File : s-stratt.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT RUN-TIME COMPONENTS --
4 -- --
5 -- S Y S T E M . S T R E A M _ A T T R I B U T E S --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2013, 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 -- This package contains the implementations of the stream attributes for
33 -- elementary types. These are the subprograms that are directly accessed
34 -- by occurrences of the stream attributes where the type is elementary.
35
36 -- We only provide the subprograms for the standard base types. For user
37 -- defined types, the subprogram for the corresponding root type is called
38 -- with an appropriate conversion.
39
40 with System;
41 with System.Unsigned_Types;
42 with Ada.Streams;
43
44 package System.Stream_Attributes is
45 pragma Preelaborate;
46
47 pragma Suppress (Accessibility_Check, Stream_Attributes);
48 -- No need to check accessibility on arguments of subprograms
49
50 package UST renames System.Unsigned_Types;
51
52 subtype RST is Ada.Streams.Root_Stream_Type'Class;
53
54 subtype SEC is Ada.Streams.Stream_Element_Count;
55
56 -- Enumeration types are usually transferred using the routine for the
57 -- corresponding integer. The exception is that special routines are
58 -- provided for Boolean and the character types, in case the protocol
59 -- in use provides specially for these types.
60
61 -- Access types use either a thin pointer (single address) or fat pointer
62 -- (double address) form. The following types are used to hold access
63 -- values using unchecked conversions.
64
65 type Thin_Pointer is record
66 P1 : System.Address;
67 end record;
68
69 type Fat_Pointer is record
70 P1 : System.Address;
71 P2 : System.Address;
72 end record;
73
74 ------------------------------------
75 -- Treatment of enumeration types --
76 ------------------------------------
77
78 -- In this interface, there are no specific routines for general input
79 -- or output of enumeration types. Generally, enumeration types whose
80 -- representation is unsigned (no negative representation values) are
81 -- treated as unsigned integers, and enumeration types that do have
82 -- negative representation values are treated as signed integers.
83
84 -- An exception is that there are specialized routines for Boolean,
85 -- Character, and Wide_Character types, but these specialized routines
86 -- are used only if the type in question has a standard representation.
87 -- For the case of a non-standard representation (one where the size of
88 -- the first subtype is specified, or where an enumeration representation
89 -- clause is given, these three types are treated like any other cases
90 -- of enumeration types, as described above.
91
92 ---------------------
93 -- Input Functions --
94 ---------------------
95
96 -- Functions for S'Input attribute. These functions are also used for
97 -- S'Read, with the obvious transformation, since the input operation
98 -- is the same for all elementary types (no bounds or discriminants
99 -- are involved).
100
101 function I_AD (Stream : not null access RST) return Fat_Pointer;
102 function I_AS (Stream : not null access RST) return Thin_Pointer;
103 function I_B (Stream : not null access RST) return Boolean;
104 function I_C (Stream : not null access RST) return Character;
105 function I_F (Stream : not null access RST) return Float;
106 function I_I (Stream : not null access RST) return Integer;
107 function I_LF (Stream : not null access RST) return Long_Float;
108 function I_LI (Stream : not null access RST) return Long_Integer;
109 function I_LLF (Stream : not null access RST) return Long_Long_Float;
110 function I_LLI (Stream : not null access RST) return Long_Long_Integer;
111 function I_LLU (Stream : not null access RST) return UST.Long_Long_Unsigned;
112 function I_LU (Stream : not null access RST) return UST.Long_Unsigned;
113 function I_SF (Stream : not null access RST) return Short_Float;
114 function I_SI (Stream : not null access RST) return Short_Integer;
115 function I_SSI (Stream : not null access RST) return Short_Short_Integer;
116 function I_SSU (Stream : not null access RST) return
117 UST.Short_Short_Unsigned;
118 function I_SU (Stream : not null access RST) return UST.Short_Unsigned;
119 function I_U (Stream : not null access RST) return UST.Unsigned;
120 function I_WC (Stream : not null access RST) return Wide_Character;
121 function I_WWC (Stream : not null access RST) return Wide_Wide_Character;
122
123 -----------------------
124 -- Output Procedures --
125 -----------------------
126
127 -- Procedures for S'Write attribute. These procedures are also used for
128 -- 'Output, since for elementary types there is no difference between
129 -- 'Write and 'Output because there are no discriminants or bounds to
130 -- be written.
131
132 procedure W_AD (Stream : not null access RST; Item : Fat_Pointer);
133 procedure W_AS (Stream : not null access RST; Item : Thin_Pointer);
134 procedure W_B (Stream : not null access RST; Item : Boolean);
135 procedure W_C (Stream : not null access RST; Item : Character);
136 procedure W_F (Stream : not null access RST; Item : Float);
137 procedure W_I (Stream : not null access RST; Item : Integer);
138 procedure W_LF (Stream : not null access RST; Item : Long_Float);
139 procedure W_LI (Stream : not null access RST; Item : Long_Integer);
140 procedure W_LLF (Stream : not null access RST; Item : Long_Long_Float);
141 procedure W_LLI (Stream : not null access RST; Item : Long_Long_Integer);
142 procedure W_LLU (Stream : not null access RST; Item :
143 UST.Long_Long_Unsigned);
144 procedure W_LU (Stream : not null access RST; Item : UST.Long_Unsigned);
145 procedure W_SF (Stream : not null access RST; Item : Short_Float);
146 procedure W_SI (Stream : not null access RST; Item : Short_Integer);
147 procedure W_SSI (Stream : not null access RST; Item : Short_Short_Integer);
148 procedure W_SSU (Stream : not null access RST; Item :
149 UST.Short_Short_Unsigned);
150 procedure W_SU (Stream : not null access RST; Item : UST.Short_Unsigned);
151 procedure W_U (Stream : not null access RST; Item : UST.Unsigned);
152 procedure W_WC (Stream : not null access RST; Item : Wide_Character);
153 procedure W_WWC (Stream : not null access RST; Item : Wide_Wide_Character);
154
155 function Block_IO_OK return Boolean;
156 -- Package System.Stream_Attributes has several bodies - the default one
157 -- distributed with GNAT, and s-stratt-xdr.adb, which is based on the XDR
158 -- standard. Both bodies share the same spec. The role of this function is
159 -- to indicate whether the current version of System.Stream_Attributes
160 -- supports block IO. See System.Strings.Stream_Ops (s-ststop) for details.
161
162 private
163 pragma Inline (I_AD);
164 pragma Inline (I_AS);
165 pragma Inline (I_B);
166 pragma Inline (I_C);
167 pragma Inline (I_F);
168 pragma Inline (I_I);
169 pragma Inline (I_LF);
170 pragma Inline (I_LI);
171 pragma Inline (I_LLF);
172 pragma Inline (I_LLI);
173 pragma Inline (I_LLU);
174 pragma Inline (I_LU);
175 pragma Inline (I_SF);
176 pragma Inline (I_SI);
177 pragma Inline (I_SSI);
178 pragma Inline (I_SSU);
179 pragma Inline (I_SU);
180 pragma Inline (I_U);
181 pragma Inline (I_WC);
182 pragma Inline (I_WWC);
183
184 pragma Inline (W_AD);
185 pragma Inline (W_AS);
186 pragma Inline (W_B);
187 pragma Inline (W_C);
188 pragma Inline (W_F);
189 pragma Inline (W_I);
190 pragma Inline (W_LF);
191 pragma Inline (W_LI);
192 pragma Inline (W_LLF);
193 pragma Inline (W_LLI);
194 pragma Inline (W_LLU);
195 pragma Inline (W_LU);
196 pragma Inline (W_SF);
197 pragma Inline (W_SI);
198 pragma Inline (W_SSI);
199 pragma Inline (W_SSU);
200 pragma Inline (W_SU);
201 pragma Inline (W_U);
202 pragma Inline (W_WC);
203 pragma Inline (W_WWC);
204
205 pragma Inline (Block_IO_OK);
206
207 end System.Stream_Attributes;