1------------------------------------------------------------------------------
2--                                                                          --
3--                         GNAT COMPILER COMPONENTS                         --
4--                                                                          --
5--                               C A S I N G                                --
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.  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
26with Csets;    use Csets;
27with Opt;      use Opt;
28with Widechar; use Widechar;
29
30package body Casing is
31
32   ----------------------
33   -- Determine_Casing --
34   ----------------------
35
36   function Determine_Casing (Ident : Text_Buffer) return Casing_Type is
37
38      All_Lower : Boolean := True;
39      --  Set False if upper case letter found
40
41      All_Upper : Boolean := True;
42      --  Set False if lower case letter found
43
44      Mixed : Boolean := True;
45      --  Set False if exception to mixed case rule found (lower case letter
46      --  at start or after underline, or upper case letter elsewhere).
47
48      Decisive : Boolean := False;
49      --  Set True if at least one instance of letter not after underline
50
51      After_Und : Boolean := True;
52      --  True at start of string, and after an underline character
53
54   begin
55      --  A special exception, consider SPARK_Mode to be mixed case
56
57      if Ident = "SPARK_Mode" then
58         return Mixed_Case;
59      end if;
60
61      --  Proceed with normal determination
62
63      for S in Ident'Range loop
64         if Ident (S) = '_' or else Ident (S) = '.' then
65            After_Und := True;
66
67         elsif Is_Lower_Case_Letter (Ident (S)) then
68            All_Upper := False;
69
70            if not After_Und then
71               Decisive := True;
72            else
73               After_Und := False;
74               Mixed := False;
75            end if;
76
77         elsif Is_Upper_Case_Letter (Ident (S)) then
78            All_Lower := False;
79
80            if not After_Und then
81               Decisive := True;
82               Mixed := False;
83            else
84               After_Und := False;
85            end if;
86         end if;
87      end loop;
88
89      --  Now we can figure out the result from the flags we set in that loop
90
91      if All_Lower then
92         return All_Lower_Case;
93
94      elsif not Decisive then
95         return Unknown;
96
97      elsif All_Upper then
98         return All_Upper_Case;
99
100      elsif Mixed then
101         return Mixed_Case;
102
103      else
104         return Unknown;
105      end if;
106   end Determine_Casing;
107
108   ------------------------
109   -- Set_All_Upper_Case --
110   ------------------------
111
112   procedure Set_All_Upper_Case is
113   begin
114      Set_Casing (All_Upper_Case);
115   end Set_All_Upper_Case;
116
117   ----------------
118   -- Set_Casing --
119   ----------------
120
121   procedure Set_Casing
122     (Buf : in out Bounded_String;
123      C   : Casing_Type;
124      D   : Casing_Type := Mixed_Case)
125   is
126      Ptr : Natural;
127
128      Actual_Casing : Casing_Type;
129      --  Set from C or D as appropriate
130
131      After_Und : Boolean := True;
132      --  True at start of string, and after an underline character or after
133      --  any other special character that is not a normal identifier char).
134
135   begin
136      if C /= Unknown then
137         Actual_Casing := C;
138      else
139         Actual_Casing := D;
140      end if;
141
142      Ptr := 1;
143
144      while Ptr <= Buf.Length loop
145
146         --  Wide character. Note that we do nothing with casing in this case.
147         --  In Ada 2005 mode, required folding of lower case letters happened
148         --  as the identifier was scanned, and we do not attempt any further
149         --  messing with case (note that in any case we do not know how to
150         --  fold upper case to lower case in wide character mode). We also
151         --  do not bother with recognizing punctuation as equivalent to an
152         --  underscore. There is nothing functional at this stage in doing
153         --  the requested casing operation, beyond folding to upper case
154         --  when it is mandatory, which does not involve underscores.
155
156         if Buf.Chars (Ptr) = ASCII.ESC
157           or else Buf.Chars (Ptr) = '['
158           or else (Upper_Half_Encoding
159                     and then Buf.Chars (Ptr) in Upper_Half_Character)
160         then
161            Skip_Wide (Buf.Chars, Ptr);
162            After_Und := False;
163
164         --  Underscore, or non-identifer character (error case)
165
166         elsif Buf.Chars (Ptr) = '_'
167           or else not Identifier_Char (Buf.Chars (Ptr))
168         then
169            After_Und := True;
170            Ptr := Ptr + 1;
171
172         --  Lower case letter
173
174         elsif Is_Lower_Case_Letter (Buf.Chars (Ptr)) then
175            if Actual_Casing = All_Upper_Case
176              or else (After_Und and then Actual_Casing = Mixed_Case)
177            then
178               Buf.Chars (Ptr) := Fold_Upper (Buf.Chars (Ptr));
179            end if;
180
181            After_Und := False;
182            Ptr := Ptr + 1;
183
184         --  Upper case letter
185
186         elsif Is_Upper_Case_Letter (Buf.Chars (Ptr)) then
187            if Actual_Casing = All_Lower_Case
188              or else (not After_Und and then Actual_Casing = Mixed_Case)
189            then
190               Buf.Chars (Ptr) := Fold_Lower (Buf.Chars (Ptr));
191            end if;
192
193            After_Und := False;
194            Ptr := Ptr + 1;
195
196         --  Other identifier character (must be digit)
197
198         else
199            After_Und := False;
200            Ptr := Ptr + 1;
201         end if;
202      end loop;
203   end Set_Casing;
204
205   procedure Set_Casing (C : Casing_Type; D : Casing_Type := Mixed_Case) is
206   begin
207      Set_Casing (Global_Name_Buffer, C, D);
208   end Set_Casing;
209
210end Casing;
211