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/* ====================================================================
* Copyright (c) 1995-1999 The Apache Group. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the Apache Group
* for use in the Apache HTTP server project (http://www.apache.org/)."
*
* 4. The names "Apache Server" and "Apache Group" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the Apache Group
* for use in the Apache HTTP server project (http://www.apache.org/)."
*
* THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE GROUP OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Group and was originally based
* on public domain software written at the National Center for
* Supercomputing Applications, University of Illinois, Urbana-Champaign.
* For more information on the Apache Group and the Apache HTTP server
* project, please see <http://www.apache.org/>.
*
*/
#define CORE_PRIVATE
#include "httpd.h"
#include "http_connection.h"
#include "http_request.h"
#include "http_protocol.h"
#include "ap_mpm.h"
#include "http_config.h"
#include "http_vhost.h"
#include <poll.h>
/*
* More machine-dependent networking gooo... on some systems,
* you've got to be *really* sure that all the packets are acknowledged
* before closing the connection, since the client will not be able
* to see the last response if their TCP buffer is flushed by a RST
* packet from us, which is what the server's TCP stack will send
* if it receives any request data after closing the connection.
*
* In an ideal world, this function would be accomplished by simply
* setting the socket option SO_LINGER and handling it within the
* server's TCP stack while the process continues on to the next request.
* Unfortunately, it seems that most (if not all) operating systems
* block the server process on close() when SO_LINGER is used.
* For those that don't, see USE_SO_LINGER below. For the rest,
* we have created a home-brew lingering_close.
*
* Many operating systems tend to block, puke, or otherwise mishandle
* calls to shutdown only half of the connection. You should define
* NO_LINGCLOSE in ap_config.h if such is the case for your system.
*/
#ifndef MAX_SECS_TO_LINGER
#define MAX_SECS_TO_LINGER 30
#endif
#ifdef USE_SO_LINGER
#define NO_LINGCLOSE /* The two lingering options are exclusive */
static void sock_enable_linger(int s) // ZZZZZ abstract the socket, s
{
struct linger li; // ZZZZZ SocketOptions...
li.l_onoff = 1;
li.l_linger = MAX_SECS_TO_LINGER;
if (setsockopt(s, SOL_SOCKET, SO_LINGER, // ZZZZZ abstract, return SUCCESS or not
(char *) &li, sizeof(struct linger)) < 0) {
ap_log_error(APLOG_MARK, APLOG_WARNING, server_conf,
"setsockopt: (SO_LINGER)");
/* not a fatal error */
}
}
#else
#define sock_enable_linger(s) /* NOOP */
#endif /* USE_SO_LINGER */
#ifndef NO_LINGCLOSE
/* Since many clients will abort a connection instead of closing it,
* attempting to log an error message from this routine will only
* confuse the webmaster. There doesn't seem to be any portable way to
* distinguish between a dropped connection and something that might be
* worth logging.
*/
/*ZZZ this routine needs to be adapted for use with poll()*/
static void lingering_close(request_rec *r)
{
/*ZZZ remove the hardwired 512. This is an IO Buffer Size */
char dummybuf[512];
struct pollfd pd;
int lsd;
int max_wait;
/* Prevent a slow-drip client from holding us here indefinitely */
max_wait = 30;
ap_bsetopt(r->connection->client, BO_TIMEOUT, &max_wait);
/* Send any leftover data to the client, but never try to again */
if (ap_bflush(r->connection->client) == -1) {
ap_bclose(r->connection->client);
return;
}
ap_bsetflag(r->connection->client, B_EOUT, 1);
/* Close our half of the connection --- send the client a FIN */
lsd = r->connection->client->fd;
if ((shutdown(lsd, 1) != 0) /* ZZZ abstract shutdown */
|| ap_is_aborted(r->connection)) {
ap_bclose(r->connection->client);
return;
}
/* Set up to wait for readable data on socket... */
pd.fd = lsd;
pd.events = POLLIN;
/* Wait for readable data or error condition on socket;
* slurp up any data that arrives... We exit when we go for an
* interval of tv length without getting any more data, get an error
* from poll(), get an error or EOF on a read, or the timer expires.
*/
/* We use a 2 second timeout because current (Feb 97) browsers
* fail to close a connection after the server closes it. Thus,
* to avoid keeping the child busy, we are only lingering long enough
* for a client that is actively sending data on a connection.
* This should be sufficient unless the connection is massively
* losing packets, in which case we might have missed the RST anyway.
* These parameters are reset on each pass, since they might be
* changed by poll.
*/
do {
pd.revents = 0;
} while ((poll(&pd, 1, 2) == 1)
&& read(lsd, dummybuf, sizeof(dummybuf)));
/* && (time() = epoch) < max_wait); */ /* ZZZZ time function is not good... */
/* Should now have seen final ack. Safe to finally kill socket */
ap_bclose(r->connection->client);
}
#endif /* ndef NO_LINGCLOSE */
CORE_EXPORT(void) ap_process_connection(conn_rec *c)
{
request_rec *r;
ap_update_vhost_given_ip(c);
/*
* Read and process each request found on our connection
* until no requests are left or we decide to close.
*/
while ((r = ap_read_request(c)) != NULL) {
/* process the request if it was read without error */
if (r->status == HTTP_OK)
ap_process_request(r);
if (!c->keepalive || c->aborted)
break;
ap_destroy_pool(r->pool);
if (ap_mpm_graceful_stop()) {
/* XXX: hey wait, this should do a lingering_close! */
ap_bclose(c->client);
return;
}
}
/*
* Close the connection, being careful to send out whatever is still
* in our buffers. If possible, try to avoid a hard close until the
* client has ACKed our FIN and/or has stopped sending us data.
*/
#ifdef NO_LINGCLOSE
ap_bclose(c->client); /* just close it */
#else
if (r && r->connection
&& !r->connection->aborted
&& r->connection->client
&& (r->connection->client->fd >= 0)) {
lingering_close(r);
}
else {
ap_bsetflag(c->client, B_EOUT, 1);
ap_bclose(c->client);
}
#endif
}
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