1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- G N A T . S O C K E T S . T H I N --
10 -- Copyright (C) 2001 Ada Core Technologies, Inc. --
12 -- GNAT is free software; you can redistribute it and/or modify it under --
13 -- terms of the GNU General Public License as published by the Free Soft- --
14 -- ware Foundation; either version 2, or (at your option) any later ver- --
15 -- sion. GNAT is distributed in the hope that it will be useful, but WITH- --
16 -- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY --
17 -- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License --
18 -- for more details. You should have received a copy of the GNU General --
19 -- Public License distributed with GNAT; see file COPYING. If not, write --
20 -- to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, --
21 -- MA 02111-1307, USA. --
23 -- As a special exception, if other files instantiate generics from this --
24 -- unit, or you link this unit with other files to produce an executable, --
25 -- this unit does not by itself cause the resulting executable to be --
26 -- covered by the GNU General Public License. This exception does not --
27 -- however invalidate any other reasons why the executable file might be --
28 -- covered by the GNU Public License. --
30 -- GNAT is maintained by Ada Core Technologies Inc (http://www.gnat.com). --
32 ------------------------------------------------------------------------------
34 with GNAT.OS_Lib; use GNAT.OS_Lib;
36 with Interfaces.C; use Interfaces.C;
38 package body GNAT.Sockets.Thin is
40 -- When this package is initialized with Process_Blocking_IO set
41 -- to True, sockets are set in non-blocking mode to avoid blocking
42 -- the whole process when a thread wants to perform a blocking IO
43 -- operation. But the user can set a socket in non-blocking mode
44 -- by purpose. We track the socket in such a mode by redefining
45 -- C_Ioctl. In blocking IO operations, we exit normally when the
46 -- non-blocking flag is set by user, we poll and try later when
47 -- this flag is set automatically by this package.
49 type Socket_Info is record
50 Non_Blocking : Boolean := False;
53 Table : array (C.int range 0 .. 31) of Socket_Info;
54 -- Get info on blocking flag. This array is limited to 32 sockets
55 -- because the select operation allows socket set of less then 32
58 Quantum : constant Duration := 0.2;
61 Thread_Blocking_IO : Boolean := True;
63 function Syscall_Accept
65 Addr : System.Address;
66 Addrlen : access C.int)
68 pragma Import (C, Syscall_Accept, "accept");
70 function Syscall_Connect
72 Name : System.Address;
75 pragma Import (C, Syscall_Connect, "connect");
77 function Syscall_Ioctl
82 pragma Import (C, Syscall_Ioctl, "ioctl");
90 pragma Import (C, Syscall_Recv, "recv");
92 function Syscall_Recvfrom
97 From : Sockaddr_In_Access;
98 Fromlen : access C.int)
100 pragma Import (C, Syscall_Recvfrom, "recvfrom");
102 function Syscall_Send
104 Msg : System.Address;
108 pragma Import (C, Syscall_Send, "send");
110 function Syscall_Sendto
112 Msg : System.Address;
115 To : Sockaddr_In_Access;
118 pragma Import (C, Syscall_Sendto, "sendto");
120 function Syscall_Socket
121 (Domain, Typ, Protocol : C.int)
123 pragma Import (C, Syscall_Socket, "socket");
125 procedure Set_Non_Blocking (S : C.int);
133 Addr : System.Address;
134 Addrlen : access C.int)
141 Res := Syscall_Accept (S, Addr, Addrlen);
142 exit when Thread_Blocking_IO
143 or else Res /= Failure
144 or else Table (S).Non_Blocking
145 or else Errno /= Constants.EWOULDBLOCK;
149 if not Thread_Blocking_IO
150 and then Res /= Failure
152 -- A socket inherits the properties ot its server especially
155 Table (Res).Non_Blocking := Table (S).Non_Blocking;
156 Set_Non_Blocking (Res);
168 Name : System.Address;
175 Res := Syscall_Connect (S, Name, Namelen);
177 if Thread_Blocking_IO
178 or else Res /= Failure
179 or else Table (S).Non_Blocking
180 or else Errno /= Constants.EINPROGRESS
186 Set : aliased Fd_Set;
187 Now : aliased Timeval;
191 Set := 2 ** Natural (S);
195 null, Set'Unchecked_Access,
196 null, Now'Unchecked_Access);
200 if Res = Failure then
208 Res := Syscall_Connect (S, Name, Namelen);
211 and then Errno = Constants.EISCONN
230 if not Thread_Blocking_IO
231 and then Req = Constants.FIONBIO
233 Table (S).Non_Blocking := (Arg.all /= 0);
236 return Syscall_Ioctl (S, Req, Arg);
245 Msg : System.Address;
254 Res := Syscall_Recv (S, Msg, Len, Flags);
255 exit when Thread_Blocking_IO
256 or else Res /= Failure
257 or else Table (S).Non_Blocking
258 or else Errno /= Constants.EWOULDBLOCK;
271 Msg : System.Address;
274 From : Sockaddr_In_Access;
275 Fromlen : access C.int)
282 Res := Syscall_Recvfrom (S, Msg, Len, Flags, From, Fromlen);
283 exit when Thread_Blocking_IO
284 or else Res /= Failure
285 or else Table (S).Non_Blocking
286 or else Errno /= Constants.EWOULDBLOCK;
299 Msg : System.Address;
308 Res := Syscall_Send (S, Msg, Len, Flags);
309 exit when Thread_Blocking_IO
310 or else Res /= Failure
311 or else Table (S).Non_Blocking
312 or else Errno /= Constants.EWOULDBLOCK;
325 Msg : System.Address;
328 To : Sockaddr_In_Access;
336 Res := Syscall_Sendto (S, Msg, Len, Flags, To, Tolen);
337 exit when Thread_Blocking_IO
338 or else Res /= Failure
339 or else Table (S).Non_Blocking
340 or else Errno /= Constants.EWOULDBLOCK;
360 Res := Syscall_Socket (Domain, Typ, Protocol);
362 if not Thread_Blocking_IO
363 and then Res /= Failure
365 Set_Non_Blocking (Res);
376 (Item : in out Fd_Set;
379 Mask : constant Fd_Set := 2 ** Natural (Socket);
382 if (Item and Mask) /= 0 then
383 Item := Item xor Mask;
391 procedure Empty (Item : in out Fd_Set) is
400 procedure Finalize is
409 procedure Initialize (Process_Blocking_IO : Boolean) is
411 Thread_Blocking_IO := not Process_Blocking_IO;
418 function Is_Empty (Item : Fd_Set) return Boolean is
427 function Is_Set (Item : Fd_Set; Socket : C.int) return Boolean is
429 return (Item and 2 ** Natural (Socket)) /= 0;
436 function Max (Item : Fd_Set) return C.int
453 procedure Set (Item : in out Fd_Set; Socket : in C.int) is
455 Item := Item or 2 ** Natural (Socket);
458 ----------------------
459 -- Set_Non_Blocking --
460 ----------------------
462 procedure Set_Non_Blocking (S : C.int) is
464 Val : aliased C.int := 1;
468 -- Do not use C_Fcntl because this subprogram tracks the
469 -- sockets set by user in non-blocking mode.
471 Res := Syscall_Ioctl (S, Constants.FIONBIO, Val'Unchecked_Access);
472 end Set_Non_Blocking;
474 --------------------------
475 -- Socket_Error_Message --
476 --------------------------
478 function Socket_Error_Message (Errno : Integer) return String is
479 use type Interfaces.C.Strings.chars_ptr;
481 C_Msg : C.Strings.chars_ptr;
484 C_Msg := C_Strerror (C.int (Errno));
486 if C_Msg = C.Strings.Null_Ptr then
487 return "Unknown system error";
490 return C.Strings.Value (C_Msg);
492 end Socket_Error_Message;
494 end GNAT.Sockets.Thin;