1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- G N A T . S O C K E T S . T H I N --
9 -- Copyright (C) 2001-2004 Ada Core Technologies, Inc. --
11 -- GNAT is free software; you can redistribute it and/or modify it under --
12 -- terms of the GNU General Public License as published by the Free Soft- --
13 -- ware Foundation; either version 2, or (at your option) any later ver- --
14 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
15 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
16 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
17 -- for more details. You should have received a copy of the GNU General --
18 -- Public License distributed with GNAT; see file COPYING. If not, write --
19 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
20 -- MA 02111-1307, USA. --
22 -- As a special exception, if other files instantiate generics from this --
23 -- unit, or you link this unit with other files to produce an executable, --
24 -- this unit does not by itself cause the resulting executable to be --
25 -- covered by the GNU General Public License. This exception does not --
26 -- however invalidate any other reasons why the executable file might be --
27 -- covered by the GNU Public License. --
29 -- GNAT was originally developed by the GNAT team at New York University. --
30 -- Extensive contributions were provided by Ada Core Technologies Inc. --
32 ------------------------------------------------------------------------------
34 -- This package provides a target dependent thin interface to the sockets
35 -- layer for use by the GNAT.Sockets package (g-socket.ads). This package
36 -- should not be directly with'ed by an applications program.
38 -- This is the default version
40 with GNAT.OS_Lib; use GNAT.OS_Lib;
43 with Interfaces.C; use Interfaces.C;
45 package body GNAT.Sockets.Thin is
47 Non_Blocking_Sockets : constant Fd_Set_Access :=
48 New_Socket_Set (No_Socket_Set);
49 -- When this package is initialized with Process_Blocking_IO set
50 -- to True, sockets are set in non-blocking mode to avoid blocking
51 -- the whole process when a thread wants to perform a blocking IO
52 -- operation. But the user can also set a socket in non-blocking
53 -- mode by purpose. In order to make a difference between these
54 -- two situations, we track the origin of non-blocking mode in
55 -- Non_Blocking_Sockets. If S is in Non_Blocking_Sockets, it has
56 -- been set in non-blocking mode by the user.
58 Quantum : constant Duration := 0.2;
59 -- When Thread_Blocking_IO is False, we set sockets in
60 -- non-blocking mode and we spend a period of time Quantum between
61 -- two attempts on a blocking operation.
63 Thread_Blocking_IO : Boolean := True;
64 -- Comment required for this ???
66 Unknown_System_Error : constant C.Strings.chars_ptr :=
67 C.Strings.New_String ("Unknown system error");
69 -- Comments required for following functions ???
71 function Syscall_Accept
73 Addr : System.Address;
74 Addrlen : access C.int) return C.int;
75 pragma Import (C, Syscall_Accept, "accept");
77 function Syscall_Connect
79 Name : System.Address;
80 Namelen : C.int) return C.int;
81 pragma Import (C, Syscall_Connect, "connect");
83 function Syscall_Ioctl
86 Arg : Int_Access) return C.int;
87 pragma Import (C, Syscall_Ioctl, "ioctl");
93 Flags : C.int) return C.int;
94 pragma Import (C, Syscall_Recv, "recv");
96 function Syscall_Recvfrom
101 From : Sockaddr_In_Access;
102 Fromlen : access C.int) return C.int;
103 pragma Import (C, Syscall_Recvfrom, "recvfrom");
105 function Syscall_Send
107 Msg : System.Address;
109 Flags : C.int) return C.int;
110 pragma Import (C, Syscall_Send, "send");
112 function Syscall_Sendto
114 Msg : System.Address;
117 To : Sockaddr_In_Access;
118 Tolen : C.int) return C.int;
119 pragma Import (C, Syscall_Sendto, "sendto");
121 function Syscall_Socket
124 Protocol : C.int) return C.int;
125 pragma Import (C, Syscall_Socket, "socket");
127 procedure Disable_SIGPIPE (S : C.int);
128 pragma Import (C, Disable_SIGPIPE, "__gnat_disable_sigpipe");
130 function Non_Blocking_Socket (S : C.int) return Boolean;
131 procedure Set_Non_Blocking_Socket (S : C.int; V : Boolean);
139 Addr : System.Address;
140 Addrlen : access C.int) return C.int
143 Val : aliased C.int := 1;
146 pragma Warnings (Off, Discard);
150 R := Syscall_Accept (S, Addr, Addrlen);
151 exit when Thread_Blocking_IO
153 or else Non_Blocking_Socket (S)
154 or else Errno /= Constants.EWOULDBLOCK;
158 if not Thread_Blocking_IO
159 and then R /= Failure
161 -- A socket inherits the properties ot its server especially
162 -- the FIONBIO flag. Do not use C_Ioctl as this subprogram
163 -- tracks sockets set in non-blocking mode by user.
165 Set_Non_Blocking_Socket (R, Non_Blocking_Socket (S));
166 Discard := Syscall_Ioctl (R, Constants.FIONBIO, Val'Unchecked_Access);
179 Name : System.Address;
180 Namelen : C.int) return C.int
185 Res := Syscall_Connect (S, Name, Namelen);
187 if Thread_Blocking_IO
188 or else Res /= Failure
189 or else Non_Blocking_Socket (S)
190 or else Errno /= Constants.EINPROGRESS
196 WSet : Fd_Set_Access;
197 Now : aliased Timeval;
200 WSet := New_Socket_Set (No_Socket_Set);
202 Insert_Socket_In_Set (WSet, S);
209 Now'Unchecked_Access);
213 if Res = Failure then
214 Free_Socket_Set (WSet);
221 Free_Socket_Set (WSet);
224 Res := Syscall_Connect (S, Name, Namelen);
227 and then Errno = Constants.EISCONN
242 Arg : Int_Access) return C.int
245 if not Thread_Blocking_IO
246 and then Req = Constants.FIONBIO
249 Set_Non_Blocking_Socket (S, True);
253 return Syscall_Ioctl (S, Req, Arg);
262 Msg : System.Address;
264 Flags : C.int) return C.int
270 Res := Syscall_Recv (S, Msg, Len, Flags);
271 exit when Thread_Blocking_IO
272 or else Res /= Failure
273 or else Non_Blocking_Socket (S)
274 or else Errno /= Constants.EWOULDBLOCK;
287 Msg : System.Address;
290 From : Sockaddr_In_Access;
291 Fromlen : access C.int) return C.int
297 Res := Syscall_Recvfrom (S, Msg, Len, Flags, From, Fromlen);
298 exit when Thread_Blocking_IO
299 or else Res /= Failure
300 or else Non_Blocking_Socket (S)
301 or else Errno /= Constants.EWOULDBLOCK;
314 Msg : System.Address;
316 Flags : C.int) return C.int
322 Res := Syscall_Send (S, Msg, Len, Flags);
323 exit when Thread_Blocking_IO
324 or else Res /= Failure
325 or else Non_Blocking_Socket (S)
326 or else Errno /= Constants.EWOULDBLOCK;
339 Msg : System.Address;
342 To : Sockaddr_In_Access;
343 Tolen : C.int) return C.int
349 Res := Syscall_Sendto (S, Msg, Len, Flags, To, Tolen);
350 exit when Thread_Blocking_IO
351 or else Res /= Failure
352 or else Non_Blocking_Socket (S)
353 or else Errno /= Constants.EWOULDBLOCK;
367 Protocol : C.int) return C.int
370 Val : aliased C.int := 1;
373 pragma Unreferenced (Discard);
376 R := Syscall_Socket (Domain, Typ, Protocol);
378 if not Thread_Blocking_IO
379 and then R /= Failure
381 -- Do not use C_Ioctl as this subprogram tracks sockets set
382 -- in non-blocking mode by user.
384 Discard := Syscall_Ioctl (R, Constants.FIONBIO, Val'Unchecked_Access);
385 Set_Non_Blocking_Socket (R, False);
395 procedure Finalize is
404 procedure Initialize (Process_Blocking_IO : Boolean) is
406 Thread_Blocking_IO := not Process_Blocking_IO;
409 -------------------------
410 -- Non_Blocking_Socket --
411 -------------------------
413 function Non_Blocking_Socket (S : C.int) return Boolean is
417 R := (Is_Socket_In_Set (Non_Blocking_Sockets, S) /= 0);
420 end Non_Blocking_Socket;
426 procedure Set_Address
427 (Sin : Sockaddr_In_Access;
431 Sin.Sin_Addr := Address;
439 (Sin : Sockaddr_In_Access;
443 Sin.Sin_Family := C.unsigned_short (Family);
451 (Sin : Sockaddr_In_Access;
454 pragma Unreferenced (Sin);
455 pragma Unreferenced (Len);
461 -----------------------------
462 -- Set_Non_Blocking_Socket --
463 -----------------------------
465 procedure Set_Non_Blocking_Socket (S : C.int; V : Boolean) is
470 Insert_Socket_In_Set (Non_Blocking_Sockets, S);
472 Remove_Socket_From_Set (Non_Blocking_Sockets, S);
476 end Set_Non_Blocking_Socket;
483 (Sin : Sockaddr_In_Access;
484 Port : C.unsigned_short)
487 Sin.Sin_Port := Port;
490 --------------------------
491 -- Socket_Error_Message --
492 --------------------------
494 function Socket_Error_Message
495 (Errno : Integer) return C.Strings.chars_ptr
497 use type Interfaces.C.Strings.chars_ptr;
499 C_Msg : C.Strings.chars_ptr;
502 C_Msg := C_Strerror (C.int (Errno));
504 if C_Msg = C.Strings.Null_Ptr then
505 return Unknown_System_Error;
510 end Socket_Error_Message;
512 end GNAT.Sockets.Thin;