_Close (File : not null access Text_AFCB) is
157 begin
158 -- If the file being closed is one of the current files, then close
159 -- the corresponding current file. It is not clear that this action
160 -- is required (RM A.10.3(23)) but it seems reasonable, and besides
161 -- ACVC test CE3208A expects this behavior.
162
163 if File_Type (File) = Current_In then
164 Current_In := null;
165 elsif File_Type (File) = Current_Out then
166 Current_Out := null;
167 elsif File_Type (File) = Current_Err then
168 Current_Err := null;
169 end if;
170
171 Terminate_Line (File_Type (File));
172 end AFCB_Close;
173
174 ---------------
175 -- AFCB_Free --
176 ---------------
177
178 procedure AFCB_Free (File : not null access Text_AFCB) is
179 type FCB_Ptr is access all Text_AFCB;
180 FT : FCB_Ptr := FCB_Ptr (File);
181
182 procedure Free is new Ada.Unchecked_Deallocation (Text_AFCB, FCB_Ptr);
183
184 begin
185 Free (FT);
186 end AFCB_Free;
187
188 -----------
189 -- Close --
190 -----------
191
192 procedure Close (File : in out File_Type) is
193 begin
194 FIO.Close (AP (File)'Unrestricted_Access);
195 end Close;
196
197 ---------
198 -- Col --
199 ---------
200
201 -- Note: we assume that it is impossible in practice for the column
202 -- to exceed the value of Count'Last, i.e. no check is required for
203 -- overflow raising layout error.
204
205 function Col (File : File_Type) return Positive_Count is
206 begin
207 FIO.Check_File_Open (AP (File));
208 return File.Col;
209 end Col;
210
211 function Col return Positive_Count is
212 begin
213 return Col (Current_Out);
214 end Col;
215
216 ------------
217 -- Create --
218 ------------
219
220 procedure Create
221 (File : in out File_Type;
222 Mode : File_Mode := Out_File;
223 Name : String := "";
224 Form : String := "")
225 is
226 Dummy_File_Control_Block : Text_AFCB;
227 pragma Warnings (Off, Dummy_File_Control_Block);
228 -- Yes, we know this is never assigned a value, only the tag
229 -- is used for dispatching purposes, so that's expected.
230
231 begin
232 FIO.Open (File_Ptr => AP (File),
233 Dummy_FCB => Dummy_File_Control_Block,
234 Mode => To_FCB (Mode),
235 Name => Name,
236 Form => Form,
237 Amethod => 'T',
238 Creat => True,
239 Text => True);
240
241 File.Self := File;
242 Set_WCEM (File);
243 end Create;
244
245 -------------------
246 -- Current_Error --
247 -------------------
248
249 function Current_Error return File_Type is
250 begin
251 return Current_Err;
252 end Current_Error;
253
254 function Current_Error return File_Access is
255 begin
256 return Current_Err.Self'Access;
257 end Current_Error;
258
259 -------------------
260 -- Current_Input --
261 -------------------
262
263 function Current_Input return File_Type is
264 begin
265 return Current_In;
266 end Current_Input;
267
268 function Current_Input return File_Access is
269 begin
270 return Current_In.Self'Access;
271 end Current_Input;
272
273 --------------------
274 -- Current_Output --
275 --------------------
276
277 function Current_Output return File_Type is
278 begin
279 return Current_Out;
280 end Current_Output;
281
282 function Current_Output return File_Access is
283 begin
284 return Current_Out.Self'Access;
285 end Current_Output;
286
287 ------------
288 -- Delete --
289 ------------
290
291 procedure Delete (File : in out File_Type) is
292 begin
293 FIO.Delete (AP (File)'Unrestricted_Access);
294 end Delete;
295
296 -----------------
297 -- End_Of_File --
298 -----------------
299
300 function End_Of_File (File : File_Type) return Boolean is
301 ch : int;
302
303 begin
304 FIO.Check_Read_Status (AP (File));
305
306 if File.Before_Upper_Half_Character then
307 return False;
308
309 elsif File.Before_LM then
310 if File.Before_LM_PM then
311 return Nextc (File) = EOF;
312 end if;
313
314 else
315 ch := Getc (File);
316
317 if ch = EOF then
318 return True;
319
320 elsif ch /= LM then
321 Ungetc (ch, File);
322 return False;
323
324 else -- ch = LM
325 File.Before_LM := True;
326 end if;
327 end if;
328
329 -- 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
331 -- to back up more than one character.
332
333 ch := Getc (File);
334
335 if ch = EOF then
336 return True;
337
338 elsif ch = PM and then File.Is_Regular_File then
339 File.Before_LM_PM := True;
340 return Nextc (File) = EOF;
341
342 -- Here if neither EOF nor PM followed end of line
343
344 else
345 Ungetc (ch, File);
346 return False;
347 end if;
348
349 end End_Of_File;
350
351 function End_Of_File return Boolean is
352 begin
353 return End_Of_File (Current_In);
354 end End_Of_File;
355
356 -----------------
357 -- End_Of_Line --
358 -----------------
359
360 function End_Of_Line (File : File_Type) return Boolean is
361 ch : int;
362
363 begin
364 FIO.Check_Read_Status (AP (File));
365
366 if File.Before_Upper_Half_Character then
367 return False;
368
369 elsif File.Before_LM then
370 return True;
371
372 else
373 ch := Getc (File);
374
375 if ch = EOF then
376 return True;
377
378 else
379 Ungetc (ch, File);
380 return (ch = LM);
381 end if;
382 end if;
383 end End_Of_Line;
384
385 function End_Of_Line return Boolean is
386 begin
387 return End_Of_Line (Current_In);
388 end End_Of_Line;
389
390 -----------------
391 -- End_Of_Page --
392 -----------------
393
394 function End_Of_Page (File : File_Type) return Boolean is
395 ch : int;
396
397 begin
398 FIO.Check_Read_Status (AP (File));
399
400 if not File.Is_Regular_File then
401 return False;
402
403 elsif File.Before_Upper_Half_Character then
404 return False;
405
406 elsif File.Before_LM then
407 if File.Before_LM_PM then
408 return True;
409 end if;
410
411 else
412 ch := Getc (File);
413
414 if ch = EOF then
415 return True;
416
417 elsif ch /= LM then
418 Ungetc (ch, File);
419 return False;
420
421 else -- ch = LM
422 File.Before_LM := True;
423 end if;
424 end if;
425
426 -- Here we are just past the line mark with Before_LM set so that we
427 -- do not have to try to back up past the LM, thus avoiding the need
428 -- to back up more than one character.
429
430 ch := Nextc (File);
431
432 return ch = PM or else ch = EOF;
433 end End_Of_Page;
434
435 function End_Of_Page return Boolean is
436 begin
437 return End_Of_Page (Current_In);
438 end End_Of_Page;
439
440 --------------
441 -- EOF_Char --
442 --------------
443
444 function EOF_Char return Integer is
445 begin
446 return EOF;
447 end EOF_Char;
448
449 -----------
450 -- Flush --
451 -----------
452
453 procedure Flush (File : File_Type) is
454 begin
455 FIO.Flush (AP (File));
456 end Flush;
457
458 procedure Flush is
459 begin
460 Flush (Current_Out);
461 end Flush;
462
463 ----------
464 -- Form --
465 ----------
466
467 function Form (File : File_Type) return String is
468 begin
469 return FIO.Form (AP (File));
470 end Form;
471
472 ---------
473 -- Get --
474 ---------
475
476 procedure Get
477 (File : File_Type;
478 Item : out Character)
479 is
480 ch : int;
481
482 begin
483 FIO.Check_Read_Status (AP (File));
484
485 if File.Before_Upper_Half_Character then
486 File.Before_Upper_Half_Character := False;
487 Item := File.Saved_Upper_Half_Character;
488
489 elsif File.Before_LM then
490 File.Before_LM := False;
491 File.Col := 1;
492
493 if File.Before_LM_PM then
494 File.Line := 1;
495 File.Page := File.Page + 1;
496 File.Before_LM_PM := False;
497 else
498 File.Line := File.Line + 1;
499 end if;
500 end if;
501
502 loop
503 ch := Getc (File);
504
505 if ch = EOF then
506 raise End_Error;
507
508 elsif ch = LM then
509 File.Line := File.Line + 1;
510 File.Col := 1;
511
512 elsif ch = PM and then File.Is_Regular_File then
513 File.Page := File.Page + 1;
514 File.Line := 1;
515
516 else
517 Item := Character'Val (ch);
518 File.Col := File.Col + 1;
519 return;
520 end if;
521 end loop;
522 end Get;
523
524 procedure Get (Item : out Character) is
525 begin
526 Get (Current_In, Item);
527 end Get;
528
529 procedure Get
530 (File : File_Type;
531 Item : out String)
532 is
533 ch : int;
534 J : Natural;
535
536 begin
537 FIO.Check_Read_Status (AP (File));
538
539 if File.Before_LM then
540 File.Before_LM := False;
541 File.Before_LM_PM := False;
542 File.Col := 1;
543
544 if File.Before_LM_PM then
545 File.Line := 1;
546 File.Page := File.Page + 1;
547 File.Before_LM_PM := False;
548
549 else
550 File.Line := File.Line + 1;
551 end if;
552 end if;
553
554 J := Item'First;
555 while J <= Item'Last loop
556 ch := Getc (File);
557
558 if ch = EOF then
559 raise End_Error;
560
561 elsif ch = LM then
562 File.Line := File.Line + 1;
563 File.Col := 1;
564
565 elsif ch = PM and then File.Is_Regular_File then
566 File.Page := File.Page + 1;
567 File.Line := 1;
568
569 else
570 Item (J) := Character'Val (ch);
571 J := J + 1;
572 File.Col := File.Col + 1;
573 end if;
574 end loop;
575 end Get;
576
577 procedure Get (Item : out String) is
578 begin
579 Get (Current_In, Item);
580 end Get;
581
582 -------------------
583 -- Get_Immediate --
584 -------------------
585
586 procedure Get_Immediate
587 (File : File_Type;
588 Item : out Character)
589 is
590 ch : int;
591
592 begin
593 FIO.Check_Read_Status (AP (File));
594
595 if File.Before_Upper_Half_Character then
596 File.Before_Upper_Half_Character := False;
597 Item := File.Saved_Upper_Half_Character;
598
599 elsif File.Before_LM then
600 File.Before_LM := False;
601 File.Before_LM_PM := False;
602 Item := Character'Val (LM);
603
604 else
605 ch := Getc_Immed (File);
606
607 if ch = EOF then
608 raise End_Error;
609 else
610 Item :=
611 (if not Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method)
612 then Character'Val (ch)
613 else Get_Upper_Half_Char_Immed (Character'Val (ch), File));
614 end if;
615 end if;
616 end Get_Immediate;
617
618 procedure Get_Immediate
619 (Item : out Character)
620 is
621 begin
622 Get_Immediate (Current_In, Item);
623 end Get_Immediate;
624
625 procedure Get_Immediate
626 (File : File_Type;
627 Item : out Character;
628 Available : out Boolean)
629 is
630 ch : int;
631 end_of_file : int;
632 avail : int;
633
634 procedure getc_immediate_nowait
635 (stream : FILEs;
636 ch : out int;
637 end_of_file : out int;
638 avail : out int);
639 pragma Import (C, getc_immediate_nowait, "getc_immediate_nowait");
640
641 begin
642 FIO.Check_Read_Status (AP (File));
643 Available := True;
644
645 if File.Before_Upper_Half_Character then
646 File.Before_Upper_Half_Character := False;
647 Item := File.Saved_Upper_Half_Character;
648
649 elsif File.Before_LM then
650 File.Before_LM := False;
651 File.Before_LM_PM := False;
652 Item := Character'Val (LM);
653
654 else
655 getc_immediate_nowait (File.Stream, ch, end_of_file, avail);
656
657 if ferror (File.Stream) /= 0 then
658 raise Device_Error;
659
660 elsif end_of_file /= 0 then
661 raise End_Error;
662
663 elsif avail = 0 then
664 Available := False;
665 Item := ASCII.NUL;
666
667 else
668 Available := True;
669
670 Item :=
671 (if not Is_Start_Of_Encoding (Character'Val (ch), File.WC_Method)
672 then Character'Val (ch)
673 else Get_Upper_Half_Char_Immed (Character'Val (ch), File));
674 end if;
675 end if;
676
677 end Get_Immediate;
678
679 procedure Get_Immediate
680 (Item : out Character;
681 Available : out Boolean)
682 is
683 begin
684 Get_Immediate (Current_In, Item, Available);
685 end Get_Immediate;
686
687 --------------
688 -- Get_Line --
689 --------------
690
691 procedure Get_Line
692 (File : File_Type;
693 Item : out String;
694 Last : out Natural) is separate;
695 -- The implementation of Ada.Text_IO.Get_Line is split into a subunit so
696 -- that different implementations can be used on different systems.
697
698 procedure Get_Line
699 (Item : out String;
700 Last : out Natural)
701 is
702 begin
703 Get_Line (Current_In, Item, Last);
704 end Get_Line;
705
706 function Get_Line (File : File_Type) return String is
707 function Get_Rest (S : String) return String;
708 -- This is a recursive function that reads the rest of the line and
709 -- returns it. S is the part read so far.
710
711 --------------
712 -- Get_Rest --
713 --------------
714
715 function Get_Rest (S : String) return String is
716
717 -- The first time we allocate a buffer of size 500. Each following
718 -- time we allocate a buffer the same size as what we have read so
719 -- far. This limits us to a logarithmic number of calls to Get_Rest
720 -- and also ensures only a linear use of stack space.
721
722 Buffer : String (1 .. Integer'Max (500, S'Length));
723 Last : Natural;
724
725 begin
726 Get_Line (File, Buffer, Last);
727
728 declare
729 R : constant String := S & Buffer (1 .. Last);
730 begin
731 if Last < Buffer'Last then
732 return R;
733
734 else
735 pragma Assert (Last = Buffer'Last);
736
737 -- If the String has the same length as the buffer, and there
738 -- is no end of line, check whether we are at the end of file,
739 -- in which case we have the full String in the buffer.
740
741 if End_Of_File (File) then
742 return R;
743
744 else
745 return Get_Rest (R);
746 end if;
747 end if;
748 end;
749 end Get_Rest;
750
751 -- Start of processing for Get_Line
752
753 begin
754 return Get_Rest ("");
755 end Get_Line;
756
757 function Get_Line return String is
758 begin
759 return Get_Line (Current_In);
760 end Get_Line;
761
762 -------------------------
763 -- Get_Upper_Half_Char --
764 -------------------------
765
766 function Get_Upper_Half_Char
767 (C : Character;
768 File : File_Type) return Character
769 is
770 Result : Wide_Character;
771
772 function In_Char return Character;
773 -- Function used to obtain additional characters it the wide character
774 -- sequence is more than one character long.
775
776 function WC_In is new Char_Sequence_To_Wide_Char (In_Char);
777
778 -------------
779 -- In_Char --
780 -------------
781
782 function In_Char return Character is
783 ch : constant Integer := Getc (File);
784 begin
785 if ch = EOF then
786 raise End_Error;
787 else
788 return Character'Val (ch);
789 end if;
790 end In_Char;
791
792 -- Start of processing for Get_Upper_Half_Char
793
794 begin
795 Result := WC_In (C, File.WC_Method);
796
797 if Wide_Character'Pos (Result) > 16#FF# then
798 raise Constraint_Error with
799 "invalid wide character in Text_'I'O input";
800 else
801 return Character'Val (Wide_Character'Pos (Result));
802 end if;
803 end Get_Upper_Half_Char;
804
805 -------------------------------
806 -- Get_Upper_Half_Char_Immed --
807 -------------------------------
808
809 function Get_Upper_Half_Char_Immed
810 (C : Character;
811 File : File_Type) return Character
812 is
813 Result : Wide_Character;
814
815 function In_Char return Character;
816 -- Function used to obtain additional characters it the wide character
817 -- sequence is more than one character long.
818
819 function WC_In is new Char_Sequence_To_Wide_Char (In_Char);
820
821 -------------
822 -- In_Char --
823 -------------
824
825 function In_Char return Character is
826 ch : constant Integer := Getc_Immed (File);
827 begin
828 if ch = EOF then
829 raise End_Error;
830 else
831 return Character'Val (ch);
832 end if;
833 end In_Char;
834
835 -- Start of processing for Get_Upper_Half_Char_Immed
836
837 begin
838 Result := WC_In (C, File.WC_Method);
839
840 if Wide_Character'Pos (Result) > 16#FF# then
841 raise Constraint_Error with
842 "invalid wide character in Text_'I'O input";
843 else
844 return Character'Val (Wide_Character'Pos (Result));
845 end if;
846 end Get_Upper_Half_Char_Immed;
847
848 ----------
849 -- Getc --
850 ----------
851
852 function Getc (File : File_Type) return int is
853 ch : int;
854
855 begin
856 ch := fgetc (File.Stream);
857
858 if ch = EOF and then ferror (File.Stream) /= 0 then
859 raise Device_Error;
860 else
861 return ch;
862 end if;
863 end Getc;
864
865 ----------------
866 -- Getc_Immed --
867 ----------------
868
869 function Getc_Immed (File : File_Type) return int is
870 ch : int;
871 end_of_file : int;
872
873 procedure getc_immediate
874 (stream : FILEs; ch : out int; end_of_file : out int);
875 pragma Import (C, getc_immediate, "getc_immediate");
876
877 begin
878 FIO.Check_Read_Status (AP (File));
879
880 if File.Before_LM then
881 File.Before_LM := False;
882 File.Before_LM_PM := False;
883 ch := LM;
884
885 else
886 getc_immediate (File.Stream, ch, end_of_file);
887
888 if ferror (File.Stream) /= 0 then
889 raise Device_Error;
890 elsif end_of_file /= 0 then
891 return EOF;
892 end if;
893 end if;
894
895 return ch;
896 end Getc_Immed;
897
898 ------------------------------
899 -- Has_Upper_Half_Character --
900 ------------------------------
901
902 function Has_Upper_Half_Character (Item : String) return Boolean is
903 begin
904 for J in Item'Range loop
905 if Character'Pos (Item (J)) >= 16#80# then
906 return True;
907 end if;
908 end loop;
909
910 return False;
911 end Has_Upper_Half_Character;
912
913 -------------------------------
914 -- Initialize_Standard_Files --
915 -------------------------------
916
917 procedure Initialize_Standard_Files is
918 begin
919 Standard_Err.Stream := stderr;
920 Standard_Err.Name := Err_Name'Access;
921 Standard_Err.Form := Null_Str'Unrestricted_Access;
922 Standard_Err.Mode := FCB.Out_File;
923 Standard_Err.Is_Regular_File := is_regular_file (fileno (stderr)) /= 0;
924 Standard_Err.Is_Temporary_File := False;
925 Standard_Err.Is_System_File := True;
926 Standard_Err.Text_Encoding := Default_Text;
927 Standard_Err.Access_Method := 'T';
928 Standard_Err.Self := Standard_Err;
929 Standard_Err.WC_Method := Default_WCEM;
930
931 Standard_In.Stream := stdin;
932 Standard_In.Name := In_Name'Access;
933 Standard_In.Form := Null_Str'Unrestricted_Access;
934 Standard_In.Mode := FCB.In_File;
935 Standard_In.Is_Regular_File := is_regular_file (fileno (stdin)) /= 0;
936 Standard_In.Is_Temporary_File := False;
937 Standard_In.Is_System_File := True;
938 Standard_In.Text_Encoding := Default_Text;
939 Standard_In.Access_Method := 'T';
940 Standard_In.Self := Standard_In;
941 Standard_In.WC_Method := Default_WCEM;
942
943 Standard_Out.Stream := stdout;
944 Standard_Out.Name := Out_Name'Access;
945 Standard_Out.Form := Null_Str'Unrestricted_Access;
946 Standard_Out.Mode := FCB.Out_File;
947 Standard_Out.Is_Regular_File := is_regular_file (fileno (stdout)) /= 0;
948 Standard_Out.Is_Temporary_File := False;
949 Standard_Out.Is_System_File := True;
950 Standard_Out.Text_Encoding := Default_Text;
951 Standard_Out.Access_Method := 'T';
952 Standard_Out.Self := Standard_Out;
953 Standard_Out.WC_Method := Default_WCEM;
954
955 FIO.Make_Unbuffered (AP (Standard_Out));
956 FIO.Make_Unbuffered (AP (Standard_Err));
957 end Initialize_Standard_Files;
958
959 -------------
960 -- Is_Open --
961 -------------
962
963 function Is_Open (File : File_Type) return Boolean is
964 begin
965 return FIO.Is_Open (AP (File));
966 end Is_Open;
967
968 ----------
969 -- Line --
970 ----------
971
972 -- Note: we assume that it is impossible in practice for the line
973 -- to exceed the value of Count'Last, i.e. no check is required for
974 -- overflow raising layout error.
975
976 function Line (File : File_Type) return Positive_Count is
977 begin
978 FIO.Check_File_Open (AP (File));
979 return File.Line;
980 end Line;
981
982 function Line return Positive_Count is
983 begin
984 return Line (Current_Out);
985 end Line;
986
987 -----------------
988 -- Line_Length --
989 -----------------
990
991 function Line_Length (File : File_Type) return Count is
992 begin
993 FIO.Check_Write_Status (AP (File));
994 return File.Line_Length;
995 end Line_Length;
996
997 function Line_Length return Count is
998 begin
999 return Line_Length (Current_Out);
1000 end Line_Length;
1001
1002 ----------------
1003 -- Look_Ahead --
1004 ----------------
1005
1006 procedure Look_Ahead
1007 (File : File_Type;
1008 Item : out Character;
1009 End_Of_Line : out Boolean)
1010 is
1011 ch : int;
1012
1013 begin
1014 FIO.Check_Read_Status (AP (File));
1015
1016 -- If we are logically before a line mark, we can return immediately
1017
1018 if File.Before_LM then
1019 End_Of_Line := True;
1020 Item := ASCII.NUL;
1021
1022 -- If we are before an upper half character just return it (this can
1023 -- happen if there are two calls to Look_Ahead in a row).
1024
1025 elsif File.Before_Upper_Half_Character then
1026 End_Of_Line := False;
1027 Item := File.Saved_Upper_Half_Character;
1028
1029 -- Otherwise we must read a character from the input stream
1030
1031 else
1032 ch := Getc (File);
1033
1034 if ch = LM
1035 or else ch = EOF
1036 or else (ch = PM and then File.Is_Regular_File)
1037 then
1038 End_Of_Line := True;
1039 Ungetc (ch, File);
1040 Item := ASCII.NUL;
1041
1042 -- Case where character obtained does not represent the start of an
1043 -- encoded sequence so it stands for itself and we can unget it with
1044 -- no difficulty.
1045
1046 elsif not Is_Start_Of_Encoding
1047 (Character'Val (ch), File.WC_Method)
1048 then
1049 End_Of_Line := False;
1050 Ungetc (ch, File);
1051 Item := Character'Val (ch);
1052
1053 -- For the start of an encoding, we read the character using the
1054 -- Get_Upper_Half_Char routine. It will occupy more than one byte
1055 -- so we can't put it back with ungetc. Instead we save it in the
1056 -- control block, setting a flag that everyone interested in reading
1057 -- characters must test before reading the stream.
1058
1059 else
1060 Item := Get_Upper_Half_Char (Character'Val (ch), File);
1061 End_Of_Line := False;
1062 File.Saved_Upper_Half_Character := Item;
1063 File.Before_Upper_Half_Character := True;
1064 end if;
1065 end if;
1066 end Look_Ahead;
1067
1068 procedure Look_Ahead
1069 (Item : out Character;
1070 End_Of_Line : out Boolean)
1071 is
1072 begin
1073 Look_Ahead (Current_In, Item, End_Of_Line);
1074 end Look_Ahead;
1075
1076 ----------
1077 -- Mode --
1078 ----------
1079
1080 function Mode (File : File_Type) return File_Mode is
1081 begin
1082 return To_TIO (FIO.Mode (AP (File)));
1083 end Mode;
1084
1085 ----------
1086 -- Name --
1087 ----------
1088
1089 function Name (File : File_Type) return String is
1090 begin
1091 return FIO.Name (AP (File));
1092 end Name;
1093
1094 --------------
1095 -- New_Line --
1096 --------------
1097
1098 procedure New_Line
1099 (File : File_Type;
1100 Spacing : Positive_Count := 1)
1101 is
1102 begin
1103 -- Raise Constraint_Error if out of range value. The reason for this
1104 -- explicit test is that we don't want junk values around, even if
1105 -- checks are off in the caller.
1106
1107 if not Spacing'Valid then
1108 raise Constraint_Error;
1109 end if;
1110
1111 FIO.Check_Write_Status (AP (File));
1112
1113 for K in 1 .. Spacing loop
1114 Putc (LM, File);
1115 File.Line := File.Line + 1;
1116
1117 if File.Page_Length /= 0
1118 and then File.Line > File.Page_Length
1119 then
1120 Putc (PM, File);
1121 File.Line := 1;
1122 File.Page := File.Page + 1;
1123 end if;
1124 end loop;
1125
1126 File.Col := 1;
1127 end New_Line;
1128
1129 procedure New_Line (Spacing : Positive_Count := 1) is
1130 begin
1131 New_Line (Current_Out, Spacing);
1132 end New_Line;
1133
1134 --------------
1135 -- New_Page --
1136 --------------
1137
1138 procedure New_Page (File : File_Type) is
1139 begin
1140 FIO.Check_Write_Status (AP (File));
1141
1142 if File.Col /= 1 or else File.Line = 1 then
1143 Putc (LM, File);
1144 end if;
1145
1146 Putc (PM, File);
1147 File.Page := File.Page + 1;
1148 File.Line := 1;
1149 File.Col := 1;
1150 end New_Page;
1151
1152 procedure New_Page is
1153 begin
1154 New_Page (Current_Out);
1155 end New_Page;
1156
1157 -----------
1158 -- Nextc --
1159 -----------
1160
1161 function Nextc (File : File_Type) return int is
1162 ch : int;
1163
1164 begin
1165 ch := fgetc (File.Stream);
1166
1167 if ch = EOF then
1168 if ferror (File.Stream) /= 0 then
1169 raise Device_Error;
1170 end if;
1171
1172 else
1173 if ungetc (ch, File.Stream) = EOF then
1174 raise Device_Error;
1175 end if;
1176 end if;
1177
1178 return ch;
1179 end Nextc;
1180
1181 ----------
1182 -- Open --
1183 ----------
1184
1185 procedure Open
1186 (File : in out File_Type;
1187 Mode : File_Mode;
1188 Name : String;
1189 Form : String := "")
1190 is
1191 Dummy_File_Control_Block : Text_AFCB;
1192 pragma Warnings (Off, Dummy_File_Control_Block);
1193 -- Yes, we know this is never assigned a value, only the tag
1194 -- is used for dispatching purposes, so that's expected.
1195
1196 begin
1197 FIO.Open (File_Ptr => AP (File),
1198 Dummy_FCB => Dummy_File_Control_Block,
1199 Mode => To_FCB (Mode),
1200 Name => Name,
1201 Form => Form,
1202 Amethod => 'T',
1203 Creat => False,
1204 Text => True);
1205
1206 File.Self := File;
1207 Set_WCEM (File);
1208 end Open;
1209
1210 ----------
1211 -- Page --
1212 ----------
1213
1214 -- Note: we assume that it is impossible in practice for the page
1215 -- to exceed the value of Count'Last, i.e. no check is required for
1216 -- overflow raising layout error.
1217
1218 function Page (File : File_Type) return Positive_Count is
1219 begin
1220 FIO.Check_File_Open (AP (File));
1221 return File.Page;
1222 end Page;
1223
1224 function Page return Positive_Count is
1225 begin
1226 return Page (Current_Out);
1227 end Page;
1228
1229 -----------------
1230 -- Page_Length --
1231 -----------------
1232
1233 function Page_Length (File : File_Type) return Count is
1234 begin
1235 FIO.Check_Write_Status (AP (File));
1236 return File.Page_Length;
1237 end Page_Length;
1238
1239 function Page_Length return Count is
1240 begin
1241 return Page_Length (Current_Out);
1242 end Page_Length;
1243
1244 ---------
1245 -- Put --
1246 ---------
1247
1248 procedure Put
1249 (File : File_Type;
1250 Item : Character)
1251 is
1252 begin
1253 FIO.Check_Write_Status (AP (File));
1254
1255 if File.Line_Length /= 0 and then File.Col > File.Line_Length then
1256 New_Line (File);
1257 end if;
1258
1259 -- If lower half character, or brackets encoding, output directly
1260
1261 if Character'Pos (Item) < 16#80#
1262 or else File.WC_Method = WCEM_Brackets
1263 then
1264 if fputc (Character'Pos (Item), File.Stream) = EOF then
1265 raise Device_Error;
1266 end if;
1267
1268 -- Case of upper half character with non-brackets encoding
1269
1270 else
1271 Put_Encoded (File, Item);
1272 end if;
1273
1274 File.Col := File.Col + 1;
1275 end Put;
1276
1277 procedure Put (Item : Character) is
1278 begin
1279 Put (Current_Out, Item);
1280 end Put;
1281
1282 ---------
1283 -- Put --
1284 ---------
1285
1286 procedure Put
1287 (File : File_Type;
1288 Item : String)
1289 is
1290 begin
1291 FIO.Check_Write_Status (AP (File));
1292
1293 -- Only have something to do if string is non-null
1294
1295 if Item'Length > 0 then
1296
1297 -- If we have bounded lines, or if the file encoding is other than
1298 -- Brackets and the string has at least one upper half character,
1299 -- then output the string character by character.
1300
1301 if File.Line_Length /= 0
1302 or else (File.WC_Method /= WCEM_Brackets
1303 and then Has_Upper_Half_Character (Item))
1304 then
1305 for J in Item'Range loop
1306 Put (File, Item (J));
1307 end loop;
1308
1309 -- Otherwise we can output the entire string at once. Note that if
1310 -- there are LF or FF characters in the string, we do not bother to
1311 -- count them as line or page terminators.
1312
1313 else
1314 FIO.Write_Buf (AP (File), Item'Address, Item'Length);
1315 File.Col := File.Col + Item'Length;
1316 end if;
1317 end if;
1318 end Put;
1319
1320 procedure Put (Item : String) is
1321 begin
1322 Put (Current_Out, Item);
1323 end Put;
1324
1325 -----------------
1326 -- Put_Encoded --
1327 -----------------
1328
1329 procedure Put_Encoded (File : File_Type; Char : Character) is
1330 procedure Out_Char (C : Character);
1331 -- Procedure to output one character of an upper half encoded sequence
1332
1333 procedure WC_Out is new Wide_Char_To_Char_Sequence (Out_Char);
1334
1335 --------------
1336 -- Out_Char --
1337 --------------
1338
1339 procedure Out_Char (C : Character) is
1340 begin
1341 Putc (Character'Pos (C), File);
1342 end Out_Char;
1343
1344 -- Start of processing for Put_Encoded
1345
1346 begin
1347 WC_Out (Wide_Character'Val (Character'Pos (Char)), File.WC_Method);
1348 end Put_Encoded;
1349
1350 --------------
1351 -- Put_Line --
1352 --------------
1353
1354 procedure Put_Line
1355 (File : File_Type;
1356 Item : String)
1357 is
1358 Ilen : Natural := Item'Length;
1359 Istart : Natural := Item'First;
1360
1361 begin
1362 FIO.Check_Write_Status (AP (File));
1363
1364 -- If we have bounded lines, or if the file encoding is other than
1365 -- Brackets and the string has at least one upper half character, then
1366 -- output the string character by character.
1367
1368 if File.Line_Length /= 0
1369 or else (File.WC_Method /= WCEM_Brackets
1370 and then Has_Upper_Half_Character (Item))
1371 then
1372 for J in Item'Range loop
1373 Put (File, Item (J));
1374 end loop;
1375
1376 New_Line (File);
1377 return;
1378 end if;
1379
1380 -- Normal case where we do not need to output character by character
1381
1382 -- We setup a single string that has the necessary terminators and
1383 -- then write it with a single call. The reason for doing this is
1384 -- that it gives better behavior for the use of Put_Line in multi-
1385 -- tasking programs, since often the OS will treat the entire put
1386 -- operation as an atomic operation.
1387
1388 -- We only do this if the message is 512 characters or less in length,
1389 -- since otherwise Put_Line would use an unbounded amount of stack
1390 -- space and could cause undetected stack overflow. If we have a
1391 -- longer string, then output the first part separately to avoid this.
1392
1393 if Ilen > 512 then
1394 FIO.Write_Buf (AP (File), Item'Address, size_t (Ilen - 512));
1395 Istart := Istart + Ilen - 512;
1396 Ilen := 512;
1397 end if;
1398
1399 -- Now prepare the string with its terminator
1400
1401 declare
1402 Buffer : String (1 .. Ilen + 2);
1403 Plen : size_t;
1404
1405 begin
1406 Buffer (1 .. Ilen) := Item (Istart .. Item'Last);
1407 Buffer (Ilen + 1) := Character'Val (LM);
1408
1409 if File.Page_Length /= 0
1410 and then File.Line > File.Page_Length
1411 then
1412 Buffer (Ilen + 2) := Character'Val (PM);
1413 Plen := size_t (Ilen) + 2;
1414 File.Line := 1;
1415 File.Page := File.Page + 1;
1416
1417 else
1418 Plen := size_t (Ilen) + 1;
1419 File.Line := File.Line + 1;
1420 end if;
1421
1422 FIO.Write_Buf (AP (File), Buffer'Address, Plen);
1423
1424 File.Col := 1;
1425 end;
1426 end Put_Line;
1427
1428 procedure Put_Line (Item : String) is
1429 begin
1430 Put_Line (Current_Out, Item);
1431 end Put_Line;
1432
1433 ----------
1434 -- Putc --
1435 ----------
1436
1437 procedure Putc (ch : int; File : File_Type) is
1438 begin
1439 if fputc (ch, File.Stream) = EOF then
1440 raise Device_Error;
1441 end if;
1442 end Putc;
1443
1444 ----------
1445 -- Read --
1446 ----------
1447
1448 -- This is the primitive Stream Read routine, used when a Text_IO file
1449 -- is treated directly as a stream using Text_IO.Streams.Stream.
1450
1451 procedure Read
1452 (File : in out Text_AFCB;
1453 Item : out Stream_Element_Array;
1454 Last : out Stream_Element_Offset)
1455 is
1456 Discard_ch : int;
1457 pragma Warnings (Off, Discard_ch);
1458
1459 begin
1460 -- Need to deal with Before_Upper_Half_Character ???
1461
1462 if File.Mode /= FCB.In_File then
1463 raise Mode_Error;
1464 end if;
1465
1466 -- Deal with case where our logical and physical position do not match
1467 -- because of being after an LM or LM-PM sequence when in fact we are
1468 -- logically positioned before it.
1469
1470 if File.Before_LM then
1471
1472 -- If we are before a PM, then it is possible for a stream read
1473 -- to leave us after the LM and before the PM, which is a bit
1474 -- odd. The easiest way to deal with this is to unget the PM,
1475 -- so we are indeed positioned between the characters. This way
1476 -- further stream read operations will work correctly, and the
1477 -- effect on text processing is a little weird, but what can
1478 -- be expected if stream and text input are mixed this way?
1479
1480 if File.Before_LM_PM then
1481 Discard_ch := ungetc (PM, File.Stream);
1482 File.Before_LM_PM := False;
1483 end if;
1484
1485 File.Before_LM := False;
1486
1487 Item (Item'First) := Stream_Element (Character'Pos (ASCII.LF));
1488
1489 if Item'Length = 1 then
1490 Last := Item'Last;
1491
1492 else
1493 Last :=
1494 Item'First +
1495 Stream_Element_Offset
1496 (fread (buffer => Item'Address,
1497 index => size_t (Item'First + 1),
1498 size => 1,
1499 count => Item'Length - 1,
1500 stream => File.Stream));
1501 end if;
1502
1503 return;
1504 end if;
1505
1506 -- Now we do the read. Since this is a text file, it is normally in
1507 -- text mode, but stream data must be read in binary mode, so we
1508 -- temporarily set binary mode for the read, resetting it after.
1509 -- These calls have no effect in a system (like Unix) where there is
1510 -- no distinction between text and binary files.
1511
1512 set_binary_mode (fileno (File.Stream));
1513
1514 Last :=
1515 Item'First +
1516 Stream_Element_Offset
1517 (fread (Item'Address, 1, Item'Length, File.Stream)) - 1;
1518
1519 if Last < Item'Last then
1520 if ferror (File.Stream) /= 0 then
1521 raise Device_Error;
1522 end if;
1523 end if;
1524
1525 set_text_mode (fileno (File.Stream));
1526 end Read;
1527
1528 -----------
1529 -- Reset --
1530 -----------
1531
1532 procedure Reset
1533 (File : in out File_Type;
1534 Mode : File_Mode)
1535 is
1536 begin
1537 -- Don't allow change of mode for current file (RM A.10.2(5))
1538
1539 if (File = Current_In or else
1540 File = Current_Out or else
1541 File = Current_Error)
1542 and then To_FCB (Mode) /= File.Mode
1543 then
1544 raise Mode_Error;
1545 end if;
1546
1547 Terminate_Line (File);
1548 FIO.Reset (AP (File)'Unrestricted_Access, To_FCB (Mode));
1549 File.Page := 1;
1550 File.Line := 1;
1551 File.Col := 1;
1552 File.Line_Length := 0;
1553 File.Page_Length := 0;
1554 File.Before_LM := False;
1555 File.Before_LM_PM := False;
1556 end Reset;
1557
1558 procedure Reset (File : in out File_Type) is
1559 begin
1560 Terminate_Line (File);
1561 FIO.Reset (AP (File)'Unrestricted_Access);
1562 File.Page := 1;
1563 File.Line := 1;
1564 File.Col := 1;
1565 File.Line_Length := 0;
1566 File.Page_Length := 0;
1567 File.Before_LM := False;
1568 File.Before_LM_PM := False;
1569 end Reset;
1570
1571 -------------
1572 -- Set_Col --
1573 -------------
1574
1575 procedure Set_Col
1576 (File : File_Type;
1577 To : Positive_Count)
1578 is
1579 ch : int;
1580
1581 begin
1582 -- Raise Constraint_Error if out of range value. The reason for this
1583 -- explicit test is that we don't want junk values around, even if
1584 -- checks are off in the caller.
1585
1586 if not To'Valid then
1587 raise Constraint_Error;
1588 end if;
1589
1590 FIO.Check_File_Open (AP (File));
1591
1592 -- Output case
1593
1594 if Mode (File) >= Out_File then
1595
1596 -- Error if we attempt to set Col to a value greater than the
1597 -- maximum permissible line length.
1598
1599 if File.Line_Length /= 0 and then To > File.Line_Length then
1600 raise Layout_Error;
1601 end if;
1602
1603 -- If we are behind current position, then go to start of new line
1604
1605 if To < File.Col then
1606 New_Line (File);
1607 end if;
1608
1609 -- Loop to output blanks till we are at the required column
1610
1611 while File.Col < To loop
1612 Put (File, ' ');
1613 end loop;
1614
1615 -- Input case
1616
1617 else
1618 -- If we are logically before a LM, but physically after it, the
1619 -- file position still reflects the position before the LM, so eat
1620 -- it now and adjust the file position appropriately.
1621
1622 if File.Before_LM then
1623 File.Before_LM := False;
1624 File.Before_LM_PM := False;
1625 File.Line := File.Line + 1;
1626 File.Col := 1;
1627 end if;
1628
1629 -- Loop reading characters till we get one at the required Col value
1630
1631 loop
1632 -- Read next character. The reason we have to read ahead is to
1633 -- skip formatting characters, the effect of Set_Col is to set
1634 -- us to a real character with the right Col value, and format
1635 -- characters don't count.
1636
1637 ch := Getc (File);
1638
1639 -- Error if we hit an end of file
1640
1641 if ch = EOF then
1642 raise End_Error;
1643
1644 -- If line mark, eat it and adjust file position
1645
1646 elsif ch = LM then
1647 File.Line := File.Line + 1;
1648 File.Col := 1;
1649
1650 -- If recognized page mark, eat it, and adjust file position
1651
1652 elsif ch = PM and then File.Is_Regular_File then
1653 File.Page := File.Page + 1;
1654 File.Line := 1;
1655 File.Col := 1;
1656
1657 -- Otherwise this is the character we are looking for, so put it
1658 -- back in the input stream (we have not adjusted the file
1659 -- position yet, so everything is set right after this ungetc).
1660
1661 elsif To = File.Col then
1662 Ungetc (ch, File);
1663 return;
1664
1665 -- Keep skipping characters if we are not there yet, updating the
1666 -- file position past the skipped character.
1667
1668 else
1669 File.Col := File.Col + 1;
1670 end if;
1671 end loop;
1672 end if;
1673 end Set_Col;
1674
1675 procedure Set_Col (To : Positive_Count) is
1676 begin
1677 Set_Col (Current_Out, To);
1678 end Set_Col;
1679
1680 ---------------
1681 -- Set_Error --
1682 ---------------
1683
1684 procedure Set_Error (File : File_Type) is
1685 begin
1686 FIO.Check_Write_Status (AP (File));
1687 Current_Err := File;
1688 end Set_Error;
1689
1690 ---------------
1691 -- Set_Input --
1692 ---------------
1693
1694 procedure Set_Input (File : File_Type) is
1695 begin
1696 FIO.Check_Read_Status (AP (File));
1697 Current_In := File;
1698 end Set_Input;
1699
1700 --------------
1701 -- Set_Line --
1702 --------------
1703
1704 procedure Set_Line
1705 (File : File_Type;
1706 To : Positive_Count)
1707 is
1708 begin
1709 -- Raise Constraint_Error if out of range value. The reason for this
1710 -- explicit test is that we don't want junk values around, even if
1711 -- checks are off in the caller.
1712
1713 if not To'Valid then
1714 raise Constraint_Error;
1715 end if;
1716
1717 FIO.Check_File_Open (AP (File));
1718
1719 if To = File.Line then
1720 return;
1721 end if;
1722
1723 if Mode (File) >= Out_File then
1724 if File.Page_Length /= 0 and then To > File.Page_Length then
1725 raise Layout_Error;
1726 end if;
1727
1728 if To < File.Line then
1729 New_Page (File);
1730 end if;
1731
1732 while File.Line < To loop
1733 New_Line (File);
1734 end loop;
1735
1736 else
1737 while To /= File.Line loop
1738 Skip_Line (File);
1739 end loop;
1740 end if;
1741 end Set_Line;
1742
1743 procedure Set_Line (To : Positive_Count) is
1744 begin
1745 Set_Line (Current_Out, To);
1746 end Set_Line;
1747
1748 ---------------------
1749 -- Set_Line_Length --
1750 ---------------------
1751
1752 procedure Set_Line_Length (File : File_Type; To : Count) is
1753 begin
1754 -- Raise Constraint_Error if out of range value. The reason for this
1755 -- explicit test is that we don't want junk values around, even if
1756 -- checks are off in the caller.
1757
1758 if not To'Valid then
1759 raise Constraint_Error;
1760 end if;
1761
1762 FIO.Check_Write_Status (AP (File));
1763 File.Line_Length := To;
1764 end Set_Line_Length;
1765
1766 procedure Set_Line_Length (To : Count) is
1767 begin
1768 Set_Line_Length (Current_Out, To);
1769 end Set_Line_Length;
1770
1771 ----------------
1772 -- Set_Output --
1773 ----------------
1774
1775 procedure Set_Output (File : File_Type) is
1776 begin
1777 FIO.Check_Write_Status (AP (File));
1778 Current_Out := File;
1779 end Set_Output;
1780
1781 ---------------------
1782 -- Set_Page_Length --
1783 ---------------------
1784
1785 procedure Set_Page_Length (File : File_Type; To : Count) is
1786 begin
1787 -- Raise Constraint_Error if out of range value. The reason for this
1788 -- explicit test is that we don't want junk values around, even if
1789 -- checks are off in the caller.
1790
1791 if not To'Valid then
1792 raise Constraint_Error;
1793 end if;
1794
1795 FIO.Check_Write_Status (AP (File));
1796 File.Page_Length := To;
1797 end Set_Page_Length;
1798
1799 procedure Set_Page_Length (To : Count) is
1800 begin
1801 Set_Page_Length (Current_Out, To);
1802 end Set_Page_Length;
1803
1804 --------------
1805 -- Set_WCEM --
1806 --------------
1807
1808 procedure Set_WCEM (File : in out File_Type) is
1809 Start : Natural;
1810 Stop : Natural;
1811
1812 begin
1813 File.WC_Method := WCEM_Brackets;
1814 FIO.Form_Parameter (File.Form.all, "wcem", Start, Stop);
1815
1816 if Start = 0 then
1817 File.WC_Method := WCEM_Brackets;
1818
1819 else
1820 if Stop = Start then
1821 for J in WC_Encoding_Letters'Range loop
1822 if File.Form (Start) = WC_Encoding_Letters (J) then
1823 File.WC_Method := J;
1824 return;
1825 end if;
1826 end loop;
1827 end if;
1828
1829 Close (File);
1830 raise Use_Error with "invalid WCEM form parameter";
1831 end if;
1832 end Set_WCEM;
1833
1834 ---------------
1835 -- Skip_Line --
1836 ---------------
1837
1838 procedure Skip_Line
1839 (File : File_Type;
1840 Spacing : Positive_Count := 1)
1841 is
1842 ch : int;
1843
1844 begin
1845 -- Raise Constraint_Error if out of range value. The reason for this
1846 -- explicit test is that we don't want junk values around, even if
1847 -- checks are off in the caller.
1848
1849 if not Spacing'Valid then
1850 raise Constraint_Error;
1851 end if;
1852
1853 FIO.Check_Read_Status (AP (File));
1854
1855 for L in 1 .. Spacing loop
1856 if File.Before_LM then
1857 File.Before_LM := False;
1858
1859 -- Note that if File.Before_LM_PM is currently set, we also have
1860 -- to reset it (because it makes sense for Before_LM_PM to be set
1861 -- only when Before_LM is also set). This is done later on in this
1862 -- subprogram, as soon as Before_LM_PM has been taken into account
1863 -- for the purpose of page and line counts.
1864
1865 else
1866 ch := Getc (File);
1867
1868 -- If at end of file now, then immediately raise End_Error. Note
1869 -- that we can never be positioned between a line mark and a page
1870 -- mark, so if we are at the end of file, we cannot logically be
1871 -- before the implicit page mark that is at the end of the file.
1872
1873 -- For the same reason, we do not need an explicit check for a
1874 -- page mark. If there is a FF in the middle of a line, the file
1875 -- is not in canonical format and we do not care about the page
1876 -- numbers for files other than ones in canonical format.
1877
1878 if ch = EOF then
1879 raise End_Error;
1880 end if;
1881
1882 -- If not at end of file, then loop till we get to an LM or EOF.
1883 -- The latter case happens only in non-canonical files where the
1884 -- last line is not terminated by LM, but we don't want to blow
1885 -- up for such files, so we assume an implicit LM in this case.
1886
1887 loop
1888 exit when ch = LM or else ch = EOF;
1889 ch := Getc (File);
1890 end loop;
1891 end if;
1892
1893 -- We have got past a line mark, now, for a regular file only,
1894 -- see if a page mark immediately follows this line mark and
1895 -- if so, skip past the page mark as well. We do not do this
1896 -- for non-regular files, since it would cause an undesirable
1897 -- wait for an additional character.
1898
1899 File.Col := 1;
1900 File.Line := File.Line + 1;
1901
1902 if File.Before_LM_PM then
1903 File.Page := File.Page + 1;
1904 File.Line := 1;
1905 File.Before_LM_PM := False;
1906
1907 elsif File.Is_Regular_File then
1908 ch := Getc (File);
1909
1910 -- Page mark can be explicit, or implied at the end of the file
1911
1912 if (ch = PM or else ch = EOF)
1913 and then File.Is_Regular_File
1914 then
1915 File.Page := File.Page + 1;
1916 File.Line := 1;
1917 else
1918 Ungetc (ch, File);
1919 end if;
1920 end if;
1921 end loop;
1922
1923 File.Before_Upper_Half_Character := False;
1924 end Skip_Line;
1925
1926 procedure Skip_Line (Spacing : Positive_Count := 1) is
1927 begin
1928 Skip_Line (Current_In, Spacing);
1929 end Skip_Line;
1930
1931 ---------------
1932 -- Skip_Page --
1933 ---------------
1934
1935 procedure Skip_Page (File : File_Type) is
1936 ch : int;
1937
1938 begin
1939 FIO.Check_Read_Status (AP (File));
1940
1941 -- If at page mark already, just skip it
1942
1943 if File.Before_LM_PM then
1944 File.Before_LM := False;
1945 File.Before_LM_PM := False;
1946 File.Page := File.Page + 1;
1947 File.Line := 1;
1948 File.Col := 1;
1949 return;
1950 end if;
1951
1952 -- This is a bit tricky, if we are logically before an LM then
1953 -- it is not an error if we are at an end of file now, since we
1954 -- are not really at it.
1955
1956 if File.Before_LM then
1957 File.Before_LM := False;
1958 File.Before_LM_PM := False;
1959 ch := Getc (File);
1960
1961 -- Otherwise we do raise End_Error if we are at the end of file now
1962
1963 else
1964 ch := Getc (File);
1965
1966 if ch = EOF then
1967 raise End_Error;
1968 end if;
1969 end if;
1970
1971 -- Now we can just rumble along to the next page mark, or to the
1972 -- end of file, if that comes first. The latter case happens when
1973 -- the page mark is implied at the end of file.
1974
1975 loop
1976 exit when ch = EOF
1977 or else (ch = PM and then File.Is_Regular_File);
1978 ch := Getc (File);
1979 end loop;
1980
1981 File.Page := File.Page + 1;
1982 File.Line := 1;
1983 File.Col := 1;
1984 File.Before_Upper_Half_Character := False;
1985 end Skip_Page;
1986
1987 procedure Skip_Page is
1988 begin
1989 Skip_Page (Current_In);
1990 end Skip_Page;
1991
1992 --------------------
1993 -- Standard_Error --
1994 --------------------
1995
1996 function Standard_Error return File_Type is
1997 begin
1998 return Standard_Err;
1999 end Standard_Error;
2000
2001 function Standard_Error return File_Access is
2002 begin
2003 return Standard_Err'Access;
2004 end Standard_Error;
2005
2006 --------------------
2007 -- Standard_Input --
2008 --------------------
2009
2010 function Standard_Input return File_Type is
2011 begin
2012 return Standard_In;
2013 end Standard_Input;
2014
2015 function Standard_Input return File_Access is
2016 begin
2017 return Standard_In'Access;
2018 end Standard_Input;
2019
2020 ---------------------
2021 -- Standard_Output --
2022 ---------------------
2023
2024 function Standard_Output return File_Type is
2025 begin
2026 return Standard_Out;
2027 end Standard_Output;
2028
2029 function Standard_Output return File_Access is
2030 begin
2031 return Standard_Out'Access;
2032 end Standard_Output;
2033
2034 --------------------
2035 -- Terminate_Line --
2036 --------------------
2037
2038 procedure Terminate_Line (File : File_Type) is
2039 begin
2040 FIO.Check_File_Open (AP (File));
2041
2042 -- For file other than In_File, test for needing to terminate last line
2043
2044 if Mode (File) /= In_File then
2045
2046 -- If not at start of line definition need new line
2047
2048 if File.Col /= 1 then
2049 New_Line (File);
2050
2051 -- For files other than standard error and standard output, we
2052 -- make sure that an empty file has a single line feed, so that
2053 -- it is properly formatted. We avoid this for the standard files
2054 -- because it is too much of a nuisance to have these odd line
2055 -- feeds when nothing has been written to the file.
2056
2057 -- We also avoid this for files opened in append mode, in
2058 -- accordance with (RM A.8.2(10))
2059
2060 elsif (File /= Standard_Err and then File /= Standard_Out)
2061 and then (File.Line = 1 and then File.Page = 1)
2062 and then Mode (File) = Out_File
2063 then
2064 New_Line (File);
2065 end if;
2066 end if;
2067 end Terminate_Line;
2068
2069 ------------
2070 -- Ungetc --
2071 ------------
2072
2073 procedure Ungetc (ch : int; File : File_Type) is
2074 begin
2075 if ch /= EOF then
2076 if ungetc (ch, File.Stream) = EOF then
2077 raise Device_Error;
2078 end if;
2079 end if;
2080 end Ungetc;
2081
2082 -----------
2083 -- Write --
2084 -----------
2085
2086 -- This is the primitive Stream Write routine, used when a Text_IO file
2087 -- is treated directly as a stream using Text_IO.Streams.Stream.
2088
2089 procedure Write
2090 (File : in out Text_AFCB;
2091 Item : Stream_Element_Array)
2092 is
2093 pragma Warnings (Off, File);
2094 -- Because in this implementation we don't need IN OUT, we only read
2095
2096 function Has_Translated_Characters return Boolean;
2097 -- return True if Item array contains a character which will be
2098 -- translated under the text file mode. There is only one such
2099 -- character under DOS based systems which is character 10.
2100
2101 text_translation_required : Boolean;
2102 for text_translation_required'Size use Character'Size;
2103 pragma Import (C, text_translation_required,
2104 "__gnat_text_translation_required");
2105
2106 Siz : constant size_t := Item'Length;
2107
2108 -------------------------------
2109 -- Has_Translated_Characters --
2110 -------------------------------
2111
2112 function Has_Translated_Characters return Boolean is
2113 begin
2114 for K in Item'Range loop
2115 if Item (K) = 10 then
2116 return True;
2117 end if;
2118 end loop;
2119 return False;
2120 end Has_Translated_Characters;
2121
2122 Needs_Binary_Write : constant Boolean :=
2123 text_translation_required and then Has_Translated_Characters;
2124
2125 -- Start of processing for Write
2126
2127 begin
2128 if File.Mode = FCB.In_File then
2129 raise Mode_Error;
2130 end if;
2131
2132 -- Now we do the write. Since this is a text file, it is normally in
2133 -- text mode, but stream data must be written in binary mode, so we
2134 -- temporarily set binary mode for the write, resetting it after. This
2135 -- is done only if needed (i.e. there is some characters in Item which
2136 -- needs to be written using the binary mode).
2137 -- These calls have no effect in a system (like Unix) where there is
2138 -- no distinction between text and binary files.
2139
2140 -- Since the character translation is done at the time the buffer is
2141 -- written (this is true under Windows) we first flush current buffer
2142 -- with text mode if needed.
2143
2144 if Needs_Binary_Write then
2145 if fflush (File.Stream) = -1 then
2146 raise Device_Error;
2147 end if;
2148
2149 set_binary_mode (fileno (File.Stream));
2150 end if;
2151
2152 if fwrite (Item'Address, 1, Siz, File.Stream) /= Siz then
2153 raise Device_Error;
2154 end if;
2155
2156 -- At this point we need to flush the buffer using the binary mode then
2157 -- we reset to text mode.
2158
2159 if Needs_Binary_Write then
2160 if fflush (File.Stream) = -1 then
2161 raise Device_Error;
2162 end if;
2163
2164 set_text_mode (fileno (File.Stream));
2165 end if;
2166 end Write;
2167
2168 begin
2169 -- Initialize Standard Files
2170
2171 for J in WC_Encoding_Method loop
2172 if WC_Encoding = WC_Encoding_Letters (J) then
2173 Default_WCEM := J;
2174 end if;
2175 end loop;
2176
2177 Initialize_Standard_Files;
2178
2179 FIO.Chain_File (AP (Standard_In));
2180 FIO.Chain_File (AP (Standard_Out));
2181 FIO.Chain_File (AP (Standard_Err));
2182
2183 end Ada.Text_IO;