1 /* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements. See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License. You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
18 * @file http_connection.h
19 * @brief Apache connection library
21 * @defgroup APACHE_CORE_CONNECTION Connection Library
22 * @ingroup APACHE_CORE
26 #ifndef APACHE_HTTP_CONNECTION_H
27 #define APACHE_HTTP_CONNECTION_H
29 #include "apr_network_io.h"
30 #include "apr_buckets.h"
37 * This is the protocol module driver. This calls all of the
38 * pre-connection and connection hooks for all protocol modules.
39 * @param c The connection on which the request is read
40 * @param csd The mechanism on which this connection is to be read.
41 * Most times this will be a socket, but it is up to the module
42 * that accepts the request to determine the exact type.
44 AP_CORE_DECLARE(void) ap_process_connection(conn_rec *c, void *csd);
47 * Shutdown the connection for writing.
48 * @param c The connection to shutdown
49 * @param flush Whether or not to flush pending data before
50 * @return APR_SUCCESS or the underlying error
52 AP_CORE_DECLARE(apr_status_t) ap_shutdown_conn(conn_rec *c, int flush);
55 * Flushes all remain data in the client send buffer
56 * @param c The connection to flush
57 * @remark calls ap_shutdown_conn(c, 1)
59 AP_CORE_DECLARE(void) ap_flush_conn(conn_rec *c);
62 * This function is responsible for the following cases:
64 * we now proceed to read from the client until we get EOF, or until
65 * MAX_SECS_TO_LINGER has passed. The reasons for doing this are
66 * documented in a draft:
68 * http://tools.ietf.org/html/draft-ietf-http-connection-00.txt
70 * in a nutshell -- if we don't make this effort we risk causing
71 * TCP RST packets to be sent which can tear down a connection before
72 * all the response data has been sent to the client.
74 * @param c The connection we are closing
76 AP_DECLARE(void) ap_lingering_close(conn_rec *c);
78 AP_DECLARE(int) ap_prep_lingering_close(conn_rec *c);
80 AP_DECLARE(int) ap_start_lingering_close(conn_rec *c);
84 * create_connection is a RUN_FIRST hook which allows modules to create
85 * connections. In general, you should not install filters with the
86 * create_connection hook. If you require vhost configuration information
87 * to make filter installation decisions, you must use the pre_connection
88 * or install_network_transport hook. This hook should close the connection
89 * if it encounters a fatal error condition.
91 * @param p The pool from which to allocate the connection record
92 * @param server The server record to create the connection too.
93 * @param csd The socket that has been accepted
94 * @param conn_id A unique identifier for this connection. The ID only
95 * needs to be unique at that time, not forever.
96 * @param sbh A handle to scoreboard information for this connection.
97 * @param alloc The bucket allocator to use for all bucket/brigade creations
98 * @return An allocated connection record or NULL.
100 AP_DECLARE_HOOK(conn_rec *, create_connection,
101 (apr_pool_t *p, server_rec *server, apr_socket_t *csd,
102 long conn_id, void *sbh, apr_bucket_alloc_t *alloc))
105 * This hook gives protocol modules an opportunity to set everything up
106 * before calling the protocol handler. All pre-connection hooks are
107 * run until one returns something other than ok or decline
108 * @param c The connection on which the request has been received.
109 * @param csd The mechanism on which this connection is to be read.
110 * Most times this will be a socket, but it is up to the module
111 * that accepts the request to determine the exact type.
112 * @return OK or DECLINED
114 AP_DECLARE_HOOK(int,pre_connection,(conn_rec *c, void *csd))
117 * This hook implements different protocols. After a connection has been
118 * established, the protocol module must read and serve the request. This
119 * function does that for each protocol module. The first protocol module
120 * to handle the request is the last module run.
121 * @param c The connection on which the request has been received.
122 * @return OK or DECLINED
124 AP_DECLARE_HOOK(int,process_connection,(conn_rec *c))
127 * This hook implements different protocols. Before a connection is closed,
128 * protocols might have to perform some housekeeping actions, such as
129 * sending one last goodbye packet. The connection is, unless some other
130 * error already happened before, still open and operational.
131 * All pre-close-connection hooks are run until one returns something
132 * other than ok or decline
133 * @param c The connection on which the request has been received.
134 * @return OK or DECLINED
136 AP_DECLARE_HOOK(int,pre_close_connection,(conn_rec *c))
138 /** End Of Connection (EOC) bucket */
139 AP_DECLARE_DATA extern const apr_bucket_type_t ap_bucket_type_eoc;
142 * Determine if a bucket is an End Of Connection (EOC) bucket
143 * @param e The bucket to inspect
144 * @return true or false
146 #define AP_BUCKET_IS_EOC(e) (e->type == &ap_bucket_type_eoc)
149 * Make the bucket passed in an End Of Connection (EOC) bucket
150 * @param b The bucket to make into an EOC bucket
151 * @return The new bucket, or NULL if allocation failed
153 AP_DECLARE(apr_bucket *) ap_bucket_eoc_make(apr_bucket *b);
156 * Create a bucket referring to an End Of Connection (EOC). This indicates
157 * that the connection will be closed.
158 * @param list The freelist from which this bucket should be allocated
159 * @return The new bucket, or NULL if allocation failed
161 AP_DECLARE(apr_bucket *) ap_bucket_eoc_create(apr_bucket_alloc_t *list);
167 #endif /* !APACHE_HTTP_CONNECTION_H */