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) 1998-2005 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,  51  Franklin  Street,  Fifth  Floor, --
  20 -- Boston, MA 02110-1301, 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
  38 with Unchecked_Deallocation;
  39 with Unchecked_Conversion;
  40
  41 with System;      use System;
  42 with System.CRTL; use System.CRTL;
  43
  44 with GNAT.OS_Lib;
  45
  46 package body GNAT.Directory_Operations is
  47
  48    use Ada;
  49
  50    type Dir_Type_Value is new System.Address;
  51    --  This is the low-level address directory structure as returned by the C
  52    --  opendir routine.
  53
  54    Filename_Max : constant Integer := 1024;
  55    --  1024 is the value of FILENAME_MAX in stdio.h
  56
  57    procedure Free is new
  58      Unchecked_Deallocation (Dir_Type_Value, Dir_Type);
  59
  60    ---------------
  61    -- Base_Name --
  62    ---------------
  63
  64    function Base_Name
  65      (Path   : Path_Name;
  66       Suffix : String := "") return String
  67    is
  68       function Get_File_Names_Case_Sensitive return Integer;
  69       pragma Import
  70         (C, Get_File_Names_Case_Sensitive,
  71          "__gnat_get_file_names_case_sensitive");
  72
  73       Case_Sensitive_File_Name : constant Boolean :=
  74                                    Get_File_Names_Case_Sensitive = 1;
  75
  76       function Basename
  77         (Path   : Path_Name;
  78          Suffix : String := "") return String;
  79       --  This function does the job. The only difference between Basename
  80       --  and Base_Name (the parent function) is that the former is case
  81       --  sensitive, while the latter is not. Path and Suffix are adjusted
  82       --  appropriately before calling Basename under platforms where the
  83       --  file system is not case sensitive.
  84
  85       --------------
  86       -- Basename --
  87       --------------
  88
  89       function Basename
  90         (Path   : Path_Name;
  91          Suffix : String    := "") 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       Discard : Integer;
 188       pragma Warnings (Off, Discard);
 189
 190    begin
 191       if not Is_Open (Dir) then
 192          raise Directory_Error;
 193       end if;
 194
 195       Discard := closedir (DIRs (Dir.all));
 196       Free (Dir);
 197    end Close;
 198
 199    --------------
 200    -- Dir_Name --
 201    --------------
 202
 203    function Dir_Name (Path : Path_Name) return Dir_Name_Str is
 204       Last_DS : constant Natural :=
 205                   Strings.Fixed.Index
 206                     (Path, Dir_Seps, Going => Strings.Backward);
 207
 208    begin
 209       if Last_DS = 0 then
 210
 211          --  There is no directory separator, returns current working directory
 212
 213          return "." & Dir_Separator;
 214
 215       else
 216          return Path (Path'First .. Last_DS);
 217       end if;
 218    end Dir_Name;
 219
 220    -----------------
 221    -- Expand_Path --
 222    -----------------
 223
 224    function Expand_Path
 225      (Path : Path_Name;
 226       Mode : Environment_Style := System_Default) return Path_Name
 227    is
 228       Environment_Variable_Char : Character;
 229       pragma Import (C, Environment_Variable_Char, "__gnat_environment_char");
 230
 231       Result      : OS_Lib.String_Access := new String (1 .. 200);
 232       Result_Last : Natural := 0;
 233
 234       procedure Append (C : Character);
 235       procedure Append (S : String);
 236       --  Append to Result
 237
 238       procedure Double_Result_Size;
 239       --  Reallocate Result, doubling its size
 240
 241       function Is_Var_Prefix (C : Character) return Boolean;
 242       pragma Inline (Is_Var_Prefix);
 243
 244       procedure Read (K : in out Positive);
 245       --  Update Result while reading current Path starting at position K. If
 246       --  a variable is found, call Var below.
 247
 248       procedure Var (K : in out Positive);
 249       --  Translate variable name starting at position K with the associated
 250       --  environment value.
 251
 252       ------------
 253       -- Append --
 254       ------------
 255
 256       procedure Append (C : Character) is
 257       begin
 258          if Result_Last = Result'Last then
 259             Double_Result_Size;
 260          end if;
 261
 262          Result_Last := Result_Last + 1;
 263          Result (Result_Last) := C;
 264       end Append;
 265
 266       procedure Append (S : String) is
 267       begin
 268          while Result_Last + S'Length - 1 > Result'Last loop
 269             Double_Result_Size;
 270          end loop;
 271
 272          Result (Result_Last + 1 .. Result_Last + S'Length) := S;
 273          Result_Last := Result_Last + S'Length;
 274       end Append;
 275
 276       ------------------------
 277       -- Double_Result_Size --
 278       ------------------------
 279
 280       procedure Double_Result_Size is
 281          New_Result : constant OS_Lib.String_Access :=
 282            new String (1 .. 2 * Result'Last);
 283
 284       begin
 285          New_Result (1 .. Result_Last) := Result (1 .. Result_Last);
 286          OS_Lib.Free (Result);
 287          Result := New_Result;
 288       end Double_Result_Size;
 289
 290       -------------------
 291       -- Is_Var_Prefix --
 292       -------------------
 293
 294       function Is_Var_Prefix (C : Character) return Boolean is
 295       begin
 296          return (C = Environment_Variable_Char and then Mode = System_Default)
 297            or else
 298              (C = '$' and then (Mode = UNIX or else Mode = Both))
 299            or else
 300              (C = '%' and then (Mode = DOS or else Mode = Both));
 301       end Is_Var_Prefix;
 302
 303       ----------
 304       -- Read --
 305       ----------
 306
 307       procedure Read (K : in out Positive) is
 308          P : Character;
 309       begin
 310          For_All_Characters : loop
 311             if Is_Var_Prefix (Path (K)) then
 312                P := Path (K);
 313
 314                --  Could be a variable
 315
 316                if K < Path'Last then
 317
 318                   if Path (K + 1) = P then
 319
 320                      --  Not a variable after all, this is a double $ or %,
 321                      --  just insert one in the result string.
 322
 323                      Append (P);
 324                      K := K + 1;
 325
 326                   else
 327                      --  Let's parse the variable
 328
 329                      Var (K);
 330                   end if;
 331
 332                else
 333                   --  We have an ending $ or % sign
 334
 335                   Append (P);
 336                end if;
 337
 338             else
 339                --  This is a standard character, just add it to the result
 340
 341                Append (Path (K));
 342             end if;
 343
 344             --  Skip to next character
 345
 346             K := K + 1;
 347
 348             exit For_All_Characters when K > Path'Last;
 349          end loop For_All_Characters;
 350       end Read;
 351
 352       ---------
 353       -- Var --
 354       ---------
 355
 356       procedure Var (K : in out Positive) is
 357          P : constant Character := Path (K);
 358          T : Character;
 359          E : Positive;
 360
 361       begin
 362          K := K + 1;
 363
 364          if P = '%' or else Path (K) = '{' then
 365
 366             --  Set terminator character
 367
 368             if P = '%' then
 369                T := '%';
 370             else
 371                T := '}';
 372                K := K + 1;
 373             end if;
 374
 375             --  Look for terminator character, k point to the first character
 376             --  for the variable name.
 377
 378             E := K;
 379
 380             loop
 381                E := E + 1;
 382                exit when Path (E) = T or else E = Path'Last;
 383             end loop;
 384
 385             if Path (E) = T then
 386
 387                --  OK found, translate with environment value
 388
 389                declare
 390                   Env : OS_Lib.String_Access :=
 391                           OS_Lib.Getenv (Path (K .. E - 1));
 392
 393                begin
 394                   Append (Env.all);
 395                   OS_Lib.Free (Env);
 396                end;
 397
 398             else
 399                --  No terminator character, not a variable after all or a
 400                --  syntax error, ignore it, insert string as-is.
 401
 402                Append (P);       --  Add prefix character
 403
 404                if T = '}' then   --  If we were looking for curly bracket
 405                   Append ('{');  --  terminator, add the curly bracket
 406                end if;
 407
 408                Append (Path (K .. E));
 409             end if;
 410
 411          else
 412             --  The variable name is everything from current position to first
 413             --  non letter/digit character.
 414
 415             E := K;
 416
 417             --  Check that first chartacter is a letter
 418
 419             if Characters.Handling.Is_Letter (Path (E)) then
 420                E := E + 1;
 421
 422                Var_Name : loop
 423                   exit Var_Name when E > Path'Last;
 424
 425                   if Characters.Handling.Is_Letter (Path (E))
 426                     or else Characters.Handling.Is_Digit (Path (E))
 427                   then
 428                      E := E + 1;
 429                   else
 430                      exit Var_Name;
 431                   end if;
 432                end loop Var_Name;
 433
 434                E := E - 1;
 435
 436                declare
 437                   Env : OS_Lib.String_Access := OS_Lib.Getenv (Path (K .. E));
 438
 439                begin
 440                   Append (Env.all);
 441                   OS_Lib.Free (Env);
 442                end;
 443
 444             else
 445                --  This is not a variable after all
 446
 447                Append ('$');
 448                Append (Path (E));
 449             end if;
 450
 451          end if;
 452
 453          K := E;
 454       end Var;
 455
 456    --  Start of processing for Expand_Path
 457
 458    begin
 459       declare
 460          K : Positive := Path'First;
 461
 462       begin
 463          Read (K);
 464
 465          declare
 466             Returned_Value : constant String := Result (1 .. Result_Last);
 467
 468          begin
 469             OS_Lib.Free (Result);
 470             return Returned_Value;
 471          end;
 472       end;
 473    end Expand_Path;
 474
 475    --------------------
 476    -- File_Extension --
 477    --------------------
 478
 479    function File_Extension (Path : Path_Name) return String is
 480       First : Natural :=
 481                 Strings.Fixed.Index
 482                   (Path, Dir_Seps, Going => Strings.Backward);
 483
 484       Dot : Natural;
 485
 486    begin
 487       if First = 0 then
 488          First := Path'First;
 489       end if;
 490
 491       Dot := Strings.Fixed.Index (Path (First .. Path'Last),
 492                                   ".",
 493                                   Going => Strings.Backward);
 494
 495       if Dot = 0 or else Dot = Path'Last then
 496          return "";
 497       else
 498          return Path (Dot .. Path'Last);
 499       end if;
 500    end File_Extension;
 501
 502    ---------------
 503    -- File_Name --
 504    ---------------
 505
 506    function File_Name (Path : Path_Name) return String is
 507    begin
 508       return Base_Name (Path);
 509    end File_Name;
 510
 511    ---------------------
 512    -- Format_Pathname --
 513    ---------------------
 514
 515    function Format_Pathname
 516      (Path  : Path_Name;
 517       Style : Path_Style := System_Default) return String
 518    is
 519       N_Path       : String   := Path;
 520       K            : Positive := N_Path'First;
 521       Prev_Dirsep  : Boolean  := False;
 522
 523    begin
 524       if Dir_Separator = '\'
 525         and then Path'Length > 1
 526         and then Path (K .. K + 1) = "\\"
 527       then
 528          if Style = UNIX then
 529             N_Path (K .. K + 1) := "//";
 530          end if;
 531
 532          K := K + 2;
 533       end if;
 534
 535       for J in K .. Path'Last loop
 536          if Strings.Maps.Is_In (Path (J), Dir_Seps) then
 537             if not Prev_Dirsep then
 538                case Style is
 539                   when UNIX           => N_Path (K) := '/';
 540                   when DOS            => N_Path (K) := '\';
 541                   when System_Default => N_Path (K) := Dir_Separator;
 542                end case;
 543
 544                K := K + 1;
 545             end if;
 546
 547             Prev_Dirsep := True;
 548
 549          else
 550             N_Path (K) := Path (J);
 551             K := K + 1;
 552             Prev_Dirsep := False;
 553          end if;
 554       end loop;
 555
 556       return N_Path (N_Path'First .. K - 1);
 557    end Format_Pathname;
 558
 559    ---------------------
 560    -- Get_Current_Dir --
 561    ---------------------
 562
 563    Max_Path : Integer;
 564    pragma Import (C, Max_Path, "__gnat_max_path_len");
 565
 566    function Get_Current_Dir return Dir_Name_Str is
 567       Current_Dir : String (1 .. Max_Path + 1);
 568       Last        : Natural;
 569
 570    begin
 571       Get_Current_Dir (Current_Dir, Last);
 572       return Current_Dir (1 .. Last);
 573    end Get_Current_Dir;
 574
 575    procedure Get_Current_Dir (Dir : out Dir_Name_Str; Last : out Natural) is
 576       Path_Len : Natural := Max_Path;
 577       Buffer   : String (Dir'First .. Dir'First + Max_Path + 1);
 578
 579       procedure Local_Get_Current_Dir
 580         (Dir    : System.Address;
 581          Length : System.Address);
 582       pragma Import (C, Local_Get_Current_Dir, "__gnat_get_current_dir");
 583
 584    begin
 585       Local_Get_Current_Dir (Buffer'Address, Path_Len'Address);
 586
 587       if Dir'Length > Path_Len then
 588          Last := Dir'First + Path_Len - 1;
 589       else
 590          Last := Dir'Last;
 591       end if;
 592
 593       Dir (Buffer'First .. Last) := Buffer (Buffer'First .. Last);
 594    end Get_Current_Dir;
 595
 596    -------------
 597    -- Is_Open --
 598    -------------
 599
 600    function Is_Open (Dir : Dir_Type) return Boolean is
 601    begin
 602       return Dir /= Null_Dir
 603         and then System.Address (Dir.all) /= System.Null_Address;
 604    end Is_Open;
 605
 606    --------------
 607    -- Make_Dir --
 608    --------------
 609
 610    procedure Make_Dir (Dir_Name : Dir_Name_Str) is
 611       C_Dir_Name : constant String := Dir_Name & ASCII.NUL;
 612
 613       function mkdir (Dir_Name : String) return Integer;
 614       pragma Import (C, mkdir, "__gnat_mkdir");
 615
 616    begin
 617       if mkdir (C_Dir_Name) /= 0 then
 618          raise Directory_Error;
 619       end if;
 620    end Make_Dir;
 621
 622    ----------
 623    -- Open --
 624    ----------
 625
 626    procedure Open
 627      (Dir      : out Dir_Type;
 628       Dir_Name : Dir_Name_Str)
 629    is
 630       C_File_Name : constant String := Dir_Name & ASCII.NUL;
 631
 632    begin
 633       Dir := new Dir_Type_Value'(Dir_Type_Value (opendir (C_File_Name)));
 634
 635       if not Is_Open (Dir) then
 636          Free (Dir);
 637          Dir := Null_Dir;
 638          raise Directory_Error;
 639       end if;
 640    end Open;
 641
 642    ----------
 643    -- Read --
 644    ----------
 645
 646    procedure Read
 647      (Dir  : in out Dir_Type;
 648       Str  : out String;
 649       Last : out Natural)
 650    is
 651       Filename_Addr : Address;
 652       Filename_Len  : Integer;
 653
 654       Buffer : array (0 .. Filename_Max + 12) of Character;
 655       --  12 is the size of the dirent structure (see dirent.h), without the
 656       --  field for the filename.
 657
 658       function readdir_gnat
 659         (Directory : System.Address;
 660          Buffer    : System.Address) return System.Address;
 661       pragma Import (C, readdir_gnat, "__gnat_readdir");
 662
 663       function strlen (S : Address) return Integer;
 664       pragma Import (C, strlen, "strlen");
 665
 666    begin
 667       if not Is_Open (Dir) then
 668          raise Directory_Error;
 669       end if;
 670
 671       Filename_Addr :=
 672         readdir_gnat (System.Address (Dir.all), Buffer'Address);
 673
 674       if Filename_Addr = System.Null_Address then
 675          Last := 0;
 676          return;
 677       end if;
 678
 679       Filename_Len  := strlen (Filename_Addr);
 680
 681       if Str'Length > Filename_Len then
 682          Last := Str'First + Filename_Len - 1;
 683       else
 684          Last := Str'Last;
 685       end if;
 686
 687       declare
 688          subtype Path_String is String (1 .. Filename_Len);
 689          type    Path_String_Access is access Path_String;
 690
 691          function Address_To_Access is new
 692            Unchecked_Conversion
 693              (Source => Address,
 694               Target => Path_String_Access);
 695
 696          Path_Access : constant Path_String_Access :=
 697                          Address_To_Access (Filename_Addr);
 698
 699       begin
 700          for J in Str'First .. Last loop
 701             Str (J) := Path_Access (J - Str'First + 1);
 702          end loop;
 703       end;
 704    end Read;
 705
 706    -------------------------
 707    -- Read_Is_Thread_Sage --
 708    -------------------------
 709
 710    function Read_Is_Thread_Safe return Boolean is
 711
 712       function readdir_is_thread_safe return Integer;
 713       pragma Import
 714         (C, readdir_is_thread_safe, "__gnat_readdir_is_thread_safe");
 715
 716    begin
 717       return (readdir_is_thread_safe /= 0);
 718    end Read_Is_Thread_Safe;
 719
 720    ----------------
 721    -- Remove_Dir --
 722    ----------------
 723
 724    procedure Remove_Dir
 725      (Dir_Name  : Dir_Name_Str;
 726       Recursive : Boolean := False)
 727    is
 728       C_Dir_Name  : constant String := Dir_Name & ASCII.NUL;
 729       Current_Dir : constant Dir_Name_Str := Get_Current_Dir;
 730       Last        : Integer;
 731       Str         : String (1 .. Filename_Max);
 732       Success     : Boolean;
 733       Working_Dir : Dir_Type;
 734
 735    begin
 736       --  Remove the directory only if it is empty
 737
 738       if not Recursive then
 739          rmdir (C_Dir_Name);
 740
 741          if GNAT.OS_Lib.Is_Directory (Dir_Name) then
 742             raise Directory_Error;
 743          end if;
 744
 745       --  Remove directory and all files and directories that it may contain
 746
 747       else
 748          Change_Dir (Dir_Name);
 749          Open (Working_Dir, ".");
 750
 751          loop
 752             Read (Working_Dir, Str, Last);
 753             exit when Last = 0;
 754
 755             if GNAT.OS_Lib.Is_Directory (Str (1 .. Last)) then
 756                if Str (1 .. Last) /= "." and then Str (1 .. Last) /= ".." then
 757                   Remove_Dir (Str (1 .. Last), True);
 758                   Remove_Dir (Str (1 .. Last));
 759                end if;
 760
 761             else
 762                GNAT.OS_Lib.Delete_File (Str (1 .. Last), Success);
 763
 764                if not Success then
 765                   Change_Dir (Current_Dir);
 766                   raise Directory_Error;
 767                end if;
 768             end if;
 769          end loop;
 770
 771          Change_Dir (Current_Dir);
 772          Close (Working_Dir);
 773          Remove_Dir (Dir_Name);
 774       end if;
 775    end Remove_Dir;
 776
 777 end GNAT.Directory_Operations;