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git.proxmox.com Git - mirror_ovs.git/blob - lib/stream.c
2 * Copyright (c) 2008, 2009, 2010 Nicira Networks.
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.
18 #include "stream-provider.h"
22 #include <netinet/in.h>
27 #include "dynamic-string.h"
29 #include "ofp-print.h"
31 #include "openflow/nicira-ext.h"
32 #include "openflow/openflow.h"
34 #include "poll-loop.h"
38 #define THIS_MODULE VLM_stream
41 /* State of an active stream.*/
43 SCS_CONNECTING
, /* Underlying stream is not connected. */
44 SCS_CONNECTED
, /* Connection established. */
45 SCS_DISCONNECTED
/* Connection failed or connection closed. */
48 static struct stream_class
*stream_classes
[] = {
56 static struct pstream_class
*pstream_classes
[] = {
64 /* Check the validity of the stream class structures. */
66 check_stream_classes(void)
71 for (i
= 0; i
< ARRAY_SIZE(stream_classes
); i
++) {
72 struct stream_class
*class = stream_classes
[i
];
73 assert(class->name
!= NULL
);
74 assert(class->open
!= NULL
);
75 if (class->close
|| class->recv
|| class->send
|| class->run
76 || class->run_wait
|| class->wait
) {
77 assert(class->close
!= NULL
);
78 assert(class->recv
!= NULL
);
79 assert(class->send
!= NULL
);
80 assert(class->wait
!= NULL
);
82 /* This class delegates to another one. */
86 for (i
= 0; i
< ARRAY_SIZE(pstream_classes
); i
++) {
87 struct pstream_class
*class = pstream_classes
[i
];
88 assert(class->name
!= NULL
);
89 assert(class->listen
!= NULL
);
90 if (class->close
|| class->accept
|| class->wait
) {
91 assert(class->close
!= NULL
);
92 assert(class->accept
!= NULL
);
93 assert(class->wait
!= NULL
);
95 /* This class delegates to another one. */
101 /* Prints information on active (if 'active') and passive (if 'passive')
102 * connection methods supported by the stream. */
104 stream_usage(const char *name
, bool active
, bool passive
,
105 bool bootstrap UNUSED
)
107 /* Really this should be implemented via callbacks into the stream
108 * providers, but that seems too heavy-weight to bother with at the
113 printf("Active %s connection methods:\n", name
);
114 printf(" tcp:IP:PORT "
115 "PORT at remote IP\n");
117 printf(" ssl:IP:PORT "
118 "SSL PORT at remote IP\n");
121 "Unix domain socket named FILE\n");
125 printf("Passive %s connection methods:\n", name
);
126 printf(" ptcp:PORT[:IP] "
127 "listen to TCP PORT on IP\n");
129 printf(" pssl:PORT[:IP] "
130 "listen for SSL on PORT on IP\n");
132 printf(" punix:FILE "
133 "listen on Unix domain socket FILE\n");
137 printf("PKI configuration (required to use SSL):\n"
138 " -p, --private-key=FILE file with private key\n"
139 " -c, --certificate=FILE file with certificate for private key\n"
140 " -C, --ca-cert=FILE file with peer CA certificate\n");
142 printf(" --bootstrap-ca-cert=FILE file with peer CA certificate "
143 "to read or create\n");
148 /* Attempts to connect a stream to a remote peer. 'name' is a connection name
149 * in the form "TYPE:ARGS", where TYPE is an active stream class's name and
150 * ARGS are stream class-specific.
152 * Returns 0 if successful, otherwise a positive errno value. If successful,
153 * stores a pointer to the new connection in '*streamp', otherwise a null
156 stream_open(const char *name
, struct stream
**streamp
)
161 COVERAGE_INC(stream_open
);
162 check_stream_classes();
165 prefix_len
= strcspn(name
, ":");
166 if (prefix_len
== strlen(name
)) {
169 for (i
= 0; i
< ARRAY_SIZE(stream_classes
); i
++) {
170 struct stream_class
*class = stream_classes
[i
];
171 if (strlen(class->name
) == prefix_len
172 && !memcmp(class->name
, name
, prefix_len
)) {
173 struct stream
*stream
;
174 char *suffix_copy
= xstrdup(name
+ prefix_len
+ 1);
175 int retval
= class->open(name
, suffix_copy
, &stream
);
178 assert(stream
->state
!= SCS_CONNECTING
179 || stream
->class->connect
);
189 stream_open_block(const char *name
, struct stream
**streamp
)
191 struct stream
*stream
;
194 error
= stream_open(name
, &stream
);
195 while (error
== EAGAIN
) {
197 stream_run_wait(stream
);
198 stream_connect_wait(stream
);
200 error
= stream_connect(stream
);
201 assert(error
!= EINPROGRESS
);
204 stream_close(stream
);
212 /* Closes 'stream'. */
214 stream_close(struct stream
*stream
)
216 if (stream
!= NULL
) {
217 char *name
= stream
->name
;
218 (stream
->class->close
)(stream
);
223 /* Returns the name of 'stream', that is, the string passed to
226 stream_get_name(const struct stream
*stream
)
228 return stream
? stream
->name
: "(null)";
231 /* Returns the IP address of the peer, or 0 if the peer is not connected over
232 * an IP-based protocol or if its IP address is not yet known. */
234 stream_get_remote_ip(const struct stream
*stream
)
236 return stream
->remote_ip
;
239 /* Returns the transport port of the peer, or 0 if the connection does not
240 * contain a port or if the port is not yet known. */
242 stream_get_remote_port(const struct stream
*stream
)
244 return stream
->remote_port
;
247 /* Returns the IP address used to connect to the peer, or 0 if the connection
248 * is not an IP-based protocol or if its IP address is not yet known. */
250 stream_get_local_ip(const struct stream
*stream
)
252 return stream
->local_ip
;
255 /* Returns the transport port used to connect to the peer, or 0 if the
256 * connection does not contain a port or if the port is not yet known. */
258 stream_get_local_port(const struct stream
*stream
)
260 return stream
->local_port
;
264 scs_connecting(struct stream
*stream
)
266 int retval
= (stream
->class->connect
)(stream
);
267 assert(retval
!= EINPROGRESS
);
269 stream
->state
= SCS_CONNECTED
;
270 } else if (retval
!= EAGAIN
) {
271 stream
->state
= SCS_DISCONNECTED
;
272 stream
->error
= retval
;
276 /* Tries to complete the connection on 'stream', which must be an active
277 * stream. If 'stream''s connection is complete, returns 0 if the connection
278 * was successful or a positive errno value if it failed. If the
279 * connection is still in progress, returns EAGAIN. */
281 stream_connect(struct stream
*stream
)
283 enum stream_state last_state
;
286 last_state
= stream
->state
;
287 switch (stream
->state
) {
289 scs_connecting(stream
);
295 case SCS_DISCONNECTED
:
296 return stream
->error
;
301 } while (stream
->state
!= last_state
);
306 /* Tries to receive up to 'n' bytes from 'stream' into 'buffer', and returns:
308 * - If successful, the number of bytes received (between 1 and 'n').
310 * - On error, a negative errno value.
312 * - 0, if the connection has been closed in the normal fashion, or if 'n'
315 * The recv function will not block waiting for a packet to arrive. If no
316 * data have been received, it returns -EAGAIN immediately. */
318 stream_recv(struct stream
*stream
, void *buffer
, size_t n
)
320 int retval
= stream_connect(stream
);
321 return (retval
? -retval
323 : (stream
->class->recv
)(stream
, buffer
, n
));
326 /* Tries to send up to 'n' bytes of 'buffer' on 'stream', and returns:
328 * - If successful, the number of bytes sent (between 1 and 'n'). 0 is
329 * only a valid return value if 'n' is 0.
331 * - On error, a negative errno value.
333 * The send function will not block. If no bytes can be immediately accepted
334 * for transmission, it returns -EAGAIN immediately. */
336 stream_send(struct stream
*stream
, const void *buffer
, size_t n
)
338 int retval
= stream_connect(stream
);
339 return (retval
? -retval
341 : (stream
->class->send
)(stream
, buffer
, n
));
344 /* Allows 'stream' to perform maintenance activities, such as flushing
347 stream_run(struct stream
*stream
)
349 if (stream
->class->run
) {
350 (stream
->class->run
)(stream
);
354 /* Arranges for the poll loop to wake up when 'stream' needs to perform
355 * maintenance activities. */
357 stream_run_wait(struct stream
*stream
)
359 if (stream
->class->run_wait
) {
360 (stream
->class->run_wait
)(stream
);
364 /* Arranges for the poll loop to wake up when 'stream' is ready to take an
365 * action of the given 'type'. */
367 stream_wait(struct stream
*stream
, enum stream_wait_type wait
)
369 assert(wait
== STREAM_CONNECT
|| wait
== STREAM_RECV
370 || wait
== STREAM_SEND
);
372 switch (stream
->state
) {
374 wait
= STREAM_CONNECT
;
377 case SCS_DISCONNECTED
:
378 poll_immediate_wake();
381 (stream
->class->wait
)(stream
, wait
);
385 stream_connect_wait(struct stream
*stream
)
387 stream_wait(stream
, STREAM_CONNECT
);
391 stream_recv_wait(struct stream
*stream
)
393 stream_wait(stream
, STREAM_RECV
);
397 stream_send_wait(struct stream
*stream
)
399 stream_wait(stream
, STREAM_SEND
);
402 /* Attempts to start listening for remote stream connections. 'name' is a
403 * connection name in the form "TYPE:ARGS", where TYPE is an passive stream
404 * class's name and ARGS are stream class-specific.
406 * Returns 0 if successful, otherwise a positive errno value. If successful,
407 * stores a pointer to the new connection in '*pstreamp', otherwise a null
410 pstream_open(const char *name
, struct pstream
**pstreamp
)
415 check_stream_classes();
418 prefix_len
= strcspn(name
, ":");
419 if (prefix_len
== strlen(name
)) {
422 for (i
= 0; i
< ARRAY_SIZE(pstream_classes
); i
++) {
423 struct pstream_class
*class = pstream_classes
[i
];
424 if (strlen(class->name
) == prefix_len
425 && !memcmp(class->name
, name
, prefix_len
)) {
426 char *suffix_copy
= xstrdup(name
+ prefix_len
+ 1);
427 int retval
= class->listen(name
, suffix_copy
, pstreamp
);
438 /* Returns the name that was used to open 'pstream'. The caller must not
439 * modify or free the name. */
441 pstream_get_name(const struct pstream
*pstream
)
443 return pstream
->name
;
446 /* Closes 'pstream'. */
448 pstream_close(struct pstream
*pstream
)
450 if (pstream
!= NULL
) {
451 char *name
= pstream
->name
;
452 (pstream
->class->close
)(pstream
);
457 /* Tries to accept a new connection on 'pstream'. If successful, stores the
458 * new connection in '*new_stream' and returns 0. Otherwise, returns a
459 * positive errno value.
461 * pstream_accept() will not block waiting for a connection. If no connection
462 * is ready to be accepted, it returns EAGAIN immediately. */
464 pstream_accept(struct pstream
*pstream
, struct stream
**new_stream
)
466 int retval
= (pstream
->class->accept
)(pstream
, new_stream
);
470 assert((*new_stream
)->state
!= SCS_CONNECTING
471 || (*new_stream
)->class->connect
);
476 /* Tries to accept a new connection on 'pstream'. If successful, stores the
477 * new connection in '*new_stream' and returns 0. Otherwise, returns a
478 * positive errno value.
480 * pstream_accept_block() blocks until a connection is ready or until an error
481 * occurs. It will not return EAGAIN. */
483 pstream_accept_block(struct pstream
*pstream
, struct stream
**new_stream
)
487 while ((error
= pstream_accept(pstream
, new_stream
)) == EAGAIN
) {
488 pstream_wait(pstream
);
498 pstream_wait(struct pstream
*pstream
)
500 (pstream
->class->wait
)(pstream
);
503 /* Initializes 'stream' as a new stream named 'name', implemented via 'class'.
504 * The initial connection status, supplied as 'connect_status', is interpreted
507 * - 0: 'stream' is connected. Its 'send' and 'recv' functions may be
508 * called in the normal fashion.
510 * - EAGAIN: 'stream' is trying to complete a connection. Its 'connect'
511 * function should be called to complete the connection.
513 * - Other positive errno values indicate that the connection failed with
514 * the specified error.
516 * After calling this function, stream_close() must be used to destroy
517 * 'stream', otherwise resources will be leaked.
519 * The caller retains ownership of 'name'. */
521 stream_init(struct stream
*stream
, struct stream_class
*class,
522 int connect_status
, const char *name
)
524 stream
->class = class;
525 stream
->state
= (connect_status
== EAGAIN
? SCS_CONNECTING
526 : !connect_status
? SCS_CONNECTED
528 stream
->error
= connect_status
;
529 stream
->name
= xstrdup(name
);
530 assert(stream
->state
!= SCS_CONNECTING
|| class->connect
);
534 stream_set_remote_ip(struct stream
*stream
, uint32_t ip
)
536 stream
->remote_ip
= ip
;
540 stream_set_remote_port(struct stream
*stream
, uint16_t port
)
542 stream
->remote_port
= port
;
546 stream_set_local_ip(struct stream
*stream
, uint32_t ip
)
548 stream
->local_ip
= ip
;
552 stream_set_local_port(struct stream
*stream
, uint16_t port
)
554 stream
->local_port
= port
;
558 pstream_init(struct pstream
*pstream
, struct pstream_class
*class,
561 pstream
->class = class;
562 pstream
->name
= xstrdup(name
);