diff options
Diffstat (limited to 'gcc/ada/a-stuten.adb')
| -rw-r--r-- | gcc/ada/a-stuten.adb | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/gcc/ada/a-stuten.adb b/gcc/ada/a-stuten.adb new file mode 100644 index 000000000..fc669b56e --- /dev/null +++ b/gcc/ada/a-stuten.adb @@ -0,0 +1,209 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- A D A . S T R I N G S . U T F _ E N C O D I N G -- +-- -- +-- B o d y -- +-- -- +-- Copyright (C) 2010, Free Software Foundation, Inc. -- +-- -- +-- GNAT is free software; you can redistribute it and/or modify it under -- +-- terms of the GNU General Public License as published by the Free Soft- -- +-- ware Foundation; either version 3, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. -- +-- -- +-- As a special exception under Section 7 of GPL version 3, you are granted -- +-- additional permissions described in the GCC Runtime Library Exception, -- +-- version 3.1, as published by the Free Software Foundation. -- +-- -- +-- 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/>. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +package body Ada.Strings.UTF_Encoding is + use Interfaces; + + -------------- + -- Encoding -- + -------------- + + function Encoding + (Item : UTF_String; + Default : Encoding_Scheme := UTF_8) return Encoding_Scheme + is + begin + if Item'Length >= 2 then + if Item (Item'First .. Item'First + 1) = BOM_16BE then + return UTF_16BE; + + elsif Item (Item'First .. Item'First + 1) = BOM_16LE then + return UTF_16LE; + + elsif Item'Length >= 3 + and then Item (Item'First .. Item'First + 2) = BOM_8 + then + return UTF_8; + end if; + end if; + + return Default; + end Encoding; + + ----------------- + -- From_UTF_16 -- + ----------------- + + function From_UTF_16 + (Item : UTF_16_Wide_String; + Output_Scheme : UTF_XE_Encoding; + Output_BOM : Boolean := False) return UTF_String + is + BSpace : constant Natural := 2 * Boolean'Pos (Output_BOM); + Result : UTF_String (1 .. 2 * Item'Length + BSpace); + Len : Natural; + C : Unsigned_16; + Iptr : Natural; + + begin + if Output_BOM then + Result (1 .. 2) := + (if Output_Scheme = UTF_16BE then BOM_16BE else BOM_16LE); + Len := 2; + else + Len := 0; + end if; + + -- Skip input BOM + + Iptr := Item'First; + + if Iptr <= Item'Last and then Item (Iptr) = BOM_16 (1) then + Iptr := Iptr + 1; + end if; + + -- UTF-16BE case + + if Output_Scheme = UTF_16BE then + while Iptr <= Item'Last loop + C := To_Unsigned_16 (Item (Iptr)); + Result (Len + 1) := Character'Val (Shift_Right (C, 8)); + Result (Len + 2) := Character'Val (C and 16#00_FF#); + Len := Len + 2; + Iptr := Iptr + 1; + end loop; + + -- UTF-16LE case + + else + while Iptr <= Item'Last loop + C := To_Unsigned_16 (Item (Iptr)); + Result (Len + 1) := Character'Val (C and 16#00_FF#); + Result (Len + 2) := Character'Val (Shift_Right (C, 8)); + Len := Len + 2; + Iptr := Iptr + 1; + end loop; + end if; + + return Result (1 .. Len); + end From_UTF_16; + + -------------------------- + -- Raise_Encoding_Error -- + -------------------------- + + procedure Raise_Encoding_Error (Index : Natural) is + Val : constant String := Index'Img; + begin + raise Encoding_Error with + "bad input at Item (" & Val (Val'First + 1 .. Val'Last) & ')'; + end Raise_Encoding_Error; + + --------------- + -- To_UTF_16 -- + --------------- + + function To_UTF_16 + (Item : UTF_String; + Input_Scheme : UTF_XE_Encoding; + Output_BOM : Boolean := False) return UTF_16_Wide_String + is + Result : UTF_16_Wide_String (1 .. Item'Length / 2 + 1); + Len : Natural; + Iptr : Natural; + + begin + if Item'Length mod 2 /= 0 then + raise Encoding_Error with "UTF-16BE/LE string has odd length"; + end if; + + -- Deal with input BOM, skip if OK, error if bad BOM + + Iptr := Item'First; + + if Item'Length >= 2 then + if Item (Iptr .. Iptr + 1) = BOM_16BE then + if Input_Scheme = UTF_16BE then + Iptr := Iptr + 2; + else + Raise_Encoding_Error (Iptr); + end if; + + elsif Item (Iptr .. Iptr + 1) = BOM_16LE then + if Input_Scheme = UTF_16LE then + Iptr := Iptr + 2; + else + Raise_Encoding_Error (Iptr); + end if; + + elsif Item'Length >= 3 and then Item (Iptr .. Iptr + 2) = BOM_8 then + Raise_Encoding_Error (Iptr); + end if; + end if; + + -- Output BOM if specified + + if Output_BOM then + Result (1) := BOM_16 (1); + Len := 1; + else + Len := 0; + end if; + + -- UTF-16BE case + + if Input_Scheme = UTF_16BE then + while Iptr < Item'Last loop + Len := Len + 1; + Result (Len) := + Wide_Character'Val + (Character'Pos (Item (Iptr)) * 256 + + Character'Pos (Item (Iptr + 1))); + Iptr := Iptr + 2; + end loop; + + -- UTF-16LE case + + else + while Iptr < Item'Last loop + Len := Len + 1; + Result (Len) := + Wide_Character'Val + (Character'Pos (Item (Iptr)) + + Character'Pos (Item (Iptr + 1)) * 256); + Iptr := Iptr + 2; + end loop; + end if; + + return Result (1 .. Len); + end To_UTF_16; + +end Ada.Strings.UTF_Encoding; |