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147 | -------------------------------------------------------------------------------
-- --
-- Copyright (C) 2012-, AdaHeads K/S --
-- --
-- This is free software; you can redistribute it and/or modify it --
-- under terms of the GNU General Public License as published by the --
-- Free Software Foundation; either version 3, or (at your option) any --
-- later version. This library is distributed in the hope that it will be --
-- useful, but WITHOUT ANY WARRANTY; without even the implied warranty of --
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. --
-- You should have received a copy of the GNU General Public License and --
-- a copy of the GCC Runtime Library Exception along with this program; --
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
-- <http://www.gnu.org/licenses/>. --
-- --
-------------------------------------------------------------------------------
with Ada.Characters.Handling;
with Hex_Utilities;
package body URL_Utilities is
subtype Escape_Code is String (1 .. 2);
Not_Escaped : constant Escape_Code := " ";
function Code (C : Character) return Escape_Code;
pragma Inline (Code);
-- Returns hexadecimal code for character C
subtype ASCII_7 is Character range Character'First .. Character'Val (127);
type ASCII_7_Set is array (ASCII_7) of Escape_Code;
function Build_Hex_Escape return ASCII_7_Set;
-- Returns the table with pre-computed encoding for 7bits characters
----------------------
-- Build_Hex_Escape --
----------------------
function Build_Hex_Escape return ASCII_7_Set is
Result : ASCII_7_Set;
begin
for C in Character'Val (0) .. Character'Val (127) loop
if Ada.Strings.Maps.Is_In (C, Default_Encoding_Set) then
Result (C) := Code (C);
else
Result (C) := Not_Escaped;
end if;
end loop;
return Result;
end Build_Hex_Escape;
----------
-- Code --
----------
function Code (C : Character) return Escape_Code is
begin
return Hex_Utilities.Hex (Character'Pos (C));
end Code;
Hex_Escape : constant ASCII_7_Set := Build_Hex_Escape;
-- Limit Hex_Escape to 7bits ASCII characters only. Other ISO-8859-1 are
-- handled separately in Encode function. Space character is not processed
-- specifically, contrary to what is done in AWS.URL.
------------
-- Decode --
------------
function Decode (Str : String) return String is
Res : String (1 .. Str'Length);
K : Natural := 0;
I : Positive := Str'First;
begin
if Str = "" then
return "";
end if;
loop
K := K + 1;
if Str (I) = '%'
and then I + 2 <= Str'Last
and then Ada.Characters.Handling.Is_Hexadecimal_Digit (Str (I + 1))
and then Ada.Characters.Handling.Is_Hexadecimal_Digit (Str (I + 2))
then
Res (K) := Character'Val
(Hex_Utilities.Hex_Value (Str (I + 1 .. I + 2)));
I := I + 2;
elsif Str (I) = '+' then
-- A plus is used for spaces in forms value for example
Res (K) := ' ';
else
Res (K) := Str (I);
end if;
I := I + 1;
exit when I > Str'Last;
end loop;
return Res (1 .. K);
end Decode;
------------
-- Encode --
------------
function Encode
(Str : String;
Encoding_Set : Ada.Strings.Maps.Character_Set := Default_Encoding_Set)
return String
is
C_128 : constant Character := Character'Val (128);
Res : String (1 .. Str'Length * 3);
K : Natural := 0;
begin
for I in Str'Range loop
if Ada.Strings.Maps.Is_In (Str (I), Encoding_Set) then
-- This character must be encoded
K := K + 1;
Res (K) := '%';
K := K + 1;
if Str (I) < C_128 then
-- We keep a table for characters lower than 128 for efficiency
Res (K .. K + 1) := Hex_Escape (Str (I));
else
Res (K .. K + 1) := Code (Str (I));
end if;
K := K + 1;
else
K := K + 1;
Res (K) := Str (I);
end if;
end loop;
return Res (1 .. K);
end Encode;
end URL_Utilities;
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