1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
|
------------------------------------------------------------------------------
-- --
-- GNAT RUNTIME COMPONENTS --
-- --
-- A D A . S E Q U E N T I A L _ I O --
-- --
-- B o d y --
-- --
-- Copyright (C) 1992-1999, Free Software Foundation, Inc. --
-- --
-- GNAT is free software; you can redistribute it and/or modify it under --
-- terms of the GNU General Public License as published by the Free Soft- --
-- ware Foundation; either version 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 --
-- 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 --
-- 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. --
-- --
-- GNAT was originally developed by the GNAT team at New York University. --
-- Extensive contributions were provided by Ada Core Technologies Inc. --
-- --
------------------------------------------------------------------------------
-- This is the generic template for Sequential_IO, i.e. the code that gets
-- duplicated. We absolutely minimize this code by either calling routines
-- in System.File_IO (for common file functions), or in System.Sequential_IO
-- (for specialized Sequential_IO functions)
with Interfaces.C_Streams; use Interfaces.C_Streams;
with System;
with System.File_Control_Block;
with System.File_IO;
with System.Storage_Elements;
with Unchecked_Conversion;
package body Ada.Sequential_IO is
package FIO renames System.File_IO;
package FCB renames System.File_Control_Block;
package SIO renames System.Sequential_IO;
package SSE renames System.Storage_Elements;
SU : constant := System.Storage_Unit;
subtype AP is FCB.AFCB_Ptr;
subtype FP is SIO.File_Type;
function To_FCB is new Unchecked_Conversion (File_Mode, FCB.File_Mode);
function To_SIO is new Unchecked_Conversion (FCB.File_Mode, File_Mode);
-----------
-- Close --
-----------
procedure Close (File : in out File_Type) is
begin
FIO.Close (AP (File));
end Close;
------------
-- Create --
------------
procedure Create
(File : in out File_Type;
Mode : in File_Mode := Out_File;
Name : in String := "";
Form : in String := "")
is
begin
SIO.Create (FP (File), To_FCB (Mode), Name, Form);
end Create;
------------
-- Delete --
------------
procedure Delete (File : in out File_Type) is
begin
FIO.Delete (AP (File));
end Delete;
-----------------
-- End_Of_File --
-----------------
function End_Of_File (File : in File_Type) return Boolean is
begin
return FIO.End_Of_File (AP (File));
end End_Of_File;
----------
-- Form --
----------
function Form (File : in File_Type) return String is
begin
return FIO.Form (AP (File));
end Form;
-------------
-- Is_Open --
-------------
function Is_Open (File : in File_Type) return Boolean is
begin
return FIO.Is_Open (AP (File));
end Is_Open;
----------
-- Mode --
----------
function Mode (File : in File_Type) return File_Mode is
begin
return To_SIO (FIO.Mode (AP (File)));
end Mode;
----------
-- Name --
----------
function Name (File : in File_Type) return String is
begin
return FIO.Name (AP (File));
end Name;
----------
-- Open --
----------
procedure Open
(File : in out File_Type;
Mode : in File_Mode;
Name : in String;
Form : in String := "")
is
begin
SIO.Open (FP (File), To_FCB (Mode), Name, Form);
end Open;
----------
-- Read --
----------
procedure Read (File : in File_Type; Item : out Element_Type) is
Siz : constant size_t := (Item'Size + SU - 1) / SU;
Rsiz : size_t;
begin
FIO.Check_Read_Status (AP (File));
-- For non-definite type or type with discriminants, read size and
-- raise Program_Error if it is larger than the size of the item.
if not Element_Type'Definite
or else Element_Type'Has_Discriminants
then
FIO.Read_Buf
(AP (File), Rsiz'Address, size_t'Size / System.Storage_Unit);
-- For a type with discriminants, we have to read into a temporary
-- buffer if Item is constrained, to check that the discriminants
-- are correct.
pragma Extensions_Allowed (On);
-- Needed to allow Constrained reference here
if Element_Type'Has_Discriminants
and then Item'Constrained
then
declare
RsizS : constant SSE.Storage_Offset :=
SSE.Storage_Offset (Rsiz - 1);
subtype SA is SSE.Storage_Array (0 .. RsizS);
type SAP is access all SA;
type ItemP is access all Element_Type;
pragma Warnings (Off);
-- We have to turn warnings off for this function, because
-- it gets analyzed for all types, including ones which
-- can't possibly come this way, and for which the size
-- of the access types differs.
function To_ItemP is new Unchecked_Conversion (SAP, ItemP);
pragma Warnings (On);
Buffer : aliased SA;
pragma Unsuppress (Discriminant_Check);
begin
FIO.Read_Buf (AP (File), Buffer'Address, Rsiz);
Item := To_ItemP (Buffer'Access).all;
return;
end;
end if;
-- In the case of a non-definite type, make sure the length is OK.
-- We can't do this in the variant record case, because the size is
-- based on the current discriminant, so may be apparently wrong.
if not Element_Type'Has_Discriminants and then Rsiz > Siz then
raise Program_Error;
end if;
FIO.Read_Buf (AP (File), Item'Address, Rsiz);
-- For definite type without discriminants, use actual size of item
else
FIO.Read_Buf (AP (File), Item'Address, Siz);
end if;
end Read;
-----------
-- Reset --
-----------
procedure Reset (File : in out File_Type; Mode : in File_Mode) is
begin
FIO.Reset (AP (File), To_FCB (Mode));
end Reset;
procedure Reset (File : in out File_Type) is
begin
FIO.Reset (AP (File));
end Reset;
-----------
-- Write --
-----------
procedure Write (File : in File_Type; Item : in Element_Type) is
Siz : constant size_t := (Item'Size + SU - 1) / SU;
begin
FIO.Check_Write_Status (AP (File));
-- For non-definite types or types with discriminants, write the size
if not Element_Type'Definite
or else Element_Type'Has_Discriminants
then
FIO.Write_Buf
(AP (File), Siz'Address, size_t'Size / System.Storage_Unit);
end if;
FIO.Write_Buf (AP (File), Item'Address, Siz);
end Write;
end Ada.Sequential_IO;
|
