1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
9 -- Copyright (C) 1992-2008, Free Software Foundation, Inc. --
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. --
21 -- GNAT was originally developed by the GNAT team at New York University. --
22 -- Extensive contributions were provided by Ada Core Technologies Inc. --
24 ------------------------------------------------------------------------------
26 with Atree; use Atree;
27 with Csets; use Csets;
28 with Hostparm; use Hostparm;
29 with Namet; use Namet;
31 with Output; use Output;
32 with Restrict; use Restrict;
33 with Rident; use Rident;
34 with Scans; use Scans;
35 with Sinfo; use Sinfo;
36 with Sinput; use Sinput;
37 with Uintp; use Uintp;
39 with GNAT.Byte_Order_Mark; use GNAT.Byte_Order_Mark;
41 with System.WCh_Con; use System.WCh_Con;
47 Used_As_Identifier : array (Token_Type) of Boolean;
48 -- Flags set True if a given keyword is used as an identifier (used to
49 -- make sure that we only post an error message for incorrect use of a
50 -- keyword as an identifier once for a given keyword).
52 procedure Check_End_Of_Line;
53 -- Called when end of line encountered. Checks that line is not too long,
54 -- and that other style checks for the end of line are met.
56 function Determine_License return License_Type;
57 -- Scan header of file and check that it has an appropriate GNAT-style
58 -- header with a proper license statement. Returns GPL, Unrestricted,
59 -- or Modified_GPL depending on header. If none of these, returns Unknown.
61 procedure Error_Long_Line;
62 -- Signal error of excessively long line
64 -----------------------
65 -- Check_End_Of_Line --
66 -----------------------
68 procedure Check_End_Of_Line is
69 Len : constant Int := Int (Scan_Ptr) - Int (Current_Line_Start);
72 Style.Check_Line_Terminator (Len);
73 elsif Len > Max_Line_Length then
76 end Check_End_Of_Line;
78 -----------------------
79 -- Determine_License --
80 -----------------------
82 function Determine_License return License_Type is
83 GPL_Found : Boolean := False;
84 Result : License_Type;
86 function Contains (S : String) return Boolean;
87 -- See if current comment contains successive non-blank characters
88 -- matching the contents of S. If so leave Scan_Ptr unchanged and
89 -- return True, otherwise leave Scan_Ptr unchanged and return False.
92 -- Skip to line terminator character
98 function Contains (S : String) return Boolean is
104 -- Loop to check characters. This loop is terminated by end of
105 -- line, and also we need to check for the EOF case, to take
106 -- care of files containing only comments.
109 while Source (SP) /= CR and then
110 Source (SP) /= LF and then
113 if Source (SP) = S (S'First) then
125 while Source (SS) = ' ' loop
129 exit when Source (SS) /= S (CP);
143 procedure Skip_EOL is
145 while Source (Scan_Ptr) /= CR
146 and then Source (Scan_Ptr) /= LF
147 and then Source (Scan_Ptr) /= EOF
149 Scan_Ptr := Scan_Ptr + 1;
153 -- Start of processing for Determine_License
157 if Source (Scan_Ptr) /= '-'
158 or else Source (Scan_Ptr + 1) /= '-'
168 elsif Contains ("Asaspecialexception") then
170 Result := Modified_GPL;
174 elsif Contains ("GNUGeneralPublicLicense") then
179 ("ThisspecificationisadaptedfromtheAdaSemanticInterface")
182 ("ThisspecificationisderivedfromtheAdaReferenceManual")
184 Result := Unrestricted;
192 if Source (Scan_Ptr) /= EOF then
194 -- We have to take into account a degenerate case when the source
195 -- file contains only comments and no Ada code.
201 Skip_Line_Terminators (Scan_Ptr, Physical);
203 -- If we are at start of physical line, update scan pointers
204 -- to reflect the start of the new line.
207 Current_Line_Start := Scan_Ptr;
208 Start_Column := Scanner.Set_Start_Column;
209 First_Non_Blank_Location := Scan_Ptr;
216 end Determine_License;
218 ----------------------------
219 -- Determine_Token_Casing --
220 ----------------------------
222 function Determine_Token_Casing return Casing_Type is
224 return Scanner.Determine_Token_Casing;
225 end Determine_Token_Casing;
227 ---------------------
228 -- Error_Long_Line --
229 ---------------------
231 procedure Error_Long_Line is
234 ("this line is too long",
235 Current_Line_Start + Source_Ptr (Max_Line_Length));
238 ------------------------
239 -- Initialize_Scanner --
240 ------------------------
242 procedure Initialize_Scanner
243 (Unit : Unit_Number_Type;
244 Index : Source_File_Index)
246 GNAT_Hedr : constant Text_Buffer (1 .. 78) := (others => '-');
249 Scanner.Initialize_Scanner (Index);
251 if Index /= Internal_Source_File then
252 Set_Unit (Index, Unit);
255 Current_Source_Unit := Unit;
257 -- Set default for Comes_From_Source (except if we are going to process
258 -- an artificial string internally created within the compiler and
259 -- placed into internal source duffer). All nodes built now until we
260 -- reenter the analyzer will have Comes_From_Source set to True
262 if Index /= Internal_Source_File then
263 Set_Comes_From_Source_Default (True);
266 -- Check license if GNAT type header possibly present
268 if Source_Last (Index) - Scan_Ptr > 80
269 and then Source (Scan_Ptr .. Scan_Ptr + 77) = GNAT_Hedr
271 Set_License (Current_Source_File, Determine_License);
279 Tst : String (1 .. 5);
283 Tst (J) := Source (Scan_Ptr + Source_Ptr (J) - 1);
286 Read_BOM (Tst, Len, BOM, False);
290 Scan_Ptr := Scan_Ptr + Source_Ptr (Len);
291 Wide_Character_Encoding_Method := WCEM_UTF8;
292 Upper_Half_Encoding := True;
294 when UTF16_LE | UTF16_BE =>
296 Write_Line ("UTF-16 encoding format not recognized");
298 raise Unrecoverable_Error;
300 when UTF32_LE | UTF32_BE =>
302 Write_Line ("UTF-32 encoding format not recognized");
304 raise Unrecoverable_Error;
314 -- Because of the License stuff above, Scng.Initialize_Scanner cannot
315 -- call Scan. Scan initial token (note this initializes Prev_Token,
318 -- There are two reasons not to do the Scan step in case if we
319 -- initialize the scanner for the internal source buffer:
321 -- - The artificial string may not be created by the compiler in this
322 -- buffer when we call Initialize_Scanner
324 -- - For these artificial strings a special way of scanning is used, so
325 -- the standard step of the scanner may just break the algorithm of
326 -- processing these strings.
328 if Index /= Internal_Source_File then
332 -- Clear flags for reserved words used as identifiers
334 for J in Token_Type loop
335 Used_As_Identifier (J) := False;
337 end Initialize_Scanner;
339 -----------------------
340 -- Obsolescent_Check --
341 -----------------------
343 procedure Obsolescent_Check (S : Source_Ptr) is
345 -- This is a pain in the neck case, since we normally need a node to
346 -- call Check_Restrictions, and all we have is a source pointer. The
347 -- easiest thing is to construct a dummy node. A bit kludgy, but this
348 -- is a marginal case. It's not worth trying to do things more cleanly.
350 Check_Restriction (No_Obsolescent_Features, New_Node (N_Empty, S));
351 end Obsolescent_Check;
357 procedure Post_Scan is
360 when Tok_Char_Literal =>
361 Token_Node := New_Node (N_Character_Literal, Token_Ptr);
362 Set_Char_Literal_Value (Token_Node, UI_From_CC (Character_Code));
363 Set_Chars (Token_Node, Token_Name);
365 when Tok_Identifier =>
366 Token_Node := New_Node (N_Identifier, Token_Ptr);
367 Set_Chars (Token_Node, Token_Name);
369 when Tok_Real_Literal =>
370 Token_Node := New_Node (N_Real_Literal, Token_Ptr);
371 Set_Realval (Token_Node, Real_Literal_Value);
373 when Tok_Integer_Literal =>
374 Token_Node := New_Node (N_Integer_Literal, Token_Ptr);
375 Set_Intval (Token_Node, Int_Literal_Value);
377 when Tok_String_Literal =>
378 Token_Node := New_Node (N_String_Literal, Token_Ptr);
379 Set_Has_Wide_Character (Token_Node, Wide_Character_Found);
380 Set_Strval (Token_Node, String_Literal_Id);
382 when Tok_Operator_Symbol =>
383 Token_Node := New_Node (N_Operator_Symbol, Token_Ptr);
384 Set_Chars (Token_Node, Token_Name);
385 Set_Strval (Token_Node, String_Literal_Id);
392 ------------------------------
393 -- Scan_Reserved_Identifier --
394 ------------------------------
396 procedure Scan_Reserved_Identifier (Force_Msg : Boolean) is
397 Token_Chars : constant String := Token_Type'Image (Token);
400 -- We have in Token_Chars the image of the Token name, i.e. Tok_xxx.
401 -- This code extracts the xxx and makes an identifier out of it.
405 for J in 5 .. Token_Chars'Length loop
406 Name_Len := Name_Len + 1;
407 Name_Buffer (Name_Len) := Fold_Lower (Token_Chars (J));
410 Token_Name := Name_Find;
412 if not Used_As_Identifier (Token) or else Force_Msg then
413 Error_Msg_Name_1 := Token_Name;
414 Error_Msg_SC ("reserved word* cannot be used as identifier!");
415 Used_As_Identifier (Token) := True;
418 Token := Tok_Identifier;
419 Token_Node := New_Node (N_Identifier, Token_Ptr);
420 Set_Chars (Token_Node, Token_Name);
421 end Scan_Reserved_Identifier;