| 1 |
706 |
jeremybenn |
------------------------------------------------------------------------------
|
| 2 |
|
|
-- --
|
| 3 |
|
|
-- GNAT RUN-TIME COMPONENTS --
|
| 4 |
|
|
-- --
|
| 5 |
|
|
-- A D A . S T R I N G S . U T F _ E N C O D I N G --
|
| 6 |
|
|
-- --
|
| 7 |
|
|
-- B o d y --
|
| 8 |
|
|
-- --
|
| 9 |
|
|
-- Copyright (C) 2010, Free Software Foundation, 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 3, 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. --
|
| 17 |
|
|
-- --
|
| 18 |
|
|
-- As a special exception under Section 7 of GPL version 3, you are granted --
|
| 19 |
|
|
-- additional permissions described in the GCC Runtime Library Exception, --
|
| 20 |
|
|
-- version 3.1, as published by the Free Software Foundation. --
|
| 21 |
|
|
-- --
|
| 22 |
|
|
-- You should have received a copy of the GNU General Public License and --
|
| 23 |
|
|
-- a copy of the GCC Runtime Library Exception along with this program; --
|
| 24 |
|
|
-- see the files COPYING3 and COPYING.RUNTIME respectively. If not, see --
|
| 25 |
|
|
-- <http://www.gnu.org/licenses/>. --
|
| 26 |
|
|
-- --
|
| 27 |
|
|
-- GNAT was originally developed by the GNAT team at New York University. --
|
| 28 |
|
|
-- Extensive contributions were provided by Ada Core Technologies Inc. --
|
| 29 |
|
|
-- --
|
| 30 |
|
|
------------------------------------------------------------------------------
|
| 31 |
|
|
|
| 32 |
|
|
package body Ada.Strings.UTF_Encoding is
|
| 33 |
|
|
use Interfaces;
|
| 34 |
|
|
|
| 35 |
|
|
--------------
|
| 36 |
|
|
-- Encoding --
|
| 37 |
|
|
--------------
|
| 38 |
|
|
|
| 39 |
|
|
function Encoding
|
| 40 |
|
|
(Item : UTF_String;
|
| 41 |
|
|
Default : Encoding_Scheme := UTF_8) return Encoding_Scheme
|
| 42 |
|
|
is
|
| 43 |
|
|
begin
|
| 44 |
|
|
if Item'Length >= 2 then
|
| 45 |
|
|
if Item (Item'First .. Item'First + 1) = BOM_16BE then
|
| 46 |
|
|
return UTF_16BE;
|
| 47 |
|
|
|
| 48 |
|
|
elsif Item (Item'First .. Item'First + 1) = BOM_16LE then
|
| 49 |
|
|
return UTF_16LE;
|
| 50 |
|
|
|
| 51 |
|
|
elsif Item'Length >= 3
|
| 52 |
|
|
and then Item (Item'First .. Item'First + 2) = BOM_8
|
| 53 |
|
|
then
|
| 54 |
|
|
return UTF_8;
|
| 55 |
|
|
end if;
|
| 56 |
|
|
end if;
|
| 57 |
|
|
|
| 58 |
|
|
return Default;
|
| 59 |
|
|
end Encoding;
|
| 60 |
|
|
|
| 61 |
|
|
-----------------
|
| 62 |
|
|
-- From_UTF_16 --
|
| 63 |
|
|
-----------------
|
| 64 |
|
|
|
| 65 |
|
|
function From_UTF_16
|
| 66 |
|
|
(Item : UTF_16_Wide_String;
|
| 67 |
|
|
Output_Scheme : UTF_XE_Encoding;
|
| 68 |
|
|
Output_BOM : Boolean := False) return UTF_String
|
| 69 |
|
|
is
|
| 70 |
|
|
BSpace : constant Natural := 2 * Boolean'Pos (Output_BOM);
|
| 71 |
|
|
Result : UTF_String (1 .. 2 * Item'Length + BSpace);
|
| 72 |
|
|
Len : Natural;
|
| 73 |
|
|
C : Unsigned_16;
|
| 74 |
|
|
Iptr : Natural;
|
| 75 |
|
|
|
| 76 |
|
|
begin
|
| 77 |
|
|
if Output_BOM then
|
| 78 |
|
|
Result (1 .. 2) :=
|
| 79 |
|
|
(if Output_Scheme = UTF_16BE then BOM_16BE else BOM_16LE);
|
| 80 |
|
|
Len := 2;
|
| 81 |
|
|
else
|
| 82 |
|
|
Len := 0;
|
| 83 |
|
|
end if;
|
| 84 |
|
|
|
| 85 |
|
|
-- Skip input BOM
|
| 86 |
|
|
|
| 87 |
|
|
Iptr := Item'First;
|
| 88 |
|
|
|
| 89 |
|
|
if Iptr <= Item'Last and then Item (Iptr) = BOM_16 (1) then
|
| 90 |
|
|
Iptr := Iptr + 1;
|
| 91 |
|
|
end if;
|
| 92 |
|
|
|
| 93 |
|
|
-- UTF-16BE case
|
| 94 |
|
|
|
| 95 |
|
|
if Output_Scheme = UTF_16BE then
|
| 96 |
|
|
while Iptr <= Item'Last loop
|
| 97 |
|
|
C := To_Unsigned_16 (Item (Iptr));
|
| 98 |
|
|
Result (Len + 1) := Character'Val (Shift_Right (C, 8));
|
| 99 |
|
|
Result (Len + 2) := Character'Val (C and 16#00_FF#);
|
| 100 |
|
|
Len := Len + 2;
|
| 101 |
|
|
Iptr := Iptr + 1;
|
| 102 |
|
|
end loop;
|
| 103 |
|
|
|
| 104 |
|
|
-- UTF-16LE case
|
| 105 |
|
|
|
| 106 |
|
|
else
|
| 107 |
|
|
while Iptr <= Item'Last loop
|
| 108 |
|
|
C := To_Unsigned_16 (Item (Iptr));
|
| 109 |
|
|
Result (Len + 1) := Character'Val (C and 16#00_FF#);
|
| 110 |
|
|
Result (Len + 2) := Character'Val (Shift_Right (C, 8));
|
| 111 |
|
|
Len := Len + 2;
|
| 112 |
|
|
Iptr := Iptr + 1;
|
| 113 |
|
|
end loop;
|
| 114 |
|
|
end if;
|
| 115 |
|
|
|
| 116 |
|
|
return Result (1 .. Len);
|
| 117 |
|
|
end From_UTF_16;
|
| 118 |
|
|
|
| 119 |
|
|
--------------------------
|
| 120 |
|
|
-- Raise_Encoding_Error --
|
| 121 |
|
|
--------------------------
|
| 122 |
|
|
|
| 123 |
|
|
procedure Raise_Encoding_Error (Index : Natural) is
|
| 124 |
|
|
Val : constant String := Index'Img;
|
| 125 |
|
|
begin
|
| 126 |
|
|
raise Encoding_Error with
|
| 127 |
|
|
"bad input at Item (" & Val (Val'First + 1 .. Val'Last) & ')';
|
| 128 |
|
|
end Raise_Encoding_Error;
|
| 129 |
|
|
|
| 130 |
|
|
---------------
|
| 131 |
|
|
-- To_UTF_16 --
|
| 132 |
|
|
---------------
|
| 133 |
|
|
|
| 134 |
|
|
function To_UTF_16
|
| 135 |
|
|
(Item : UTF_String;
|
| 136 |
|
|
Input_Scheme : UTF_XE_Encoding;
|
| 137 |
|
|
Output_BOM : Boolean := False) return UTF_16_Wide_String
|
| 138 |
|
|
is
|
| 139 |
|
|
Result : UTF_16_Wide_String (1 .. Item'Length / 2 + 1);
|
| 140 |
|
|
Len : Natural;
|
| 141 |
|
|
Iptr : Natural;
|
| 142 |
|
|
|
| 143 |
|
|
begin
|
| 144 |
|
|
if Item'Length mod 2 /= 0 then
|
| 145 |
|
|
raise Encoding_Error with "UTF-16BE/LE string has odd length";
|
| 146 |
|
|
end if;
|
| 147 |
|
|
|
| 148 |
|
|
-- Deal with input BOM, skip if OK, error if bad BOM
|
| 149 |
|
|
|
| 150 |
|
|
Iptr := Item'First;
|
| 151 |
|
|
|
| 152 |
|
|
if Item'Length >= 2 then
|
| 153 |
|
|
if Item (Iptr .. Iptr + 1) = BOM_16BE then
|
| 154 |
|
|
if Input_Scheme = UTF_16BE then
|
| 155 |
|
|
Iptr := Iptr + 2;
|
| 156 |
|
|
else
|
| 157 |
|
|
Raise_Encoding_Error (Iptr);
|
| 158 |
|
|
end if;
|
| 159 |
|
|
|
| 160 |
|
|
elsif Item (Iptr .. Iptr + 1) = BOM_16LE then
|
| 161 |
|
|
if Input_Scheme = UTF_16LE then
|
| 162 |
|
|
Iptr := Iptr + 2;
|
| 163 |
|
|
else
|
| 164 |
|
|
Raise_Encoding_Error (Iptr);
|
| 165 |
|
|
end if;
|
| 166 |
|
|
|
| 167 |
|
|
elsif Item'Length >= 3 and then Item (Iptr .. Iptr + 2) = BOM_8 then
|
| 168 |
|
|
Raise_Encoding_Error (Iptr);
|
| 169 |
|
|
end if;
|
| 170 |
|
|
end if;
|
| 171 |
|
|
|
| 172 |
|
|
-- Output BOM if specified
|
| 173 |
|
|
|
| 174 |
|
|
if Output_BOM then
|
| 175 |
|
|
Result (1) := BOM_16 (1);
|
| 176 |
|
|
Len := 1;
|
| 177 |
|
|
else
|
| 178 |
|
|
Len := 0;
|
| 179 |
|
|
end if;
|
| 180 |
|
|
|
| 181 |
|
|
-- UTF-16BE case
|
| 182 |
|
|
|
| 183 |
|
|
if Input_Scheme = UTF_16BE then
|
| 184 |
|
|
while Iptr < Item'Last loop
|
| 185 |
|
|
Len := Len + 1;
|
| 186 |
|
|
Result (Len) :=
|
| 187 |
|
|
Wide_Character'Val
|
| 188 |
|
|
(Character'Pos (Item (Iptr)) * 256 +
|
| 189 |
|
|
Character'Pos (Item (Iptr + 1)));
|
| 190 |
|
|
Iptr := Iptr + 2;
|
| 191 |
|
|
end loop;
|
| 192 |
|
|
|
| 193 |
|
|
-- UTF-16LE case
|
| 194 |
|
|
|
| 195 |
|
|
else
|
| 196 |
|
|
while Iptr < Item'Last loop
|
| 197 |
|
|
Len := Len + 1;
|
| 198 |
|
|
Result (Len) :=
|
| 199 |
|
|
Wide_Character'Val
|
| 200 |
|
|
(Character'Pos (Item (Iptr)) +
|
| 201 |
|
|
Character'Pos (Item (Iptr + 1)) * 256);
|
| 202 |
|
|
Iptr := Iptr + 2;
|
| 203 |
|
|
end loop;
|
| 204 |
|
|
end if;
|
| 205 |
|
|
|
| 206 |
|
|
return Result (1 .. Len);
|
| 207 |
|
|
end To_UTF_16;
|
| 208 |
|
|
|
| 209 |
|
|
end Ada.Strings.UTF_Encoding;
|
