Date: Tue, 2 Jul 2013 10:23:46 +0100 From: David Chisnall <theraven@FreeBSD.org> To: Ambarisha B <b.ambarisha@gmail.com> Cc: soc-status@FreeBSD.org Subject: Re: IDMS : Weekly status report #2 of 14 Message-ID: <C2E395F2-3026-48E1-8A62-E9BC36F0DFBD@FreeBSD.org> In-Reply-To: <CAJP25sPv9FvWjm0125ix0iDm18nZfAFO_O-0MWz6PZ=UdwypKw@mail.gmail.com> References: <CAJP25sPv9FvWjm0125ix0iDm18nZfAFO_O-0MWz6PZ=UdwypKw@mail.gmail.com>
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On 1 Jul 2013, at 19:27, Ambarisha B <b.ambarisha@gmail.com> wrote:
> 3. Refactor the client to give an open fd to the server (instead of
> expecting one, as is the model with libfetch)
Can you explain a bit what this means? The daemon should be the thing =
openning the connection. The forked worker should then pass it to =
libfetch. The code in the daemon should look something approximately =
like this:
struct client_request req;
int IPC_connection_to_clients =3D /* whatever you're using here, most =
likely a UNIX domain socket so that you can pass in the fd for the =
output file from the client. */;
while (wait_for_request(IPC_connection_to_clients, &req) {
/* URL parsing code goes here. */
int fd server =3D connect(...);
/* Error handling goes here */
/* You may want to create a pipe here for sending progress =
messages from the client back to the server */
/* You may want to queue requests and not start downloading =
immediately if some bandwidth or number of concurrent downloads quota is =
reached */
/* Create the worker */
pid_t child =3D fork();
/* Error handling here */
if (child =3D=3D 0)
{
/* Now we're in the worker, close any file descriptors =
that we shouldn't have */
close(IPC_connection_to_clients);
close(stdin);
close(stdout);
/* Then enter sandboxed mode */
cap_enter();
/* Now do the real downloading and exit */
do_the_real_downloading(server, req.output_file, =
req.url);
exit(0);
}
else
{
/* Close the file descriptors that the worker is using. =
*/
close(server);
close(req.output_file);
/* Probably add child to a list of things that you'll =
wait for exit signals from in the kqueue call in the wait_for_request =
part */
}
}
David
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