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_remote_port(struct stream *, ovs_be16 remote_port);
44 void stream_set_local_ip(struct stream *, ovs_be32 local_ip);
45 void stream_set_local_port(struct stream *, ovs_be16 local_port);
46 static inline void stream_assert_class(const struct stream *stream,
47 const struct stream_class *class)
49 assert(stream->class == class);
53 /* Prefix for connection names, e.g. "tcp", "ssl", "unix". */
56 /* True if this stream needs periodic probes to verify connectivity. For
57 * streams which need probes, it can take a long time to notice the
58 * connection was dropped. */
61 /* Attempts to connect to a peer. 'name' is the full connection name
62 * provided by the user, e.g. "tcp:1.2.3.4". This name is useful for error
63 * messages but must not be modified.
65 * 'suffix' is a copy of 'name' following the colon and may be modified.
66 * 'dscp' is the DSCP value that the new connection should use in the IP
69 * Returns 0 if successful, otherwise a positive errno value. If
70 * successful, stores a pointer to the new connection in '*streamp'.
72 * The open function must not block waiting for a connection to complete.
73 * If the connection cannot be completed immediately, it should return
74 * EAGAIN (not EINPROGRESS, as returned by the connect system call) and
75 * continue the connection in the background. */
76 int (*open)(const char *name, char *suffix, struct stream **streamp,
79 /* Closes 'stream' and frees associated memory. */
80 void (*close)(struct stream *stream);
82 /* Tries to complete the connection on 'stream'. If 'stream''s connection
83 * is complete, returns 0 if the connection was successful or a positive
84 * errno value if it failed. If the connection is still in progress,
87 * The connect function must not block waiting for the connection to
88 * complete; instead, it should return EAGAIN immediately. */
89 int (*connect)(struct stream *stream);
91 /* Tries to receive up to 'n' bytes from 'stream' into 'buffer', and
94 * - If successful, the number of bytes received (between 1 and 'n').
96 * - On error, a negative errno value.
98 * - 0, if the connection has been closed in the normal fashion.
100 * The recv function will not be passed a zero 'n'.
102 * The recv function must not block waiting for data to arrive. If no data
103 * have been received, it should return -EAGAIN immediately. */
104 ssize_t (*recv)(struct stream *stream, void *buffer, size_t n);
106 /* Tries to send up to 'n' bytes of 'buffer' on 'stream', and returns:
108 * - If successful, the number of bytes sent (between 1 and 'n').
110 * - On error, a negative errno value.
114 * The send function will not be passed a zero 'n'.
116 * The send function must not block. If no bytes can be immediately
117 * accepted for transmission, it should return -EAGAIN immediately. */
118 ssize_t (*send)(struct stream *stream, const void *buffer, size_t n);
120 /* Allows 'stream' to perform maintenance activities, such as flushing
123 * May be null if 'stream' doesn't have anything to do here. */
124 void (*run)(struct stream *stream);
126 /* Arranges for the poll loop to wake up when 'stream' needs to perform
127 * maintenance activities.
129 * May be null if 'stream' doesn't have anything to do here. */
130 void (*run_wait)(struct stream *stream);
132 /* Arranges for the poll loop to wake up when 'stream' is ready to take an
133 * action of the given 'type'. */
134 void (*wait)(struct stream *stream, enum stream_wait_type type);
137 /* Passive listener for incoming stream connections.
139 * This structure should be treated as opaque by stream implementations. */
141 const struct pstream_class *class;
145 void pstream_init(struct pstream *, const struct pstream_class *, const char *name);
146 static inline void pstream_assert_class(const struct pstream *pstream,
147 const struct pstream_class *class)
149 assert(pstream->class == class);
152 struct pstream_class {
153 /* Prefix for connection names, e.g. "ptcp", "pssl", "punix". */
156 /* True if this pstream needs periodic probes to verify connectivity. For
157 * pstreams which need probes, it can take a long time to notice the
158 * connection was dropped. */
161 /* Attempts to start listening for stream connections. 'name' is the full
162 * connection name provided by the user, e.g. "ptcp:1234". This name is
163 * useful for error messages but must not be modified.
165 * 'suffix' is a copy of 'name' following the colon and may be modified.
166 * 'dscp' is the DSCP value that the new connection should use in the IP
169 * Returns 0 if successful, otherwise a positive errno value. If
170 * successful, stores a pointer to the new connection in '*pstreamp'.
172 * The listen function must not block. If the connection cannot be
173 * completed immediately, it should return EAGAIN (not EINPROGRESS, as
174 * returned by the connect system call) and continue the connection in the
176 int (*listen)(const char *name, char *suffix, struct pstream **pstreamp,
179 /* Closes 'pstream' and frees associated memory. */
180 void (*close)(struct pstream *pstream);
182 /* Tries to accept a new connection on 'pstream'. If successful, stores
183 * the new connection in '*new_streamp' and returns 0. Otherwise, returns
184 * a positive errno value.
186 * The accept function must not block waiting for a connection. If no
187 * connection is ready to be accepted, it should return EAGAIN. */
188 int (*accept)(struct pstream *pstream, struct stream **new_streamp);
190 /* Arranges for the poll loop to wake up when a connection is ready to be
191 * accepted on 'pstream'. */
192 void (*wait)(struct pstream *pstream);
194 /* Set DSCP value of the listening socket. */
195 int (*set_dscp)(struct pstream *pstream, uint8_t dscp);
198 /* Active and passive stream classes. */
199 extern const struct stream_class tcp_stream_class;
200 extern const struct pstream_class ptcp_pstream_class;
201 extern const struct stream_class unix_stream_class;
202 extern const struct pstream_class punix_pstream_class;
204 extern const struct stream_class ssl_stream_class;
205 extern const struct pstream_class pssl_pstream_class;
208 #endif /* stream-provider.h */