File : s-vallli.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S Y S T E M . V A L _ L L I --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2014, 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 System.Unsigned_Types; use System.Unsigned_Types;
33 with System.Val_LLU; use System.Val_LLU;
34 with System.Val_Util; use System.Val_Util;
35
36 package body System.Val_LLI is
37
38 ----------------------------
39 -- Scan_Long_Long_Integer --
40 ----------------------------
41
42 function Scan_Long_Long_Integer
43 (Str : String;
44 Ptr : not null access Integer;
45 Max : Integer) return Long_Long_Integer
46 is
47 Uval : Long_Long_Unsigned;
48 -- Unsigned result
49
50 Minus : Boolean := False;
51 -- Set to True if minus sign is present, otherwise to False
52
53 Start : Positive;
54 -- Saves location of first non-blank
55
56 begin
57 Scan_Sign (Str, Ptr, Max, Minus, Start);
58
59 if Str (Ptr.all) not in '0' .. '9' then
60 Ptr.all := Start;
61 Bad_Value (Str);
62 end if;
63
64 Uval := Scan_Raw_Long_Long_Unsigned (Str, Ptr, Max);
65
66 -- Deal with overflow cases, and also with maximum negative number
67
68 if Uval > Long_Long_Unsigned (Long_Long_Integer'Last) then
69 if Minus
70 and then Uval = Long_Long_Unsigned (-(Long_Long_Integer'First))
71 then
72 return Long_Long_Integer'First;
73 else
74 Bad_Value (Str);
75 end if;
76
77 -- Negative values
78
79 elsif Minus then
80 return -(Long_Long_Integer (Uval));
81
82 -- Positive values
83
84 else
85 return Long_Long_Integer (Uval);
86 end if;
87 end Scan_Long_Long_Integer;
88
89 -----------------------------
90 -- Value_Long_Long_Integer --
91 -----------------------------
92
93 function Value_Long_Long_Integer (Str : String) return Long_Long_Integer is
94 begin
95 -- We have to special case Str'Last = Positive'Last because the normal
96 -- circuit ends up setting P to Str'Last + 1 which is out of bounds. We
97 -- deal with this by converting to a subtype which fixes the bounds.
98
99 if Str'Last = Positive'Last then
100 declare
101 subtype NT is String (1 .. Str'Length);
102 begin
103 return Value_Long_Long_Integer (NT (Str));
104 end;
105
106 -- Normal case where Str'Last < Positive'Last
107
108 else
109 declare
110 V : Long_Long_Integer;
111 P : aliased Integer := Str'First;
112 begin
113 V := Scan_Long_Long_Integer (Str, P'Access, Str'Last);
114 Scan_Trailing_Blanks (Str, P);
115 return V;
116 end;
117 end if;
118 end Value_Long_Long_Integer;
119
120 end System.Val_LLI;