1 ------------------------------------------------------------------------------
3 -- GNAT RUNTIME COMPONENTS --
5 -- A D A . S T R E A M S . S T R E A M _ I O --
10 -- Copyright (C) 1992-2001, Free Software Foundation, Inc. --
12 -- GNAT is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNAT; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNAT was originally developed by the GNAT team at New York University. --
31 -- It is now maintained by Ada Core Technologies Inc (http://www.gnat.com). --
33 ------------------------------------------------------------------------------
35 with Interfaces.C_Streams; use Interfaces.C_Streams;
36 with System; use System;
38 with System.Soft_Links;
39 with Unchecked_Conversion;
40 with Unchecked_Deallocation;
42 package body Ada.Streams.Stream_IO is
44 package FIO renames System.File_IO;
45 package SSL renames System.Soft_Links;
47 subtype AP is FCB.AFCB_Ptr;
49 function To_FCB is new Unchecked_Conversion (File_Mode, FCB.File_Mode);
50 function To_SIO is new Unchecked_Conversion (FCB.File_Mode, File_Mode);
51 use type FCB.File_Mode;
52 use type FCB.Shared_Status_Type;
54 -----------------------
55 -- Local Subprograms --
56 -----------------------
58 procedure Set_Position (File : in File_Type);
59 -- Sets file position pointer according to value of current index
65 function AFCB_Allocate (Control_Block : Stream_AFCB) return FCB.AFCB_Ptr is
66 pragma Warnings (Off, Control_Block);
69 return new Stream_AFCB;
76 -- No special processing required for closing Stream_IO file
78 procedure AFCB_Close (File : access Stream_AFCB) is
79 pragma Warnings (Off, File);
89 procedure AFCB_Free (File : access Stream_AFCB) is
90 type FCB_Ptr is access all Stream_AFCB;
91 FT : FCB_Ptr := FCB_Ptr (File);
93 procedure Free is new Unchecked_Deallocation (Stream_AFCB, FCB_Ptr);
103 procedure Close (File : in out File_Type) is
105 FIO.Close (AP (File));
113 (File : in out File_Type;
114 Mode : in File_Mode := Out_File;
115 Name : in String := "";
116 Form : in String := "")
118 File_Control_Block : Stream_AFCB;
121 FIO.Open (File_Ptr => AP (File),
122 Dummy_FCB => File_Control_Block,
123 Mode => To_FCB (Mode),
129 File.Last_Op := Op_Write;
136 procedure Delete (File : in out File_Type) is
138 FIO.Delete (AP (File));
145 function End_Of_File (File : in File_Type) return Boolean is
147 FIO.Check_Read_Status (AP (File));
148 return Count (File.Index) > Size (File);
155 procedure Flush (File : File_Type) is
157 FIO.Flush (AP (File));
164 function Form (File : in File_Type) return String is
166 return FIO.Form (AP (File));
173 function Index (File : in File_Type) return Positive_Count is
175 FIO.Check_File_Open (AP (File));
176 return Count (File.Index);
183 function Is_Open (File : in File_Type) return Boolean is
185 return FIO.Is_Open (AP (File));
192 function Mode (File : in File_Type) return File_Mode is
194 return To_SIO (FIO.Mode (AP (File)));
201 function Name (File : in File_Type) return String is
203 return FIO.Name (AP (File));
211 (File : in out File_Type;
214 Form : in String := "")
216 File_Control_Block : Stream_AFCB;
219 FIO.Open (File_Ptr => AP (File),
220 Dummy_FCB => File_Control_Block,
221 Mode => To_FCB (Mode),
228 -- Ensure that the stream index is set properly (e.g., for Append_File)
232 File.Last_Op := Op_Read;
240 (File : in File_Type;
241 Item : out Stream_Element_Array;
242 Last : out Stream_Element_Offset;
243 From : in Positive_Count)
246 Set_Index (File, From);
247 Read (File, Item, Last);
251 (File : in File_Type;
252 Item : out Stream_Element_Array;
253 Last : out Stream_Element_Offset)
258 FIO.Check_Read_Status (AP (File));
260 -- If last operation was not a read, or if in file sharing mode,
261 -- then reset the physical pointer of the file to match the index
262 -- We lock out task access over the two operations in this case.
264 if File.Last_Op /= Op_Read
265 or else File.Shared_Status = FCB.Yes
267 Locked_Processing : begin
270 FIO.Read_Buf (AP (File), Item'Address, Item'Length, Nread);
277 end Locked_Processing;
280 FIO.Read_Buf (AP (File), Item'Address, Item'Length, Nread);
283 File.Index := File.Index + Count (Nread);
284 Last := Item'First + Stream_Element_Offset (Nread) - 1;
285 File.Last_Op := Op_Read;
288 -- This version of Read is the primitive operation on the underlying
289 -- Stream type, used when a Stream_IO file is treated as a Stream
292 (File : in out Stream_AFCB;
293 Item : out Ada.Streams.Stream_Element_Array;
294 Last : out Ada.Streams.Stream_Element_Offset)
297 Read (File'Unchecked_Access, Item, Last);
304 procedure Reset (File : in out File_Type; Mode : in File_Mode) is
306 FIO.Check_File_Open (AP (File));
308 -- Reset file index to start of file for read/write cases. For
309 -- the append case, the Set_Mode call repositions the index.
312 Set_Mode (File, Mode);
315 procedure Reset (File : in out File_Type) is
317 Reset (File, To_SIO (File.Mode));
324 procedure Set_Index (File : in File_Type; To : in Positive_Count) is
326 FIO.Check_File_Open (AP (File));
327 File.Index := Count (To);
328 File.Last_Op := Op_Other;
335 procedure Set_Mode (File : in out File_Type; Mode : in File_Mode) is
337 FIO.Check_File_Open (AP (File));
339 -- If we are switching from read to write, or vice versa, and
340 -- we are not already open in update mode, then reopen in update
341 -- mode now. Note that we can use Inout_File as the mode for the
342 -- call since File_IO handles all modes for all file types.
344 if ((File.Mode = FCB.In_File) /= (Mode = In_File))
345 and then not File.Update_Mode
347 FIO.Reset (AP (File), FCB.Inout_File);
348 File.Update_Mode := True;
351 -- Set required mode and position to end of file if append mode
353 File.Mode := To_FCB (Mode);
354 FIO.Append_Set (AP (File));
356 if File.Mode = FCB.Append_File then
357 File.Index := Count (ftell (File.Stream)) + 1;
360 File.Last_Op := Op_Other;
367 procedure Set_Position (File : in File_Type) is
369 if fseek (File.Stream, long (File.Index) - 1, SEEK_SET) /= 0 then
378 function Size (File : in File_Type) return Count is
380 FIO.Check_File_Open (AP (File));
382 if File.File_Size = -1 then
383 File.Last_Op := Op_Other;
385 if fseek (File.Stream, 0, SEEK_END) /= 0 then
389 File.File_Size := Stream_Element_Offset (ftell (File.Stream));
392 return Count (File.File_Size);
399 function Stream (File : in File_Type) return Stream_Access is
401 FIO.Check_File_Open (AP (File));
402 return Stream_Access (File);
410 (File : in File_Type;
411 Item : in Stream_Element_Array;
412 To : in Positive_Count)
415 Set_Index (File, To);
419 procedure Write (File : in File_Type; Item : in Stream_Element_Array) is
421 FIO.Check_Write_Status (AP (File));
423 -- If last operation was not a write, or if in file sharing mode,
424 -- then reset the physical pointer of the file to match the index
425 -- We lock out task access over the two operations in this case.
427 if File.Last_Op /= Op_Write
428 or else File.Shared_Status = FCB.Yes
430 Locked_Processing : begin
433 FIO.Write_Buf (AP (File), Item'Address, Item'Length);
440 end Locked_Processing;
443 FIO.Write_Buf (AP (File), Item'Address, Item'Length);
446 File.Index := File.Index + Item'Length;
447 File.Last_Op := Op_Write;
448 File.File_Size := -1;
451 -- This version of Write is the primitive operation on the underlying
452 -- Stream type, used when a Stream_IO file is treated as a Stream
455 (File : in out Stream_AFCB;
456 Item : in Ada.Streams.Stream_Element_Array)
459 Write (File'Unchecked_Access, Item);
462 end Ada.Streams.Stream_IO;