File : ali-util.adb
1 ------------------------------------------------------------------------------
2 -- --
3 -- GNAT COMPILER COMPONENTS --
4 -- --
5 -- A L I . U T I L --
6 -- --
7 -- B o d y --
8 -- --
9 -- Copyright (C) 1992-2014, 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 with Debug; use Debug;
27 with Binderr; use Binderr;
28 with Opt; use Opt;
29 with Output; use Output;
30 with Osint; use Osint;
31 with Scans; use Scans;
32 with Scng;
33 with Sinput.C;
34 with Snames; use Snames;
35 with Stringt;
36 with Styleg;
37
38 with System.OS_Lib; use System.OS_Lib;
39
40 package body ALI.Util is
41
42 -- Empty procedures needed to instantiate Scng. Error procedures are
43 -- empty, because we don't want to report any errors when computing
44 -- a source checksum.
45
46 procedure Post_Scan;
47
48 procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr);
49
50 procedure Error_Msg_S (Msg : String);
51
52 procedure Error_Msg_SC (Msg : String);
53
54 procedure Error_Msg_SP (Msg : String);
55
56 -- Instantiation of Styleg, needed to instantiate Scng
57
58 package Style is new Styleg
59 (Error_Msg, Error_Msg_S, Error_Msg_SC, Error_Msg_SP);
60
61 -- A Scanner is needed to get checksum of a source (procedure
62 -- Get_File_Checksum).
63
64 package Scanner is new Scng
65 (Post_Scan, Error_Msg, Error_Msg_S, Error_Msg_SC, Error_Msg_SP, Style);
66
67 type Header_Num is range 0 .. 1_000;
68
69 function Hash (F : File_Name_Type) return Header_Num;
70 -- Function used to compute hash of ALI file name
71
72 package Interfaces is new Simple_HTable (
73 Header_Num => Header_Num,
74 Element => Boolean,
75 No_Element => False,
76 Key => File_Name_Type,
77 Hash => Hash,
78 Equal => "=");
79
80 ---------------------
81 -- Checksums_Match --
82 ---------------------
83
84 function Checksums_Match (Checksum1, Checksum2 : Word) return Boolean is
85 begin
86 return Checksum1 = Checksum2 and then Checksum1 /= Checksum_Error;
87 end Checksums_Match;
88
89 ---------------
90 -- Error_Msg --
91 ---------------
92
93 procedure Error_Msg (Msg : String; Flag_Location : Source_Ptr) is
94 pragma Warnings (Off, Msg);
95 pragma Warnings (Off, Flag_Location);
96 begin
97 null;
98 end Error_Msg;
99
100 -----------------
101 -- Error_Msg_S --
102 -----------------
103
104 procedure Error_Msg_S (Msg : String) is
105 pragma Warnings (Off, Msg);
106 begin
107 null;
108 end Error_Msg_S;
109
110 ------------------
111 -- Error_Msg_SC --
112 ------------------
113
114 procedure Error_Msg_SC (Msg : String) is
115 pragma Warnings (Off, Msg);
116 begin
117 null;
118 end Error_Msg_SC;
119
120 ------------------
121 -- Error_Msg_SP --
122 ------------------
123
124 procedure Error_Msg_SP (Msg : String) is
125 pragma Warnings (Off, Msg);
126 begin
127 null;
128 end Error_Msg_SP;
129
130 -----------------------
131 -- Get_File_Checksum --
132 -----------------------
133
134 function Get_File_Checksum (Fname : File_Name_Type) return Word is
135 Full_Name : File_Name_Type;
136 Source_Index : Source_File_Index;
137
138 begin
139 Full_Name := Find_File (Fname, Osint.Source);
140
141 -- If we cannot find the file, then return an impossible checksum,
142 -- impossible because checksums have the high order bit zero, so
143 -- that checksums do not match.
144
145 if Full_Name = No_File then
146 return Checksum_Error;
147 end if;
148
149 Source_Index := Sinput.C.Load_File (Get_Name_String (Full_Name));
150
151 if Source_Index = No_Source_File then
152 return Checksum_Error;
153 end if;
154
155 Scanner.Initialize_Scanner (Source_Index);
156
157 -- Make sure that the project language reserved words are not
158 -- recognized as reserved words, but as identifiers. The byte info for
159 -- those names have been set if we are in gnatmake.
160
161 Set_Name_Table_Byte (Name_Project, 0);
162 Set_Name_Table_Byte (Name_Extends, 0);
163 Set_Name_Table_Byte (Name_External, 0);
164 Set_Name_Table_Byte (Name_External_As_List, 0);
165
166 -- Scan the complete file to compute its checksum
167
168 loop
169 Scanner.Scan;
170 exit when Token = Tok_EOF;
171 end loop;
172
173 return Scans.Checksum;
174 end Get_File_Checksum;
175
176 ----------
177 -- Hash --
178 ----------
179
180 function Hash (F : File_Name_Type) return Header_Num is
181 begin
182 return Header_Num (Int (F) rem Header_Num'Range_Length);
183 end Hash;
184
185 ---------------------------
186 -- Initialize_ALI_Source --
187 ---------------------------
188
189 procedure Initialize_ALI_Source is
190 begin
191 -- When (re)initializing ALI data structures the ALI user expects to
192 -- get a fresh set of data structures. Thus we first need to erase the
193 -- marks put in the name table by the previous set of ALI routine calls.
194 -- This loop is empty and harmless the first time in.
195
196 for J in Source.First .. Source.Last loop
197 Set_Name_Table_Int (Source.Table (J).Sfile, 0);
198 Source.Table (J).Source_Found := False;
199 end loop;
200
201 Source.Init;
202 Interfaces.Reset;
203 end Initialize_ALI_Source;
204
205 ---------------
206 -- Post_Scan --
207 ---------------
208
209 procedure Post_Scan is
210 begin
211 null;
212 end Post_Scan;
213
214 ----------------------
215 -- Read_Withed_ALIs --
216 ----------------------
217
218 procedure Read_Withed_ALIs
219 (Id : ALI_Id;
220 Ignore_Errors : Boolean := False)
221 is
222 Afile : File_Name_Type;
223 Text : Text_Buffer_Ptr;
224 Idread : ALI_Id;
225
226 begin
227 -- Process all dependent units
228
229 for U in ALIs.Table (Id).First_Unit .. ALIs.Table (Id).Last_Unit loop
230 for
231 W in Units.Table (U).First_With .. Units.Table (U).Last_With
232 loop
233 Afile := Withs.Table (W).Afile;
234
235 -- Only process if not a generic (Afile /= No_File) and if
236 -- file has not been processed already.
237
238 if Afile /= No_File
239 and then Get_Name_Table_Int (Afile) = 0
240 then
241 Text := Read_Library_Info (Afile);
242
243 -- Unless Ignore_Errors is true, return with an error if source
244 -- cannot be found. We used to skip this check when we did not
245 -- compile library generics separately, but we now always do,
246 -- so there is no special case here anymore.
247
248 if Text = null then
249
250 if not Ignore_Errors then
251 Error_Msg_File_1 := Afile;
252 Error_Msg_File_2 := Withs.Table (W).Sfile;
253 Error_Msg ("{ not found, { must be compiled");
254 Set_Name_Table_Int (Afile, Int (No_Unit_Id));
255 return;
256 end if;
257
258 else
259 -- Enter in ALIs table
260
261 Idread :=
262 Scan_ALI
263 (F => Afile,
264 T => Text,
265 Ignore_ED => False,
266 Err => False);
267
268 Free (Text);
269
270 if ALIs.Table (Idread).Compile_Errors
271 and then not Ignore_Errors
272 then
273 Error_Msg_File_1 := Withs.Table (W).Sfile;
274 Error_Msg ("{ had errors, must be fixed, and recompiled");
275 Set_Name_Table_Int (Afile, Int (No_Unit_Id));
276
277 -- In GNATprove mode, object files are never generated, so
278 -- No_Object=True is not considered an error.
279
280 elsif ALIs.Table (Idread).No_Object
281 and then not GNATprove_Mode
282 and then not Ignore_Errors
283 then
284 Error_Msg_File_1 := Withs.Table (W).Sfile;
285 Error_Msg ("{ must be recompiled");
286 Set_Name_Table_Int (Afile, Int (No_Unit_Id));
287 end if;
288
289 -- If the Unit is an Interface to a Stand-Alone Library,
290 -- set the Interface flag in the Withs table, so that its
291 -- dependant are not considered for elaboration order.
292
293 if ALIs.Table (Idread).SAL_Interface then
294 Withs.Table (W).SAL_Interface := True;
295 Interface_Library_Unit := True;
296
297 -- Set the entry in the Interfaces hash table, so that
298 -- other units that import this unit will set the flag
299 -- in their entry in the Withs table.
300
301 Interfaces.Set (Afile, True);
302
303 else
304 -- Otherwise, recurse to get new dependents
305
306 Read_Withed_ALIs (Idread);
307 end if;
308 end if;
309
310 -- If the ALI file has already been processed and is an interface,
311 -- set the flag in the entry of the Withs table.
312
313 elsif Interface_Library_Unit and then Interfaces.Get (Afile) then
314 Withs.Table (W).SAL_Interface := True;
315 end if;
316 end loop;
317 end loop;
318 end Read_Withed_ALIs;
319
320 ----------------------
321 -- Set_Source_Table --
322 ----------------------
323
324 procedure Set_Source_Table (A : ALI_Id) is
325 F : File_Name_Type;
326 S : Source_Id;
327 Stamp : Time_Stamp_Type;
328
329 begin
330 Sdep_Loop : for D in
331 ALIs.Table (A).First_Sdep .. ALIs.Table (A).Last_Sdep
332 loop
333 F := Sdep.Table (D).Sfile;
334
335 if F /= No_File then
336
337 -- If this is the first time we are seeing this source file,
338 -- then make a new entry in the source table.
339
340 if Get_Name_Table_Int (F) = 0 then
341 Source.Increment_Last;
342 S := Source.Last;
343 Set_Name_Table_Int (F, Int (S));
344 Source.Table (S).Sfile := F;
345 Source.Table (S).All_Timestamps_Match := True;
346
347 -- Initialize checksum fields
348
349 Source.Table (S).Checksum := Sdep.Table (D).Checksum;
350 Source.Table (S).All_Checksums_Match := True;
351
352 -- In check source files mode, try to get time stamp from file
353
354 if Opt.Check_Source_Files then
355 Stamp := Source_File_Stamp (F);
356
357 -- If we got the stamp, then set the stamp in the source
358 -- table entry and mark it as set from the source so that
359 -- it does not get subsequently changed.
360
361 if Stamp (Stamp'First) /= ' ' then
362 Source.Table (S).Stamp := Stamp;
363 Source.Table (S).Source_Found := True;
364 Source.Table (S).Stamp_File := F;
365
366 -- If we could not find the file, then the stamp is set
367 -- from the dependency table entry (to be possibly reset
368 -- if we find a later stamp in subsequent processing)
369
370 else
371 Source.Table (S).Stamp := Sdep.Table (D).Stamp;
372 Source.Table (S).Source_Found := False;
373 Source.Table (S).Stamp_File := ALIs.Table (A).Afile;
374
375 -- In All_Sources mode, flag error of file not found
376
377 if Opt.All_Sources then
378 Error_Msg_File_1 := F;
379 Error_Msg ("cannot locate {");
380 end if;
381 end if;
382
383 -- First time for this source file, but Check_Source_Files
384 -- is off, so simply initialize the stamp from the Sdep entry
385
386 else
387 Source.Table (S).Stamp := Sdep.Table (D).Stamp;
388 Source.Table (S).Source_Found := False;
389 Source.Table (S).Stamp_File := ALIs.Table (A).Afile;
390 end if;
391
392 -- Here if this is not the first time for this source file,
393 -- so that the source table entry is already constructed.
394
395 else
396 S := Source_Id (Get_Name_Table_Int (F));
397
398 -- Update checksum flag
399
400 if not Checksums_Match
401 (Sdep.Table (D).Checksum, Source.Table (S).Checksum)
402 then
403 Source.Table (S).All_Checksums_Match := False;
404 end if;
405
406 -- Check for time stamp mismatch
407
408 if Sdep.Table (D).Stamp /= Source.Table (S).Stamp then
409 Source.Table (S).All_Timestamps_Match := False;
410
411 -- When we have a time stamp mismatch, we go look for the
412 -- source file even if Check_Source_Files is false, since
413 -- if we find it, then we can use it to resolve which of the
414 -- two timestamps in the ALI files is likely to be correct.
415 -- We only look in the current directory, because when
416 -- Check_Source_Files is false, other search directories are
417 -- likely to be incorrect.
418
419 if not Check_Source_Files
420 and then Is_Regular_File (Get_Name_String (F))
421 then
422 Stamp := Source_File_Stamp (F);
423
424 if Stamp (Stamp'First) /= ' ' then
425 Source.Table (S).Stamp := Stamp;
426 Source.Table (S).Source_Found := True;
427 Source.Table (S).Stamp_File := F;
428 end if;
429 end if;
430
431 -- If the stamp in the source table entry was set from the
432 -- source file, then we do not change it (the stamp in the
433 -- source file is always taken as the "right" one).
434
435 if Source.Table (S).Source_Found then
436 null;
437
438 -- Otherwise, we have no source file available, so we guess
439 -- that the later of the two timestamps is the right one.
440 -- Note that this guess only affects which error messages
441 -- are issued later on, not correct functionality.
442
443 else
444 if Sdep.Table (D).Stamp > Source.Table (S).Stamp then
445 Source.Table (S).Stamp := Sdep.Table (D).Stamp;
446 Source.Table (S).Stamp_File := ALIs.Table (A).Afile;
447 end if;
448 end if;
449 end if;
450 end if;
451
452 -- Set the checksum value in the source table
453
454 S := Source_Id (Get_Name_Table_Int (F));
455 Source.Table (S).Checksum := Sdep.Table (D).Checksum;
456 end if;
457
458 end loop Sdep_Loop;
459 end Set_Source_Table;
460
461 ----------------------
462 -- Set_Source_Table --
463 ----------------------
464
465 procedure Set_Source_Table is
466 begin
467 for A in ALIs.First .. ALIs.Last loop
468 Set_Source_Table (A);
469 end loop;
470 end Set_Source_Table;
471
472 -------------------------
473 -- Time_Stamp_Mismatch --
474 -------------------------
475
476 function Time_Stamp_Mismatch
477 (A : ALI_Id;
478 Read_Only : Boolean := False) return File_Name_Type
479 is
480 Src : Source_Id;
481 -- Source file Id for the current Sdep entry
482
483 begin
484 for D in ALIs.Table (A).First_Sdep .. ALIs.Table (A).Last_Sdep loop
485 Src := Source_Id (Get_Name_Table_Int (Sdep.Table (D).Sfile));
486
487 if Opt.Minimal_Recompilation
488 and then Sdep.Table (D).Stamp /= Source.Table (Src).Stamp
489 then
490 -- If minimal recompilation is in action, replace the stamp
491 -- of the source file in the table if checksums match.
492
493 -- ??? It is probably worth updating the ALI file with a new
494 -- field to avoid recomputing it each time. In any case we ensure
495 -- that we don't gobble up string table space by doing a mark
496 -- release around this computation.
497
498 Stringt.Mark;
499
500 if Checksums_Match
501 (Get_File_Checksum (Sdep.Table (D).Sfile),
502 Source.Table (Src).Checksum)
503 then
504 if Verbose_Mode then
505 Write_Str (" ");
506 Write_Str (Get_Name_String (Sdep.Table (D).Sfile));
507 Write_Str (": up to date, different timestamps " &
508 "but same checksum");
509 Write_Eol;
510 end if;
511
512 Sdep.Table (D).Stamp := Source.Table (Src).Stamp;
513 end if;
514
515 Stringt.Release;
516 end if;
517
518 if (not Read_Only) or else Source.Table (Src).Source_Found then
519 if not Source.Table (Src).Source_Found
520 or else Sdep.Table (D).Stamp /= Source.Table (Src).Stamp
521 then
522 -- If -dt debug flag set, output time stamp found/expected
523
524 if Source.Table (Src).Source_Found and then Debug_Flag_T then
525 Write_Str ("Source: """);
526 Get_Name_String (Sdep.Table (D).Sfile);
527 Write_Str (Name_Buffer (1 .. Name_Len));
528 Write_Line ("""");
529
530 Write_Str (" time stamp expected: ");
531 Write_Line (String (Sdep.Table (D).Stamp));
532
533 Write_Str (" time stamp found: ");
534 Write_Line (String (Source.Table (Src).Stamp));
535 end if;
536
537 -- Return the source file
538
539 return Source.Table (Src).Sfile;
540 end if;
541 end if;
542 end loop;
543
544 return No_File;
545 end Time_Stamp_Mismatch;
546
547 end ALI.Util;