File : switch.ads
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- S W I T C H --
6 -- --
7 -- S p e c --
8 -- --
9 -- Copyright (C) 1992-2012, 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. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING3. If not, go to --
19 -- http://www.gnu.org/licenses for a complete copy of the license. --
20 -- --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
23 -- --
24 ------------------------------------------------------------------------------
25
26 -- This package together with a child package appropriate to the client tool
27 -- scans switches. Note that the body of the appropriate Usage package must be
28 -- coordinated with the switches that are recognized by this package. These
29 -- Usage packages also act as the official documentation for the switches
30 -- that are recognized. In addition, package Debug documents the otherwise
31 -- undocumented debug switches that are also recognized.
32
33 with Gnatvsn;
34 with Types; use Types;
35
36 ------------
37 -- Switch --
38 ------------
39
40 package Switch is
41
42 -- Common switches for GNU tools
43
44 Version_Switch : constant String := "--version";
45 Help_Switch : constant String := "--help";
46
47 -----------------
48 -- Subprograms --
49 -----------------
50
51 generic
52 with procedure Usage;
53 -- Print tool-specific part of --help message
54 procedure Check_Version_And_Help_G
55 (Tool_Name : String;
56 Initial_Year : String;
57 Version_String : String := Gnatvsn.Gnat_Version_String);
58 -- Check if switches --version or --help is used. If one of this switch is
59 -- used, issue the proper messages and end the process.
60
61 procedure Display_Version
62 (Tool_Name : String;
63 Initial_Year : String;
64 Version_String : String := Gnatvsn.Gnat_Version_String);
65 -- Display version of a tool when switch --version is used
66
67 procedure Display_Usage_Version_And_Help;
68 -- Output the two lines of usage for switches --version and --help
69
70 function Is_Switch (Switch_Chars : String) return Boolean;
71 -- Returns True iff Switch_Chars is at least two characters long, and the
72 -- first character is an hyphen ('-').
73
74 function Is_Front_End_Switch (Switch_Chars : String) return Boolean;
75 -- Returns True iff Switch_Chars represents a front-end switch, i.e. it
76 -- starts with -I, -gnat or -?RTS.
77
78 function Is_Internal_GCC_Switch (Switch_Chars : String) return Boolean;
79 -- Returns True iff Switch_Chars represents an internal GCC switch to be
80 -- followed by a single argument, such as -dumpbase, --param or -auxbase.
81 -- Even though passed by the "gcc" driver, these need not be stored in ALI
82 -- files and may safely be ignored by non GCC back-ends.
83
84 function Switch_Last (Switch_Chars : String) return Natural;
85 -- Index in Switch_Chars of the last relevant character for later string
86 -- comparison purposes. This is typically 'Last, minus one if there is a
87 -- terminating ASCII.NUL.
88
89 private
90 -- This section contains some common routines used by the tool dependent
91 -- child packages (there is one such child package for each tool that uses
92 -- Switches to scan switches - Compiler/gnatbind/gnatmake/.
93
94 Switch_Max_Value : constant := 999_999;
95 -- Maximum value permitted in switches that take a value
96
97 function Nat_Present
98 (Switch_Chars : String;
99 Max : Integer;
100 Ptr : Integer) return Boolean;
101 -- Returns True if an integer is at the current scan location or an equal
102 -- sign. This is used as a guard for calling Scan_Nat. Switch_Chars is the
103 -- string containing the switch, and Ptr points just past the switch
104 -- character. Max is the maximum allowed value of Ptr.
105
106 procedure Scan_Nat
107 (Switch_Chars : String;
108 Max : Integer;
109 Ptr : in out Integer;
110 Result : out Nat;
111 Switch : Character);
112 -- Scan natural integer parameter for switch. On entry, Ptr points just
113 -- past the switch character, on exit it points past the last digit of the
114 -- integer value. Max is the maximum allowed value of Ptr, so the scan is
115 -- restricted to Switch_Chars (Ptr .. Max). It is possible for Ptr to be
116 -- one greater than Max on return if the entire string is digits. Scan_Nat
117 -- will skip an optional equal sign if it is present. Nat_Present must be
118 -- True, or an error will be signalled.
119
120 procedure Scan_Pos
121 (Switch_Chars : String;
122 Max : Integer;
123 Ptr : in out Integer;
124 Result : out Pos;
125 Switch : Character);
126 -- Scan positive integer parameter for switch. Identical to Scan_Nat with
127 -- same parameters except that zero is considered out of range.
128
129 procedure Bad_Switch (Switch : Character);
130 procedure Bad_Switch (Switch : String);
131 pragma No_Return (Bad_Switch);
132 -- Fail with an appropriate message when a switch is not recognized
133
134 end Switch;