1 ------------------------------------------------------------------------------
3 -- GNAT COMPILER COMPONENTS --
5 -- G N A T . S O C K E T S . T H I N --
9 -- Copyright (C) 2001-2006, AdaCore --
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, 51 Franklin Street, Fifth Floor, --
20 -- Boston, MA 02110-1301, 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 : not null 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 : not null 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 procedure Disable_All_SIGPIPEs;
131 pragma Import (C, Disable_All_SIGPIPEs, "__gnat_disable_all_sigpipes");
132 -- Sets the process to ignore all SIGPIPE signals on platforms that
133 -- don't support Disable_SIGPIPE for particular streams.
135 function Non_Blocking_Socket (S : C.int) return Boolean;
136 procedure Set_Non_Blocking_Socket (S : C.int; V : Boolean);
144 Addr : System.Address;
145 Addrlen : not null access C.int) return C.int
148 Val : aliased C.int := 1;
151 pragma Warnings (Off, Discard);
155 R := Syscall_Accept (S, Addr, Addrlen);
156 exit when Thread_Blocking_IO
158 or else Non_Blocking_Socket (S)
159 or else Errno /= Constants.EWOULDBLOCK;
163 if not Thread_Blocking_IO
164 and then R /= Failure
166 -- A socket inherits the properties ot its server especially
167 -- the FIONBIO flag. Do not use C_Ioctl as this subprogram
168 -- tracks sockets set in non-blocking mode by user.
170 Set_Non_Blocking_Socket (R, Non_Blocking_Socket (S));
171 Discard := Syscall_Ioctl (R, Constants.FIONBIO, Val'Unchecked_Access);
184 Name : System.Address;
185 Namelen : C.int) return C.int
190 Res := Syscall_Connect (S, Name, Namelen);
192 if Thread_Blocking_IO
193 or else Res /= Failure
194 or else Non_Blocking_Socket (S)
195 or else Errno /= Constants.EINPROGRESS
201 WSet : Fd_Set_Access;
202 Now : aliased Timeval;
205 WSet := New_Socket_Set (No_Socket_Set);
207 Insert_Socket_In_Set (WSet, S);
214 Now'Unchecked_Access);
218 if Res = Failure then
219 Free_Socket_Set (WSet);
226 Free_Socket_Set (WSet);
229 Res := Syscall_Connect (S, Name, Namelen);
232 and then Errno = Constants.EISCONN
247 Arg : Int_Access) return C.int
250 if not Thread_Blocking_IO
251 and then Req = Constants.FIONBIO
254 Set_Non_Blocking_Socket (S, True);
258 return Syscall_Ioctl (S, Req, Arg);
267 Msg : System.Address;
269 Flags : C.int) return C.int
275 Res := Syscall_Recv (S, Msg, Len, Flags);
276 exit when Thread_Blocking_IO
277 or else Res /= Failure
278 or else Non_Blocking_Socket (S)
279 or else Errno /= Constants.EWOULDBLOCK;
292 Msg : System.Address;
295 From : Sockaddr_In_Access;
296 Fromlen : not null access C.int) return C.int
302 Res := Syscall_Recvfrom (S, Msg, Len, Flags, From, Fromlen);
303 exit when Thread_Blocking_IO
304 or else Res /= Failure
305 or else Non_Blocking_Socket (S)
306 or else Errno /= Constants.EWOULDBLOCK;
319 Msg : System.Address;
321 Flags : C.int) return C.int
327 Res := Syscall_Send (S, Msg, Len, Flags);
328 exit when Thread_Blocking_IO
329 or else Res /= Failure
330 or else Non_Blocking_Socket (S)
331 or else Errno /= Constants.EWOULDBLOCK;
344 Msg : System.Address;
347 To : Sockaddr_In_Access;
348 Tolen : C.int) return C.int
354 Res := Syscall_Sendto (S, Msg, Len, Flags, To, Tolen);
355 exit when Thread_Blocking_IO
356 or else Res /= Failure
357 or else Non_Blocking_Socket (S)
358 or else Errno /= Constants.EWOULDBLOCK;
372 Protocol : C.int) return C.int
375 Val : aliased C.int := 1;
378 pragma Unreferenced (Discard);
381 R := Syscall_Socket (Domain, Typ, Protocol);
383 if not Thread_Blocking_IO
384 and then R /= Failure
386 -- Do not use C_Ioctl as this subprogram tracks sockets set
387 -- in non-blocking mode by user.
389 Discard := Syscall_Ioctl (R, Constants.FIONBIO, Val'Unchecked_Access);
390 Set_Non_Blocking_Socket (R, False);
400 procedure Finalize is
409 procedure Initialize (Process_Blocking_IO : Boolean) is
411 Thread_Blocking_IO := not Process_Blocking_IO;
412 Disable_All_SIGPIPEs;
415 -------------------------
416 -- Non_Blocking_Socket --
417 -------------------------
419 function Non_Blocking_Socket (S : C.int) return Boolean is
423 R := (Is_Socket_In_Set (Non_Blocking_Sockets, S) /= 0);
426 end Non_Blocking_Socket;
432 procedure Set_Address
433 (Sin : Sockaddr_In_Access;
437 Sin.Sin_Addr := Address;
445 (Sin : Sockaddr_In_Access;
449 Sin.Sin_Family := C.unsigned_short (Family);
457 (Sin : Sockaddr_In_Access;
460 pragma Unreferenced (Sin);
461 pragma Unreferenced (Len);
467 -----------------------------
468 -- Set_Non_Blocking_Socket --
469 -----------------------------
471 procedure Set_Non_Blocking_Socket (S : C.int; V : Boolean) is
476 Insert_Socket_In_Set (Non_Blocking_Sockets, S);
478 Remove_Socket_From_Set (Non_Blocking_Sockets, S);
482 end Set_Non_Blocking_Socket;
489 (Sin : Sockaddr_In_Access;
490 Port : C.unsigned_short)
493 Sin.Sin_Port := Port;
500 package body Signalling_Fds is
502 -- In this default implementation, we use a C version of these
503 -- subprograms provided by socket.c.
505 function C_Create (Fds : not null access Fd_Pair) return C.int;
506 function C_Read (Rsig : C.int) return C.int;
507 function C_Write (Wsig : C.int) return C.int;
509 pragma Import (C, C_Create, "__gnat_create_signalling_fds");
510 pragma Import (C, C_Read, "__gnat_read_signalling_fd");
511 pragma Import (C, C_Write, "__gnat_write_signalling_fd");
513 function Create (Fds : not null access Fd_Pair) return C.int
516 function Read (Rsig : C.int) return C.int renames C_Read;
518 function Write (Wsig : C.int) return C.int renames C_Write;
522 --------------------------
523 -- Socket_Error_Message --
524 --------------------------
526 function Socket_Error_Message
527 (Errno : Integer) return C.Strings.chars_ptr
529 use type Interfaces.C.Strings.chars_ptr;
531 C_Msg : C.Strings.chars_ptr;
534 C_Msg := C_Strerror (C.int (Errno));
536 if C_Msg = C.Strings.Null_Ptr then
537 return Unknown_System_Error;
541 end Socket_Error_Message;
543 end GNAT.Sockets.Thin;