1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--             A D A . W I D E _ T E X T _ I O . F I X E D _ I O            --
6--                                                                          --
7--                                 B o d y                                  --
8--                                                                          --
9--          Copyright (C) 1992-2021, 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-- As a special exception under Section 7 of GPL version 3, you are granted --
19-- additional permissions described in the GCC Runtime Library Exception,   --
20-- version 3.1, as published by the Free Software Foundation.               --
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
32with Interfaces;
33with Ada.Wide_Text_IO.Fixed_Aux;
34with Ada.Wide_Text_IO.Float_Aux;
35with System.Img_Fixed_32; use System.Img_Fixed_32;
36with System.Img_Fixed_64; use System.Img_Fixed_64;
37with System.Img_LFlt;     use System.Img_LFlt;
38with System.Val_Fixed_32; use System.Val_Fixed_32;
39with System.Val_Fixed_64; use System.Val_Fixed_64;
40with System.Val_LFlt;     use System.Val_LFlt;
41with System.WCh_Con;      use System.WCh_Con;
42with System.WCh_WtS;      use System.WCh_WtS;
43
44package body Ada.Wide_Text_IO.Fixed_IO is
45
46   --  Note: we still use the floating-point I/O routines for types whose small
47   --  is not the ratio of two sufficiently small integers. This will result in
48   --  inaccuracies for fixed point types that require more precision than is
49   --  available in Long_Float.
50
51   subtype Int32 is Interfaces.Integer_32; use type Int32;
52   subtype Int64 is Interfaces.Integer_64; use type Int64;
53
54   package Aux32 is new
55     Ada.Wide_Text_IO.Fixed_Aux (Int32, Scan_Fixed32, Set_Image_Fixed32);
56
57   package Aux64 is new
58     Ada.Wide_Text_IO.Fixed_Aux (Int64, Scan_Fixed64, Set_Image_Fixed64);
59
60   package Aux_Long_Float is new
61     Ada.Wide_Text_IO.Float_Aux
62       (Long_Float, Scan_Long_Float, Set_Image_Long_Float);
63
64   --  Throughout this generic body, we distinguish between the case where type
65   --  Int32 is OK and where type Int64 is OK. These boolean constants are used
66   --  to test for this, such that only code for the relevant case is included
67   --  in the instance; that's why the computation of their value must be fully
68   --  static (although it is not a static expressions in the RM sense).
69
70   OK_Get_32 : constant Boolean :=
71     Num'Base'Object_Size <= 32
72       and then
73         ((Num'Small_Numerator = 1 and then Num'Small_Denominator <= 2**31)
74           or else
75          (Num'Small_Denominator = 1 and then Num'Small_Numerator <= 2**31)
76           or else
77          (Num'Small_Numerator <= 2**27
78            and then Num'Small_Denominator <= 2**27));
79   --  These conditions are derived from the prerequisites of System.Value_F
80
81   OK_Put_32 : constant Boolean :=
82     Num'Base'Object_Size <= 32
83       and then
84         ((Num'Small_Numerator = 1 and then Num'Small_Denominator <= 2**31)
85           or else
86          (Num'Small_Denominator = 1 and then Num'Small_Numerator <= 2**31)
87           or else
88          (Num'Small_Numerator < Num'Small_Denominator
89            and then Num'Small_Denominator <= 2**27)
90           or else
91          (Num'Small_Denominator < Num'Small_Numerator
92            and then Num'Small_Numerator <= 2**25));
93   --  These conditions are derived from the prerequisites of System.Image_F
94
95   OK_Get_64 : constant Boolean :=
96     Num'Base'Object_Size <= 64
97       and then
98         ((Num'Small_Numerator = 1 and then Num'Small_Denominator <= 2**63)
99           or else
100          (Num'Small_Denominator = 1 and then Num'Small_Numerator <= 2**63)
101           or else
102          (Num'Small_Numerator <= 2**59
103            and then Num'Small_Denominator <= 2**59));
104   --  These conditions are derived from the prerequisites of System.Value_F
105
106   OK_Put_64 : constant Boolean :=
107     Num'Base'Object_Size <= 64
108       and then
109         ((Num'Small_Numerator = 1 and then Num'Small_Denominator <= 2**63)
110           or else
111          (Num'Small_Denominator = 1 and then Num'Small_Numerator <= 2**63)
112           or else
113          (Num'Small_Numerator < Num'Small_Denominator
114            and then Num'Small_Denominator <= 2**59)
115           or else
116          (Num'Small_Denominator < Num'Small_Numerator
117            and then Num'Small_Numerator <= 2**53));
118   --  These conditions are derived from the prerequisites of System.Image_F
119
120   E : constant Natural := 63 - 32 * Boolean'Pos (OK_Put_32);
121   --  T'Size - 1 for the selected Int{32,64}
122
123   F0 : constant Natural := 0;
124   F1 : constant Natural :=
125          F0 + 18 * Boolean'Pos (2.0**E * Num'Small * 10.0**(-F0) >= 1.0E+18);
126   F2 : constant Natural :=
127          F1 +  9 * Boolean'Pos (2.0**E * Num'Small * 10.0**(-F1) >= 1.0E+9);
128   F3 : constant Natural :=
129          F2 +  5 * Boolean'Pos (2.0**E * Num'Small * 10.0**(-F2) >= 1.0E+5);
130   F4 : constant Natural :=
131          F3 +  3 * Boolean'Pos (2.0**E * Num'Small * 10.0**(-F3) >= 1.0E+3);
132   F5 : constant Natural :=
133          F4 +  2 * Boolean'Pos (2.0**E * Num'Small * 10.0**(-F4) >= 1.0E+2);
134   F6 : constant Natural :=
135          F5 +  1 * Boolean'Pos (2.0**E * Num'Small * 10.0**(-F5) >= 1.0E+1);
136   --  Binary search for the number of digits - 1 before the decimal point of
137   --  the product 2.0**E * Num'Small.
138
139   For0 : constant Natural := 2 + F6;
140   --  Fore value for the fixed point type whose mantissa is Int{32,64} and
141   --  whose small is Num'Small.
142
143   ---------
144   -- Get --
145   ---------
146
147   procedure Get
148     (File  : File_Type;
149      Item  : out Num;
150      Width : Field := 0)
151   is
152      pragma Unsuppress (Range_Check);
153
154   begin
155      if OK_Get_32 then
156         Item := Num'Fixed_Value
157                   (Aux32.Get (File, Width,
158                               -Num'Small_Numerator,
159                               -Num'Small_Denominator));
160      elsif OK_Get_64 then
161         Item := Num'Fixed_Value
162                   (Aux64.Get (File, Width,
163                               -Num'Small_Numerator,
164                               -Num'Small_Denominator));
165      else
166         Aux_Long_Float.Get (File, Long_Float (Item), Width);
167      end if;
168
169   exception
170      when Constraint_Error => raise Data_Error;
171   end Get;
172
173   procedure Get
174     (Item  : out Num;
175      Width : Field := 0)
176   is
177   begin
178      Get (Current_In, Item, Width);
179   end Get;
180
181   procedure Get
182     (From : Wide_String;
183      Item : out Num;
184      Last : out Positive)
185   is
186      pragma Unsuppress (Range_Check);
187
188      S : constant String := Wide_String_To_String (From, WCEM_Upper);
189      --  String on which we do the actual conversion. Note that the method
190      --  used for wide character encoding is irrelevant, since if there is
191      --  a character outside the Standard.Character range then the call to
192      --  Aux.Gets will raise Data_Error in any case.
193
194   begin
195      if OK_Get_32 then
196         Item := Num'Fixed_Value
197                   (Aux32.Gets (S, Last,
198                                -Num'Small_Numerator,
199                                -Num'Small_Denominator));
200      elsif OK_Get_64 then
201         Item := Num'Fixed_Value
202                   (Aux64.Gets (S, Last,
203                                -Num'Small_Numerator,
204                                -Num'Small_Denominator));
205      else
206         Aux_Long_Float.Gets (S, Long_Float (Item), Last);
207      end if;
208
209   exception
210      when Constraint_Error => raise Data_Error;
211   end Get;
212
213   ---------
214   -- Put --
215   ---------
216
217   procedure Put
218     (File : File_Type;
219      Item : Num;
220      Fore : Field := Default_Fore;
221      Aft  : Field := Default_Aft;
222      Exp  : Field := Default_Exp)
223   is
224   begin
225      if OK_Put_32 then
226         Aux32.Put (File, Int32'Integer_Value (Item), Fore, Aft, Exp,
227                    -Num'Small_Numerator, -Num'Small_Denominator,
228                    For0, Num'Aft);
229      elsif OK_Put_64 then
230         Aux64.Put (File, Int64'Integer_Value (Item), Fore, Aft, Exp,
231                    -Num'Small_Numerator, -Num'Small_Denominator,
232                    For0, Num'Aft);
233      else
234         Aux_Long_Float.Put (File, Long_Float (Item), Fore, Aft, Exp);
235      end if;
236   end Put;
237
238   procedure Put
239     (Item : Num;
240      Fore : Field := Default_Fore;
241      Aft  : Field := Default_Aft;
242      Exp  : Field := Default_Exp)
243   is
244   begin
245      Put (Current_Out, Item, Fore, Aft, Exp);
246   end Put;
247
248   procedure Put
249     (To   : out Wide_String;
250      Item : Num;
251      Aft  : Field := Default_Aft;
252      Exp  : Field := Default_Exp)
253   is
254      S : String (To'First .. To'Last);
255
256   begin
257      if OK_Put_32 then
258         Aux32.Puts (S, Int32'Integer_Value (Item), Aft, Exp,
259                     -Num'Small_Numerator, -Num'Small_Denominator,
260                     For0, Num'Aft);
261      elsif OK_Put_64 then
262         Aux64.Puts (S, Int64'Integer_Value (Item), Aft, Exp,
263                     -Num'Small_Numerator, -Num'Small_Denominator,
264                     For0, Num'Aft);
265      else
266         Aux_Long_Float.Puts (S, Long_Float (Item), Aft, Exp);
267      end if;
268
269      for J in S'Range loop
270         To (J) := Wide_Character'Val (Character'Pos (S (J)));
271      end loop;
272   end Put;
273
274end Ada.Wide_Text_IO.Fixed_IO;
275