g-soccon.ads: Add new constant Thread_Blocking_IO...

2007-04-20  Thomas Quinot  <quinot@adacore.com>

	* g-soccon.ads: Add new constant Thread_Blocking_IO, always True by
	default, set False on a per-runtime basis.
	(Need_Netdb_Buffer): New constant.

	* g-socket.ads, g-socket.adb: Import new package
	GNAT.Sockets.Thin.Task_Safe_NetDB.
	(Raise_Host_Error): Use Host_Error_Message from platform-specific thin
	binding to obtain proper message.
	(Close_Selector): Use GNAT.Sockets.Thin.Signalling_Fds.Close.
	Replace various occurrences of Arry (Arry'First)'Address with the
	equivalent Arry'Address (GNAT always follows implementation advice from
	13.3(14)).
	(Get_Host_By_Address, Get_Host_By_Name,
	Get_Service_By_Name, Get_Service_By_Port): Do not use GNAT.Task_Lock;
	instead, rely on platform-specific task safe netdb operations provided
	by g-socthi.

	* g-socthi.ads, g-socthi.adb (Initialize): Remove obsolete formal
	parameter Process_Blocking_IO.
	(Host_Error_Messages): Add stub body.
	(GNAT.Sockets.Thin.Signalling_Fds): New procedure Close.
	(Safe_Gethostbyname, Safe_Gethostbyaddr, Safe_Getservbyname,
	Safe_Getservbyport): Move functions into new child package
	Task_Safe_NetDB.
	(Nonreentrant_Gethostbyname, Nonreentrant_Gethostbyaddr,
	Nonreentrant_Getservbyname, Nonreentrant_Getservbyport): New routines.
	(In_Addr): Add alignment clause.

From-SVN: r125424

1 files changed, 67 insertions, 30 deletions

diff --git a/gcc/ada/g-socthi.ads b/gcc/ada/g-socthi.ads
index ce3f758..59e9004 100644
--- a/gcc/ada/g-socthi.ads
+++ b/gcc/ada/g-socthi.ads
@@ -6,7 +6,7 @@
 --                                                                          --
 --                                 S p e c                                  --
 --                                                                          --
---                     Copyright (C) 2001-2006, AdaCore                     --
+--                     Copyright (C) 2001-2007, 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- --
@@ -40,8 +40,8 @@
 with Interfaces.C.Pointers;
 with Interfaces.C.Strings;
 
-with GNAT.Sockets.Constants;
 with GNAT.OS_Lib;
+with GNAT.Sockets.Constants;
 
 with System;
 
@@ -64,12 +64,21 @@ package GNAT.Sockets.Thin is
 
    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".
+   --  not known, returns "Unknown system error".
 
    function Host_Errno return Integer;
    pragma Import (C, Host_Errno, "__gnat_get_h_errno");
    --  Returns last host error number
 
+   package Host_Error_Messages is
+
+      function Host_Error_Message
+        (H_Errno : Integer) return C.Strings.chars_ptr;
+      --  Returns the error message string for the host error number H_Errno.
+      --  If H_Errno is not known, returns "Unknown system error".
+
+   end Host_Error_Messages;
+
    subtype Fd_Set_Access is System.Address;
    No_Fd_Set : constant Fd_Set_Access := System.Null_Address;
 
@@ -111,8 +120,11 @@ package GNAT.Sockets.Thin is
    type In_Addr is record
       S_B1, S_B2, S_B3, S_B4 : C.unsigned_char;
    end record;
+   for In_Addr'Alignment use C.int'Alignment;
    pragma Convention (C, In_Addr);
-   --  Internet address
+   --  IPv4 address, represented as a network-order C.int. Note that the
+   --  underlying operating system may assume that values of this type have
+   --  C.int alignment, so we need to provide a suitable alignment clause here.
 
    type In_Addr_Access is access all In_Addr;
    pragma Convention (C, In_Addr_Access);
@@ -219,6 +231,10 @@ package GNAT.Sockets.Thin is
    --  Indices into an Fd_Pair value providing access to each of the connected
    --  file descriptors.
 
+   --------------------------------
+   -- Standard library functions --
+   --------------------------------
+
    function C_Accept
      (S       : C.int;
       Addr    : System.Address;
@@ -237,14 +253,6 @@ package GNAT.Sockets.Thin is
       Name    : System.Address;
       Namelen : C.int) return C.int;
 
-   function C_Gethostbyaddr
-     (Addr : System.Address;
-      Len  : C.int;
-      Typ  : C.int) return Hostent_Access;
-
-   function C_Gethostbyname
-     (Name : C.char_array) return Hostent_Access;
-
    function C_Gethostname
      (Name    : System.Address;
       Namelen : C.int) return C.int;
@@ -254,14 +262,6 @@ package GNAT.Sockets.Thin is
       Name    : System.Address;
       Namelen : not null access C.int) return C.int;
 
-   function C_Getservbyname
-     (Name  : C.char_array;
-      Proto : C.char_array) return Servent_Access;
-
-   function C_Getservbyport
-     (Port  : C.int;
-      Proto : C.char_array) return Servent_Access;
-
    function C_Getsockname
      (S       : C.int;
       Name    : System.Address;
@@ -353,6 +353,10 @@ package GNAT.Sockets.Thin is
       Iov    : System.Address;
       Iovcnt : C.int) return C.int;
 
+   -------------------------------------------------------
+   -- Signalling file descriptors for selector abortion --
+   -------------------------------------------------------
+
    package Signalling_Fds is
 
       function Create (Fds : not null access Fd_Pair) return C.int;
@@ -370,8 +374,16 @@ package GNAT.Sockets.Thin is
       --  Write one byte of data to wsig, the write end of a pair of signalling
       --  fds created by Create_Signalling_Fds.
 
+      procedure Close (Sig : C.int);
+      pragma Convention (C, Close);
+      --  Close one end of a pair of signalling fds (ignoring any error)
+
    end Signalling_Fds;
 
+   ----------------------------
+   -- Socket sets management --
+   ----------------------------
+
    procedure Free_Socket_Set
      (Set : Fd_Set_Access);
    --  Free system-dependent socket set
@@ -380,11 +392,11 @@ package GNAT.Sockets.Thin is
      (Set    : Fd_Set_Access;
       Socket : Int_Access;
       Last   : Int_Access);
-   --  Get last socket in Socket and remove it from the socket
-   --  set. The parameter Last is a maximum value of the largest
-   --  socket. This hint is used to avoid scanning very large socket
-   --  sets. After a call to Get_Socket_From_Set, Last is set back to
-   --  the real largest socket in the socket set.
+   --  Get last socket in Socket and remove it from the socket set. The
+   --  parameter Last is a maximum value of the largest socket. This hint is
+   --  used to avoid scanning very large socket sets. After a call to
+   --  Get_Socket_From_Set, Last is set back to the real largest socket in the
+   --  socket set.
 
    procedure Insert_Socket_In_Set
      (Set    : Fd_Set_Access;
@@ -417,18 +429,38 @@ package GNAT.Sockets.Thin is
       Socket : C.int);
    --  Remove socket from the socket set
 
+   -------------------------------------------
+   -- Nonreentrant network databases access --
+   -------------------------------------------
+
+   --  The following are used only on systems that have nonreentrant
+   --  getXXXbyYYY functions, and do NOT have corresponding getXXXbyYYY_
+   --  functions. Currently, LynxOS is the only such system.
+
+   function Nonreentrant_Gethostbyname
+     (Name : C.char_array) return Hostent_Access;
+
+   function Nonreentrant_Gethostbyaddr
+     (Addr      : System.Address;
+      Addr_Len  : C.int;
+      Addr_Type : C.int) return Hostent_Access;
+
+   function Nonreentrant_Getservbyname
+     (Name  : C.char_array;
+      Proto : C.char_array) return Servent_Access;
+
+   function Nonreentrant_Getservbyport
+     (Port  : C.int;
+      Proto : C.char_array) return Servent_Access;
+
+   procedure Initialize;
    procedure Finalize;
-   procedure Initialize (Process_Blocking_IO : Boolean);
 
 private
    pragma Import (C, C_Bind, "bind");
    pragma Import (C, C_Close, "close");
-   pragma Import (C, C_Gethostbyaddr, "gethostbyaddr");
-   pragma Import (C, C_Gethostbyname, "gethostbyname");
    pragma Import (C, C_Gethostname, "gethostname");
    pragma Import (C, C_Getpeername, "getpeername");
-   pragma Import (C, C_Getservbyname, "getservbyname");
-   pragma Import (C, C_Getservbyport, "getservbyport");
    pragma Import (C, C_Getsockname, "getsockname");
    pragma Import (C, C_Getsockopt, "getsockopt");
    pragma Import (C, C_Inet_Addr, "inet_addr");
@@ -449,4 +481,9 @@ private
    pragma Import (C, Insert_Socket_In_Set, "__gnat_insert_socket_in_set");
    pragma Import (C, Remove_Socket_From_Set, "__gnat_remove_socket_from_set");
 
+   pragma Import (C, Nonreentrant_Gethostbyname, "gethostbyname");
+   pragma Import (C, Nonreentrant_Gethostbyaddr, "gethostbyaddr");
+   pragma Import (C, Nonreentrant_Getservbyname, "getservbyname");
+   pragma Import (C, Nonreentrant_Getservbyport, "getservbyport");
+
 end GNAT.Sockets.Thin;