2010-10-11 Robert Dewar <dewar@adacore.com>

	* a-textio.adb: Minor reformatting

2010-10-11  Robert Dewar  <dewar@adacore.com>

	* a-suesen.ads, a-suenst.ads,
	a-suesen.adb, a-suenst.adb,
	a-suewse.adb, a-suewst.adb,
	a-suewse.ads, a-suewst.ads,
	a-suezse.ads, a-suezst.ads,
	a-suezse.adb, a-suezst.adb: New name for string encoding packages.
	* impunit.adb: New names for string encoding units
	* Makefile.rtl: New names for string encoding units
	* rtsfind.ads: Minor code reorganization.

2010-10-11  Ed Schonberg  <schonberg@adacore.com>

	* exp_ch5.adb: Code clean up.

2010-10-11  Ed Schonberg  <schonberg@adacore.com>

	* sem_ch6.adb (Check_Limited_Return): Specialize warning on limited
	returns when in a generic context.
	(Analyze_Function_Return): ditto.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@165276 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 341 insertions, 0 deletions

diff --git a/gcc/ada/a-suenst.adb b/gcc/ada/a-suenst.adb
new file mode 100755
index 00000000000..d4207ed3e30
--- /dev/null
+++ b/gcc/ada/a-suenst.adb
@@ -0,0 +1,341 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--                     ADA.STRINGS.UTF_ENCODING.STRINGS                     --
+--                                                                          --
+--                                 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.Strings is
+   use Interfaces;
+
+   ------------
+   -- Decode --
+   ------------
+
+   --  Decode UTF-8/UTF-16BE/UTF-16LE input to String
+
+   function Decode
+     (Item         : UTF_String;
+      Input_Scheme : Encoding_Scheme) return String
+   is
+   begin
+      if Input_Scheme = UTF_8 then
+         return Decode (Item);
+      else
+         return Decode (To_UTF_16 (Item, Input_Scheme));
+      end if;
+   end Decode;
+
+   --  Decode UTF-8 input to String
+
+   function Decode (Item : UTF_8_String) return String is
+      Result : String (1 .. Item'Length);
+      --  Result string (worst case is same length as input)
+
+      Len : Natural := 0;
+      --  Length of result stored so far
+
+      Iptr : Natural;
+      --  Input Item pointer
+
+      C : Unsigned_8;
+      R : Unsigned_16;
+
+      procedure Get_Continuation;
+      --  Reads a continuation byte of the form 10xxxxxx, shifts R left
+      --  by 6 bits, and or's in the xxxxxx to the low order 6 bits. On
+      --  return Ptr is incremented. Raises exceptioon if continuation
+      --  byte does not exist or is invalid.
+
+      ----------------------
+      -- Get_Continuation --
+      ----------------------
+
+      procedure Get_Continuation is
+      begin
+         if Iptr > Item'Last then
+            Raise_Encoding_Error (Iptr - 1);
+
+         else
+            C := To_Unsigned_8 (Item (Iptr));
+            Iptr := Iptr + 1;
+
+            if C not in 2#10_000000# .. 2#10_111111# then
+               Raise_Encoding_Error (Iptr - 1);
+            else
+               R := Shift_Left (R, 6) or Unsigned_16 (C and 2#00_111111#);
+            end if;
+         end if;
+      end Get_Continuation;
+
+   --  Start of processing for Decode
+
+   begin
+      Iptr := Item'First;
+
+      --  Skip BOM at start
+
+      if Item'Length >= 3
+        and then Item (Iptr .. Iptr + 2) = BOM_8
+      then
+         Iptr := Iptr + 3;
+
+      --  Error if bad BOM
+
+      elsif Item'Length >= 2
+        and then (Item (Iptr .. Iptr + 1) = BOM_16BE
+                    or else
+                  Item (Iptr .. Iptr + 1) = BOM_16LE)
+      then
+         Raise_Encoding_Error (Iptr);
+      end if;
+
+      while Iptr <= Item'Last loop
+         C := To_Unsigned_8 (Item (Iptr));
+         Iptr := Iptr + 1;
+
+         --  Codes in the range 16#00# - 16#7F# are represented as
+         --    0xxxxxxx
+
+         if C <= 16#7F# then
+            R := Unsigned_16 (C);
+
+         --  No initial code can be of the form 10xxxxxx. Such codes are used
+         --  only for continuations.
+
+         elsif C <= 2#10_111111# then
+            Raise_Encoding_Error (Iptr - 1);
+
+         --  Codes in the range 16#80# - 16#7FF# are represented as
+         --    110yyyxx 10xxxxxx
+
+         elsif C <= 2#110_11111# then
+            R := Unsigned_16 (C and 2#000_11111#);
+            Get_Continuation;
+
+         --  Codes in the range 16#800# - 16#FFFF# are represented as
+         --    1110yyyy 10yyyyxx 10xxxxxx
+
+         --  Such codes are out of range for type Character
+
+         --  Codes in the range 16#10000# - 16#10FFFF# are represented as
+         --    11110zzz 10zzyyyy 10yyyyxx 10xxxxxx
+
+         --  Such codes are out of range for Wide_String output
+
+         --  Thus all remaining cases raise Encoding_Error
+
+         else
+            Raise_Encoding_Error (Iptr - 1);
+         end if;
+
+         Len := Len + 1;
+         Result (Len) := Character'Val (R);
+      end loop;
+
+      return Result (1 .. Len);
+   end Decode;
+
+   --  Decode UTF-16 input to String
+
+   function Decode (Item : UTF_16_Wide_String) return String is
+      Result : String (1 .. Item'Length);
+      --  Result is same length as input (possibly minus 1 if BOM present)
+
+      Len : Natural := 0;
+      --  Length of result
+
+      Iptr : Natural;
+      --  Index of next Item element
+
+      C : Unsigned_16;
+
+   begin
+      --  Skip UTF-16 BOM at start
+
+      Iptr := Item'First;
+
+      if Item'Length > 0 and then Item (Iptr) = BOM_16 (1) then
+         Iptr := Iptr + 1;
+      end if;
+
+      --  Loop through input characters
+
+      while Iptr <= Item'Last loop
+         C := To_Unsigned_16 (Item (Iptr));
+         Iptr := Iptr + 1;
+
+         --  Codes in the range 16#0000#..16#00FF# represent their own value
+
+         if C <= 16#00FF# then
+            Len := Len + 1;
+            Result (Len) := Character'Val (C);
+
+         --  All other codes are invalid, either they are invalid UTF-16
+         --  encoding sequences, or they represent values that are out of
+         --  range for type Character.
+
+         else
+            Raise_Encoding_Error (Iptr - 1);
+         end if;
+      end loop;
+
+      return Result (1 .. Len);
+   end Decode;
+
+   ------------
+   -- Encode --
+   ------------
+
+   --  Encode String in UTF-8, UTF-16BE or UTF-16LE
+
+   function Encode
+     (Item          : String;
+      Output_Scheme : Encoding_Scheme;
+      Output_BOM    : Boolean  := False) return UTF_String
+   is
+   begin
+      --  Case of UTF_8
+
+      if Output_Scheme = UTF_8 then
+         return Encode (Item, Output_BOM);
+
+      --  Case of UTF_16LE or UTF_16BE, use UTF-16 intermediary
+
+      else
+         return From_UTF_16 (UTF_16_Wide_String'(Encode (Item)),
+                             Output_Scheme, Output_BOM);
+      end if;
+   end Encode;
+
+   --  Encode String in UTF-8
+
+   function Encode
+     (Item       : String;
+      Output_BOM : Boolean  := False) return UTF_8_String
+   is
+      Result : UTF_8_String (1 .. 3 * Item'Length + 3);
+      --  Worst case is three bytes per input byte + space for BOM
+
+      Len : Natural;
+      --  Number of output codes stored in Result
+
+      C : Unsigned_8;
+      --  Single input character
+
+      procedure Store (C : Unsigned_8);
+      pragma Inline (Store);
+      --  Store one output code, C is in the range 0 .. 255
+
+      -----------
+      -- Store --
+      -----------
+
+      procedure Store (C : Unsigned_8) is
+      begin
+         Len := Len + 1;
+         Result (Len) := Character'Val (C);
+      end Store;
+
+   --  Start of processing for UTF8_Encode
+
+   begin
+      --  Output BOM if required
+
+      if Output_BOM then
+         Result (1 .. 3) := BOM_8;
+         Len := 3;
+      else
+         Len := 0;
+      end if;
+
+      --  Loop through characters of input
+
+      for J in Item'Range loop
+         C := To_Unsigned_8 (Item (J));
+
+         --  Codes in the range 16#00# - 16#7F# are represented as
+         --    0xxxxxxx
+
+         if C <= 16#7F# then
+            Store (C);
+
+         --  Codes in the range 16#80# - 16#7FF# are represented as
+         --    110yyyxx 10xxxxxx
+
+         --  For type character of course, the limit is 16#FF# in any case
+
+         else
+            Store (2#110_00000# or Shift_Right (C, 6));
+            Store (2#10_000000# or (C and 2#00_111111#));
+         end if;
+      end loop;
+
+      return Result (1 .. Len);
+   end Encode;
+
+   --  Encode String in UTF-16
+
+   function Encode
+     (Item       : String;
+      Output_BOM : Boolean  := False) return UTF_16_Wide_String
+   is
+      Result : UTF_16_Wide_String
+                 (1 .. Item'Length + Boolean'Pos (Output_BOM));
+      --  Output is same length as input + possible BOM
+
+      Len : Integer;
+      --  Length of output string
+
+      C : Unsigned_8;
+
+   begin
+      --  Output BOM if required
+
+      if Output_BOM then
+         Result (1) := BOM_16 (1);
+         Len := 1;
+      else
+         Len := 0;
+      end if;
+
+      --  Loop through input characters encoding them
+
+      for Iptr in Item'Range loop
+         C := To_Unsigned_8 (Item (Iptr));
+
+         --  Codes in the range 16#0000#..16#00FF# are output unchanged. This
+         --  includes all possible cases of Character values.
+
+         Len := Len + 1;
+         Result (Len) := Wide_Character'Val (C);
+      end loop;
+
+      return Result;
+   end Encode;
+
+end Ada.Strings.UTF_Encoding.Strings;