gcc/ada/g-dirope.adb

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --            G N A T . D I R E C T O R Y _ O P E R A T I O N S             --
   6 --                                                                          --
   7 --                                 B o d y                                  --
   8 --                                                                          --
   9 --            Copyright (C) 1998-2003 Ada Core Technologies, 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,  59 Temple Place - Suite 330,  Boston, --
  20 -- MA 02111-1307, USA.                                                      --
  21 --                                                                          --
  22 -- As a special exception,  if other files  instantiate  generics from this --
  23 -- unit, or you link  this unit with other files  to produce an executable, --
  24 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  25 -- covered  by the  GNU  General  Public  License.  This exception does not --
  26 -- however invalidate  any other reasons why  the executable file  might be --
  27 -- covered by the  GNU Public License.                                      --
  28 --                                                                          --
  29 -- GNAT was originally developed  by the GNAT team at  New York University. --
  30 -- Extensive contributions were provided by Ada Core Technologies Inc.      --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 with Ada.Characters.Handling;
  35 with Ada.Strings.Fixed;
  36 with Ada.Strings.Maps;
  37 with Unchecked_Deallocation;
  38 with Unchecked_Conversion;
  39 with System;  use System;
  40
  41 with GNAT.OS_Lib;
  42
  43 package body GNAT.Directory_Operations is
  44
  45    use Ada;
  46
  47    type Dir_Type_Value is new System.Address;
  48    --  This is the low-level address directory structure as returned by the C
  49    --  opendir routine.
  50
  51    Filename_Max : constant Integer := 1024;
  52    --  1024 is the value of FILENAME_MAX in stdio.h
  53
  54    procedure Free is new
  55      Unchecked_Deallocation (Dir_Type_Value, Dir_Type);
  56
  57    ---------------
  58    -- Base_Name --
  59    ---------------
  60
  61    function Base_Name
  62      (Path   : Path_Name;
  63       Suffix : String    := "")
  64       return   String
  65    is
  66       function Get_File_Names_Case_Sensitive return Integer;
  67       pragma Import
  68         (C, Get_File_Names_Case_Sensitive,
  69          "__gnat_get_file_names_case_sensitive");
  70
  71       Case_Sensitive_File_Name : constant Boolean :=
  72                                    Get_File_Names_Case_Sensitive = 1;
  73
  74       function Basename
  75         (Path   : Path_Name;
  76          Suffix : String    := "")
  77          return String;
  78       --  This function does the job. The only difference between Basename
  79       --  and Base_Name (the parent function) is that the former is case
  80       --  sensitive, while the latter is not. Path and Suffix are adjusted
  81       --  appropriately before calling Basename under platforms where the
  82       --  file system is not case sensitive.
  83
  84       --------------
  85       -- Basename --
  86       --------------
  87
  88       function Basename
  89         (Path   : Path_Name;
  90          Suffix : String    := "")
  91          return   String
  92       is
  93          Cut_Start : Natural :=
  94                        Strings.Fixed.Index
  95                          (Path, Dir_Seps, Going => Strings.Backward);
  96          Cut_End : Natural;
  97
  98       begin
  99          --  Cut_Start point to the first basename character
 100
 101          if Cut_Start = 0 then
 102             Cut_Start := Path'First;
 103
 104          else
 105             Cut_Start := Cut_Start + 1;
 106          end if;
 107
 108          --  Cut_End point to the last basename character.
 109
 110          Cut_End := Path'Last;
 111
 112          --  If basename ends with Suffix, adjust Cut_End.
 113
 114          if Suffix /= ""
 115            and then Path (Path'Last - Suffix'Length + 1 .. Cut_End) = Suffix
 116          then
 117             Cut_End := Path'Last - Suffix'Length;
 118          end if;
 119
 120          Check_For_Standard_Dirs : declare
 121             Offset : constant Integer := Path'First - Base_Name.Path'First;
 122             BN     : constant String  :=
 123                        Base_Name.Path (Cut_Start - Offset .. Cut_End - Offset);
 124             --  Here we use Base_Name.Path to keep the original casing
 125
 126             Has_Drive_Letter : constant Boolean :=
 127                                  OS_Lib.Path_Separator /= ':';
 128             --  If Path separator is not ':' then we are on a DOS based OS
 129             --  where this character is used as a drive letter separator.
 130
 131          begin
 132             if BN = "." or else BN = ".." then
 133                return "";
 134
 135             elsif Has_Drive_Letter
 136               and then BN'Length > 2
 137               and then Characters.Handling.Is_Letter (BN (BN'First))
 138               and then BN (BN'First + 1) = ':'
 139             then
 140                --  We have a DOS drive letter prefix, remove it
 141
 142                return BN (BN'First + 2 .. BN'Last);
 143
 144             else
 145                return BN;
 146             end if;
 147          end Check_For_Standard_Dirs;
 148       end Basename;
 149
 150    --  Start processing for Base_Name
 151
 152    begin
 153       if Path'Length <= Suffix'Length then
 154          return Path;
 155       end if;
 156
 157       if Case_Sensitive_File_Name then
 158          return Basename (Path, Suffix);
 159       else
 160          return Basename
 161            (Characters.Handling.To_Lower (Path),
 162             Characters.Handling.To_Lower (Suffix));
 163       end if;
 164    end Base_Name;
 165
 166    ----------------
 167    -- Change_Dir --
 168    ----------------
 169
 170    procedure Change_Dir (Dir_Name : Dir_Name_Str) is
 171       C_Dir_Name : constant String := Dir_Name & ASCII.NUL;
 172
 173       function chdir (Dir_Name : String) return Integer;
 174       pragma Import (C, chdir, "chdir");
 175
 176    begin
 177       if chdir (C_Dir_Name) /= 0 then
 178          raise Directory_Error;
 179       end if;
 180    end Change_Dir;
 181
 182    -----------
 183    -- Close --
 184    -----------
 185
 186    procedure Close (Dir : in out Dir_Type) is
 187
 188       function closedir (Directory : System.Address) return Integer;
 189       pragma Import (C, closedir, "closedir");
 190
 191       Discard : Integer;
 192       pragma Warnings (Off, Discard);
 193
 194    begin
 195       if not Is_Open (Dir) then
 196          raise Directory_Error;
 197       end if;
 198
 199       Discard := closedir (System.Address (Dir.all));
 200       Free (Dir);
 201    end Close;
 202
 203    --------------
 204    -- Dir_Name --
 205    --------------
 206
 207    function Dir_Name (Path : Path_Name) return Dir_Name_Str is
 208       Last_DS : constant Natural :=
 209                   Strings.Fixed.Index
 210                     (Path, Dir_Seps, Going => Strings.Backward);
 211
 212    begin
 213       if Last_DS = 0 then
 214
 215          --  There is no directory separator, returns current working directory
 216
 217          return "." & Dir_Separator;
 218
 219       else
 220          return Path (Path'First .. Last_DS);
 221       end if;
 222    end Dir_Name;
 223
 224    -----------------
 225    -- Expand_Path --
 226    -----------------
 227
 228    function Expand_Path
 229      (Path : Path_Name;
 230       Mode : Environment_Style := System_Default)
 231       return Path_Name
 232    is
 233       Environment_Variable_Char : Character;
 234       pragma Import (C, Environment_Variable_Char, "__gnat_environment_char");
 235
 236       Result      : OS_Lib.String_Access := new String (1 .. 200);
 237       Result_Last : Natural := 0;
 238
 239       procedure Append (C : Character);
 240       procedure Append (S : String);
 241       --  Append to Result
 242
 243       procedure Double_Result_Size;
 244       --  Reallocate Result, doubling its size
 245
 246       function Is_Var_Prefix (C : Character) return Boolean;
 247       pragma Inline (Is_Var_Prefix);
 248
 249       procedure Read (K : in out Positive);
 250       --  Update Result while reading current Path starting at position K. If
 251       --  a variable is found, call Var below.
 252
 253       procedure Var (K : in out Positive);
 254       --  Translate variable name starting at position K with the associated
 255       --  environment value.
 256
 257       ------------
 258       -- Append --
 259       ------------
 260
 261       procedure Append (C : Character) is
 262       begin
 263          if Result_Last = Result'Last then
 264             Double_Result_Size;
 265          end if;
 266
 267          Result_Last := Result_Last + 1;
 268          Result (Result_Last) := C;
 269       end Append;
 270
 271       procedure Append (S : String) is
 272       begin
 273          while Result_Last + S'Length - 1 > Result'Last loop
 274             Double_Result_Size;
 275          end loop;
 276
 277          Result (Result_Last + 1 .. Result_Last + S'Length) := S;
 278          Result_Last := Result_Last + S'Length;
 279       end Append;
 280
 281       ------------------------
 282       -- Double_Result_Size --
 283       ------------------------
 284
 285       procedure Double_Result_Size is
 286          New_Result : constant OS_Lib.String_Access :=
 287            new String (1 .. 2 * Result'Last);
 288
 289       begin
 290          New_Result (1 .. Result_Last) := Result (1 .. Result_Last);
 291          OS_Lib.Free (Result);
 292          Result := New_Result;
 293       end Double_Result_Size;
 294
 295       -------------------
 296       -- Is_Var_Prefix --
 297       -------------------
 298
 299       function Is_Var_Prefix (C : Character) return Boolean is
 300       begin
 301          return (C = Environment_Variable_Char and then Mode = System_Default)
 302            or else
 303              (C = '$' and then (Mode = UNIX or else Mode = Both))
 304            or else
 305              (C = '%' and then (Mode = DOS or else Mode = Both));
 306       end Is_Var_Prefix;
 307
 308       ----------
 309       -- Read --
 310       ----------
 311
 312       procedure Read (K : in out Positive) is
 313          P : Character;
 314       begin
 315          For_All_Characters : loop
 316             if Is_Var_Prefix (Path (K)) then
 317                P := Path (K);
 318
 319                --  Could be a variable
 320
 321                if K < Path'Last then
 322
 323                   if Path (K + 1) = P then
 324
 325                      --  Not a variable after all, this is a double $ or %,
 326                      --  just insert one in the result string.
 327
 328                      Append (P);
 329                      K := K + 1;
 330
 331                   else
 332                      --  Let's parse the variable
 333
 334                      Var (K);
 335                   end if;
 336
 337                else
 338                   --  We have an ending $ or % sign
 339
 340                   Append (P);
 341                end if;
 342
 343             else
 344                --  This is a standard character, just add it to the result
 345
 346                Append (Path (K));
 347             end if;
 348
 349             --  Skip to next character
 350
 351             K := K + 1;
 352
 353             exit For_All_Characters when K > Path'Last;
 354          end loop For_All_Characters;
 355       end Read;
 356
 357       ---------
 358       -- Var --
 359       ---------
 360
 361       procedure Var (K : in out Positive) is
 362          P : constant Character := Path (K);
 363          T : Character;
 364          E : Positive;
 365
 366       begin
 367          K := K + 1;
 368
 369          if P = '%' or else Path (K) = '{' then
 370
 371             --  Set terminator character
 372
 373             if P = '%' then
 374                T := '%';
 375             else
 376                T := '}';
 377                K := K + 1;
 378             end if;
 379
 380             --  Look for terminator character, k point to the first character
 381             --  for the variable name.
 382
 383             E := K;
 384
 385             loop
 386                E := E + 1;
 387                exit when Path (E) = T or else E = Path'Last;
 388             end loop;
 389
 390             if Path (E) = T then
 391
 392                --  OK found, translate with environment value
 393
 394                declare
 395                   Env : OS_Lib.String_Access :=
 396                           OS_Lib.Getenv (Path (K .. E - 1));
 397
 398                begin
 399                   Append (Env.all);
 400                   OS_Lib.Free (Env);
 401                end;
 402
 403             else
 404                --  No terminator character, not a variable after all or a
 405                --  syntax error, ignore it, insert string as-is.
 406
 407                Append (P);       --  Add prefix character
 408
 409                if T = '}' then   --  If we were looking for curly bracket
 410                   Append ('{');  --  terminator, add the curly bracket
 411                end if;
 412
 413                Append (Path (K .. E));
 414             end if;
 415
 416          else
 417             --  The variable name is everything from current position to first
 418             --  non letter/digit character.
 419
 420             E := K;
 421
 422             --  Check that first chartacter is a letter
 423
 424             if Characters.Handling.Is_Letter (Path (E)) then
 425                E := E + 1;
 426
 427                Var_Name : loop
 428                   exit Var_Name when E > Path'Last;
 429
 430                   if Characters.Handling.Is_Letter (Path (E))
 431                     or else Characters.Handling.Is_Digit (Path (E))
 432                   then
 433                      E := E + 1;
 434                   else
 435                      exit Var_Name;
 436                   end if;
 437                end loop Var_Name;
 438
 439                E := E - 1;
 440
 441                declare
 442                   Env : OS_Lib.String_Access := OS_Lib.Getenv (Path (K .. E));
 443
 444                begin
 445                   Append (Env.all);
 446                   OS_Lib.Free (Env);
 447                end;
 448
 449             else
 450                --  This is not a variable after all
 451
 452                Append ('$');
 453                Append (Path (E));
 454             end if;
 455
 456          end if;
 457
 458          K := E;
 459       end Var;
 460
 461    --  Start of processing for Expand_Path
 462
 463    begin
 464       declare
 465          K : Positive := Path'First;
 466
 467       begin
 468          Read (K);
 469
 470          declare
 471             Returned_Value : constant String := Result (1 .. Result_Last);
 472
 473          begin
 474             OS_Lib.Free (Result);
 475             return Returned_Value;
 476          end;
 477       end;
 478    end Expand_Path;
 479
 480    --------------------
 481    -- File_Extension --
 482    --------------------
 483
 484    function File_Extension (Path : Path_Name) return String is
 485       First : Natural :=
 486                 Strings.Fixed.Index
 487                   (Path, Dir_Seps, Going => Strings.Backward);
 488
 489       Dot : Natural;
 490
 491    begin
 492       if First = 0 then
 493          First := Path'First;
 494       end if;
 495
 496       Dot := Strings.Fixed.Index (Path (First .. Path'Last),
 497                                   ".",
 498                                   Going => Strings.Backward);
 499
 500       if Dot = 0 or else Dot = Path'Last then
 501          return "";
 502       else
 503          return Path (Dot .. Path'Last);
 504       end if;
 505    end File_Extension;
 506
 507    ---------------
 508    -- File_Name --
 509    ---------------
 510
 511    function File_Name (Path : Path_Name) return String is
 512    begin
 513       return Base_Name (Path);
 514    end File_Name;
 515
 516    ---------------------
 517    -- Format_Pathname --
 518    ---------------------
 519
 520    function Format_Pathname
 521      (Path  : Path_Name;
 522       Style : Path_Style := System_Default)
 523       return  String
 524    is
 525       N_Path       : String   := Path;
 526       K            : Positive := N_Path'First;
 527       Prev_Dirsep  : Boolean  := False;
 528
 529    begin
 530       if Dir_Separator = '\'
 531         and then Path'Length > 1
 532         and then Path (K .. K + 1) = "\\"
 533       then
 534          if Style = UNIX then
 535             N_Path (K .. K + 1) := "//";
 536          end if;
 537
 538          K := K + 2;
 539       end if;
 540
 541       for J in K .. Path'Last loop
 542          if Strings.Maps.Is_In (Path (J), Dir_Seps) then
 543             if not Prev_Dirsep then
 544                case Style is
 545                   when UNIX           => N_Path (K) := '/';
 546                   when DOS            => N_Path (K) := '\';
 547                   when System_Default => N_Path (K) := Dir_Separator;
 548                end case;
 549
 550                K := K + 1;
 551             end if;
 552
 553             Prev_Dirsep := True;
 554
 555          else
 556             N_Path (K) := Path (J);
 557             K := K + 1;
 558             Prev_Dirsep := False;
 559          end if;
 560       end loop;
 561
 562       return N_Path (N_Path'First .. K - 1);
 563    end Format_Pathname;
 564
 565    ---------------------
 566    -- Get_Current_Dir --
 567    ---------------------
 568
 569    Max_Path : Integer;
 570    pragma Import (C, Max_Path, "__gnat_max_path_len");
 571
 572    function Get_Current_Dir return Dir_Name_Str is
 573       Current_Dir : String (1 .. Max_Path + 1);
 574       Last        : Natural;
 575
 576    begin
 577       Get_Current_Dir (Current_Dir, Last);
 578       return Current_Dir (1 .. Last);
 579    end Get_Current_Dir;
 580
 581    procedure Get_Current_Dir (Dir : out Dir_Name_Str; Last : out Natural) is
 582       Path_Len : Natural := Max_Path;
 583       Buffer   : String (Dir'First .. Dir'First + Max_Path + 1);
 584
 585       procedure Local_Get_Current_Dir
 586         (Dir    : System.Address;
 587          Length : System.Address);
 588       pragma Import (C, Local_Get_Current_Dir, "__gnat_get_current_dir");
 589
 590    begin
 591       Local_Get_Current_Dir (Buffer'Address, Path_Len'Address);
 592
 593       if Dir'Length > Path_Len then
 594          Last := Dir'First + Path_Len - 1;
 595       else
 596          Last := Dir'Last;
 597       end if;
 598
 599       Dir (Buffer'First .. Last) := Buffer (Buffer'First .. Last);
 600    end Get_Current_Dir;
 601
 602    -------------
 603    -- Is_Open --
 604    -------------
 605
 606    function Is_Open (Dir : Dir_Type) return Boolean is
 607    begin
 608       return Dir /= Null_Dir
 609         and then System.Address (Dir.all) /= System.Null_Address;
 610    end Is_Open;
 611
 612    --------------
 613    -- Make_Dir --
 614    --------------
 615
 616    procedure Make_Dir (Dir_Name : Dir_Name_Str) is
 617       C_Dir_Name : constant String := Dir_Name & ASCII.NUL;
 618
 619       function mkdir (Dir_Name : String) return Integer;
 620       pragma Import (C, mkdir, "__gnat_mkdir");
 621
 622    begin
 623       if mkdir (C_Dir_Name) /= 0 then
 624          raise Directory_Error;
 625       end if;
 626    end Make_Dir;
 627
 628    ----------
 629    -- Open --
 630    ----------
 631
 632    procedure Open
 633      (Dir      : out Dir_Type;
 634       Dir_Name : Dir_Name_Str)
 635    is
 636       C_File_Name : constant String := Dir_Name & ASCII.NUL;
 637
 638       function opendir
 639         (File_Name : String)
 640          return      Dir_Type_Value;
 641       pragma Import (C, opendir, "opendir");
 642
 643    begin
 644       Dir := new Dir_Type_Value'(opendir (C_File_Name));
 645
 646       if not Is_Open (Dir) then
 647          Free (Dir);
 648          Dir := Null_Dir;
 649          raise Directory_Error;
 650       end if;
 651    end Open;
 652
 653    ----------
 654    -- Read --
 655    ----------
 656
 657    procedure Read
 658      (Dir  : in out Dir_Type;
 659       Str  : out String;
 660       Last : out Natural)
 661    is
 662       Filename_Addr : Address;
 663       Filename_Len  : Integer;
 664
 665       Buffer : array (0 .. Filename_Max + 12) of Character;
 666       --  12 is the size of the dirent structure (see dirent.h), without the
 667       --  field for the filename.
 668
 669       function readdir_gnat
 670         (Directory : System.Address;
 671          Buffer    : System.Address)
 672          return      System.Address;
 673       pragma Import (C, readdir_gnat, "__gnat_readdir");
 674
 675       function strlen (S : Address) return Integer;
 676       pragma Import (C, strlen, "strlen");
 677
 678    begin
 679       if not Is_Open (Dir) then
 680          raise Directory_Error;
 681       end if;
 682
 683       Filename_Addr :=
 684         readdir_gnat (System.Address (Dir.all), Buffer'Address);
 685
 686       if Filename_Addr = System.Null_Address then
 687          Last := 0;
 688          return;
 689       end if;
 690
 691       Filename_Len  := strlen (Filename_Addr);
 692
 693       if Str'Length > Filename_Len then
 694          Last := Str'First + Filename_Len - 1;
 695       else
 696          Last := Str'Last;
 697       end if;
 698
 699       declare
 700          subtype Path_String is String (1 .. Filename_Len);
 701          type    Path_String_Access is access Path_String;
 702
 703          function Address_To_Access is new
 704            Unchecked_Conversion
 705              (Source => Address,
 706               Target => Path_String_Access);
 707
 708          Path_Access : constant Path_String_Access :=
 709                          Address_To_Access (Filename_Addr);
 710
 711       begin
 712          for J in Str'First .. Last loop
 713             Str (J) := Path_Access (J - Str'First + 1);
 714          end loop;
 715       end;
 716    end Read;
 717
 718    -------------------------
 719    -- Read_Is_Thread_Sage --
 720    -------------------------
 721
 722    function Read_Is_Thread_Safe return Boolean is
 723
 724       function readdir_is_thread_safe return Integer;
 725       pragma Import
 726         (C, readdir_is_thread_safe, "__gnat_readdir_is_thread_safe");
 727
 728    begin
 729       return (readdir_is_thread_safe /= 0);
 730    end Read_Is_Thread_Safe;
 731
 732    ----------------
 733    -- Remove_Dir --
 734    ----------------
 735
 736    procedure Remove_Dir
 737      (Dir_Name  : Dir_Name_Str;
 738       Recursive : Boolean := False)
 739    is
 740       C_Dir_Name  : constant String := Dir_Name & ASCII.NUL;
 741       Current_Dir : constant Dir_Name_Str := Get_Current_Dir;
 742       Last        : Integer;
 743       Str         : String (1 .. Filename_Max);
 744       Success     : Boolean;
 745       Working_Dir : Dir_Type;
 746
 747       procedure rmdir (Dir_Name : String);
 748       pragma Import (C, rmdir, "rmdir");
 749
 750    begin
 751       --  Remove the directory only if it is empty
 752
 753       if not Recursive then
 754          rmdir (C_Dir_Name);
 755
 756          if GNAT.OS_Lib.Is_Directory (Dir_Name) then
 757             raise Directory_Error;
 758          end if;
 759
 760       --  Remove directory and all files and directories that it may contain
 761
 762       else
 763          Change_Dir (Dir_Name);
 764          Open (Working_Dir, ".");
 765
 766          loop
 767             Read (Working_Dir, Str, Last);
 768             exit when Last = 0;
 769
 770             if GNAT.OS_Lib.Is_Directory (Str (1 .. Last)) then
 771                if Str (1 .. Last) /= "." and then Str (1 .. Last) /= ".." then
 772                   Remove_Dir (Str (1 .. Last), True);
 773                   Remove_Dir (Str (1 .. Last));
 774                end if;
 775
 776             else
 777                GNAT.OS_Lib.Delete_File (Str (1 .. Last), Success);
 778
 779                if not Success then
 780                   Change_Dir (Current_Dir);
 781                   raise Directory_Error;
 782                end if;
 783             end if;
 784          end loop;
 785
 786          Change_Dir (Current_Dir);
 787          Close (Working_Dir);
 788          Remove_Dir (Dir_Name);
 789       end if;
 790    end Remove_Dir;
 791
 792 end GNAT.Directory_Operations;