gcc/ada/sinput-l.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                             S I N P U T . L                              --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --          Copyright (C) 1992-2004 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 2,  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 COPYING.  If not, write --
  19 -- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, USA.                                              --
  21 --                                                                          --
  22 -- GNAT was originally developed  by the GNAT team at  New York University. --
  23 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  24 --                                                                          --
  25 ------------------------------------------------------------------------------
  26
  27 with Alloc;
  28 with Atree;    use Atree;
  29 with Debug;    use Debug;
  30 with Einfo;    use Einfo;
  31 with Errout;   use Errout;
  32 with Namet;    use Namet;
  33 with Opt;      use Opt;
  34 with Osint;    use Osint;
  35 with Output;   use Output;
  36 with Prep;     use Prep;
  37 with Prepcomp; use Prepcomp;
  38 with Scans;    use Scans;
  39 with Scn;      use Scn;
  40 with Sinfo;    use Sinfo;
  41 with System;   use System;
  42
  43 with Unchecked_Conversion;
  44
  45 package body Sinput.L is
  46
  47    Prep_Buffer : Text_Buffer_Ptr := null;
  48    --  A buffer to temporarily stored the result of preprocessing a source.
  49    --  It is only allocated if there is at least one source to preprocess.
  50
  51    Prep_Buffer_Last : Text_Ptr := 0;
  52    --  Index of the last significant character in Prep_Buffer
  53
  54    Initial_Size_Of_Prep_Buffer : constant := 10_000;
  55    --  Size of Prep_Buffer when it is first allocated
  56
  57    --  When a file is to be preprocessed and the options to list symbols
  58    --  has been selected (switch -s), Prep.List_Symbols is called with a
  59    --  "foreword", a single line indicationg what source the symbols apply to.
  60    --  The following two constant String are the start and the end of this
  61    --  foreword.
  62
  63    Foreword_Start : constant String :=
  64                       "Preprocessing Symbols for source """;
  65
  66    Foreword_End : constant String := """";
  67
  68    -----------------
  69    -- Subprograms --
  70    -----------------
  71
  72    procedure Put_Char_In_Prep_Buffer (C : Character);
  73    --  Add one character in Prep_Buffer, extending Prep_Buffer if need be.
  74    --  Used to initialize the preprocessor.
  75
  76    procedure New_EOL_In_Prep_Buffer;
  77    --  Add an LF to Prep_Buffer.
  78    --  Used to initialize the preprocessor.
  79
  80    function Load_File
  81      (N : File_Name_Type;
  82       T : Osint.File_Type) return Source_File_Index;
  83    --  Load a source file, a configuration pragmas file or a definition file
  84    --  Coding also allows preprocessing file, but not a library file ???
  85
  86    -------------------------------
  87    -- Adjust_Instantiation_Sloc --
  88    -------------------------------
  89
  90    procedure Adjust_Instantiation_Sloc (N : Node_Id; A : Sloc_Adjustment) is
  91       Loc : constant Source_Ptr := Sloc (N);
  92
  93    begin
  94       --  We only do the adjustment if the value is between the appropriate
  95       --  low and high values. It is not clear that this should ever not be
  96       --  the case, but in practice there seem to be some nodes that get
  97       --  copied twice, and this is a defence against that happening.
  98
  99       if A.Lo <= Loc and then Loc <= A.Hi then
 100          Set_Sloc (N, Loc + A.Adjust);
 101       end if;
 102    end Adjust_Instantiation_Sloc;
 103
 104    --------------------------------
 105    -- Complete_Source_File_Entry --
 106    --------------------------------
 107
 108    procedure Complete_Source_File_Entry is
 109       CSF : constant Source_File_Index := Current_Source_File;
 110
 111    begin
 112       Trim_Lines_Table (CSF);
 113       Source_File.Table (CSF).Source_Checksum := Checksum;
 114    end Complete_Source_File_Entry;
 115
 116    ---------------------------------
 117    -- Create_Instantiation_Source --
 118    ---------------------------------
 119
 120    procedure Create_Instantiation_Source
 121      (Inst_Node    : Entity_Id;
 122       Template_Id  : Entity_Id;
 123       Inlined_Body : Boolean;
 124       A            : out Sloc_Adjustment)
 125    is
 126       Dnod : constant Node_Id := Declaration_Node (Template_Id);
 127       Xold : Source_File_Index;
 128       Xnew : Source_File_Index;
 129
 130    begin
 131       Xold := Get_Source_File_Index (Sloc (Template_Id));
 132       A.Lo := Source_File.Table (Xold).Source_First;
 133       A.Hi := Source_File.Table (Xold).Source_Last;
 134
 135       Source_File.Increment_Last;
 136       Xnew := Source_File.Last;
 137
 138       Source_File.Table (Xnew)               := Source_File.Table (Xold);
 139       Source_File.Table (Xnew).Inlined_Body  := Inlined_Body;
 140       Source_File.Table (Xnew).Instantiation := Sloc (Inst_Node);
 141       Source_File.Table (Xnew).Template      := Xold;
 142
 143       --  Now we need to compute the new values of Source_First, Source_Last
 144       --  and adjust the source file pointer to have the correct virtual
 145       --  origin for the new range of values.
 146
 147       Source_File.Table (Xnew).Source_First :=
 148         Source_File.Table (Xnew - 1).Source_Last + 1;
 149       A.Adjust := Source_File.Table (Xnew).Source_First - A.Lo;
 150       Source_File.Table (Xnew).Source_Last := A.Hi + A.Adjust;
 151       Set_Source_File_Index_Table (Xnew);
 152
 153       Source_File.Table (Xnew).Sloc_Adjust :=
 154         Source_File.Table (Xold).Sloc_Adjust - A.Adjust;
 155
 156       if Debug_Flag_L then
 157          Write_Eol;
 158          Write_Str ("*** Create instantiation source for ");
 159
 160          if Nkind (Dnod) in N_Proper_Body
 161            and then Was_Originally_Stub (Dnod)
 162          then
 163             Write_Str ("subunit ");
 164
 165          elsif Ekind (Template_Id) = E_Generic_Package then
 166             if Nkind (Dnod) = N_Package_Body then
 167                Write_Str ("body of package ");
 168             else
 169                Write_Str ("spec of package ");
 170             end if;
 171
 172          elsif Ekind (Template_Id) = E_Function then
 173             Write_Str ("body of function ");
 174
 175          elsif Ekind (Template_Id) = E_Procedure then
 176             Write_Str ("body of procedure ");
 177
 178          elsif Ekind (Template_Id) = E_Generic_Function then
 179             Write_Str ("spec of function ");
 180
 181          elsif Ekind (Template_Id) = E_Generic_Procedure then
 182             Write_Str ("spec of procedure ");
 183
 184          elsif Ekind (Template_Id) = E_Package_Body then
 185             Write_Str ("body of package ");
 186
 187          else pragma Assert (Ekind (Template_Id) = E_Subprogram_Body);
 188
 189             if Nkind (Dnod) = N_Procedure_Specification then
 190                Write_Str ("body of procedure ");
 191             else
 192                Write_Str ("body of function ");
 193             end if;
 194          end if;
 195
 196          Write_Name (Chars (Template_Id));
 197          Write_Eol;
 198
 199          Write_Str ("  new source index = ");
 200          Write_Int (Int (Xnew));
 201          Write_Eol;
 202
 203          Write_Str ("  copying from file name = ");
 204          Write_Name (File_Name (Xold));
 205          Write_Eol;
 206
 207          Write_Str ("  old source index = ");
 208          Write_Int (Int (Xold));
 209          Write_Eol;
 210
 211          Write_Str ("  old lo = ");
 212          Write_Int (Int (A.Lo));
 213          Write_Eol;
 214
 215          Write_Str ("  old hi = ");
 216          Write_Int (Int (A.Hi));
 217          Write_Eol;
 218
 219          Write_Str ("  new lo = ");
 220          Write_Int (Int (Source_File.Table (Xnew).Source_First));
 221          Write_Eol;
 222
 223          Write_Str ("  new hi = ");
 224          Write_Int (Int (Source_File.Table (Xnew).Source_Last));
 225          Write_Eol;
 226
 227          Write_Str ("  adjustment factor = ");
 228          Write_Int (Int (A.Adjust));
 229          Write_Eol;
 230
 231          Write_Str ("  instantiation location: ");
 232          Write_Location (Sloc (Inst_Node));
 233          Write_Eol;
 234       end if;
 235
 236       --  For a given character in the source, a higher subscript will be
 237       --  used to access the instantiation, which means that the virtual
 238       --  origin must have a corresponding lower value. We compute this
 239       --  new origin by taking the address of the appropriate adjusted
 240       --  element in the old array. Since this adjusted element will be
 241       --  at a negative subscript, we must suppress checks.
 242
 243       declare
 244          pragma Suppress (All_Checks);
 245
 246          pragma Warnings (Off);
 247          --  This unchecked conversion is aliasing safe, since it is never
 248          --  used to create improperly aliased pointer values.
 249
 250          function To_Source_Buffer_Ptr is new
 251            Unchecked_Conversion (Address, Source_Buffer_Ptr);
 252
 253          pragma Warnings (On);
 254
 255       begin
 256          Source_File.Table (Xnew).Source_Text :=
 257            To_Source_Buffer_Ptr
 258              (Source_File.Table (Xold).Source_Text (-A.Adjust)'Address);
 259       end;
 260    end Create_Instantiation_Source;
 261
 262    ----------------------
 263    -- Load_Config_File --
 264    ----------------------
 265
 266    function Load_Config_File
 267      (N : File_Name_Type) return Source_File_Index
 268    is
 269    begin
 270       return Load_File (N, Osint.Config);
 271    end Load_Config_File;
 272
 273    --------------------------
 274    -- Load_Definition_File --
 275    --------------------------
 276
 277    function Load_Definition_File
 278      (N : File_Name_Type) return Source_File_Index
 279    is
 280    begin
 281       return Load_File (N, Osint.Definition);
 282    end Load_Definition_File;
 283
 284    ---------------
 285    -- Load_File --
 286    ---------------
 287
 288    function Load_File
 289      (N : File_Name_Type;
 290       T : Osint.File_Type) return Source_File_Index
 291    is
 292       Src : Source_Buffer_Ptr;
 293       X   : Source_File_Index;
 294       Lo  : Source_Ptr;
 295       Hi  : Source_Ptr;
 296
 297       Preprocessing_Needed : Boolean := False;
 298
 299    begin
 300       --  If already there, don't need to reload file. An exception occurs
 301       --  in multiple unit per file mode. It would be nice in this case to
 302       --  share the same source file for each unit, but this leads to many
 303       --  difficulties with assumptions (e.g. in the body of lib), that a
 304       --  unit can be found by locating its source file index. Since we do
 305       --  not expect much use of this mode, it's no big deal to waste a bit
 306       --  of space and time by reading and storing the source multiple times.
 307
 308       if Multiple_Unit_Index = 0 then
 309          for J in 1 .. Source_File.Last loop
 310             if Source_File.Table (J).File_Name = N then
 311                return J;
 312             end if;
 313          end loop;
 314       end if;
 315
 316       --  Here we must build a new entry in the file table
 317
 318       --  But first, we must check if a source needs to be preprocessed,
 319       --  because we may have to load and parse a definition file, and we want
 320       --  to do that before we load the source, so that the buffer of the
 321       --  source will be the last created, and we will be able to replace it
 322       --  and modify Hi without stepping on another buffer.
 323
 324       if T = Osint.Source then
 325          Prepare_To_Preprocess
 326            (Source => N, Preprocessing_Needed => Preprocessing_Needed);
 327       end if;
 328
 329       Source_File.Increment_Last;
 330       X := Source_File.Last;
 331
 332       if X = Source_File.First then
 333          Lo := First_Source_Ptr;
 334       else
 335          Lo := Source_File.Table (X - 1).Source_Last + 1;
 336       end if;
 337
 338       Osint.Read_Source_File (N, Lo, Hi, Src, T);
 339
 340       if Src = null then
 341          Source_File.Decrement_Last;
 342          return No_Source_File;
 343
 344       else
 345          if Debug_Flag_L then
 346             Write_Eol;
 347             Write_Str ("*** Build source file table entry, Index = ");
 348             Write_Int (Int (X));
 349             Write_Str (", file name = ");
 350             Write_Name (N);
 351             Write_Eol;
 352             Write_Str ("  lo = ");
 353             Write_Int (Int (Lo));
 354             Write_Eol;
 355             Write_Str ("  hi = ");
 356             Write_Int (Int (Hi));
 357             Write_Eol;
 358
 359             Write_Str ("  first 10 chars -->");
 360
 361             declare
 362                procedure Wchar (C : Character);
 363                --  Writes character or ? for control character
 364
 365                procedure Wchar (C : Character) is
 366                begin
 367                   if C < ' ' or C in ASCII.DEL .. Character'Val (16#9F#) then
 368                      Write_Char ('?');
 369                   else
 370                      Write_Char (C);
 371                   end if;
 372                end Wchar;
 373
 374             begin
 375                for J in Lo .. Lo + 9 loop
 376                   Wchar (Src (J));
 377                end loop;
 378
 379                Write_Str ("<--");
 380                Write_Eol;
 381
 382                Write_Str ("  last 10 chars  -->");
 383
 384                for J in Hi - 10 .. Hi - 1 loop
 385                   Wchar (Src (J));
 386                end loop;
 387
 388                Write_Str ("<--");
 389                Write_Eol;
 390
 391                if Src (Hi) /= EOF then
 392                   Write_Str ("  error: no EOF at end");
 393                   Write_Eol;
 394                end if;
 395             end;
 396          end if;
 397
 398          declare
 399             S         : Source_File_Record renames Source_File.Table (X);
 400             File_Type : Type_Of_File;
 401
 402          begin
 403             case T is
 404                when Osint.Source =>
 405                   File_Type := Sinput.Src;
 406
 407                when Osint.Library =>
 408                   raise Program_Error;
 409
 410                when Osint.Config =>
 411                   File_Type := Sinput.Config;
 412
 413                when Osint.Definition =>
 414                   File_Type := Def;
 415
 416                when Osint.Preprocessing_Data =>
 417                   File_Type := Preproc;
 418             end case;
 419
 420             S := (Debug_Source_Name   => N,
 421                   File_Name           => N,
 422                   File_Type           => File_Type,
 423                   First_Mapped_Line   => No_Line_Number,
 424                   Full_Debug_Name     => Osint.Full_Source_Name,
 425                   Full_File_Name      => Osint.Full_Source_Name,
 426                   Full_Ref_Name       => Osint.Full_Source_Name,
 427                   Identifier_Casing   => Unknown,
 428                   Inlined_Body        => False,
 429                   Instantiation       => No_Location,
 430                   Keyword_Casing      => Unknown,
 431                   Last_Source_Line    => 1,
 432                   License             => Unknown,
 433                   Lines_Table         => null,
 434                   Lines_Table_Max     => 1,
 435                   Logical_Lines_Table => null,
 436                   Num_SRef_Pragmas    => 0,
 437                   Reference_Name      => N,
 438                   Sloc_Adjust         => 0,
 439                   Source_Checksum     => 0,
 440                   Source_First        => Lo,
 441                   Source_Last         => Hi,
 442                   Source_Text         => Src,
 443                   Template            => No_Source_File,
 444                   Time_Stamp          => Osint.Current_Source_File_Stamp);
 445
 446             Alloc_Line_Tables (S, Opt.Table_Factor * Alloc.Lines_Initial);
 447             S.Lines_Table (1) := Lo;
 448          end;
 449
 450          --  Preprocess the source if it needs to be preprocessed
 451
 452          if Preprocessing_Needed then
 453             if Opt.List_Preprocessing_Symbols then
 454                Get_Name_String (N);
 455
 456                declare
 457                   Foreword : String (1 .. Foreword_Start'Length +
 458                                           Name_Len + Foreword_End'Length);
 459
 460                begin
 461                   Foreword (1 .. Foreword_Start'Length) := Foreword_Start;
 462                   Foreword (Foreword_Start'Length + 1 ..
 463                               Foreword_Start'Length + Name_Len) :=
 464                     Name_Buffer (1 .. Name_Len);
 465                   Foreword (Foreword'Last - Foreword_End'Length + 1 ..
 466                               Foreword'Last) := Foreword_End;
 467                   Prep.List_Symbols (Foreword);
 468                end;
 469             end if;
 470
 471             declare
 472                T : constant Nat := Total_Errors_Detected;
 473                --  Used to check if there were errors during preprocessing
 474
 475             begin
 476                --  If this is the first time we preprocess a source, allocate
 477                --  the preprocessing buffer.
 478
 479                if Prep_Buffer = null then
 480                   Prep_Buffer :=
 481                     new Text_Buffer (1 .. Initial_Size_Of_Prep_Buffer);
 482                end if;
 483
 484                --  Make sure the preprocessing buffer is empty
 485
 486                Prep_Buffer_Last := 0;
 487
 488                --  Initialize the preprocessor
 489
 490                Prep.Initialize
 491                  (Error_Msg         => Errout.Error_Msg'Access,
 492                   Scan              => Scn.Scanner.Scan'Access,
 493                   Set_Ignore_Errors => Errout.Set_Ignore_Errors'Access,
 494                   Put_Char          => Put_Char_In_Prep_Buffer'Access,
 495                   New_EOL           => New_EOL_In_Prep_Buffer'Access);
 496
 497                --  Initialize the scanner and set its behavior for
 498                --  preprocessing, then preprocess.
 499
 500                Scn.Scanner.Initialize_Scanner (No_Unit, X);
 501
 502                Scn.Scanner.Set_Special_Character ('#');
 503                Scn.Scanner.Set_Special_Character ('$');
 504                Scn.Scanner.Set_End_Of_Line_As_Token (True);
 505
 506                Preprocess;
 507
 508                --  Reset the scanner to its standard behavior
 509
 510                Scn.Scanner.Reset_Special_Characters;
 511                Scn.Scanner.Set_End_Of_Line_As_Token (False);
 512
 513                --  If there were errors during preprocessing, record an
 514                --  error at the start of the file, and do not change the
 515                --  source buffer.
 516
 517                if T /= Total_Errors_Detected then
 518                   Errout.Error_Msg
 519                     ("file could not be successfully preprocessed", Lo);
 520                   return No_Source_File;
 521
 522                else
 523                   --  Set the new value of Hi
 524
 525                   Hi := Lo + Source_Ptr (Prep_Buffer_Last);
 526
 527                   --  Create the new source buffer
 528
 529                   declare
 530                      subtype Actual_Source_Buffer is Source_Buffer (Lo .. Hi);
 531                      --  Physical buffer allocated
 532
 533                      type Actual_Source_Ptr is access Actual_Source_Buffer;
 534                      --  This is the pointer type for the physical buffer
 535                      --  allocated.
 536
 537                      Actual_Ptr : constant Actual_Source_Ptr :=
 538                                     new Actual_Source_Buffer;
 539                      --  And this is the actual physical buffer
 540
 541                   begin
 542                      Actual_Ptr (Lo .. Hi - 1) :=
 543                        Prep_Buffer (1 .. Prep_Buffer_Last);
 544                      Actual_Ptr (Hi) := EOF;
 545
 546                      --  Now we need to work out the proper virtual origin
 547                      --  pointer to return. This is exactly
 548                      --  Actual_Ptr (0)'Address, but we have to be careful to
 549                      --  suppress checks to compute this address.
 550
 551                      declare
 552                         pragma Suppress (All_Checks);
 553
 554                         pragma Warnings (Off);
 555                         --  This unchecked conversion is aliasing safe, since
 556                         --  it is never used to create improperly aliased
 557                         --  pointer values.
 558
 559                         function To_Source_Buffer_Ptr is new
 560                           Unchecked_Conversion (Address, Source_Buffer_Ptr);
 561
 562                         pragma Warnings (On);
 563
 564                      begin
 565                         Src := To_Source_Buffer_Ptr (Actual_Ptr (0)'Address);
 566
 567                         --  Record in the table the new source buffer and the
 568                         --  new value of Hi.
 569
 570                         Source_File.Table (X).Source_Text := Src;
 571                         Source_File.Table (X).Source_Last := Hi;
 572
 573                         --  Reset Last_Line to 1, because the lines do not
 574                         --  have neccessarily the same starts and lengths.
 575
 576                         Source_File.Table (X).Last_Source_Line := 1;
 577                      end;
 578                   end;
 579                end if;
 580             end;
 581          end if;
 582
 583          Set_Source_File_Index_Table (X);
 584          return X;
 585       end if;
 586    end Load_File;
 587
 588    ----------------------------------
 589    -- Load_Preprocessing_Data_File --
 590    ----------------------------------
 591
 592    function Load_Preprocessing_Data_File
 593      (N : File_Name_Type) return Source_File_Index
 594    is
 595    begin
 596       return Load_File (N, Osint.Preprocessing_Data);
 597    end Load_Preprocessing_Data_File;
 598
 599    ----------------------
 600    -- Load_Source_File --
 601    ----------------------
 602
 603    function Load_Source_File
 604      (N : File_Name_Type) return Source_File_Index
 605    is
 606    begin
 607       return Load_File (N, Osint.Source);
 608    end Load_Source_File;
 609
 610    ----------------------------
 611    -- New_EOL_In_Prep_Buffer --
 612    ----------------------------
 613
 614    procedure New_EOL_In_Prep_Buffer is
 615    begin
 616       Put_Char_In_Prep_Buffer (ASCII.LF);
 617    end New_EOL_In_Prep_Buffer;
 618
 619    -----------------------------
 620    -- Put_Char_In_Prep_Buffer --
 621    -----------------------------
 622
 623    procedure Put_Char_In_Prep_Buffer (C : Character) is
 624    begin
 625       --  If preprocessing buffer is not large enough, double it
 626
 627       if Prep_Buffer_Last = Prep_Buffer'Last then
 628          declare
 629             New_Prep_Buffer : constant Text_Buffer_Ptr :=
 630               new Text_Buffer (1 .. 2 * Prep_Buffer_Last);
 631
 632          begin
 633             New_Prep_Buffer (Prep_Buffer'Range) := Prep_Buffer.all;
 634             Free (Prep_Buffer);
 635             Prep_Buffer := New_Prep_Buffer;
 636          end;
 637       end if;
 638
 639       Prep_Buffer_Last := Prep_Buffer_Last + 1;
 640       Prep_Buffer (Prep_Buffer_Last) := C;
 641    end Put_Char_In_Prep_Buffer;
 642
 643    ----------------------------
 644    -- Source_File_Is_Subunit --
 645    ----------------------------
 646
 647    function Source_File_Is_Subunit (X : Source_File_Index) return Boolean is
 648    begin
 649       Initialize_Scanner (No_Unit, X);
 650
 651       --  We scan past junk to the first interesting compilation unit
 652       --  token, to see if it is SEPARATE. We ignore WITH keywords during
 653       --  this and also PRIVATE. The reason for ignoring PRIVATE is that
 654       --  it handles some error situations, and also it is possible that
 655       --  a PRIVATE WITH feature might be approved some time in the future.
 656
 657       while Token = Tok_With
 658         or else Token = Tok_Private
 659         or else (Token not in Token_Class_Cunit and then Token /= Tok_EOF)
 660       loop
 661          Scan;
 662       end loop;
 663
 664       return Token = Tok_Separate;
 665    end Source_File_Is_Subunit;
 666
 667 end Sinput.L;