2007-04-06 Thomas Quinot <quinot@adacore.com>

	    Pat Rogers  <rogers@adacore.com>
	    Pascal Obry  <obry@adacore.com>

	* g-stsifd-sockets.adb: New file.

	* g-socthi.ads, g-socket.adb, g-socthi-vxworks.adb,
	g-socthi-vxworks.ads, g-socthi-mingw.ads, g-socthi-vms.ads,
	g-socthi-vms.adb: Move signalling
	fd management to a nested package, so that they can conveniently be
	moved to a subunit that is shared across Windows, VMS, and VxWorks
	(Ada implementation) or completed with imported bodies from socket.c
	(UNIX case).
	(Read_Signalling_Fd, Write_Signalling_Fd, Create_Signalling_Fds): New
	subprograms.
	(Check_Selector): Use Read_Signalling_Fd to read and discard data from
	the signalling file descriptor.
	(Abort_Selector): Use Write_Signalling_Fd to write dummy data to the
	signalling file descriptor.
	(Create_Selector): Use new C-imported subprogram Create_Signalling_Fds
	instead of creating a pair of sockets for signalling here.

	* g-socthi.adb: Ditto.
	Set the runtime process to ignore SIGPIPEs on platforms that support
	neither SO_NOSIGPIPE nor MSG_NOSIGNAL functionality.

	* g-socthi-mingw.adb: Ditto.
	(WS_Version): Use Windows 2.2.
	Use Winsock 2.2 (instead of 1.1) for the GNAT.Socket API.

	* g-soliop-mingw.ads: Link with ws2_32 for Windows 2.x support.
	Use Winsock 2.2 (instead of 1.1) for the GNAT.Socket API.

	* Makefile.in: New libgnat pair g-stsifd.adb<g-stsifd-sockets.adb.
	added GNAT byte swapping facility
	Update FreeBSD THREADSLIB from -lc_r to -lpthread, for FreeBSD 6.

	* g-bytswa.adb, g-bytswa-x86.adb, g-bytswa.ads: New files.

	* socket.c (__gnat_read_signalling_fd, __gnat_write_controlling_fd):
	New subprograms.
	(__gnat_create_signalling_fds): New subprogram.
	Set the runtime process to ignore SIGPIPEs on platforms that support
	neither SO_NOSIGPIPE nor MSG_NOSIGNAL functionality.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@123542 138bc75d-0d04-0410-961f-82ee72b054a4

16 files changed, 1156 insertions, 248 deletions

diff --git a/gcc/ada/Makefile.in b/gcc/ada/Makefile.in
index 4e5c840b47b..ff27a4e070a 100644
--- a/gcc/ada/Makefile.in
+++ b/gcc/ada/Makefile.in
@@ -1,5 +1,5 @@
 # Makefile for GNU Ada Compiler (GNAT).
-#   Copyright (C) 1994-2005 Free Software Foundation, Inc.
+#   Copyright (C) 1994-2006 Free Software Foundation, Inc.
 
 #This file is part of GCC.
 
@@ -409,6 +409,7 @@ ifeq ($(strip $(filter-out m68k% wrs vx%,$(targ))),)
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
   g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   system.ads<system-vxworks-m68k.ads
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
@@ -444,7 +445,8 @@ ifeq ($(strip $(filter-out powerpc% wrs vxworks,$(targ))),)
   s-vxwork.ads<s-vxwork-ppc.ads \
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
-  g-socthi.adb<g-socthi-vxworks.adb
+  g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
 
@@ -501,6 +503,7 @@ ifeq ($(strip $(filter-out powerpc% wrs vxworksae,$(targ))),)
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
   g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   system.ads<system-vxworks-ppc-vthread.ads
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
@@ -546,6 +549,7 @@ ifeq ($(strip $(filter-out sparc% wrs vx%,$(targ))),)
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
   g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   system.ads<system-vxworks-sparcv9.ads   \
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
@@ -572,9 +576,11 @@ ifeq ($(strip $(filter-out %86 wrs vxworks,$(targ))),)
   s-taprop.adb<s-taprop-vxworks.adb \
   s-taspri.ads<s-taspri-vxworks.ads \
   s-vxwork.ads<s-vxwork-x86.ads \
+  g-bytswa.adb<g-bytswa-x86.adb \
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
-  g-socthi.adb<g-socthi-vxworks.adb
+  g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
 
@@ -627,6 +633,7 @@ ifeq ($(strip $(filter-out arm% coff wrs vx%,$(targ))),)
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
   g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   system.ads<system-vxworks-arm.ads
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
@@ -656,6 +663,7 @@ ifeq ($(strip $(filter-out mips% wrs vx%,$(targ))),)
   g-soccon.ads<g-soccon-vxworks.ads \
   g-socthi.ads<g-socthi-vxworks.ads \
   g-socthi.adb<g-socthi-vxworks.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   system.ads<system-vxworks-mips.ads
 
   TOOLS_TARGET_PAIRS=mlib-tgt.adb<mlib-tgt-vxworks.adb
@@ -752,6 +760,7 @@ ifeq ($(strip $(filter-out %86 solaris2%,$(arch) $(osys))),)
   s-tasinf.ads<s-tasinf-solaris.ads \
   s-taspri.ads<s-taspri-solaris.ads \
   s-tpopsp.adb<s-tpopsp-solaris.adb \
+  g-bytswa.adb<g-bytswa-x86.adb \
   g-soccon.ads<g-soccon-solaris.ads \
   g-soliop.ads<g-soliop-solaris.ads \
   system.ads<system-solaris-x86.ads
@@ -772,6 +781,7 @@ ifeq ($(strip $(filter-out %86 linux%,$(arch) $(osys))),)
   a-intnam.ads<a-intnam-linux.ads \
   a-numaux.adb<a-numaux-x86.adb \
   a-numaux.ads<a-numaux-x86.ads \
+  g-bytswa.adb<g-bytswa-x86.adb \
   g-soccon.ads<g-soccon-linux-x86.ads \
   s-inmaop.adb<s-inmaop-posix.adb \
   s-intman.adb<s-intman-posix.adb \
@@ -828,6 +838,7 @@ ifeq ($(strip $(filter-out %86 freebsd%,$(arch) $(osys))),)
   a-intnam.ads<a-intnam-freebsd.ads \
   a-numaux.adb<a-numaux-x86.adb \
   a-numaux.ads<a-numaux-x86.ads \
+  g-bytswa.adb<g-bytswa-x86.adb \
   g-soccon.ads<g-soccon-freebsd.ads \
   s-inmaop.adb<s-inmaop-posix.adb \
   s-intman.adb<s-intman-posix.adb \
@@ -844,7 +855,7 @@ ifeq ($(strip $(filter-out %86 freebsd%,$(arch) $(osys))),)
   GNATLIB_SHARED = gnatlib-shared-dual
 
   EH_MECHANISM=-gcc
-  THREADSLIB= -lc_r
+  THREADSLIB= -lpthread
   GMEM_LIB = gmemlib
   PREFIX_OBJS = $(PREFIX_REAL_OBJS)
   LIBRARY_VERSION := $(LIB_VERSION)
@@ -1010,6 +1021,7 @@ ifeq ($(strip $(filter-out lynxos,$(osys))),)
     a-numaux.adb<a-numaux-x86.adb \
     a-numaux.ads<a-numaux-x86.ads \
     a-intnam.ads<a-intnam-lynxos.ads \
+    g-bytswa.adb<g-bytswa-x86.adb \
     s-inmaop.adb<s-inmaop-posix.adb \
     s-intman.adb<s-intman-posix.adb \
     s-osinte.adb<s-osinte-lynxos.adb \
@@ -1142,6 +1154,7 @@ endif
   g-soccon.ads<g-soccon-vms.ads \
   g-socthi.ads<g-socthi-vms.ads \
   g-socthi.adb<g-socthi-vms.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   i-c.ads<i-c-vms_64.ads \
   i-cstrin.ads<i-cstrin-vms_64.ads \
   i-cstrin.adb<i-cstrin-vms_64.adb \
@@ -1212,8 +1225,10 @@ ifeq ($(strip $(filter-out cygwin32% mingw32% pe,$(osys))),)
   s-osprim.adb<s-osprim-mingw.adb \
   s-taprop.adb<s-taprop-mingw.adb \
   s-taspri.ads<s-taspri-mingw.ads \
+  g-bytswa.adb<g-bytswa-x86.adb \
   g-socthi.ads<g-socthi-mingw.ads \
   g-socthi.adb<g-socthi-mingw.adb \
+  g-stsifd.adb<g-stsifd-sockets.adb \
   g-soccon.ads<g-soccon-mingw.ads \
   g-soliop.ads<g-soliop-mingw.ads \
   system.ads<system-mingw.ads
diff --git a/gcc/ada/g-bytswa-x86.adb b/gcc/ada/g-bytswa-x86.adb
new file mode 100644
index 00000000000..1ec8a0f1be7
--- /dev/null
+++ b/gcc/ada/g-bytswa-x86.adb
@@ -0,0 +1,194 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--                    G N A T . B Y T E _ S W A P P I N G                   --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--                      Copyright (C) 2006, AdaCore                         --
+--                                                                          --
+-- 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 2,  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.  See the GNU General Public License --
+-- for  more details.  You should have  received  a copy of the GNU General --
+-- Public License  distributed with GNAT;  see file COPYING.  If not, write --
+-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
+-- Boston, MA 02110-1301, USA.                                              --
+--                                                                          --
+-- As a special exception,  if other files  instantiate  generics from this --
+-- unit, or you link  this unit with other files  to produce an executable, --
+-- this  unit  does not  by itself cause  the resulting  executable  to  be --
+-- covered  by the  GNU  General  Public  License.  This exception does not --
+-- however invalidate  any other reasons why  the executable file  might be --
+-- covered by the  GNU Public License.                                      --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This is a machine-specific version of this package.
+--  It uses instructions available on Intel 486 processors (or later).
+
+with Interfaces;          use Interfaces;
+with System.Machine_Code; use System.Machine_Code;
+with Ada.Unchecked_Conversion;
+
+package body GNAT.Byte_Swapping is
+
+   -----------------------
+   -- Local Subprograms --
+   -----------------------
+
+   function Swapped32 (Value : Unsigned_32) return Unsigned_32;
+   pragma Inline_Always (Swapped32);
+
+   --------------
+   -- Swapped2 --
+   --------------
+
+   function Swapped2 (Input : Item) return Item is
+
+      function As_U16 is new Ada.Unchecked_Conversion
+         (Source => Item, Target => Unsigned_16);
+
+      function As_Item is new Ada.Unchecked_Conversion
+         (Source => Unsigned_16, Target => Item);
+
+      X : Unsigned_16 := As_U16 (Input);
+
+   begin
+      Asm ("xchgb %b0,%h0",
+           Unsigned_16'Asm_Output ("=q", X),
+           Unsigned_16'Asm_Input ("0", X));
+      return As_Item (X);
+   end Swapped2;
+
+   --------------
+   -- Swapped4 --
+   --------------
+
+   function Swapped4 (Input : Item) return Item is
+
+      function As_U32 is new Ada.Unchecked_Conversion
+         (Source => Item, Target => Unsigned_32);
+
+      function As_Item is new Ada.Unchecked_Conversion
+         (Source => Unsigned_32, Target => Item);
+
+      X : Unsigned_32 := As_U32 (Input);
+
+   begin
+      Asm ("bswap %0",
+           Unsigned_32'Asm_Output ("=r", X),
+           Unsigned_32'Asm_Input ("0", X));
+      return As_Item (X);
+   end Swapped4;
+
+   --------------
+   -- Swapped8 --
+   --------------
+
+   function Swapped8 (Input : Item) return Item is
+
+      function As_U64 is new Ada.Unchecked_Conversion
+         (Source => Item, Target => Unsigned_64);
+
+      X : Unsigned_64 renames As_U64 (Input);
+
+      type Two_Words is array (0 .. 1) of Unsigned_32;
+      for Two_Words'Component_Size use Unsigned_32'Size;
+
+      function As_Item is new Ada.Unchecked_Conversion
+        (Source => Two_Words, Target => Item);
+
+      Result : Two_Words;
+
+   begin
+      Asm ("xchgl %0,%1",
+         Outputs =>
+            (Unsigned_32'Asm_Output ("=r", Result (0)),
+             Unsigned_32'Asm_Output ("=r", Result (1))),
+         Inputs =>
+            (Unsigned_32'Asm_Input ("0",
+                Swapped32 (Unsigned_32 (X and 16#0000_0000_FFFF_FFFF#))),
+             Unsigned_32'Asm_Input ("1",
+                Swapped32 (Unsigned_32 (Shift_Right (X, 32))))));
+      return As_Item (Result);
+   end Swapped8;
+
+   -----------
+   -- Swap2 --
+   -----------
+
+   procedure Swap2 (Location : in System.Address) is
+
+      X : Unsigned_16;
+      for X'Address use Location;
+
+   begin
+      Asm ("xchgb %b0,%h0",
+           Unsigned_16'Asm_Output ("=q", X),
+           Unsigned_16'Asm_Input ("0", X));
+   end Swap2;
+
+   -----------
+   -- Swap4 --
+   -----------
+
+   procedure Swap4 (Location : in System.Address) is
+
+      X : Unsigned_32;
+      for X'Address use Location;
+
+   begin
+      Asm ("bswap %0",
+           Unsigned_32'Asm_Output ("=r", X),
+           Unsigned_32'Asm_Input ("0", X));
+   end Swap4;
+
+   ---------------
+   -- Swapped32 --
+   ---------------
+
+   function Swapped32 (Value : Unsigned_32) return Unsigned_32 is
+      X : Unsigned_32 := Value;
+   begin
+      Asm ("bswap %0",
+           Unsigned_32'Asm_Output ("=r", X),
+           Unsigned_32'Asm_Input ("0", X));
+      return X;
+   end Swapped32;
+
+   -----------
+   -- Swap8 --
+   -----------
+
+   procedure Swap8 (Location : in System.Address) is
+
+      X : Unsigned_64;
+      for X'Address use Location;
+
+      type Two_Words is array (0 .. 1) of Unsigned_32;
+      for Two_Words'Component_Size use Unsigned_32'Size;
+
+      Words : Two_Words;
+      for Words'Address use Location;
+
+   begin
+      Asm ("xchgl %0,%1",
+         Outputs =>
+            (Unsigned_32'Asm_Output ("=r", Words (0)),
+             Unsigned_32'Asm_Output ("=r", Words (1))),
+         Inputs =>
+            (Unsigned_32'Asm_Input ("0",
+                Swapped32 (Unsigned_32 (X and 16#0000_0000_FFFF_FFFF#))),
+             Unsigned_32'Asm_Input ("1",
+                Swapped32 (Unsigned_32 (Shift_Right (X, 32))))));
+   end Swap8;
+
+end GNAT.Byte_Swapping;
diff --git a/gcc/ada/g-bytswa.adb b/gcc/ada/g-bytswa.adb
new file mode 100644
index 00000000000..254e638bed5
--- /dev/null
+++ b/gcc/ada/g-bytswa.adb
@@ -0,0 +1,156 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--                    G N A T . B Y T E _ S W A P P I N G                   --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--                      Copyright (C) 2006, AdaCore                         --
+--                                                                          --
+-- 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 2,  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.  See the GNU General Public License --
+-- for  more details.  You should have  received  a copy of the GNU General --
+-- Public License  distributed with GNAT;  see file COPYING.  If not, write --
+-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
+-- Boston, MA 02110-1301, USA.                                              --
+--                                                                          --
+-- As a special exception,  if other files  instantiate  generics from this --
+-- unit, or you link  this unit with other files  to produce an executable, --
+-- this  unit  does not  by itself cause  the resulting  executable  to  be --
+-- covered  by the  GNU  General  Public  License.  This exception does not --
+-- however invalidate  any other reasons why  the executable file  might be --
+-- covered by the  GNU Public License.                                      --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  This is a general implementation that does not take advantage of
+--  any machine-specific instructions.
+
+with Interfaces; use Interfaces;
+with Ada.Unchecked_Conversion;
+
+package body GNAT.Byte_Swapping is
+
+   --------------
+   -- Swapped2 --
+   --------------
+
+   function Swapped2 (Input : Item) return Item is
+
+      function As_U16 is new Ada.Unchecked_Conversion
+         (Source => Item, Target => Unsigned_16);
+
+      function As_Item is new Ada.Unchecked_Conversion
+         (Source => Unsigned_16, Target => Item);
+
+      X : Unsigned_16 renames As_U16 (Input);
+
+   begin
+      return As_Item ((Shift_Left (X, 8)  and 16#FF00#) or
+                      (Shift_Right (X, 8) and 16#00FF#));
+   end Swapped2;
+
+   --------------
+   -- Swapped4 --
+   --------------
+
+   function Swapped4 (Input : Item) return Item is
+
+      function As_U32 is new Ada.Unchecked_Conversion
+         (Source => Item, Target => Unsigned_32);
+
+      function As_Item is new Ada.Unchecked_Conversion
+         (Source => Unsigned_32, Target => Item);
+
+      X : Unsigned_32 renames As_U32 (Input);
+
+   begin
+      return As_Item ((Shift_Right (X, 24) and 16#0000_00FF#) or
+                      (Shift_Right (X, 8)  and 16#0000_FF00#) or
+                      (Shift_Left (X, 8)   and 16#00FF_0000#) or
+                      (Shift_Left (X, 24)  and 16#FF00_0000#));
+   end Swapped4;
+
+   --------------
+   -- Swapped8 --
+   --------------
+
+   function Swapped8 (Input : Item) return Item is
+
+      function As_U64 is new Ada.Unchecked_Conversion
+         (Source => Item, Target => Unsigned_64);
+
+      function As_Item is new Ada.Unchecked_Conversion
+         (Source => Unsigned_64, Target => Item);
+
+      X : Unsigned_64 renames As_U64 (Input);
+
+      Low, High : aliased Unsigned_32;
+
+   begin
+      Low := Unsigned_32 (X and 16#0000_0000_FFFF_FFFF#);
+      Swap4 (Low'Address);
+      High := Unsigned_32 (Shift_Right (X, 32));
+      Swap4 (High'Address);
+      return As_Item
+         (Shift_Left (Unsigned_64 (Low), 32) or Unsigned_64 (High));
+   end Swapped8;
+
+   -----------
+   -- Swap2 --
+   -----------
+
+   procedure Swap2 (Location : System.Address) is
+
+      X : Unsigned_16;
+      for X'Address use Location;
+
+   begin
+      X := (Shift_Left (X, 8)  and 16#FF00#) or
+           (Shift_Right (X, 8) and 16#00FF#);
+   end Swap2;
+
+   -----------
+   -- Swap4 --
+   -----------
+
+   procedure Swap4 (Location : System.Address) is
+
+      X : Unsigned_32;
+      for X'Address use Location;
+
+   begin
+      X := (Shift_Right (X, 24) and 16#0000_00FF#) or
+           (Shift_Right (X, 8)  and 16#0000_FF00#) or
+           (Shift_Left (X, 8)   and 16#00FF_0000#) or
+           (Shift_Left (X, 24)  and 16#FF00_0000#);
+   end Swap4;
+
+   -----------
+   -- Swap8 --
+   -----------
+
+   procedure Swap8 (Location : System.Address) is
+
+      X : Unsigned_64;
+      for X'Address use Location;
+
+      Low, High : aliased Unsigned_32;
+
+   begin
+      Low := Unsigned_32 (X and 16#0000_0000_FFFF_FFFF#);
+      Swap4 (Low'Address);
+      High := Unsigned_32 (Shift_Right (X, 32));
+      Swap4 (High'Address);
+      X := Shift_Left (Unsigned_64 (Low), 32) or Unsigned_64 (High);
+   end Swap8;
+
+end GNAT.Byte_Swapping;
diff --git a/gcc/ada/g-bytswa.ads b/gcc/ada/g-bytswa.ads
new file mode 100644
index 00000000000..5c9741482ea
--- /dev/null
+++ b/gcc/ada/g-bytswa.ads
@@ -0,0 +1,206 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT RUN-TIME COMPONENTS                         --
+--                                                                          --
+--                    G N A T . B Y T E _ S W A P P I N G                   --
+--                                                                          --
+--                                 S p e c                                  --
+--                                                                          --
+--                      Copyright (C) 2006, AdaCore                         --
+--                                                                          --
+-- 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 2,  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.  See the GNU General Public License --
+-- for  more details.  You should have  received  a copy of the GNU General --
+-- Public License  distributed with GNAT;  see file COPYING.  If not, write --
+-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
+-- Boston, MA 02110-1301, USA.                                              --
+--                                                                          --
+-- As a special exception,  if other files  instantiate  generics from this --
+-- unit, or you link  this unit with other files  to produce an executable, --
+-- this  unit  does not  by itself cause  the resulting  executable  to  be --
+-- covered  by the  GNU  General  Public  License.  This exception does not --
+-- however invalidate  any other reasons why  the executable file  might be --
+-- covered by the  GNU Public License.                                      --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  Simple routines for swapping the bytes of 16-, 32-, and 64-bit objects.
+
+--  The generic functions should be instantiated with types that
+--  are of a size in bytes corresponding to the name of the generic. For
+--  example, a 2-byte integer type would be compatible with Swapped2, 4-byte
+--  integer with Swapped4, and so on. Failure to do so will result in a
+--  warning when compiling the instantiation; this warning should be heeded.
+--  Ignoring this warning can result in unexpected results.
+
+--  An example of proper usage follows:
+
+--     declare
+--        type Short_Integer is range -32768 .. 32767;
+--        for Short_Integer'Size use 16; -- for confirmation
+
+--        X : Short_Integer := 16#7FFF#;
+
+--        function Swapped is new Byte_Swapping.Swapped2 (Short_Integer);
+
+--     begin
+--        Put_Line (X'Img);
+--        X := Swapped (X);
+--        Put_Line (X'Img);
+--     end;
+
+--  Note that the generic actual types need not be scalars, but must be
+--  'definite' types. They can, for example, be constrained subtypes of
+--  unconstrained array types as long as the size is correct. For instance,
+--  a subtype of String with length of 4 would be compatible with the
+--  Swapped4 generic:
+
+--     declare
+--        subtype String4 is String (1 .. 4);
+--        function Swapped is new Byte_Swapping.Swapped4 (String4);
+--        S : String4 := "ABCD";
+--     begin
+--        Put_Line (S);
+--        S := Swapped (S);
+--        Put_Line (S);
+--     end;
+
+--  Similarly, a constrained array type is also acceptable:
+
+--     declare
+--        type Mask is array (0 .. 15) of Boolean;
+--        for Mask'Component_Size use Boolean'Size;
+--        X : Mask := (0 .. 7 => True, others => False);
+--        function Swapped is new Byte_Swapping.Swapped2 (Mask);
+--     begin
+--        ...
+--        X := Swapped (X);
+--        ...
+--     end;
+
+--  A properly-sized record type will also be acceptable, and so forth.
+
+--  However, as described, a size mismatch must be avoided. In the following
+--  we instantiate one of the generics with a type that is too large. The
+--  result of the function call is undefined, such that assignment to an
+--  object can result in garbage values.
+
+--     Wrong: declare
+--        subtype String16 is String (1 .. 16);
+
+--        function Swapped is new Byte_Swapping.Swapped8 (String16);
+--        --  Instantiation generates a compiler warning about
+--        --  mismatched sizes
+
+--        S : String16;
+
+--     begin
+--        S := "ABCDEFGHDEADBEEF";
+--
+--        Put_Line (S);
+--
+--        --  the following assignment results in garbage in S after the
+--        --  first 8 bytes
+--
+--        S := Swapped (S);
+--
+--        Put_Line (S);
+--     end Wrong;
+
+--  When the size of the type is larger than 8 bytes, the use of the
+--  non-generic procedures is an alternative because no function result is
+--  involved; manipulation of the object is direct.
+
+--  The procedures are passed the address of an object to manipulate. They will
+--  swap the first N bytes of that object corresponding to the name of the
+--  procedure.  For example:
+
+--     declare
+--        S2 : String := "AB";
+--        for S2'Alignment use 2;
+--        S4 : String := "ABCD";
+--        for S4'Alignment use 4;
+--        S8 : String := "ABCDEFGH";
+--        for S8'Alignment use 8;
+
+--     begin
+--        Swap2 (S2'Address);
+--        Put_Line (S2);
+
+--        Swap4 (S4'Address);
+--        Put_Line (S4);
+
+--        Swap8 (S8'Address);
+--        Put_Line (S8);
+--     end;
+
+--  If an object of a type larger than N is passed, the remaining
+--  bytes of the object are undisturbed.  For example:
+
+--     declare
+--        subtype String16 is String (1 .. 16);
+
+--        S : String16;
+--        for S'Alignment use 8;
+
+--     begin
+--        S  := "ABCDEFGHDEADBEEF";
+--        Put_Line (S);
+--        Swap8 (S'Address);
+--        Put_Line (S);
+--     end;
+
+with System;
+
+package GNAT.Byte_Swapping is
+   pragma Pure;
+
+   --  NB: all the routines in this package treat the application objects as
+   --  unsigned (modular) types of a size in bytes corresponding to the routine
+   --  name. For example, the generic function Swapped2 manipulates the object
+   --  passed to the formal parameter Input as a value of an unsigned type that
+   --  is 2 bytes long. Therefore clients are responsible for the compatibility
+   --  of application types manipulated by these routines and these modular
+   --  types, in terms of both size and alignment. This requirement applies to
+   --  the generic actual type passed to the generic formal type Item in the
+   --  generic functions, as well as to the type of the object implicitly
+   --  designated by the address passed to the non-generic procedures. Use of
+   --  incompatible types can result in implementation- defined effects.
+
+   generic
+      type Item is limited private;
+   function Swapped2 (Input : Item) return Item;
+   --  Return the 2-byte value of Input with the bytes swapped
+
+   generic
+      type Item is limited private;
+   function Swapped4 (Input : Item) return Item;
+   --  Return the 4-byte value of Input with the bytes swapped
+
+   generic
+      type Item is limited private;
+   function Swapped8 (Input : Item) return Item;
+   --  Return the 8-byte value of Input with the bytes swapped
+
+   procedure Swap2 (Location : System.Address);
+   --  Swap the first 2 bytes of the object starting at the address specified
+   --  by Location.
+
+   procedure Swap4 (Location : System.Address);
+   --  Swap the first 4 bytes of the object starting at the address specified
+   --  by Location.
+
+   procedure Swap8 (Location : System.Address);
+   --  Swap the first 8 bytes of the object starting at the address specified
+   --  by Location.
+
+   pragma Inline (Swap2, Swap4, Swap8, Swapped2, Swapped4, Swapped8);
+
+end GNAT.Byte_Swapping;
diff --git a/gcc/ada/g-socket.adb b/gcc/ada/g-socket.adb
index 01765a70715..2773b7ab036 100644
--- a/gcc/ada/g-socket.adb
+++ b/gcc/ada/g-socket.adb
@@ -236,14 +236,13 @@ package body GNAT.Sockets is
    --------------------
 
    procedure Abort_Selector (Selector : Selector_Type) is
-      Buf : aliased Character := ASCII.NUL;
       Res : C.int;
 
    begin
-      --  Send an empty array to unblock C select system call
+      --  Send one byte to unblock select system call
+
+      Res := Signalling_Fds.Write (C.int (Selector.W_Sig_Socket));
 
-      Res := C_Send (C.int (Selector.W_Sig_Socket), Buf'Address, 1,
-                     Constants.MSG_Forced_Flags);
       if Res = Failure then
          Raise_Socket_Error (Socket_Errno);
       end if;
@@ -454,16 +453,11 @@ package body GNAT.Sockets is
          if Is_Set (RSet, RSig) then
             Clear (RSet, RSig);
 
-            declare
-               Buf : Character;
-
-            begin
-               Res := C_Recv (C.int (RSig), Buf'Address, 1, 0);
+            Res := Signalling_Fds.Read (C.int (RSig));
 
-               if Res = Failure then
-                  Raise_Socket_Error (Socket_Errno);
-               end if;
-            end;
+            if Res = Failure then
+               Raise_Socket_Error (Socket_Errno);
+            end if;
 
             Status := Aborted;
 
@@ -674,105 +668,23 @@ package body GNAT.Sockets is
    ---------------------
 
    procedure Create_Selector (Selector : out Selector_Type) is
-      S0  : C.int;
-      S1  : C.int;
-      S2  : C.int;
-      Res : C.int;
-      Sin : aliased Sockaddr_In;
-      Len : aliased C.int := Sin'Size / 8;
-      Err : Integer;
+      Two_Fds : aliased Fd_Pair;
+      Res     : C.int;
 
    begin
-      --  We open two signalling sockets. One of them is used to send data to
-      --  the other, which is included in a C_Select socket set. The
-      --  communication is used to force the call to C_Select to complete, and
+      --  We open two signalling file descriptors. One of them is used to send
+      --  data to the other, which is included in a C_Select socket set. The
+      --  communication is used to force a call to C_Select to complete, and
       --  the waiting task to resume its execution.
 
-      --  Create a listening socket
-
-      S0 := C_Socket (Constants.AF_INET, Constants.SOCK_STREAM, 0);
-
-      if S0 = Failure then
-         Raise_Socket_Error (Socket_Errno);
-      end if;
-
-      --  Bind the socket to any unused port on localhost
-
-      Sin.Sin_Addr.S_B1 := 127;
-      Sin.Sin_Addr.S_B2 := 0;
-      Sin.Sin_Addr.S_B3 := 0;
-      Sin.Sin_Addr.S_B4 := 1;
-      Sin.Sin_Port := 0;
-
-      Res := C_Bind (S0, Sin'Address, Len);
-
-      if Res = Failure then
-         Err := Socket_Errno;
-         Res := C_Close (S0);
-         Raise_Socket_Error (Err);
-      end if;
-
-      --  Get the port used by the socket
-
-      Res := C_Getsockname (S0, Sin'Address, Len'Access);
-
-      if Res = Failure then
-         Err := Socket_Errno;
-         Res := C_Close (S0);
-         Raise_Socket_Error (Err);
-      end if;
-
-      --  Set backlog to 1 to guarantee that exactly one call to connect(2)
-      --  can succeed.
-
-      Res := C_Listen (S0, 1);
-
-      if Res = Failure then
-         Err := Socket_Errno;
-         Res := C_Close (S0);
-         Raise_Socket_Error (Err);
-      end if;
-
-      S1 := C_Socket (Constants.AF_INET, Constants.SOCK_STREAM, 0);
-
-      if S1 = Failure then
-         Err := Socket_Errno;
-         Res := C_Close (S0);
-         Raise_Socket_Error (Err);
-      end if;
-
-      --  Do a connect and accept the connection
-
-      Res := C_Connect (S1, Sin'Address, Len);
-
-      if Res = Failure then
-         Err := Socket_Errno;
-         Res := C_Close (S0);
-         Res := C_Close (S1);
-         Raise_Socket_Error (Err);
-      end if;
-
-      --  Since the call to connect(2) has suceeded and the backlog limit on
-      --  the listening socket is 1, we know that there is now exactly one
-      --  pending connection on S0, which is the one from S1.
-
-      S2 := C_Accept (S0, Sin'Address, Len'Access);
-
-      if S2 = Failure then
-         Err := Socket_Errno;
-         Res := C_Close (S0);
-         Res := C_Close (S1);
-         Raise_Socket_Error (Err);
-      end if;
-
-      Res := C_Close (S0);
+      Res := Signalling_Fds.Create (Two_Fds'Access);
 
       if Res = Failure then
          Raise_Socket_Error (Socket_Errno);
       end if;
 
-      Selector.R_Sig_Socket := Socket_Type (S1);
-      Selector.W_Sig_Socket := Socket_Type (S2);
+      Selector.R_Sig_Socket := Socket_Type (Two_Fds (Read_End));
+      Selector.W_Sig_Socket := Socket_Type (Two_Fds (Write_End));
    end Create_Selector;
 
    -------------------
@@ -1073,7 +985,7 @@ package body GNAT.Sockets is
    is
       use type C.unsigned_char;
 
-      V8  : aliased Two_Int;
+      V8  : aliased Two_Ints;
       V4  : aliased C.int;
       V1  : aliased C.unsigned_char;
       VT  : aliased Timeval;
@@ -1899,7 +1811,7 @@ package body GNAT.Sockets is
       Level  : Level_Type := Socket_Level;
       Option : Option_Type)
    is
-      V8  : aliased Two_Int;
+      V8  : aliased Two_Ints;
       V4  : aliased C.int;
       V1  : aliased C.unsigned_char;
       VT  : aliased Timeval;
diff --git a/gcc/ada/g-socthi-mingw.adb b/gcc/ada/g-socthi-mingw.adb
index 862305dbd2e..1b74d907670 100644
--- a/gcc/ada/g-socthi-mingw.adb
+++ b/gcc/ada/g-socthi-mingw.adb
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---                     Copyright (C) 2001-2005, AdaCore                     --
+--                     Copyright (C) 2001-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -48,13 +48,13 @@ package body GNAT.Sockets.Thin is
 
    WSAData_Dummy : array (1 .. 512) of C.int;
 
-   WS_Version  : constant := 16#0101#;
+   WS_Version  : constant := 16#0202#;
    Initialized : Boolean := False;
 
-   SYSNOTREADY          : constant := 10091;
-   VERNOTSUPPORTED      : constant := 10092;
-   NOTINITIALISED       : constant := 10093;
-   EDISCON              : constant := 10101;
+   SYSNOTREADY     : constant := 10091;
+   VERNOTSUPPORTED : constant := 10092;
+   NOTINITIALISED  : constant := 10093;
+   EDISCON         : constant := 10101;
 
    function Standard_Connect
      (S       : C.int;
@@ -258,11 +258,11 @@ package body GNAT.Sockets.Thin is
    -------------
 
    function C_Readv
-     (Socket : C.int;
+     (Fd     : C.int;
       Iov    : System.Address;
       Iovcnt : C.int) return C.int
    is
-      Res : C.int;
+      Res   : C.int;
       Count : C.int := 0;
 
       Iovec : array (0 .. Iovcnt - 1) of Vector_Element;
@@ -272,7 +272,7 @@ package body GNAT.Sockets.Thin is
    begin
       for J in Iovec'Range loop
          Res := C_Recv
-           (Socket,
+           (Fd,
             Iovec (J).Base.all'Address,
             C.int (Iovec (J).Length),
             0);
@@ -434,11 +434,11 @@ package body GNAT.Sockets.Thin is
    --------------
 
    function C_Writev
-     (Socket : C.int;
+     (Fd     : C.int;
       Iov    : System.Address;
       Iovcnt : C.int) return C.int
    is
-      Res : C.int;
+      Res   : C.int;
       Count : C.int := 0;
 
       Iovec : array (0 .. Iovcnt - 1) of Vector_Element;
@@ -448,7 +448,7 @@ package body GNAT.Sockets.Thin is
    begin
       for J in Iovec'Range loop
          Res := C_Send
-           (Socket,
+           (Fd,
             Iovec (J).Base.all'Address,
             C.int (Iovec (J).Length),
             0);
@@ -478,7 +478,7 @@ package body GNAT.Sockets.Thin is
    -- Initialize --
    ----------------
 
-   procedure Initialize (Process_Blocking_IO : Boolean := False) is
+   procedure Initialize (Process_Blocking_IO : Boolean) is
       pragma Unreferenced (Process_Blocking_IO);
 
       Return_Value : Interfaces.C.int;
@@ -542,6 +542,12 @@ package body GNAT.Sockets.Thin is
       Sin.Sin_Port := Port;
    end Set_Port;
 
+   --------------------
+   -- Signalling_Fds --
+   --------------------
+
+   package body Signalling_Fds is separate;
+
    --------------------------
    -- Socket_Error_Message --
    --------------------------
diff --git a/gcc/ada/g-socthi-mingw.ads b/gcc/ada/g-socthi-mingw.ads
index 11509c095ea..9db2866f5cf 100644
--- a/gcc/ada/g-socthi-mingw.ads
+++ b/gcc/ada/g-socthi-mingw.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---                     Copyright (C) 2001-2005, AdaCore                     --
+--                     Copyright (C) 2001-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -60,10 +60,9 @@ package GNAT.Sockets.Thin is
    procedure Set_Socket_Errno (Errno : Integer);
    --  Set last socket error number
 
-   function Socket_Error_Message
-     (Errno : Integer) return C.Strings.chars_ptr;
-   --  Returns the error message string for the error number Errno. If
-   --  Errno is not known it returns "Unknown system error".
+   function Socket_Error_Message (Errno : Integer) return C.Strings.chars_ptr;
+   --  Returns the error message string for the error number Errno. If Errno is
+   --  not known it returns "Unknown system error".
 
    function Host_Errno return Integer;
    pragma Import (C, Host_Errno, "__gnat_get_h_errno");
@@ -73,14 +72,14 @@ package GNAT.Sockets.Thin is
    No_Fd_Set : constant Fd_Set_Access := System.Null_Address;
 
    type time_t is
-     range -(2 ** (8 * Constants.SIZEOF_tv_sec - 1))
-          .. 2 ** (8 * Constants.SIZEOF_tv_sec - 1) - 1;
+     range -2 ** (8 * Constants.SIZEOF_tv_sec - 1)
+         .. 2 ** (8 * Constants.SIZEOF_tv_sec - 1) - 1;
    for time_t'Size use 8 * Constants.SIZEOF_tv_sec;
    pragma Convention (C, time_t);
 
    type suseconds_t is
-     range -(2 ** (8 * Constants.SIZEOF_tv_usec - 1))
-          .. 2 ** (8 * Constants.SIZEOF_tv_usec - 1) - 1;
+     range -2 ** (8 * Constants.SIZEOF_tv_usec - 1)
+         .. 2 ** (8 * Constants.SIZEOF_tv_usec - 1) - 1;
    for suseconds_t'Size use 8 * Constants.SIZEOF_tv_usec;
    pragma Convention (C, suseconds_t);
 
@@ -104,7 +103,7 @@ package GNAT.Sockets.Thin is
 
    package Chars_Ptr_Pointers is
       new C.Pointers (C.size_t, C.Strings.chars_ptr, Chars_Ptr_Array,
-                    C.Strings.Null_Ptr);
+                      C.Strings.Null_Ptr);
    --  Arrays of C (char *)
 
    type In_Addr is record
@@ -123,6 +122,7 @@ package GNAT.Sockets.Thin is
    type In_Addr_Access_Array is array (C.size_t range <>)
      of aliased In_Addr_Access;
    pragma Convention (C, In_Addr_Access_Array);
+
    package In_Addr_Access_Pointers is
      new C.Pointers (C.size_t, In_Addr_Access, In_Addr_Access_Array, null);
    --  Array of internet addresses
@@ -203,14 +203,24 @@ package GNAT.Sockets.Thin is
    pragma Convention (C, Servent_Access);
    --  Access to service entry
 
-   type Two_Int is array (0 .. 1) of C.int;
-   pragma Convention (C, Two_Int);
-   --  Used with pipe()
+   type Two_Ints is array (0 .. 1) of C.int;
+   pragma Convention (C, Two_Ints);
+   --  Container for two int values
+
+   subtype Fd_Pair is Two_Ints;
+   --  Two_Ints as used for Create_Signalling_Fds: a pair of connected file
+   --  descriptors, one of which (the "read end" of the connection) being used
+   --  for reading, the other one (the "write end") being used for writing.
+
+   Read_End  : constant := 0;
+   Write_End : constant := 1;
+   --  Indices into an Fd_Pair value providing access to each of the connected
+   --  file descriptors.
 
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
 
    function C_Bind
      (S       : C.int;
@@ -226,9 +236,9 @@ package GNAT.Sockets.Thin is
       Namelen : C.int) return C.int;
 
    function C_Gethostbyaddr
-     (Addr     : System.Address;
-      Length   : C.int;
-      Typ      : C.int) return Hostent_Access;
+     (Addr : System.Address;
+      Len  : C.int;
+      Typ  : C.int) return Hostent_Access;
 
    function C_Gethostbyname
      (Name : C.char_array) return Hostent_Access;
@@ -240,7 +250,7 @@ package GNAT.Sockets.Thin is
    function C_Getpeername
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getservbyname
      (Name  : C.char_array;
@@ -253,14 +263,14 @@ package GNAT.Sockets.Thin is
    function C_Getsockname
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getsockopt
      (S       : C.int;
       Level   : C.int;
       Optname : C.int;
       Optval  : System.Address;
-      Optlen  : access C.int) return C.int;
+      Optlen  : not null access C.int) return C.int;
 
    function C_Inet_Addr
      (Cp : C.Strings.chars_ptr) return C.int;
@@ -275,23 +285,23 @@ package GNAT.Sockets.Thin is
       Backlog : C.int) return C.int;
 
    function C_Readv
-     (Socket : C.int;
+     (Fd     : C.int;
       Iov    : System.Address;
       Iovcnt : C.int) return C.int;
 
    function C_Recv
      (S     : C.int;
-      Buf   : System.Address;
+      Msg   : System.Address;
       Len   : C.int;
       Flags : C.int) return C.int;
 
    function C_Recvfrom
      (S       : C.int;
-      Buf     : System.Address;
+      Msg     : System.Address;
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
 
    function C_Select
      (Nfds      : C.int;
@@ -302,7 +312,7 @@ package GNAT.Sockets.Thin is
 
    function C_Send
      (S     : C.int;
-      Buf   : System.Address;
+      Msg   : System.Address;
       Len   : C.int;
       Flags : C.int) return C.int;
 
@@ -322,8 +332,8 @@ package GNAT.Sockets.Thin is
       Optlen  : C.int) return C.int;
 
    function C_Shutdown
-     (S    : C.int;
-      How  : C.int) return C.int;
+     (S   : C.int;
+      How : C.int) return C.int;
 
    function C_Socket
      (Domain   : C.int;
@@ -337,7 +347,7 @@ package GNAT.Sockets.Thin is
      (Command : System.Address) return C.int;
 
    function C_Writev
-     (Socket : C.int;
+     (Fd     : C.int;
       Iov    : System.Address;
       Iovcnt : C.int) return C.int;
 
@@ -345,6 +355,25 @@ package GNAT.Sockets.Thin is
      (WS_Version     : Interfaces.C.int;
       WSADataAddress : System.Address) return Interfaces.C.int;
 
+   package Signalling_Fds is
+
+      function Create (Fds : not null access Fd_Pair) return C.int;
+      pragma Convention (C, Create);
+      --  Create a pair of connected descriptors suitable for use with C_Select
+      --  (used for signalling in Selector objects).
+
+      function Read (Rsig : C.int) return C.int;
+      pragma Convention (C, Read);
+      --  Read one byte of data from rsig, the read end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+      function Write (Wsig : C.int) return C.int;
+      pragma Convention (C, Write);
+      --  Write one byte of data to wsig, the write end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+   end Signalling_Fds;
+
    procedure Free_Socket_Set
      (Set : Fd_Set_Access);
    --  Free system-dependent socket set
@@ -371,19 +400,19 @@ package GNAT.Sockets.Thin is
    --  value if it is, zero if it is not.
 
    procedure Last_Socket_In_Set
-     (Set  : Fd_Set_Access;
-      Last : Int_Access);
-   --  Find the largest socket in the socket set. This is needed for
-   --  select(). When Last_Socket_In_Set is called, parameter Last is
-   --  a maximum value of the largest socket. This hint is used to
-   --  avoid scanning very large socket sets. After the call, Last is
-   --  set back to the real largest socket in the socket set.
+     (Set    : Fd_Set_Access;
+      Last   : Int_Access);
+   --  Find the largest socket in the socket set. This is needed for select().
+   --  When Last_Socket_In_Set is called, parameter Last is a maximum value of
+   --  the largest socket. This hint is used to avoid scanning very large
+   --  socket sets. After the call, Last is set back to the real largest socket
+   --  in the socket set.
 
    function  New_Socket_Set
      (Set : Fd_Set_Access) return Fd_Set_Access;
-   --  Allocate a new socket set which is a system-dependent structure
-   --  and initialize by copying Set if it is non-null, by making it
-   --  empty otherwise.
+   --  Allocate a new socket set which is a system-dependent structure and
+   --  initialize by copying Set if it is non-null, by making it empty
+   --  otherwise.
 
    procedure Remove_Socket_From_Set
      (Set    : Fd_Set_Access;
@@ -393,7 +422,7 @@ package GNAT.Sockets.Thin is
    procedure WSACleanup;
 
    procedure Finalize;
-   procedure Initialize (Process_Blocking_IO : Boolean := False);
+   procedure Initialize (Process_Blocking_IO : Boolean);
 
 private
    pragma Import (Stdcall, C_Accept, "accept");
@@ -430,4 +459,5 @@ private
    pragma Import (C, New_Socket_Set, "__gnat_new_socket_set");
    pragma Import (C, Insert_Socket_In_Set, "__gnat_insert_socket_in_set");
    pragma Import (C, Remove_Socket_From_Set, "__gnat_remove_socket_from_set");
+
 end GNAT.Sockets.Thin;
diff --git a/gcc/ada/g-socthi-vms.adb b/gcc/ada/g-socthi-vms.adb
index d1545e050fe..0ede7e7973d 100644
--- a/gcc/ada/g-socthi-vms.adb
+++ b/gcc/ada/g-socthi-vms.adb
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---                     Copyright (C) 2001-2005, AdaCore                     --
+--                     Copyright (C) 2001-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -64,7 +64,7 @@ package body GNAT.Sockets.Thin is
    function Syscall_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
    pragma Import (C, Syscall_Accept, "accept");
 
    function Syscall_Connect
@@ -92,7 +92,7 @@ package body GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
    pragma Import (C, Syscall_Recvfrom, "recvfrom");
 
    function Syscall_Send
@@ -125,7 +125,7 @@ package body GNAT.Sockets.Thin is
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int
+      Addrlen : not null access C.int) return C.int
    is
       R   : C.int;
       Val : aliased C.int := 1;
@@ -275,7 +275,7 @@ package body GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int
+      Fromlen : not null access C.int) return C.int
    is
       Res : C.int;
 
@@ -461,6 +461,12 @@ package body GNAT.Sockets.Thin is
       Sin.Sin_Port   := Port;
    end Set_Port;
 
+   --------------------
+   -- Signalling_Fds --
+   --------------------
+
+   package body Signalling_Fds is separate;
+
    --------------------------
    -- Socket_Error_Message --
    --------------------------
diff --git a/gcc/ada/g-socthi-vms.ads b/gcc/ada/g-socthi-vms.ads
index 1b05e4719bc..c1bd1164371 100644
--- a/gcc/ada/g-socthi-vms.ads
+++ b/gcc/ada/g-socthi-vms.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---                     Copyright (C) 2002-2005, AdaCore                     --
+--                     Copyright (C) 2002-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -38,8 +38,8 @@
 --  This is the Alpha/VMS version
 
 with Interfaces.C.Pointers;
-
 with Interfaces.C.Strings;
+
 with GNAT.Sockets.Constants;
 with GNAT.OS_Lib;
 
@@ -60,9 +60,12 @@ package GNAT.Sockets.Thin is
    function Socket_Errno return Integer renames GNAT.OS_Lib.Errno;
    --  Returns last socket error number
 
+   procedure Set_Socket_Errno (Errno : Integer) renames GNAT.OS_Lib.Set_Errno;
+   --  Set last socket error number
+
    function Socket_Error_Message (Errno : Integer) return C.Strings.chars_ptr;
-   --  Returns the error message string for the error number Errno. If
-   --  Errno is not known it returns "Unknown system error".
+   --  Returns the error message string for the error number Errno. If Errno is
+   --  not known it returns "Unknown system error".
 
    function Host_Errno return Integer;
    pragma Import (C, Host_Errno, "__gnat_get_h_errno");
@@ -165,8 +168,8 @@ package GNAT.Sockets.Thin is
    --  Set Sin.Sin_Family to Family
 
    procedure Set_Port
-     (Sin     : Sockaddr_In_Access;
-      Port    : C.unsigned_short);
+     (Sin  : Sockaddr_In_Access;
+      Port : C.unsigned_short);
    pragma Inline (Set_Port);
    --  Set Sin.Sin_Port to Port
 
@@ -203,14 +206,24 @@ package GNAT.Sockets.Thin is
    pragma Convention (C, Servent_Access);
    --  Access to service entry
 
-   type Two_Int is array (0 .. 1) of C.int;
-   pragma Convention (C, Two_Int);
-   --  Used with pipe()
+   type Two_Ints is array (0 .. 1) of C.int;
+   pragma Convention (C, Two_Ints);
+   --  Container for two int values
+
+   subtype Fd_Pair is Two_Ints;
+   --  Two_Ints as used for Create_Signalling_Fds: a pair of connected file
+   --  descriptors, one of which (the "read end" of the connection) being used
+   --  for reading, the other one (the "write end") being used for writing.
+
+   Read_End  : constant := 0;
+   Write_End : constant := 1;
+   --  Indices into an Fd_Pair value providing access to each of the connected
+   --  file descriptors.
 
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
 
    function C_Bind
      (S       : C.int;
@@ -240,7 +253,7 @@ package GNAT.Sockets.Thin is
    function C_Getpeername
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getservbyname
      (Name  : C.char_array;
@@ -253,24 +266,26 @@ package GNAT.Sockets.Thin is
    function C_Getsockname
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getsockopt
      (S       : C.int;
       Level   : C.int;
       Optname : C.int;
       Optval  : System.Address;
-      Optlen  : access C.int) return C.int;
+      Optlen  : not null access C.int) return C.int;
 
    function C_Inet_Addr
-     (Cp   : C.Strings.chars_ptr) return C.int;
+     (Cp : C.Strings.chars_ptr) return C.int;
 
    function C_Ioctl
      (S    : C.int;
       Req  : C.int;
       Arg  : Int_Access) return C.int;
 
-   function C_Listen (S, Backlog : C.int) return C.int;
+   function C_Listen
+     (S       : C.int;
+      Backlog : C.int) return C.int;
 
    function C_Readv
      (Fd     : C.int;
@@ -289,7 +304,7 @@ package GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
 
    function C_Select
      (Nfds      : C.int;
@@ -320,8 +335,8 @@ package GNAT.Sockets.Thin is
       Optlen  : C.int) return C.int;
 
    function C_Shutdown
-     (S    : C.int;
-      How  : C.int) return C.int;
+     (S   : C.int;
+      How : C.int) return C.int;
 
    function C_Socket
      (Domain   : C.int;
@@ -339,6 +354,25 @@ package GNAT.Sockets.Thin is
       Iov    : System.Address;
       Iovcnt : C.int) return C.int;
 
+   package Signalling_Fds is
+
+      function Create (Fds : not null access Fd_Pair) return C.int;
+      pragma Convention (C, Create);
+      --  Create a pair of connected descriptors suitable for use with C_Select
+      --  (used for signalling in Selector objects).
+
+      function Read (Rsig : C.int) return C.int;
+      pragma Convention (C, Read);
+      --  Read one byte of data from rsig, the read end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+      function Write (Wsig : C.int) return C.int;
+      pragma Convention (C, Write);
+      --  Write one byte of data to wsig, the write end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+   end Signalling_Fds;
+
    procedure Free_Socket_Set
      (Set : Fd_Set_Access);
    --  Free system-dependent socket set
@@ -367,17 +401,17 @@ package GNAT.Sockets.Thin is
    procedure Last_Socket_In_Set
      (Set    : Fd_Set_Access;
       Last   : Int_Access);
-   --  Find the largest socket in the socket set. This is needed for
-   --  select(). When Last_Socket_In_Set is called, parameter Last is
-   --  a maximum value of the largest socket. This hint is used to
-   --  avoid scanning very large socket sets. After the call, Last is
-   --  set back to the real largest socket in the socket set.
+   --  Find the largest socket in the socket set. This is needed for select().
+   --  When Last_Socket_In_Set is called, parameter Last is a maximum value of
+   --  the largest socket. This hint is used to avoid scanning very large
+   --  socket sets. After the call, Last is set back to the real largest socket
+   --  in the socket set.
 
    function  New_Socket_Set
      (Set : Fd_Set_Access) return Fd_Set_Access;
-   --  Allocate a new socket set which is a system-dependent structure
-   --  and initialize by copying Set if it is non-null, by making it
-   --  empty otherwise.
+   --  Allocate a new socket set which is a system-dependent structure and
+   --  initialize by copying Set if it is non-null, by making it empty
+   --  otherwise.
 
    procedure Remove_Socket_From_Set
      (Set    : Fd_Set_Access;
@@ -414,4 +448,5 @@ private
    pragma Import (C, New_Socket_Set, "__gnat_new_socket_set");
    pragma Import (C, Insert_Socket_In_Set, "__gnat_insert_socket_in_set");
    pragma Import (C, Remove_Socket_From_Set, "__gnat_remove_socket_from_set");
+
 end GNAT.Sockets.Thin;
diff --git a/gcc/ada/g-socthi-vxworks.adb b/gcc/ada/g-socthi-vxworks.adb
index cb72c9fde86..e0539a9d12b 100644
--- a/gcc/ada/g-socthi-vxworks.adb
+++ b/gcc/ada/g-socthi-vxworks.adb
@@ -92,7 +92,7 @@ package body GNAT.Sockets.Thin is
    function Syscall_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
    pragma Import (C, Syscall_Accept, "accept");
 
    function Syscall_Connect
@@ -120,7 +120,7 @@ package body GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
    pragma Import (C, Syscall_Recvfrom, "recvfrom");
 
    function Syscall_Send
@@ -155,7 +155,7 @@ package body GNAT.Sockets.Thin is
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int
+      Addrlen : not null access C.int) return C.int
    is
       R   : C.int;
       Val : aliased C.int := 1;
@@ -398,7 +398,7 @@ package body GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int
+      Fromlen : not null access C.int) return C.int
    is
       Res : C.int;
 
@@ -594,6 +594,12 @@ package body GNAT.Sockets.Thin is
       Sin.Sin_Port   := Port;
    end Set_Port;
 
+   --------------------
+   -- Signalling_Fds --
+   --------------------
+
+   package body Signalling_Fds is separate;
+
    --------------------------
    -- Socket_Error_Message --
    --------------------------
diff --git a/gcc/ada/g-socthi-vxworks.ads b/gcc/ada/g-socthi-vxworks.ads
index 6aee25d4ef4..6e598b7dbc6 100644
--- a/gcc/ada/g-socthi-vxworks.ads
+++ b/gcc/ada/g-socthi-vxworks.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---                     Copyright (C) 2002-2005, AdaCore                     --
+--                     Copyright (C) 2002-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -38,9 +38,10 @@
 --  This is the version for VxWorks
 
 with Interfaces.C.Pointers;
+with Interfaces.C.Strings;
 
 with Ada.Unchecked_Conversion;
-with Interfaces.C.Strings;
+
 with GNAT.Sockets.Constants;
 with GNAT.OS_Lib;
 
@@ -59,6 +60,9 @@ package GNAT.Sockets.Thin is
    function Socket_Errno return Integer renames GNAT.OS_Lib.Errno;
    --  Returns last socket error number
 
+   procedure Set_Socket_Errno (Errno : Integer) renames GNAT.OS_Lib.Set_Errno;
+   --  Set last socket error number
+
    function Socket_Error_Message (Errno : Integer) return C.Strings.chars_ptr;
    --  Returns the error message string for the error number Errno. If Errno is
    --  not known it returns "Unknown system error".
@@ -161,20 +165,20 @@ package GNAT.Sockets.Thin is
    --  Set Sin.Sin_Length to Len
 
    procedure Set_Family
-     (Sin     : Sockaddr_In_Access;
-      Family  : C.int);
+     (Sin    : Sockaddr_In_Access;
+      Family : C.int);
    pragma Inline (Set_Family);
    --  Set Sin.Sin_Family to Family
 
    procedure Set_Port
-     (Sin     : Sockaddr_In_Access;
-      Port    : C.unsigned_short);
+     (Sin  : Sockaddr_In_Access;
+      Port : C.unsigned_short);
    pragma Inline (Set_Port);
    --  Set Sin.Sin_Port to Port
 
    procedure Set_Address
-     (Sin        : Sockaddr_In_Access;
-      Address    : In_Addr);
+     (Sin     : Sockaddr_In_Access;
+      Address : In_Addr);
    pragma Inline (Set_Address);
    --  Set Sin.Sin_Addr to Address
 
@@ -193,10 +197,10 @@ package GNAT.Sockets.Thin is
    --  Access to host entry
 
    type Servent is record
-      S_Name      : C.Strings.chars_ptr;
-      S_Aliases   : Chars_Ptr_Pointers.Pointer;
-      S_Port      : C.int;
-      S_Proto     : C.Strings.chars_ptr;
+      S_Name    : C.Strings.chars_ptr;
+      S_Aliases : Chars_Ptr_Pointers.Pointer;
+      S_Port    : C.int;
+      S_Proto   : C.Strings.chars_ptr;
    end record;
    pragma Convention (C, Servent);
    --  Service entry
@@ -205,14 +209,24 @@ package GNAT.Sockets.Thin is
    pragma Convention (C, Servent_Access);
    --  Access to service entry
 
-   type Two_Int is array (0 .. 1) of C.int;
-   pragma Convention (C, Two_Int);
-   --  Used with pipe()
+   type Two_Ints is array (0 .. 1) of C.int;
+   pragma Convention (C, Two_Ints);
+   --  Container for two int values
+
+   subtype Fd_Pair is Two_Ints;
+   --  Two_Ints as used for Create_Signalling_Fds: a pair of connected file
+   --  descriptors, one of which (the "read end" of the connection) being used
+   --  for reading, the other one (the "write end") being used for writing.
+
+   Read_End  : constant := 0;
+   Write_End : constant := 1;
+   --  Indices into an Fd_Pair value providing access to each of the connected
+   --  file descriptors.
 
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
 
    function C_Bind
      (S       : C.int;
@@ -242,7 +256,7 @@ package GNAT.Sockets.Thin is
    function C_Getpeername
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getservbyname
      (Name  : C.char_array;
@@ -255,24 +269,26 @@ package GNAT.Sockets.Thin is
    function C_Getsockname
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getsockopt
      (S       : C.int;
       Level   : C.int;
       Optname : C.int;
       Optval  : System.Address;
-      Optlen  : access C.int) return C.int;
+      Optlen  : not null access C.int) return C.int;
 
    function C_Inet_Addr
      (Cp : C.Strings.chars_ptr) return C.int;
 
    function C_Ioctl
-     (S   : C.int;
-      Req : C.int;
-      Arg : Int_Access) return C.int;
+     (S    : C.int;
+      Req  : C.int;
+      Arg  : Int_Access) return C.int;
 
-   function C_Listen (S, Backlog : C.int) return C.int;
+   function C_Listen
+     (S       : C.int;
+      Backlog : C.int) return C.int;
 
    function C_Readv
      (Fd     : C.int;
@@ -291,7 +307,7 @@ package GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
 
    function C_Select
      (Nfds      : C.int;
@@ -341,6 +357,25 @@ package GNAT.Sockets.Thin is
       Iov    : System.Address;
       Iovcnt : C.int) return C.int;
 
+   package Signalling_Fds is
+
+      function Create (Fds : not null access Fd_Pair) return C.int;
+      pragma Convention (C, Create);
+      --  Create a pair of connected descriptors suitable for use with C_Select
+      --  (used for signalling in Selector objects).
+
+      function Read (Rsig : C.int) return C.int;
+      pragma Convention (C, Read);
+      --  Read one byte of data from rsig, the read end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+      function Write (Wsig : C.int) return C.int;
+      pragma Convention (C, Write);
+      --  Write one byte of data to wsig, the write end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+   end Signalling_Fds;
+
    procedure Free_Socket_Set
      (Set : Fd_Set_Access);
    --  Free system-dependent socket set
@@ -369,17 +404,17 @@ package GNAT.Sockets.Thin is
    procedure Last_Socket_In_Set
      (Set    : Fd_Set_Access;
       Last   : Int_Access);
-   --  Find the largest socket in the socket set. This is needed for
-   --  select(). When Last_Socket_In_Set is called, parameter Last is
-   --  a maximum value of the largest socket. This hint is used to
-   --  avoid scanning very large socket sets. After the call, Last is
-   --  set back to the real largest socket in the socket set.
+   --  Find the largest socket in the socket set. This is needed for select().
+   --  When Last_Socket_In_Set is called, parameter Last is a maximum value of
+   --  the largest socket. This hint is used to avoid scanning very large
+   --  socket sets. After the call, Last is set back to the real largest socket
+   --  in the socket set.
 
    function  New_Socket_Set
      (Set : Fd_Set_Access) return Fd_Set_Access;
-   --  Allocate a new socket set which is a system-dependent structure
-   --  and initialize by copying Set if it is non-null, by making it
-   --  empty otherwise.
+   --  Allocate a new socket set which is a system-dependent structure and
+   --  initialize by copying Set if it is non-null, by making it empty
+   --  otherwise.
 
    procedure Remove_Socket_From_Set
      (Set    : Fd_Set_Access;
@@ -390,7 +425,6 @@ package GNAT.Sockets.Thin is
    procedure Initialize (Process_Blocking_IO : Boolean);
 
 private
-
    pragma Import (C, C_Bind, "bind");
    pragma Import (C, C_Close, "close");
    pragma Import (C, C_Gethostname, "gethostname");
diff --git a/gcc/ada/g-socthi.adb b/gcc/ada/g-socthi.adb
index 914b787a41c..7ca1c1cdfdf 100644
--- a/gcc/ada/g-socthi.adb
+++ b/gcc/ada/g-socthi.adb
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 B o d y                                  --
 --                                                                          --
---                     Copyright (C) 2001-2005, AdaCore                     --
+--                     Copyright (C) 2001-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -71,7 +71,7 @@ package body GNAT.Sockets.Thin is
    function Syscall_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
    pragma Import (C, Syscall_Accept, "accept");
 
    function Syscall_Connect
@@ -99,7 +99,7 @@ package body GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
    pragma Import (C, Syscall_Recvfrom, "recvfrom");
 
    function Syscall_Send
@@ -127,6 +127,11 @@ package body GNAT.Sockets.Thin is
    procedure Disable_SIGPIPE (S : C.int);
    pragma Import (C, Disable_SIGPIPE, "__gnat_disable_sigpipe");
 
+   procedure Disable_All_SIGPIPEs;
+   pragma Import (C, Disable_All_SIGPIPEs, "__gnat_disable_all_sigpipes");
+   --  Sets the process to ignore all SIGPIPE signals on platforms that
+   --  don't support Disable_SIGPIPE for particular streams.
+
    function Non_Blocking_Socket (S : C.int) return Boolean;
    procedure Set_Non_Blocking_Socket (S : C.int; V : Boolean);
 
@@ -137,7 +142,7 @@ package body GNAT.Sockets.Thin is
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int
+      Addrlen : not null access C.int) return C.int
    is
       R   : C.int;
       Val : aliased C.int := 1;
@@ -288,7 +293,7 @@ package body GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int
+      Fromlen : not null access C.int) return C.int
    is
       Res : C.int;
 
@@ -404,6 +409,7 @@ package body GNAT.Sockets.Thin is
    procedure Initialize (Process_Blocking_IO : Boolean) is
    begin
       Thread_Blocking_IO := not Process_Blocking_IO;
+      Disable_All_SIGPIPEs;
    end Initialize;
 
    -------------------------
@@ -487,6 +493,32 @@ package body GNAT.Sockets.Thin is
       Sin.Sin_Port   := Port;
    end Set_Port;
 
+   --------------------
+   -- Signalling_Fds --
+   --------------------
+
+   package body Signalling_Fds is
+
+      --  In this default implementation, we use a C version of these
+      --  subprograms provided by socket.c.
+
+      function C_Create (Fds : not null access Fd_Pair) return C.int;
+      function C_Read (Rsig : C.int) return C.int;
+      function C_Write (Wsig : C.int) return C.int;
+
+      pragma Import (C, C_Create, "__gnat_create_signalling_fds");
+      pragma Import (C, C_Read,   "__gnat_read_signalling_fd");
+      pragma Import (C, C_Write,  "__gnat_write_signalling_fd");
+
+      function Create (Fds : not null access Fd_Pair) return C.int
+        renames C_Create;
+
+      function Read (Rsig : C.int) return C.int renames C_Read;
+
+      function Write (Wsig : C.int) return C.int renames C_Write;
+
+   end Signalling_Fds;
+
    --------------------------
    -- Socket_Error_Message --
    --------------------------
diff --git a/gcc/ada/g-socthi.ads b/gcc/ada/g-socthi.ads
index 5d06d99bcae..ce3f7586f1b 100644
--- a/gcc/ada/g-socthi.ads
+++ b/gcc/ada/g-socthi.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---                     Copyright (C) 2001-2005, AdaCore                     --
+--                     Copyright (C) 2001-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -39,6 +39,7 @@
 
 with Interfaces.C.Pointers;
 with Interfaces.C.Strings;
+
 with GNAT.Sockets.Constants;
 with GNAT.OS_Lib;
 
@@ -204,14 +205,24 @@ package GNAT.Sockets.Thin is
    pragma Convention (C, Servent_Access);
    --  Access to service entry
 
-   type Two_Int is array (0 .. 1) of C.int;
-   pragma Convention (C, Two_Int);
-   --  Used with pipe()
+   type Two_Ints is array (0 .. 1) of C.int;
+   pragma Convention (C, Two_Ints);
+   --  Container for two int values
+
+   subtype Fd_Pair is Two_Ints;
+   --  Two_Ints as used for Create_Signalling_Fds: a pair of connected file
+   --  descriptors, one of which (the "read end" of the connection) being used
+   --  for reading, the other one (the "write end") being used for writing.
+
+   Read_End  : constant := 0;
+   Write_End : constant := 1;
+   --  Indices into an Fd_Pair value providing access to each of the connected
+   --  file descriptors.
 
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
-      Addrlen : access C.int) return C.int;
+      Addrlen : not null access C.int) return C.int;
 
    function C_Bind
      (S       : C.int;
@@ -241,7 +252,7 @@ package GNAT.Sockets.Thin is
    function C_Getpeername
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getservbyname
      (Name  : C.char_array;
@@ -254,14 +265,14 @@ package GNAT.Sockets.Thin is
    function C_Getsockname
      (S       : C.int;
       Name    : System.Address;
-      Namelen : access C.int) return C.int;
+      Namelen : not null access C.int) return C.int;
 
    function C_Getsockopt
      (S       : C.int;
       Level   : C.int;
       Optname : C.int;
       Optval  : System.Address;
-      Optlen  : access C.int) return C.int;
+      Optlen  : not null access C.int) return C.int;
 
    function C_Inet_Addr
      (Cp : C.Strings.chars_ptr) return C.int;
@@ -292,7 +303,7 @@ package GNAT.Sockets.Thin is
       Len     : C.int;
       Flags   : C.int;
       From    : Sockaddr_In_Access;
-      Fromlen : access C.int) return C.int;
+      Fromlen : not null access C.int) return C.int;
 
    function C_Select
      (Nfds      : C.int;
@@ -342,6 +353,25 @@ package GNAT.Sockets.Thin is
       Iov    : System.Address;
       Iovcnt : C.int) return C.int;
 
+   package Signalling_Fds is
+
+      function Create (Fds : not null access Fd_Pair) return C.int;
+      pragma Convention (C, Create);
+      --  Create a pair of connected descriptors suitable for use with C_Select
+      --  (used for signalling in Selector objects).
+
+      function Read (Rsig : C.int) return C.int;
+      pragma Convention (C, Read);
+      --  Read one byte of data from rsig, the read end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+      function Write (Wsig : C.int) return C.int;
+      pragma Convention (C, Write);
+      --  Write one byte of data to wsig, the write end of a pair of signalling
+      --  fds created by Create_Signalling_Fds.
+
+   end Signalling_Fds;
+
    procedure Free_Socket_Set
      (Set : Fd_Set_Access);
    --  Free system-dependent socket set
@@ -418,4 +448,5 @@ private
    pragma Import (C, New_Socket_Set, "__gnat_new_socket_set");
    pragma Import (C, Insert_Socket_In_Set, "__gnat_insert_socket_in_set");
    pragma Import (C, Remove_Socket_From_Set, "__gnat_remove_socket_from_set");
+
 end GNAT.Sockets.Thin;
diff --git a/gcc/ada/g-soliop-mingw.ads b/gcc/ada/g-soliop-mingw.ads
index 2966df635e5..039d3754c04 100644
--- a/gcc/ada/g-soliop-mingw.ads
+++ b/gcc/ada/g-soliop-mingw.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---                     Copyright (C) 2001-2005, AdaCore                     --
+--                     Copyright (C) 2001-2006, AdaCore                     --
 --                                                                          --
 -- 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- --
@@ -38,5 +38,5 @@
 
 package GNAT.Sockets.Linker_Options is
 private
-   pragma Linker_Options ("-lwsock32");
+   pragma Linker_Options ("-lws2_32");
 end GNAT.Sockets.Linker_Options;
diff --git a/gcc/ada/g-stsifd-sockets.adb b/gcc/ada/g-stsifd-sockets.adb
new file mode 100644
index 00000000000..eb480b90328
--- /dev/null
+++ b/gcc/ada/g-stsifd-sockets.adb
@@ -0,0 +1,191 @@
+------------------------------------------------------------------------------
+--                                                                          --
+--                         GNAT COMPILER COMPONENTS                         --
+--                                                                          --
+--     G N A T . S O C K E T S . T H I N . S I G N A L L I N G _ F D S      --
+--                                                                          --
+--                                 B o d y                                  --
+--                                                                          --
+--                     Copyright (C) 2001-2006, AdaCore                     --
+--                                                                          --
+-- 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 2,  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.  See the GNU General Public License --
+-- for  more details.  You should have  received  a copy of the GNU General --
+-- Public License  distributed with GNAT;  see file COPYING.  If not, write --
+-- to  the  Free Software Foundation,  51  Franklin  Street,  Fifth  Floor, --
+-- Boston, MA 02110-1301, USA.                                              --
+--                                                                          --
+-- As a special exception,  if other files  instantiate  generics from this --
+-- unit, or you link  this unit with other files  to produce an executable, --
+-- this  unit  does not  by itself cause  the resulting  executable  to  be --
+-- covered  by the  GNU  General  Public  License.  This exception does not --
+-- however invalidate  any other reasons why  the executable file  might be --
+-- covered by the  GNU Public License.                                      --
+--                                                                          --
+-- GNAT was originally developed  by the GNAT team at  New York University. --
+-- Extensive contributions were provided by Ada Core Technologies Inc.      --
+--                                                                          --
+------------------------------------------------------------------------------
+
+--  Portable sockets-based implementation of GNAT.Sockets.Thin.Signalling_Fds
+--  used for platforms that do not support UNIX pipes.
+
+--  Note: this code used to be in GNAT.Sockets, but has been moved to a
+--  platform-specific file. It is now used only for non-UNIX platforms.
+
+separate
+  (GNAT.Sockets.Thin)
+package body Signalling_Fds is
+
+   ------------
+   -- Create --
+   ------------
+
+   function Create (Fds : not null access Fd_Pair) return C.int is
+      L_Sock, R_Sock, W_Sock : C.int := Failure;
+      --  Listening socket, read socket and write socket
+
+      Sin : aliased Sockaddr_In;
+      Len : aliased C.int := Sin'Size / 8;
+      --  Address of listening socket
+
+      Res : C.int;
+      --  Return status of system calls
+
+      Err : Integer;
+      --  Saved errno value
+
+   begin
+      Fds (Read_End)  := Failure;
+      Fds (Write_End) := Failure;
+
+      --  We open two signalling sockets. One of them is used to send data
+      --  to the other, which is included in a C_Select socket set. The
+      --  communication is used to force the call to C_Select to complete,
+      --  and the waiting task to resume its execution.
+
+      --  Create a listening socket
+
+      L_Sock := C_Socket (Constants.AF_INET, Constants.SOCK_STREAM, 0);
+
+      if L_Sock = Failure then
+         goto Fail;
+      end if;
+
+      --  Bind the socket to an available port on localhost
+
+      Sin.Sin_Addr.S_B1 := 127;
+      Sin.Sin_Addr.S_B2 := 0;
+      Sin.Sin_Addr.S_B3 := 0;
+      Sin.Sin_Addr.S_B4 := 1;
+      Sin.Sin_Port := 0;
+
+      Res := C_Bind (L_Sock, Sin'Address, Len);
+
+      if Res = Failure then
+         goto Fail;
+      end if;
+
+      --  Get assigned port
+
+      Res := C_Getsockname (L_Sock, Sin'Address, Len'Access);
+      if Res = Failure then
+         goto Fail;
+      end if;
+
+      --  Set socket to listen mode, with a backlog of 1 to guarantee that
+      --  exactly one call to connect(2) succeeds.
+
+      Res := C_Listen (L_Sock, 1);
+
+      if Res = Failure then
+         goto Fail;
+      end if;
+
+      --  Create read end (client) socket
+
+      R_Sock := C_Socket (Constants.AF_INET, Constants.SOCK_STREAM, 0);
+
+      if R_Sock = Failure then
+         goto Fail;
+      end if;
+
+      --  Connect listening socket
+
+      Res := C_Connect (R_Sock, Sin'Address, Len);
+
+      if Res = Failure then
+         goto Fail;
+      end if;
+
+      --  Since the call to connect(2) has suceeded and the backlog limit on
+      --  the listening socket is 1, we know that there is now exactly one
+      --  pending connection on L_Sock, which is the one from R_Sock.
+
+      W_Sock := C_Accept (L_Sock, Sin'Address, Len'Access);
+      if W_Sock = Failure then
+         goto Fail;
+      end if;
+
+      --  Set TCP_NODELAY on W_Sock, since we always want to send the data out
+      --  immediately.
+
+      Set_Socket_Option
+        (Socket => Socket_Type (W_Sock),
+         Level  => IP_Protocol_For_TCP_Level,
+         Option => (Name => No_Delay, Enabled => True));
+
+      --  Close listening socket (ignore exit status)
+
+      Res := C_Close (L_Sock);
+
+      Fds (Read_End)  := R_Sock;
+      Fds (Write_End) := W_Sock;
+
+      return Success;
+
+   <<Fail>>
+      Err := Socket_Errno;
+
+      if W_Sock /= Failure then
+         Res := C_Close (W_Sock);
+      end if;
+
+      if R_Sock /= Failure then
+         Res := C_Close (R_Sock);
+      end if;
+
+      if L_Sock /= Failure then
+         Res := C_Close (L_Sock);
+      end if;
+
+      Set_Socket_Errno (Err);
+
+      return Failure;
+   end Create;
+
+   ----------
+   -- Read --
+   ----------
+
+   function Read (Rsig : C.int) return C.int is
+      Buf : aliased Character;
+   begin
+      return C_Recv (Rsig, Buf'Address, 1, Constants.MSG_Forced_Flags);
+   end Read;
+
+   -----------
+   -- Write --
+   -----------
+
+   function Write (Wsig : C.int) return C.int is
+      Buf : aliased Character := ASCII.NUL;
+   begin
+      return C_Send (Wsig, Buf'Address, 1, Constants.MSG_Forced_Flags);
+   end Write;
+
+end Signalling_Fds;
diff --git a/gcc/ada/socket.c b/gcc/ada/socket.c
index bb79ac30a72..ef8e26581a7 100644
--- a/gcc/ada/socket.c
+++ b/gcc/ada/socket.c
@@ -6,7 +6,7 @@
  *                                                                          *
  *                          C Implementation File                           *
  *                                                                          *
- *          Copyright (C) 2003-2005 Free Software Foundation, Inc.          *
+ *          Copyright (C) 2003-2006, 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- *
@@ -36,6 +36,11 @@
 /* Include all the necessary system-specific headers and define the
    necessary macros (shared with gen-soccon). */
 
+#if !defined(SO_NOSIGPIPE) && !defined (MSG_NOSIGNAL)
+#include <signal.h>
+#endif
+/* Required if we will be calling signal() in __gnat_disable_all_sigpipes() */
+
 #include "raise.h"
 /* Required for __gnat_malloc() */
 
@@ -43,6 +48,10 @@
 /* Required for memcpy() */
 
 extern void __gnat_disable_sigpipe (int fd);
+extern void __gnat_disable_all_sigpipes (void);
+extern int  __gnat_create_signalling_fds (int *fds);
+extern int  __gnat_read_signalling_fd (int rsig);
+extern int  __gnat_write_signalling_fd (int wsig);
 extern void __gnat_free_socket_set (fd_set *);
 extern void __gnat_last_socket_in_set (fd_set *, int *);
 extern void __gnat_get_socket_from_set (fd_set *, int *, int *);
@@ -50,7 +59,7 @@ extern void __gnat_insert_socket_in_set (fd_set *, int);
 extern int __gnat_is_socket_in_set (fd_set *, int);
 extern fd_set *__gnat_new_socket_set (fd_set *);
 extern void __gnat_remove_socket_from_set (fd_set *, int);
-extern int __gnat_get_h_errno (void);
+extern int  __gnat_get_h_errno (void);
 
 /* Disable the sending of SIGPIPE for writes on a broken stream */
 
@@ -63,6 +72,51 @@ __gnat_disable_sigpipe (int fd)
 #endif
 }
 
+void
+__gnat_disable_all_sigpipes (void)
+{
+#if !defined(SO_NOSIGPIPE) && !defined(MSG_NOSIGNAL) && defined(SIGPIPE)
+  (void) signal (SIGPIPE, SIG_IGN);
+#endif
+}
+
+#if defined (_WIN32) || defined (__vxworks) || defined (VMS)
+/*
+ * Signalling FDs operations are implemented in Ada for these platforms
+ * (see subunit GNAT.Sockets.Thin.Signalling_Fds).
+ */
+#else
+/*
+ * Create a pair of connected file descriptors fds[0] and fds[1] used for
+ * signalling by a Selector object. fds[0] is the read end, and fds[1] the
+ * write end.
+ */
+int
+__gnat_create_signalling_fds (int *fds) {
+  return pipe (fds);
+}
+
+/*
+ * Read one byte of data from rsig, the read end of a pair of signalling fds
+ * created by __gnat_create_signalling_fds.
+ */
+int
+__gnat_read_signalling_fd (int rsig) {
+  char c;
+  return read (rsig, &c, 1);
+}
+
+/*
+ * Write one byte of data to wsig, the write end of a pair of signalling fds
+ * created by __gnat_create_signalling_fds.
+ */
+int
+__gnat_write_signalling_fd (int wsig) {
+  char c = 0;
+  return write (wsig, &c, 1);
+}
+#endif
+
 /* Free socket set. */
 
 void
@@ -83,7 +137,7 @@ __gnat_last_socket_in_set (fd_set *set, int *last)
   int l;
   l = -1;
 
-#ifdef WINNT
+#ifdef _WIN32
   /* More efficient method for NT. */
   for (s = 0; s < set->fd_count; s++)
     if ((int) set->fd_array[s] > l)