File : s-vallli.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S Y S T E M . V A L _ L L I --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2009, 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 routines for scanning signed Long_Long_Integer
33 -- values for use in Text_IO.Integer_IO, and the Value attribute.
34
35 package System.Val_LLI is
36 pragma Pure;
37
38 function Scan_Long_Long_Integer
39 (Str : String;
40 Ptr : not null access Integer;
41 Max : Integer) return Long_Long_Integer;
42 -- This function scans the string starting at Str (Ptr.all) for a valid
43 -- integer according to the syntax described in (RM 3.5(43)). The substring
44 -- scanned extends no further than Str (Max). There are three cases for the
45 -- return:
46 --
47 -- If a valid integer is found after scanning past any initial spaces, then
48 -- Ptr.all is updated past the last character of the integer (but trailing
49 -- spaces are not scanned out).
50 --
51 -- If no valid integer is found, then Ptr.all points either to an initial
52 -- non-digit character, or to Max + 1 if the field is all spaces and the
53 -- exception Constraint_Error is raised.
54 --
55 -- If a syntactically valid integer is scanned, but the value is out of
56 -- range, or, in the based case, the base value is out of range or there
57 -- is an out of range digit, then Ptr.all points past the integer, and
58 -- Constraint_Error is raised.
59 --
60 -- Note: these rules correspond to the requirements for leaving the pointer
61 -- positioned in Text_Io.Get
62 --
63 -- Note: if Str is null, i.e. if Max is less than Ptr, then this is a
64 -- special case of an all-blank string, and Ptr is unchanged, and hence
65 -- is greater than Max as required in this case.
66
67 function Value_Long_Long_Integer (Str : String) return Long_Long_Integer;
68 -- Used in computing X'Value (Str) where X is a signed integer type whose
69 -- base range exceeds the base range of Integer. Str is the string argument
70 -- of the attribute. Constraint_Error is raised if the string is malformed,
71 -- or if the value is out of range.
72
73 end System.Val_LLI;