gcc/ada/g-encstr.ads

   1 ------------------------------------------------------------------------------
   2 --                                                                          --
   3 --                         GNAT RUN-TIME COMPONENTS                         --
   4 --                                                                          --
   5 --                    G N A T . E N C O D E _ S T R I N G                   --
   6 --                                                                          --
   7 --                                 S p e c                                  --
   8 --                                                                          --
   9 --                     Copyright (C) 2007-2008, AdaCore                     --
  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 --  This generic package provides utility routines for converting from
  35 --  Wide_String or Wide_Wide_String to encoded String using a specified
  36 --  encoding convention, which is supplied as the generic parameter. If
  37 --  this parameter is a known at compile time constant (e.g. a constant
  38 --  defined in System.WCh_Con), the instantiation is specialized so that
  39 --  it applies only to this specified coding.
  40
  41 --  Note: this package is only about encoding sequences of 16- or 32-bit
  42 --  characters into a sequence of 8-bit codes. It knows nothing at all about
  43 --  the character encodings being used for the input Wide_Character and
  44 --  Wide_Wide_Character values, although some of the encoding methods (notably
  45 --  JIS and EUC) have built in assumptions about the range of possible input
  46 --  code values. Most often the input will be Unicode/ISO-10646 as specified by
  47 --  the Ada RM, but this package does not make any assumptions about the
  48 --  character coding, and in the case of UTF-8 all possible code values can be
  49 --  encoded. See also the packages Ada.Wide_[Wide_]Characters.Unicode for
  50 --  unicode specific functions.
  51
  52 --  Note on brackets encoding (WCEM_Brackets). On input, upper half characters
  53 --  can be represented as ["hh"] but the routines in this package will only use
  54 --  brackets encodings for codes higher than 16#FF#, so upper half characters
  55 --  will be output as single Character values.
  56
  57 with System.WCh_Con;
  58
  59 generic
  60    Encoding_Method : System.WCh_Con.WC_Encoding_Method;
  61
  62 package GNAT.Encode_String is
  63    pragma Pure;
  64
  65    function Encode_Wide_String (S : Wide_String) return String;
  66    pragma Inline (Encode_Wide_String);
  67    --  Encode the given Wide_String, returning a String encoded using the
  68    --  given encoding method. Constraint_Error will be raised if the encoding
  69    --  method cannot accommodate the input data.
  70
  71    procedure Encode_Wide_String
  72      (S      : Wide_String;
  73       Result : out String;
  74       Length : out Natural);
  75    --  Encode the given Wide_String, storing the encoded string in Result,
  76    --  with Length being set to the length of the encoded string. The caller
  77    --  must ensure that Result is long enough (see useful constants defined
  78    --  in System.WCh_Con: WC_Longest_Sequence, WC_Longest_Sequences). If the
  79    --  length of Result is insufficient Constraint_Error will be raised.
  80    --  Constraint_Error will also be raised if the encoding method cannot
  81    --  accommodate the input data.
  82
  83    function Encode_Wide_Wide_String (S : Wide_Wide_String) return String;
  84    pragma Inline (Encode_Wide_Wide_String);
  85    --  Same as above function but for Wide_Wide_String input
  86
  87    procedure Encode_Wide_Wide_String
  88      (S      : Wide_Wide_String;
  89       Result : out String;
  90       Length : out Natural);
  91    --  Same as above procedure, but for Wide_Wide_String input
  92
  93    procedure Encode_Wide_Character
  94      (Char   : Wide_Character;
  95       Result : in out String;
  96       Ptr    : in out Natural);
  97    pragma Inline (Encode_Wide_Character);
  98    --  This is a lower level procedure that encodes the single character Char.
  99    --  The output is stored in Result starting at Result (Ptr), and Ptr is
 100    --  updated past the stored value. Constraint_Error is raised if Result
 101    --  is not long enough to accommodate the result, or if the encoding method
 102    --  specified does not accommodate the input character value, or if Ptr is
 103    --  outside the bounds of the Result string.
 104
 105    procedure Encode_Wide_Wide_Character
 106      (Char   : Wide_Wide_Character;
 107       Result : in out String;
 108       Ptr    : in out Natural);
 109    --  Same as above procedure but with Wide_Wide_Character input
 110
 111 end GNAT.Encode_String;