2 * Copyright (c) 2009, 2010 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
21 #include <sys/types.h>
24 /* Active stream connection. */
26 /* Active stream connection.
28 * This structure should be treated as opaque by implementation. */
30 const struct stream_class *class;
40 void stream_init(struct stream *, const struct stream_class *,
41 int connect_status, const char *name);
42 void stream_set_remote_ip(struct stream *, ovs_be32 remote_ip);
43 void stream_set_dscp(struct stream *, uint8_t dscp);
44 void stream_set_remote_port(struct stream *, ovs_be16 remote_port);
45 void stream_set_local_ip(struct stream *, ovs_be32 local_ip);
46 void stream_set_local_port(struct stream *, ovs_be16 local_port);
47 static inline void stream_assert_class(const struct stream *stream,
48 const struct stream_class *class)
50 assert(stream->class == class);
54 /* Prefix for connection names, e.g. "tcp", "ssl", "unix". */
57 /* True if this stream needs periodic probes to verify connectivity. For
58 * streams which need probes, it can take a long time to notice the
59 * connection was dropped. */
62 /* Attempts to connect to a peer. 'name' is the full connection name
63 * provided by the user, e.g. "tcp:1.2.3.4". This name is useful for error
64 * messages but must not be modified.
66 * 'suffix' is a copy of 'name' following the colon and may be modified.
67 * 'dscp' is the DSCP value that the new connection should use in the IP
70 * Returns 0 if successful, otherwise a positive errno value. If
71 * successful, stores a pointer to the new connection in '*streamp'.
73 * The open function must not block waiting for a connection to complete.
74 * If the connection cannot be completed immediately, it should return
75 * EAGAIN (not EINPROGRESS, as returned by the connect system call) and
76 * continue the connection in the background. */
77 int (*open)(const char *name, char *suffix, struct stream **streamp,
80 /* Closes 'stream' and frees associated memory. */
81 void (*close)(struct stream *stream);
83 /* Tries to complete the connection on 'stream'. If 'stream''s connection
84 * is complete, returns 0 if the connection was successful or a positive
85 * errno value if it failed. If the connection is still in progress,
88 * The connect function must not block waiting for the connection to
89 * complete; instead, it should return EAGAIN immediately. */
90 int (*connect)(struct stream *stream);
92 /* Tries to receive up to 'n' bytes from 'stream' into 'buffer', and
95 * - If successful, the number of bytes received (between 1 and 'n').
97 * - On error, a negative errno value.
99 * - 0, if the connection has been closed in the normal fashion.
101 * The recv function will not be passed a zero 'n'.
103 * The recv function must not block waiting for data to arrive. If no data
104 * have been received, it should return -EAGAIN immediately. */
105 ssize_t (*recv)(struct stream *stream, void *buffer, size_t n);
107 /* Tries to send up to 'n' bytes of 'buffer' on 'stream', and returns:
109 * - If successful, the number of bytes sent (between 1 and 'n').
111 * - On error, a negative errno value.
115 * The send function will not be passed a zero 'n'.
117 * The send function must not block. If no bytes can be immediately
118 * accepted for transmission, it should return -EAGAIN immediately. */
119 ssize_t (*send)(struct stream *stream, const void *buffer, size_t n);
121 /* Allows 'stream' to perform maintenance activities, such as flushing
124 * May be null if 'stream' doesn't have anything to do here. */
125 void (*run)(struct stream *stream);
127 /* Arranges for the poll loop to wake up when 'stream' needs to perform
128 * maintenance activities.
130 * May be null if 'stream' doesn't have anything to do here. */
131 void (*run_wait)(struct stream *stream);
133 /* Arranges for the poll loop to wake up when 'stream' is ready to take an
134 * action of the given 'type'. */
135 void (*wait)(struct stream *stream, enum stream_wait_type type);
138 /* Passive listener for incoming stream connections.
140 * This structure should be treated as opaque by stream implementations. */
142 const struct pstream_class *class;
146 void pstream_init(struct pstream *, const struct pstream_class *, const char *name);
147 static inline void pstream_assert_class(const struct pstream *pstream,
148 const struct pstream_class *class)
150 assert(pstream->class == class);
153 struct pstream_class {
154 /* Prefix for connection names, e.g. "ptcp", "pssl", "punix". */
157 /* True if this pstream needs periodic probes to verify connectivity. For
158 * pstreams which need probes, it can take a long time to notice the
159 * connection was dropped. */
162 /* Attempts to start listening for stream connections. 'name' is the full
163 * connection name provided by the user, e.g. "ptcp:1234". This name is
164 * useful for error messages but must not be modified.
166 * 'suffix' is a copy of 'name' following the colon and may be modified.
167 * 'dscp' is the DSCP value that the new connection should use in the IP
170 * Returns 0 if successful, otherwise a positive errno value. If
171 * successful, stores a pointer to the new connection in '*pstreamp'.
173 * The listen function must not block. If the connection cannot be
174 * completed immediately, it should return EAGAIN (not EINPROGRESS, as
175 * returned by the connect system call) and continue the connection in the
177 int (*listen)(const char *name, char *suffix, struct pstream **pstreamp,
180 /* Closes 'pstream' and frees associated memory. */
181 void (*close)(struct pstream *pstream);
183 /* Tries to accept a new connection on 'pstream'. If successful, stores
184 * the new connection in '*new_streamp' and returns 0. Otherwise, returns
185 * a positive errno value.
187 * The accept function must not block waiting for a connection. If no
188 * connection is ready to be accepted, it should return EAGAIN. */
189 int (*accept)(struct pstream *pstream, struct stream **new_streamp);
191 /* Arranges for the poll loop to wake up when a connection is ready to be
192 * accepted on 'pstream'. */
193 void (*wait)(struct pstream *pstream);
196 /* Active and passive stream classes. */
197 extern const struct stream_class tcp_stream_class;
198 extern const struct pstream_class ptcp_pstream_class;
199 extern const struct stream_class unix_stream_class;
200 extern const struct pstream_class punix_pstream_class;
202 extern const struct stream_class ssl_stream_class;
203 extern const struct pstream_class pssl_pstream_class;
206 #endif /* stream-provider.h */