2 * Copyright (c) 2009, 2010, 2012 Nicira, Inc.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * 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.
17 #ifndef STREAM_PROVIDER_H
18 #define STREAM_PROVIDER_H 1
20 #include <sys/types.h>
23 /* Active stream connection. */
25 /* Active stream connection.
27 * This structure should be treated as opaque by implementation. */
29 const struct stream_class *class;
39 void stream_init(struct stream *, const struct stream_class *,
40 int connect_status, const char *name);
41 void stream_set_remote_ip(struct stream *, ovs_be32 remote_ip);
42 void stream_set_remote_port(struct stream *, ovs_be16 remote_port);
43 void stream_set_local_ip(struct stream *, ovs_be32 local_ip);
44 void stream_set_local_port(struct stream *, ovs_be16 local_port);
45 static inline void stream_assert_class(const struct stream *stream,
46 const struct stream_class *class)
48 ovs_assert(stream->class == class);
52 /* Prefix for connection names, e.g. "tcp", "ssl", "unix". */
55 /* True if this stream needs periodic probes to verify connectivity. For
56 * streams which need probes, it can take a long time to notice the
57 * connection was dropped. */
60 /* Attempts to connect to a peer. 'name' is the full connection name
61 * provided by the user, e.g. "tcp:1.2.3.4". This name is useful for error
62 * messages but must not be modified.
64 * 'suffix' is a copy of 'name' following the colon and may be modified.
65 * 'dscp' is the DSCP value that the new connection should use in the IP
68 * Returns 0 if successful, otherwise a positive errno value. If
69 * successful, stores a pointer to the new connection in '*streamp'.
71 * The open function must not block waiting for a connection to complete.
72 * If the connection cannot be completed immediately, it should return
73 * EAGAIN (not EINPROGRESS, as returned by the connect system call) and
74 * continue the connection in the background. */
75 int (*open)(const char *name, char *suffix, struct stream **streamp,
78 /* Closes 'stream' and frees associated memory. */
79 void (*close)(struct stream *stream);
81 /* Tries to complete the connection on 'stream'. If 'stream''s connection
82 * is complete, returns 0 if the connection was successful or a positive
83 * errno value if it failed. If the connection is still in progress,
86 * The connect function must not block waiting for the connection to
87 * complete; instead, it should return EAGAIN immediately. */
88 int (*connect)(struct stream *stream);
90 /* Tries to receive up to 'n' bytes from 'stream' into 'buffer', and
93 * - If successful, the number of bytes received (between 1 and 'n').
95 * - On error, a negative errno value.
97 * - 0, if the connection has been closed in the normal fashion.
99 * The recv function will not be passed a zero 'n'.
101 * The recv function must not block waiting for data to arrive. If no data
102 * have been received, it should return -EAGAIN immediately. */
103 ssize_t (*recv)(struct stream *stream, void *buffer, size_t n);
105 /* Tries to send up to 'n' bytes of 'buffer' on 'stream', and returns:
107 * - If successful, the number of bytes sent (between 1 and 'n').
109 * - On error, a negative errno value.
113 * The send function will not be passed a zero 'n'.
115 * The send function must not block. If no bytes can be immediately
116 * accepted for transmission, it should return -EAGAIN immediately. */
117 ssize_t (*send)(struct stream *stream, const void *buffer, size_t n);
119 /* Allows 'stream' to perform maintenance activities, such as flushing
122 * May be null if 'stream' doesn't have anything to do here. */
123 void (*run)(struct stream *stream);
125 /* Arranges for the poll loop to wake up when 'stream' needs to perform
126 * maintenance activities.
128 * May be null if 'stream' doesn't have anything to do here. */
129 void (*run_wait)(struct stream *stream);
131 /* Arranges for the poll loop to wake up when 'stream' is ready to take an
132 * action of the given 'type'. */
133 void (*wait)(struct stream *stream, enum stream_wait_type type);
136 /* Passive listener for incoming stream connections.
138 * This structure should be treated as opaque by stream implementations. */
140 const struct pstream_class *class;
144 void pstream_init(struct pstream *, const struct pstream_class *, const char *name);
145 static inline void pstream_assert_class(const struct pstream *pstream,
146 const struct pstream_class *class)
148 ovs_assert(pstream->class == class);
151 struct pstream_class {
152 /* Prefix for connection names, e.g. "ptcp", "pssl", "punix". */
155 /* True if this pstream needs periodic probes to verify connectivity. For
156 * pstreams which need probes, it can take a long time to notice the
157 * connection was dropped. */
160 /* Attempts to start listening for stream connections. 'name' is the full
161 * connection name provided by the user, e.g. "ptcp:1234". This name is
162 * useful for error messages but must not be modified.
164 * 'suffix' is a copy of 'name' following the colon and may be modified.
165 * 'dscp' is the DSCP value that the new connection should use in the IP
168 * Returns 0 if successful, otherwise a positive errno value. If
169 * successful, stores a pointer to the new connection in '*pstreamp'.
171 * The listen function must not block. If the connection cannot be
172 * completed immediately, it should return EAGAIN (not EINPROGRESS, as
173 * returned by the connect system call) and continue the connection in the
175 int (*listen)(const char *name, char *suffix, struct pstream **pstreamp,
178 /* Closes 'pstream' and frees associated memory. */
179 void (*close)(struct pstream *pstream);
181 /* Tries to accept a new connection on 'pstream'. If successful, stores
182 * the new connection in '*new_streamp' and returns 0. Otherwise, returns
183 * a positive errno value.
185 * The accept function must not block waiting for a connection. If no
186 * connection is ready to be accepted, it should return EAGAIN. */
187 int (*accept)(struct pstream *pstream, struct stream **new_streamp);
189 /* Arranges for the poll loop to wake up when a connection is ready to be
190 * accepted on 'pstream'. */
191 void (*wait)(struct pstream *pstream);
193 /* Set DSCP value of the listening socket. */
194 int (*set_dscp)(struct pstream *pstream, uint8_t dscp);
197 /* Active and passive stream classes. */
198 extern const struct stream_class tcp_stream_class;
199 extern const struct pstream_class ptcp_pstream_class;
200 extern const struct stream_class unix_stream_class;
201 extern const struct pstream_class punix_pstream_class;
203 extern const struct stream_class ssl_stream_class;
204 extern const struct pstream_class pssl_pstream_class;
207 #endif /* stream-provider.h */