gcc/ada/g-comlin.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT COMPILER COMPONENTS                         --
   4 --                                                                          --
   5 --                    G N A T . C O M M A N D _ L I N E                     --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                                                                          --
  10 --            Copyright (C) 1999-2002 Ada Core Technologies, Inc.           --
  11 --                                                                          --
  12 -- GNAT is free software;  you can  redistribute it  and/or modify it under --
  13 -- terms of the  GNU General Public License as published  by the Free Soft- --
  14 -- ware  Foundation;  either version 2,  or (at your option) any later ver- --
  15 -- sion.  GNAT is distributed in the hope that it will be useful, but WITH- --
  16 -- OUT ANY WARRANTY;  without even the  implied warranty of MERCHANTABILITY --
  17 -- or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License --
  18 -- for  more details.  You should have  received  a copy of the GNU General --
  19 -- Public License  distributed with GNAT;  see file COPYING.  If not, write --
  20 -- to  the Free Software Foundation,  59 Temple Place - Suite 330,  Boston, --
  21 -- MA 02111-1307, USA.                                                      --
  22 --                                                                          --
  23 -- As a special exception,  if other files  instantiate  generics from this --
  24 -- unit, or you link  this unit with other files  to produce an executable, --
  25 -- this  unit  does not  by itself cause  the resulting  executable  to  be --
  26 -- covered  by the  GNU  General  Public  License.  This exception does not --
  27 -- however invalidate  any other reasons why  the executable file  might be --
  28 -- covered by the  GNU Public License.                                      --
  29 --                                                                          --
  30 -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com).   --
  31 --                                                                          --
  32 ------------------------------------------------------------------------------
  33
  34 --  High level package for command line parsing
  35
  36 --  This package provides an interface to Ada.Command_Line, to do the
  37 --  parsing of command line arguments. Here is a small usage example:
  38
  39 --  begin
  40 --     loop
  41 --        case Getopt ("a b: ad") is  -- Accepts '-a', '-ad', or '-b argument'
  42 --           when ASCII.NUL => exit;
  43
  44 --           when 'a' =>
  45 --                 if Full_Switch = "a" then
  46 --                    Put_Line ("Got a");
  47 --                 else
  48 --                    Put_Line ("Got ad");
  49 --                 end if;
  50
  51 --           when 'b' =>
  52 --              Put_Line ("Got b + " & Parameter);
  53 --
  54 --           when others =>
  55 --              raise Program_Error;         -- cannot occur!
  56 --        end case;
  57 --     end loop;
  58
  59 --     loop
  60 --        declare
  61 --           S : constant String := Get_Argument (Do_Expansion => True);
  62 --        begin
  63 --           exit when S'Length = 0;
  64 --           Put_Line ("Got " & S);
  65 --        end;
  66 --     end loop;
  67 --
  68 --  exception
  69 --     when Invalid_Switch    => Put_Line ("Invalid Switch " & Full_Switch);
  70 --     when Invalid_Parameter => Put_Line ("No parameter for " & Full_Switch);
  71 --  end;
  72
  73 --  A more complicated example would involve the use of sections for the
  74 --  switches, as for instance in gnatmake. These sections are separated by
  75 --  special switches, chosen by the programer. Each section act as a
  76 --  command line of its own.
  77
  78 --  begin
  79 --     Initialize_Option_Scan ('-', False, "largs bargs cargs");
  80 --     loop
  81 --        --  Same loop as above to get switches and arguments
  82 --     end loop;
  83
  84 --     Goto_Section ("bargs");
  85 --     loop
  86 --        --  Same loop as above to get switches and arguments
  87 --        --  The supports switches in Get_Opt might be different
  88 --     end loop;
  89
  90 --     Goto_Section ("cargs");
  91 --     loop
  92 --        --  Same loop as above to get switches and arguments
  93 --        --  The supports switches in Get_Opt might be different
  94 --     end loop;
  95 --  end;
  96
  97 with GNAT.Directory_Operations;
  98 with GNAT.Regexp;
  99
 100 package GNAT.Command_Line is
 101
 102    procedure Initialize_Option_Scan
 103      (Switch_Char              : Character := '-';
 104       Stop_At_First_Non_Switch : Boolean := False;
 105       Section_Delimiters       : String := "");
 106    --  This procedure resets the internal state of the package to prepare
 107    --  to rescan the parameters. It need not (but may be) called before the
 108    --  first use of Getopt, but it must be called if you want to start
 109    --  rescanning the command line parameters from the start. The optional
 110    --  parameter Switch_Char can be used to reset the switch character,
 111    --  e.g. to '/' for use in DOS-like systems. The optional parameter
 112    --  Stop_At_First_Non_Switch indicates if Getopt is to look for switches
 113    --  on the whole command line, or if it has to stop as soon as a
 114    --  non-switch argument is found.
 115    --
 116    --  Example:
 117    --
 118    --      Arguments: my_application file1 -c
 119    --
 120    --      if Stop_At_First_Non_Switch is False, then -c will be considered
 121    --      as a switch (returned by getopt), otherwise it will be considered
 122    --      as a normal argument (returned by Get_Argument).
 123    --
 124    --  if SECTION_DELIMITERS is set, then every following subprogram
 125    --  (Getopt and Get_Argument) will only operate within a section, which
 126    --  is delimited by any of these delimiters or the end of the command line.
 127    --
 128    --  Example:
 129    --      Initialize_Option_Scan ("largs bargs cargs");
 130    --
 131    --      Arguments on command line : my_application -c -bargs -d -e -largs -f
 132    --      This line is made of three section, the first one is the default one
 133    --      and includes only the '-c' switch, the second one is between -bargs
 134    --      and -largs and includes '-d -e' and the last one includes '-f'
 135
 136    procedure Goto_Section (Name : String := "");
 137    --  Change the current section. The next Getopt of Get_Argument will
 138    --  start looking at the beginning of the section. An empty name ("")
 139    --  refers to the first section between the program name and the first
 140    --  section delimiter.
 141    --  If the section does not exist, then Invalid_Section is raised.
 142
 143    function Full_Switch return String;
 144    --  Returns the full name of the last switch found (Getopt only returns
 145    --  the first character)
 146
 147    function Getopt (Switches : String) return Character;
 148    --  This function moves to the next switch on the command line (defined
 149    --  as a switch character followed by a character within Switches,
 150    --  casing being significant). The result returned is the first
 151    --  character of the particular switch located. If there are no more
 152    --  switches in the current section, returns ASCII.NUL. The switches
 153    --  need not be separated by spaces (they can be concatenated if they do
 154    --  not require an argument, e.g. -ab is the same as two separate
 155    --  arguments -a -b).
 156    --
 157    --  Switches is a string of all the possible switches, separated by a
 158    --  space. A switch can be followed by one of the following characters :
 159    --
 160    --   ':'  The switch requires a parameter. There can optionally be a space
 161    --        on the command line between the switch and its parameter
 162    --   '='  The switch requires a parameter. There can either be a '=' or a
 163    --        space on the command line between the switch and its parameter
 164    --   '!'  The switch requires a parameter, but there can be no space on the
 165    --        command line between the switch and its parameter
 166    --   '?'  The switch may have an optional parameter. There can no space
 167    --        between the switch and its argument
 168    --        ex/ if Switches has the following value : "a? b"
 169    --            The command line can be :
 170    --             -afoo    :  -a switch with 'foo' parameter
 171    --             -a foo   :  -a switch and another element on the
 172    --                           command line 'foo', returned by Get_Argument
 173    --
 174    --     Example: if Switches is "-a: -aO:", you can have the following
 175    --              command lines :
 176    --                -aarg    :  'a' switch with 'arg' parameter
 177    --                -a arg   :  'a' switch with 'arg' parameter
 178    --                -aOarg   :  'aO' switch with 'arg' parameter
 179    --                -aO arg  :  'aO' switch with 'arg' parameter
 180    --
 181    --    Example:
 182    --
 183    --       Getopt ("a b: ac ad?")
 184    --
 185    --         accept either 'a' or 'ac' with no argument,
 186    --         accept 'b' with a required argument
 187    --         accept 'ad' with an optional argument
 188    --
 189    --  If the first item in switches is '*', then Getopt will catch
 190    --  every element on the command line that was not caught by any other
 191    --  switch. The character returned by GetOpt is '*'
 192    --
 193    --    Example
 194    --       Getopt ("* a b")
 195    --       If the command line is '-a -c toto.o -b', GetOpt will return
 196    --       successively 'a', '*', '*' and 'b'. When '*' is returnd,
 197    --       Full_Switch returns the corresponding item on the command line.
 198    --
 199    --
 200    --  When Getopt encounters an invalid switch, it raises the exception
 201    --  Invalid_Switch and sets Full_Switch to return the invalid switch.
 202    --  When Getopt can not find the parameter associated with a switch, it
 203    --  raises Invalid_Parameter, and sets Full_Switch to return the invalid
 204    --  switch character.
 205    --
 206    --  Note: in case of ambiguity, e.g. switches a ab abc, then the longest
 207    --  matching switch is returned.
 208    --
 209    --  Arbitrary characters are allowed for switches, although it is
 210    --  strongly recommanded to use only letters and digits for portability
 211    --  reasons.
 212
 213    function Get_Argument (Do_Expansion : Boolean := False) return String;
 214    --  Returns the next element in the command line which is not a switch.
 215    --  This function should not be called before Getopt has returned
 216    --  ASCII.NUL.
 217    --
 218    --  If Expansion is True, then the parameter on the command
 219    --  line will considered as filename with wild cards, and will be
 220    --  expanded. The matching file names will be returned one at a time.
 221    --  When there are no more arguments on the command line, this function
 222    --  returns an empty string. This is useful in non-Unix systems for
 223    --  obtaining normal expansion of wild card references.
 224
 225    function Parameter return String;
 226    --  Returns parameter associated with the last switch returned by Getopt.
 227    --  If no parameter was associated with the last switch, or no previous
 228    --  call has been made to Get_Argument, raises Invalid_Parameter.
 229    --  If the last switch was associated with an optional argument and this
 230    --  argument was not found on the command line, Parameter returns an empty
 231    --  string
 232
 233    type Expansion_Iterator is limited private;
 234    --  Type used during expansion of file names
 235
 236    procedure Start_Expansion
 237      (Iterator     : out Expansion_Iterator;
 238       Pattern      : String;
 239       Directory    : String := "";
 240       Basic_Regexp : Boolean := True);
 241    --  Initialize a wild card expansion. The next calls to Expansion will
 242    --  return the next file name in Directory which match Pattern (Pattern
 243    --  is a regular expression, using only the Unix shell and DOS syntax if
 244    --  Basic_Regexp is True). When Directory is an empty string, the current
 245    --  directory is searched.
 246    --
 247    --  Pattern may contains directory separators (as in "src/*/*.ada").
 248    --  Subdirectories of Directory will also be searched, up to one
 249    --  hundred levels deep.
 250    --
 251    --  When Start_Expansion has been called, function Expansion should be
 252    --  called repetitively until it returns an empty string, before
 253    --  Start_Expansion can be called again with the same Expansion_Iterator
 254    --  variable.
 255
 256    function Expansion (Iterator : Expansion_Iterator) return String;
 257    --  Return the next file in the directory matching the parameters given
 258    --  to Start_Expansion and updates Iterator to point to the next entry.
 259    --  Returns an empty string when there are no more files in the directory
 260    --  and its subdirectories.
 261    --
 262    --  If Expansion is called again after an empty string has been returned,
 263    --  then the exception GNAT.Directory_Operations.Directory_Error is raised.
 264
 265    Invalid_Section : exception;
 266    --  Raised when an invalid section is selected by Goto_Section
 267
 268    Invalid_Switch : exception;
 269    --  Raised when an invalid switch is detected in the command line
 270
 271    Invalid_Parameter : exception;
 272    --  Raised when a parameter is missing, or an attempt is made to obtain
 273    --  a parameter for a switch that does not allow a parameter
 274
 275 private
 276
 277    Max_Depth : constant := 100;
 278    --  Maximum depth of subdirectories
 279
 280    Max_Path_Length : constant := 1024;
 281    --  Maximum length of relative path
 282
 283    type Depth is range 1 .. Max_Depth;
 284
 285    type Level is record
 286       Name_Last : Natural := 0;
 287       Dir       : GNAT.Directory_Operations.Dir_Type;
 288    end record;
 289
 290    type Level_Array is array (Depth) of Level;
 291
 292    type Expansion_Iterator is limited record
 293       Start : Positive := 1;
 294       --  Position of the first character of the relative path to check
 295       --  against the pattern.
 296
 297       Dir_Name : String (1 .. Max_Path_Length);
 298
 299       Current_Depth : Depth := 1;
 300
 301       Levels : Level_Array;
 302
 303       Regexp : GNAT.Regexp.Regexp;
 304       --  Regular expression built with the pattern
 305
 306       Maximum_Depth : Depth := 1;
 307       --  The maximum depth of directories, reflecting the number of
 308       --  directory separators in the pattern.
 309
 310    end record;
 311
 312 end GNAT.Command_Line;