From 554fd8c5195424bdbcabf5de30fdc183aba391bd Mon Sep 17 00:00:00 2001 From: upstream source tree Date: Sun, 15 Mar 2015 20:14:05 -0400 Subject: obtained gcc-4.6.4.tar.bz2 from upstream website; verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository. --- gcc/ada/g-stsifd-sockets.adb | 236 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 236 insertions(+) create mode 100644 gcc/ada/g-stsifd-sockets.adb (limited to 'gcc/ada/g-stsifd-sockets.adb') diff --git a/gcc/ada/g-stsifd-sockets.adb b/gcc/ada/g-stsifd-sockets.adb new file mode 100644 index 000000000..3e3f45188 --- /dev/null +++ b/gcc/ada/g-stsifd-sockets.adb @@ -0,0 +1,236 @@ +------------------------------------------------------------------------------ +-- -- +-- 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) 2001-2008, 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 + + ----------- + -- Close -- + ----------- + + procedure Close (Sig : C.int) is + Res : C.int; + pragma Unreferenced (Res); + -- Res is assigned but never read, because we purposefully ignore + -- any error returned by the C_Close system call, as per the spec + -- of this procedure. + begin + Res := C_Close (Sig); + end Close; + + ------------ + -- 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; + -- Address of listening socket + + Res : C.int; + pragma Warnings (Off, Res); + -- Return status of system calls (usually ignored, hence warnings off) + + begin + Fds.all := (Read_End | 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. + + loop + -- Retry loop, in case the C_Connect below fails + + -- Create a listening socket + + L_Sock := C_Socket (SOSC.AF_INET, SOSC.SOCK_STREAM, 0); + + if L_Sock = Failure then + goto Fail; + end if; + + -- Bind the socket to an available port on localhost + + Set_Family (Sin.Sin_Family, Family_Inet); + 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; + + Len := C.int (Lengths (Family_Inet)); + 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 (SOSC.AF_INET, SOSC.SOCK_STREAM, 0); + + if R_Sock = Failure then + goto Fail; + end if; + + -- Connect listening socket + + Res := C_Connect (R_Sock, Sin'Address, Len); + + exit when Res /= Failure; + + if Socket_Errno /= SOSC.EADDRINUSE then + goto Fail; + end if; + + -- In rare cases, the above C_Bind chooses a port that is still + -- marked "in use", even though it has been closed (perhaps by some + -- other process that has already exited). This causes the above + -- C_Connect to fail with EADDRINUSE. In this case, we close the + -- ports, and loop back to try again. This mysterious Windows + -- behavior is documented. See, for example: + -- http://msdn2.microsoft.com/en-us/library/ms737625.aspx + -- In an experiment with 2000 calls, 21 required exactly one retry, 7 + -- required two, and none required three or more. Note that no delay + -- is needed between retries; retrying C_Bind will typically produce + -- a different port. + + pragma Assert (Res = Failure + and then + Socket_Errno = SOSC.EADDRINUSE); + Res := C_Close (W_Sock); + W_Sock := Failure; + Res := C_Close (R_Sock); + R_Sock := Failure; + end loop; + + -- Since the call to connect(2) has succeeded 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.all := (Read_End => R_Sock, Write_End => W_Sock); + + return Thin_Common.Success; + + <> + declare + Saved_Errno : constant Integer := Socket_Errno; + + begin + 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 (Saved_Errno); + end; + + 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, SOSC.MSG_Forced_Flags); + end Read; + + ----------- + -- Write -- + ----------- + + function Write (Wsig : C.int) return C.int is + Buf : aliased Character := ASCII.NUL; + begin + return C_Sendto + (Wsig, Buf'Address, 1, + Flags => SOSC.MSG_Forced_Flags, + To => System.Null_Address, + Tolen => 0); + end Write; + +end Signalling_Fds; -- cgit v1.2.3