1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT RUN-TIME COMPONENTS                         --
4--                                                                          --
5--             A D A . D I R E C T O R I E S . V A L I D I T Y              --
6--                                                                          --
7--                                 B o d y                                  --
8--                              (VMS Version)                               --
9--                                                                          --
10--          Copyright (C) 2004-2012, Free Software Foundation, Inc.         --
11--                                                                          --
12-- GNAT is free software;  you can  redistribute it  and/or modify it under --
13-- terms of the  GNU General Public License as published  by the Free Soft- --
14-- ware  Foundation;  either version 3,  or (at your option) any later ver- --
15-- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
16-- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
17-- or FITNESS FOR A PARTICULAR PURPOSE.                                     --
18--                                                                          --
19-- As a special exception under Section 7 of GPL version 3, you are granted --
20-- additional permissions described in the GCC Runtime Library Exception,   --
21-- version 3.1, as published by the Free Software Foundation.               --
22--                                                                          --
23-- You should have received a copy of the GNU General Public License and    --
24-- a copy of the GCC Runtime Library Exception along with this program;     --
25-- see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see    --
26-- <http://www.gnu.org/licenses/>.                                          --
27--                                                                          --
28-- GNAT was originally developed  by the GNAT team at  New York University. --
29-- Extensive contributions were provided by Ada Core Technologies Inc.      --
30--                                                                          --
31------------------------------------------------------------------------------
32
33--  This is the OpenVMS version of this package
34
35package body Ada.Directories.Validity is
36
37   Max_Number_Of_Characters : constant := 39;
38   Max_Path_Length          : constant := 1_024;
39
40   Invalid_Character : constant array (Character) of Boolean :=
41     ('a' .. 'z' => False,
42      'A' .. 'Z' => False,
43      '0' .. '9' => False,
44      '_' | '$' | '-' | '.' => False,
45      others => True);
46
47   ---------------------------------
48   -- Is_Path_Name_Case_Sensitive --
49   ---------------------------------
50
51   function Is_Path_Name_Case_Sensitive return Boolean is
52   begin
53      return False;
54   end Is_Path_Name_Case_Sensitive;
55
56   ------------------------
57   -- Is_Valid_Path_Name --
58   ------------------------
59
60   function Is_Valid_Path_Name (Name : String) return Boolean is
61      First     : Positive := Name'First;
62      Last      : Positive;
63      Dot_Found : Boolean := False;
64
65   begin
66      --  A valid path (directory) name cannot be empty, and cannot contain
67      --  more than 1024 characters. Directories can be ".", ".." or be simple
68      --  name without extensions.
69
70      if Name'Length = 0 or else Name'Length > Max_Path_Length then
71         return False;
72
73      else
74         loop
75            --  Look for the start of the next directory or file name
76
77            while First <= Name'Last and then Name (First) = '/' loop
78               First := First + 1;
79            end loop;
80
81            --  If all directories/file names are OK, return True
82
83            exit when First > Name'Last;
84
85            Last := First;
86            Dot_Found := False;
87
88            --  Look for the end of the directory/file name
89
90            while Last < Name'Last loop
91               exit when Name (Last + 1) = '/';
92               Last := Last + 1;
93
94               if Name (Last) = '.' then
95                  Dot_Found := True;
96               end if;
97            end loop;
98
99            --  If name include a dot, it can only be ".", ".." or the last
100            --  file name.
101
102            if Dot_Found then
103               if Name (First .. Last) /= "." and then
104                  Name (First .. Last) /= ".."
105               then
106                  return Last = Name'Last
107                    and then Is_Valid_Simple_Name (Name (First .. Last));
108
109               end if;
110
111            --  Check if the directory/file name is valid
112
113            elsif not Is_Valid_Simple_Name (Name (First .. Last)) then
114                  return False;
115            end if;
116
117            --  Move to the next name
118
119            First := Last + 1;
120         end loop;
121      end if;
122
123      --  If Name follows the rules, then it is valid
124
125      return True;
126   end Is_Valid_Path_Name;
127
128   --------------------------
129   -- Is_Valid_Simple_Name --
130   --------------------------
131
132   function Is_Valid_Simple_Name (Name : String) return Boolean is
133      In_Extension         : Boolean := False;
134      Number_Of_Characters : Natural := 0;
135
136   begin
137      --  A file name cannot be empty, and cannot have more than 39 characters
138      --  before or after a single '.'.
139
140      if Name'Length = 0 then
141         return False;
142
143      else
144         --  Check each character for validity
145
146         for J in Name'Range loop
147            if Invalid_Character (Name (J)) then
148               return False;
149
150            elsif Name (J) = '.' then
151
152               --  Name cannot contain several dots
153
154               if In_Extension then
155                  return False;
156
157               else
158                  --  Reset the number of characters to count the characters
159                  --  of the extension.
160
161                  In_Extension := True;
162                  Number_Of_Characters := 0;
163               end if;
164
165            else
166               --  Check that the number of character is not too large
167
168               Number_Of_Characters := Number_Of_Characters + 1;
169
170               if Number_Of_Characters > Max_Number_Of_Characters then
171                  return False;
172               end if;
173            end if;
174         end loop;
175      end if;
176
177      --  If the rules are followed, then it is valid
178
179      return True;
180   end Is_Valid_Simple_Name;
181
182   -------------
183   -- OpenVMS --
184   -------------
185
186   function OpenVMS return Boolean is
187   begin
188      return True;
189   end OpenVMS;
190
191   -------------
192   -- Windows --
193   -------------
194
195   function Windows return Boolean is
196   begin
197      return False;
198   end Windows;
199
200end Ada.Directories.Validity;
201