[COMMITTED] ada: Add support for binding to a specific network interface controller.

[COMMITTED] ada: Add support for binding to a specific network interface controller.

[Marc Poulhiès]

From: Pascal Obry <obry@adacore.com>

gcc/ada/

	* s-oscons-tmplt.c: Add support for SO_BINDTODEVICE constant.
	* libgnat/g-socket.ads (Set_Socket_Option): Handle SO_BINDTODEVICE option.
	(Get_Socket_Option): Handle SO_BINDTODEVICE option.
	* libgnat/g-socket.adb: Likewise.
	(Get_Socket_Option): Handle the case where IF_NAMESIZE is not defined
	and so equal to -1.

Tested on x86_64-pc-linux-gnu, committed on master.

---
 gcc/ada/libgnat/g-socket.adb | 26 ++++++++++++++++++++++++--
 gcc/ada/libgnat/g-socket.ads |  5 +++++
 gcc/ada/s-oscons-tmplt.c     |  5 +++++
 3 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/gcc/ada/libgnat/g-socket.adb b/gcc/ada/libgnat/g-socket.adb
index dca696f7c5f..c4e29075a0b 100644
--- a/gcc/ada/libgnat/g-socket.adb
+++ b/gcc/ada/libgnat/g-socket.adb
@@ -120,7 +120,8 @@ package body GNAT.Sockets is
                 IPv6_Only           => SOSC.IPV6_V6ONLY,
                 Send_Timeout        => SOSC.SO_SNDTIMEO,
                 Receive_Timeout     => SOSC.SO_RCVTIMEO,
-                Busy_Polling        => SOSC.SO_BUSY_POLL];
+                Busy_Polling        => SOSC.SO_BUSY_POLL,
+                Bind_To_Device      => SOSC.SO_BINDTODEVICE];
    --  ??? Note: for OpenSolaris, Receive_Packet_Info should be IP_RECVPKTINFO,
    --  but for Linux compatibility this constant is the same as IP_PKTINFO.
 
@@ -1413,17 +1414,21 @@ package body GNAT.Sockets is
       use type C.unsigned;
       use type C.unsigned_char;
 
+      --  SOSC.IF_NAMESIZE may be not defined, ensure that we have at least
+      --  a valid range for VS declared below.
+      NS  : constant Interfaces.C.size_t :=
+              (if SOSC.IF_NAMESIZE = -1 then 256 else SOSC.IF_NAMESIZE);
       V8  : aliased Two_Ints;
       V4  : aliased C.int;
       U4  : aliased C.unsigned;
       V1  : aliased C.unsigned_char;
+      VS  : aliased C.char_array (1 .. NS); -- for devices name
       VT  : aliased Timeval;
       Len : aliased C.int;
       Add : System.Address;
       Res : C.int;
       Opt : Option_Type (Name);
       Onm : Interfaces.C.int;
-
    begin
       if Name in Specific_Option_Name then
          Onm := Options (Name);
@@ -1491,6 +1496,11 @@ package body GNAT.Sockets is
          =>
             Len := V8'Size / 8;
             Add := V8'Address;
+
+         when Bind_To_Device
+         =>
+            Len := VS'Length;
+            Add := VS'Address;
       end case;
 
       Res :=
@@ -1589,6 +1599,9 @@ package body GNAT.Sockets is
             else
                Opt.Timeout := To_Duration (VT);
             end if;
+
+         when Bind_To_Device =>
+            Opt.Device := ASU.To_Unbounded_String (C.To_Ada (VS));
       end case;
 
       return Opt;
@@ -2616,6 +2629,10 @@ package body GNAT.Sockets is
       V4  : aliased C.int;
       U4  : aliased C.unsigned;
       V1  : aliased C.unsigned_char;
+      VS  : aliased C.char_array
+              (1 .. (if Option.Name = Bind_To_Device
+                     then C.size_t (ASU.Length (Option.Device) + 1)
+                     else 0));
       VT  : aliased Timeval;
       Len : C.int;
       Add : System.Address := Null_Address;
@@ -2754,6 +2771,11 @@ package body GNAT.Sockets is
                Len := VT'Size / 8;
                Add := VT'Address;
             end if;
+
+         when Bind_To_Device =>
+            VS := C.To_C (ASU.To_String (Option.Device));
+            Len := C.int (VS'Length);
+            Add := VS'Address;
       end case;
 
       if Option.Name in Specific_Option_Name then
diff --git a/gcc/ada/libgnat/g-socket.ads b/gcc/ada/libgnat/g-socket.ads
index d49245290ce..90740ec65a4 100644
--- a/gcc/ada/libgnat/g-socket.ads
+++ b/gcc/ada/libgnat/g-socket.ads
@@ -841,6 +841,9 @@ package GNAT.Sockets is
       --  Sets the approximate time in microseconds to busy poll on a blocking
       --  receive when there is no data.
 
+      Bind_To_Device,  -- SO_BINDTODEVICE
+      --  Bind to a specific NIC (Network Interface Controller)
+
       -------------------------------
       -- IP_Protocol_For_TCP_Level --
       -------------------------------
@@ -986,6 +989,8 @@ package GNAT.Sockets is
               Receive_Timeout =>
             Timeout : Timeval_Duration;
 
+         when Bind_To_Device =>
+            Device : Ada.Strings.Unbounded.Unbounded_String;
       end case;
    end record;
 
diff --git a/gcc/ada/s-oscons-tmplt.c b/gcc/ada/s-oscons-tmplt.c
index 28d42c5a459..fb6bb0f043b 100644
--- a/gcc/ada/s-oscons-tmplt.c
+++ b/gcc/ada/s-oscons-tmplt.c
@@ -1545,6 +1545,11 @@ CND(SO_KEEPALIVE, "Enable keep-alive msgs")
 #endif
 CND(SO_LINGER, "Defer close to flush data")
 
+#ifndef SO_BINDTODEVICE
+# define SO_BINDTODEVICE -1
+#endif
+CND(SO_BINDTODEVICE, "Bind to a NIC - Network Interface Controller")
+
 #ifndef SO_BROADCAST
 # define SO_BROADCAST -1
 #endif
-- 
2.40.0