1 /* Copyright 1999-2004 Apache Software Foundation
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
7 * http://www.apache.org/licenses/LICENSE-2.0
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
17 #include "apr_strings.h"
20 #include "ap_config.h"
22 #include "http_connection.h"
23 #include "http_request.h"
24 #include "http_protocol.h"
26 #include "mpm_default.h"
27 #include "http_config.h"
28 #include "http_core.h"
29 #include "http_vhost.h"
30 #include "scoreboard.h"
32 #include "util_filter.h"
35 APR_HOOK_LINK(create_connection)
36 APR_HOOK_LINK(process_connection)
37 APR_HOOK_LINK(pre_connection)
39 AP_IMPLEMENT_HOOK_RUN_FIRST(conn_rec *,create_connection,
40 (apr_pool_t *p, server_rec *server, apr_socket_t *csd, long conn_id, void *sbh, apr_bucket_alloc_t *alloc),
41 (p, server, csd, conn_id, sbh, alloc), NULL)
42 AP_IMPLEMENT_HOOK_RUN_FIRST(int,process_connection,(conn_rec *c),(c),DECLINED)
43 AP_IMPLEMENT_HOOK_RUN_ALL(int,pre_connection,(conn_rec *c, void *csd),(c, csd),OK,DECLINED)
45 * More machine-dependent networking gooo... on some systems,
46 * you've got to be *really* sure that all the packets are acknowledged
47 * before closing the connection, since the client will not be able
48 * to see the last response if their TCP buffer is flushed by a RST
49 * packet from us, which is what the server's TCP stack will send
50 * if it receives any request data after closing the connection.
52 * In an ideal world, this function would be accomplished by simply
53 * setting the socket option SO_LINGER and handling it within the
54 * server's TCP stack while the process continues on to the next request.
55 * Unfortunately, it seems that most (if not all) operating systems
56 * block the server process on close() when SO_LINGER is used.
57 * For those that don't, see USE_SO_LINGER below. For the rest,
58 * we have created a home-brew lingering_close.
60 * Many operating systems tend to block, puke, or otherwise mishandle
61 * calls to shutdown only half of the connection. You should define
62 * NO_LINGCLOSE in ap_config.h if such is the case for your system.
64 #ifndef MAX_SECS_TO_LINGER
65 #define MAX_SECS_TO_LINGER 30
68 AP_CORE_DECLARE(void) ap_flush_conn(conn_rec *c)
70 apr_bucket_brigade *bb;
73 bb = apr_brigade_create(c->pool, c->bucket_alloc);
74 b = apr_bucket_flush_create(c->bucket_alloc);
75 APR_BRIGADE_INSERT_TAIL(bb, b);
76 ap_pass_brigade(c->output_filters, bb);
79 /* we now proceed to read from the client until we get EOF, or until
80 * MAX_SECS_TO_LINGER has passed. the reasons for doing this are
81 * documented in a draft:
83 * http://www.ics.uci.edu/pub/ietf/http/draft-ietf-http-connection-00.txt
85 * in a nutshell -- if we don't make this effort we risk causing
86 * TCP RST packets to be sent which can tear down a connection before
87 * all the response data has been sent to the client.
89 #define SECONDS_TO_LINGER 2
90 AP_DECLARE(void) ap_lingering_close(conn_rec *c)
93 apr_size_t nbytes = sizeof(dummybuf);
96 apr_int32_t total_linger_time = 0;
97 apr_socket_t *csd = ap_get_module_config(c->conn_config, &core_module);
103 ap_update_child_status(c->sbh, SERVER_CLOSING, NULL);
106 ap_flush_conn(c); /* just close it */
107 apr_socket_close(csd);
111 /* Close the connection, being careful to send out whatever is still
112 * in our buffers. If possible, try to avoid a hard close until the
113 * client has ACKed our FIN and/or has stopped sending us data.
116 /* Send any leftover data to the client, but never try to again */
120 apr_socket_close(csd);
124 /* Shut down the socket for write, which will send a FIN
127 if (apr_socket_shutdown(csd, APR_SHUTDOWN_WRITE) != APR_SUCCESS
129 apr_socket_close(csd);
133 /* Read all data from the peer until we reach "end-of-file" (FIN
134 * from peer) or we've exceeded our overall timeout. If the client does
135 * not send us bytes within 2 seconds (a value pulled from Apache 1.3
136 * which seems to work well), close the connection.
138 timeout = apr_time_from_sec(SECONDS_TO_LINGER);
139 apr_socket_timeout_set(csd, timeout);
140 apr_socket_opt_set(csd, APR_INCOMPLETE_READ, 1);
142 nbytes = sizeof(dummybuf);
143 rc = apr_socket_recv(csd, dummybuf, &nbytes);
144 if (rc != APR_SUCCESS || nbytes == 0)
147 total_linger_time += SECONDS_TO_LINGER;
148 if (total_linger_time >= MAX_SECS_TO_LINGER) {
153 apr_socket_close(csd);
157 AP_CORE_DECLARE(void) ap_process_connection(conn_rec *c, void *csd)
160 ap_update_vhost_given_ip(c);
162 rc = ap_run_pre_connection(c, csd);
163 if (rc != OK && rc != DONE) {
168 ap_run_process_connection(c);