2 * Copyright (c) 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 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.
24 #include "openvswitch/dynamic-string.h"
25 #include "fatal-signal.h"
26 #include "openvswitch/json.h"
27 #include "openvswitch/list.h"
28 #include "openvswitch/ofpbuf.h"
29 #include "ovs-thread.h"
30 #include "poll-loop.h"
31 #include "reconnect.h"
34 #include "openvswitch/vlog.h"
36 VLOG_DEFINE_THIS_MODULE(jsonrpc
);
39 struct stream
*stream
;
45 uint8_t input_buffer
[512];
46 struct json_parser
*parser
;
49 struct ovs_list output
; /* Contains "struct ofpbuf"s. */
50 size_t output_count
; /* Number of elements in "output". */
54 /* Rate limit for error messages. */
55 static struct vlog_rate_limit rl
= VLOG_RATE_LIMIT_INIT(5, 5);
57 static struct jsonrpc_msg
*jsonrpc_parse_received_message(struct jsonrpc
*);
58 static void jsonrpc_cleanup(struct jsonrpc
*);
59 static void jsonrpc_error(struct jsonrpc
*, int error
);
61 /* This is just the same as stream_open() except that it uses the default
62 * JSONRPC port if none is specified. */
64 jsonrpc_stream_open(const char *name
, struct stream
**streamp
, uint8_t dscp
)
66 return stream_open_with_default_port(name
, OVSDB_PORT
, streamp
, dscp
);
69 /* This is just the same as pstream_open() except that it uses the default
70 * JSONRPC port if none is specified. */
72 jsonrpc_pstream_open(const char *name
, struct pstream
**pstreamp
, uint8_t dscp
)
74 return pstream_open_with_default_port(name
, OVSDB_PORT
, pstreamp
, dscp
);
77 /* Returns a new JSON-RPC stream that uses 'stream' for input and output. The
78 * new jsonrpc object takes ownership of 'stream'. */
80 jsonrpc_open(struct stream
*stream
)
84 ovs_assert(stream
!= NULL
);
86 rpc
= xzalloc(sizeof *rpc
);
87 rpc
->name
= xstrdup(stream_get_name(stream
));
89 byteq_init(&rpc
->input
, rpc
->input_buffer
, sizeof rpc
->input_buffer
);
90 ovs_list_init(&rpc
->output
);
95 /* Destroys 'rpc', closing the stream on which it is based, and frees its
98 jsonrpc_close(struct jsonrpc
*rpc
)
101 jsonrpc_cleanup(rpc
);
107 /* Performs periodic maintenance on 'rpc', such as flushing output buffers. */
109 jsonrpc_run(struct jsonrpc
*rpc
)
115 stream_run(rpc
->stream
);
116 while (!ovs_list_is_empty(&rpc
->output
)) {
117 struct ofpbuf
*buf
= ofpbuf_from_list(rpc
->output
.next
);
120 retval
= stream_send(rpc
->stream
, buf
->data
, buf
->size
);
122 rpc
->backlog
-= retval
;
123 ofpbuf_pull(buf
, retval
);
125 ovs_list_remove(&buf
->list_node
);
130 if (retval
!= -EAGAIN
) {
131 VLOG_WARN_RL(&rl
, "%s: send error: %s",
132 rpc
->name
, ovs_strerror(-retval
));
133 jsonrpc_error(rpc
, -retval
);
140 /* Arranges for the poll loop to wake up when 'rpc' needs to perform
141 * maintenance activities. */
143 jsonrpc_wait(struct jsonrpc
*rpc
)
146 stream_run_wait(rpc
->stream
);
147 if (!ovs_list_is_empty(&rpc
->output
)) {
148 stream_send_wait(rpc
->stream
);
154 * Returns the current status of 'rpc'. The possible return values are:
157 * - EOF: end of file (remote end closed connection; not necessarily an error).
159 * When this function returns nonzero, 'rpc' is effectively out of
160 * commission. 'rpc' will not receive any more messages and any further
161 * messages that one attempts to send with 'rpc' will be discarded. The
162 * caller can keep 'rpc' around as long as it wants, but it's not going
163 * to provide any more useful services.
166 jsonrpc_get_status(const struct jsonrpc
*rpc
)
171 /* Returns the number of bytes buffered by 'rpc' to be written to the
172 * underlying stream. Always returns 0 if 'rpc' has encountered an error or if
173 * the remote end closed the connection. */
175 jsonrpc_get_backlog(const struct jsonrpc
*rpc
)
177 return rpc
->status
? 0 : rpc
->backlog
;
180 /* Returns the number of bytes that have been received on 'rpc''s underlying
181 * stream. (The value wraps around if it exceeds UINT_MAX.) */
183 jsonrpc_get_received_bytes(const struct jsonrpc
*rpc
)
185 return rpc
->input
.head
;
188 /* Returns 'rpc''s name, that is, the name returned by stream_get_name() for
189 * the stream underlying 'rpc' when 'rpc' was created. */
191 jsonrpc_get_name(const struct jsonrpc
*rpc
)
197 jsonrpc_log_msg(const struct jsonrpc
*rpc
, const char *title
,
198 const struct jsonrpc_msg
*msg
)
200 if (VLOG_IS_DBG_ENABLED()) {
201 struct ds s
= DS_EMPTY_INITIALIZER
;
203 ds_put_format(&s
, ", method=\"%s\"", msg
->method
);
206 ds_put_cstr(&s
, ", params=");
207 json_to_ds(msg
->params
, 0, &s
);
210 ds_put_cstr(&s
, ", result=");
211 json_to_ds(msg
->result
, 0, &s
);
214 ds_put_cstr(&s
, ", error=");
215 json_to_ds(msg
->error
, 0, &s
);
218 ds_put_cstr(&s
, ", id=");
219 json_to_ds(msg
->id
, 0, &s
);
221 VLOG_DBG("%s: %s %s%s", rpc
->name
, title
,
222 jsonrpc_msg_type_to_string(msg
->type
), ds_cstr(&s
));
227 /* Schedules 'msg' to be sent on 'rpc' and returns 'rpc''s status (as with
228 * jsonrpc_get_status()).
230 * If 'msg' cannot be sent immediately, it is appended to a buffer. The caller
231 * is responsible for ensuring that the amount of buffered data is somehow
232 * limited. (jsonrpc_get_backlog() returns the amount of data currently
233 * buffered in 'rpc'.)
235 * Always takes ownership of 'msg', regardless of success. */
237 jsonrpc_send(struct jsonrpc
*rpc
, struct jsonrpc_msg
*msg
)
241 struct ds ds
= DS_EMPTY_INITIALIZER
;
245 jsonrpc_msg_destroy(msg
);
249 jsonrpc_log_msg(rpc
, "send", msg
);
251 json
= jsonrpc_msg_to_json(msg
);
252 json_to_ds(json
, 0, &ds
);
256 buf
= xmalloc(sizeof *buf
);
257 ofpbuf_use_ds(buf
, &ds
);
258 ovs_list_push_back(&rpc
->output
, &buf
->list_node
);
260 rpc
->backlog
+= length
;
262 if (rpc
->output_count
>= 50) {
263 VLOG_INFO_RL(&rl
, "excessive sending backlog, jsonrpc: %s, num of"
264 " msgs: %"PRIuSIZE
", backlog: %"PRIuSIZE
".", rpc
->name
,
265 rpc
->output_count
, rpc
->backlog
);
268 if (rpc
->backlog
== length
) {
274 /* Attempts to receive a message from 'rpc'.
276 * If successful, stores the received message in '*msgp' and returns 0. The
277 * caller takes ownership of '*msgp' and must eventually destroy it with
278 * jsonrpc_msg_destroy().
280 * Otherwise, stores NULL in '*msgp' and returns one of the following:
282 * - EAGAIN: No message has been received.
284 * - EOF: The remote end closed the connection gracefully.
286 * - Otherwise an errno value that represents a JSON-RPC protocol violation
287 * or another error fatal to the connection. 'rpc' will not send or
288 * receive any more messages.
291 jsonrpc_recv(struct jsonrpc
*rpc
, struct jsonrpc_msg
**msgp
)
300 for (i
= 0; i
< 50; i
++) {
303 /* Fill our input buffer if it's empty. */
304 if (byteq_is_empty(&rpc
->input
)) {
308 chunk
= byteq_headroom(&rpc
->input
);
309 retval
= stream_recv(rpc
->stream
, byteq_head(&rpc
->input
), chunk
);
311 if (retval
== -EAGAIN
) {
314 VLOG_WARN_RL(&rl
, "%s: receive error: %s",
315 rpc
->name
, ovs_strerror(-retval
));
316 jsonrpc_error(rpc
, -retval
);
319 } else if (retval
== 0) {
320 jsonrpc_error(rpc
, EOF
);
323 byteq_advance_head(&rpc
->input
, retval
);
326 /* We have some input. Feed it into the JSON parser. */
328 rpc
->parser
= json_parser_create(0);
330 n
= byteq_tailroom(&rpc
->input
);
331 used
= json_parser_feed(rpc
->parser
,
332 (char *) byteq_tail(&rpc
->input
), n
);
333 byteq_advance_tail(&rpc
->input
, used
);
335 /* If we have complete JSON, attempt to parse it as JSON-RPC. */
336 if (json_parser_is_done(rpc
->parser
)) {
337 *msgp
= jsonrpc_parse_received_message(rpc
);
343 const struct byteq
*q
= &rpc
->input
;
344 if (q
->head
<= q
->size
) {
345 stream_report_content(q
->buffer
, q
->head
, STREAM_JSONRPC
,
346 &this_module
, rpc
->name
);
356 /* Causes the poll loop to wake up when jsonrpc_recv() may return a value other
359 jsonrpc_recv_wait(struct jsonrpc
*rpc
)
361 if (rpc
->status
|| !byteq_is_empty(&rpc
->input
)) {
362 poll_immediate_wake_at(rpc
->name
);
364 stream_recv_wait(rpc
->stream
);
368 /* Sends 'msg' on 'rpc' and waits for it to be successfully queued to the
369 * underlying stream. Returns 0 if 'msg' was sent successfully, otherwise a
370 * status value (see jsonrpc_get_status()).
372 * Always takes ownership of 'msg', regardless of success. */
374 jsonrpc_send_block(struct jsonrpc
*rpc
, struct jsonrpc_msg
*msg
)
380 error
= jsonrpc_send(rpc
, msg
);
387 if (ovs_list_is_empty(&rpc
->output
) || rpc
->status
) {
395 /* Waits for a message to be received on 'rpc'. Same semantics as
396 * jsonrpc_recv() except that EAGAIN will never be returned. */
398 jsonrpc_recv_block(struct jsonrpc
*rpc
, struct jsonrpc_msg
**msgp
)
401 int error
= jsonrpc_recv(rpc
, msgp
);
402 if (error
!= EAGAIN
) {
409 jsonrpc_recv_wait(rpc
);
414 /* Sends 'request' to 'rpc' then waits for a reply. The return value is 0 if
415 * successful, in which case '*replyp' is set to the reply, which the caller
416 * must eventually free with jsonrpc_msg_destroy(). Otherwise returns a status
417 * value (see jsonrpc_get_status()).
419 * Discards any message received on 'rpc' that is not a reply to 'request'
420 * (based on message id).
422 * Always takes ownership of 'request', regardless of success. */
424 jsonrpc_transact_block(struct jsonrpc
*rpc
, struct jsonrpc_msg
*request
,
425 struct jsonrpc_msg
**replyp
)
427 struct jsonrpc_msg
*reply
= NULL
;
431 id
= json_clone(request
->id
);
432 error
= jsonrpc_send_block(rpc
, request
);
435 error
= jsonrpc_recv_block(rpc
, &reply
);
439 if ((reply
->type
== JSONRPC_REPLY
|| reply
->type
== JSONRPC_ERROR
)
440 && json_equal(id
, reply
->id
)) {
443 jsonrpc_msg_destroy(reply
);
446 *replyp
= error
? NULL
: reply
;
451 /* Attempts to parse the content of 'rpc->parser' (which is complete JSON) as a
452 * JSON-RPC message. If successful, returns the JSON-RPC message. On failure,
453 * signals an error on 'rpc' with jsonrpc_error() and returns NULL. */
454 static struct jsonrpc_msg
*
455 jsonrpc_parse_received_message(struct jsonrpc
*rpc
)
457 struct jsonrpc_msg
*msg
;
461 json
= json_parser_finish(rpc
->parser
);
463 if (json
->type
== JSON_STRING
) {
464 VLOG_WARN_RL(&rl
, "%s: error parsing stream: %s",
465 rpc
->name
, json_string(json
));
466 jsonrpc_error(rpc
, EPROTO
);
471 error
= jsonrpc_msg_from_json(json
, &msg
);
473 VLOG_WARN_RL(&rl
, "%s: received bad JSON-RPC message: %s",
476 jsonrpc_error(rpc
, EPROTO
);
480 jsonrpc_log_msg(rpc
, "received", msg
);
485 jsonrpc_error(struct jsonrpc
*rpc
, int error
)
490 jsonrpc_cleanup(rpc
);
495 jsonrpc_cleanup(struct jsonrpc
*rpc
)
497 stream_close(rpc
->stream
);
500 json_parser_abort(rpc
->parser
);
503 ofpbuf_list_delete(&rpc
->output
);
505 rpc
->output_count
= 0;
508 static struct jsonrpc_msg
*
509 jsonrpc_create(enum jsonrpc_msg_type type
, const char *method
,
510 struct json
*params
, struct json
*result
, struct json
*error
,
513 struct jsonrpc_msg
*msg
= xmalloc(sizeof *msg
);
515 msg
->method
= nullable_xstrdup(method
);
516 msg
->params
= params
;
517 msg
->result
= result
;
524 jsonrpc_create_id(void)
526 static atomic_count next_id
= ATOMIC_COUNT_INIT(0);
529 id
= atomic_count_inc(&next_id
);
530 return json_integer_create(id
);
534 jsonrpc_create_request(const char *method
, struct json
*params
,
537 struct json
*id
= jsonrpc_create_id();
539 *idp
= json_clone(id
);
541 return jsonrpc_create(JSONRPC_REQUEST
, method
, params
, NULL
, NULL
, id
);
545 jsonrpc_create_notify(const char *method
, struct json
*params
)
547 return jsonrpc_create(JSONRPC_NOTIFY
, method
, params
, NULL
, NULL
, NULL
);
551 jsonrpc_create_reply(struct json
*result
, const struct json
*id
)
553 return jsonrpc_create(JSONRPC_REPLY
, NULL
, NULL
, result
, NULL
,
558 jsonrpc_create_error(struct json
*error
, const struct json
*id
)
560 return jsonrpc_create(JSONRPC_REPLY
, NULL
, NULL
, NULL
, error
,
565 jsonrpc_msg_type_to_string(enum jsonrpc_msg_type type
)
568 case JSONRPC_REQUEST
:
572 return "notification";
584 jsonrpc_msg_is_valid(const struct jsonrpc_msg
*m
)
586 const char *type_name
;
587 unsigned int pattern
;
589 if (m
->params
&& m
->params
->type
!= JSON_ARRAY
) {
590 return xstrdup("\"params\" must be JSON array");
594 case JSONRPC_REQUEST
:
611 return xasprintf("invalid JSON-RPC message type %d", m
->type
);
614 type_name
= jsonrpc_msg_type_to_string(m
->type
);
615 if ((m
->method
!= NULL
) != ((pattern
& 0x10000) != 0)) {
616 return xasprintf("%s must%s have \"method\"",
617 type_name
, (pattern
& 0x10000) ? "" : " not");
620 if ((m
->params
!= NULL
) != ((pattern
& 0x1000) != 0)) {
621 return xasprintf("%s must%s have \"params\"",
622 type_name
, (pattern
& 0x1000) ? "" : " not");
625 if ((m
->result
!= NULL
) != ((pattern
& 0x100) != 0)) {
626 return xasprintf("%s must%s have \"result\"",
627 type_name
, (pattern
& 0x100) ? "" : " not");
630 if ((m
->error
!= NULL
) != ((pattern
& 0x10) != 0)) {
631 return xasprintf("%s must%s have \"error\"",
632 type_name
, (pattern
& 0x10) ? "" : " not");
635 if ((m
->id
!= NULL
) != ((pattern
& 0x1) != 0)) {
636 return xasprintf("%s must%s have \"id\"",
637 type_name
, (pattern
& 0x1) ? "" : " not");
644 jsonrpc_msg_destroy(struct jsonrpc_msg
*m
)
648 json_destroy(m
->params
);
649 json_destroy(m
->result
);
650 json_destroy(m
->error
);
657 null_from_json_null(struct json
*json
)
659 if (json
&& json
->type
== JSON_NULL
) {
667 jsonrpc_msg_from_json(struct json
*json
, struct jsonrpc_msg
**msgp
)
669 struct json
*method
= NULL
;
670 struct jsonrpc_msg
*msg
= NULL
;
671 struct shash
*object
;
674 if (json
->type
!= JSON_OBJECT
) {
675 error
= xstrdup("message is not a JSON object");
678 object
= json_object(json
);
680 method
= shash_find_and_delete(object
, "method");
681 if (method
&& method
->type
!= JSON_STRING
) {
682 error
= xstrdup("method is not a JSON string");
686 msg
= xzalloc(sizeof *msg
);
687 msg
->method
= method
? xstrdup(method
->u
.string
) : NULL
;
688 msg
->params
= null_from_json_null(shash_find_and_delete(object
, "params"));
689 msg
->result
= null_from_json_null(shash_find_and_delete(object
, "result"));
690 msg
->error
= null_from_json_null(shash_find_and_delete(object
, "error"));
691 msg
->id
= null_from_json_null(shash_find_and_delete(object
, "id"));
692 msg
->type
= (msg
->result
? JSONRPC_REPLY
693 : msg
->error
? JSONRPC_ERROR
694 : msg
->id
? JSONRPC_REQUEST
696 if (!shash_is_empty(object
)) {
697 error
= xasprintf("message has unexpected member \"%s\"",
698 shash_first(object
)->name
);
701 error
= jsonrpc_msg_is_valid(msg
);
707 json_destroy(method
);
710 jsonrpc_msg_destroy(msg
);
718 jsonrpc_msg_to_json(struct jsonrpc_msg
*m
)
720 struct json
*json
= json_object_create();
723 json_object_put(json
, "method", json_string_create_nocopy(m
->method
));
727 json_object_put(json
, "params", m
->params
);
731 json_object_put(json
, "result", m
->result
);
732 } else if (m
->type
== JSONRPC_ERROR
) {
733 json_object_put(json
, "result", json_null_create());
737 json_object_put(json
, "error", m
->error
);
738 } else if (m
->type
== JSONRPC_REPLY
) {
739 json_object_put(json
, "error", json_null_create());
743 json_object_put(json
, "id", m
->id
);
744 } else if (m
->type
== JSONRPC_NOTIFY
) {
745 json_object_put(json
, "id", json_null_create());
753 /* A JSON-RPC session with reconnection. */
755 struct jsonrpc_session
{
756 struct reconnect
*reconnect
;
758 struct stream
*stream
;
759 struct pstream
*pstream
;
765 /* Creates and returns a jsonrpc_session to 'name', which should be a string
766 * acceptable to stream_open() or pstream_open().
768 * If 'name' is an active connection method, e.g. "tcp:127.1.2.3", the new
769 * jsonrpc_session connects to 'name'. If 'retry' is true, then the new
770 * session connects and reconnects to 'name', with backoff. If 'retry' is
771 * false, the new session will only try to connect once and after a connection
772 * failure or a disconnection jsonrpc_session_is_alive() will return false for
775 * If 'name' is a passive connection method, e.g. "ptcp:", the new
776 * jsonrpc_session listens for connections to 'name'. It maintains at most one
777 * connection at any given time. Any new connection causes the previous one
778 * (if any) to be dropped. */
779 struct jsonrpc_session
*
780 jsonrpc_session_open(const char *name
, bool retry
)
782 struct jsonrpc_session
*s
;
784 s
= xmalloc(sizeof *s
);
785 s
->reconnect
= reconnect_create(time_msec());
786 reconnect_set_name(s
->reconnect
, name
);
787 reconnect_enable(s
->reconnect
, time_msec());
795 if (!pstream_verify_name(name
)) {
796 reconnect_set_passive(s
->reconnect
, true, time_msec());
798 reconnect_set_max_tries(s
->reconnect
, 1);
799 reconnect_set_backoff(s
->reconnect
, INT_MAX
, INT_MAX
);
802 if (!stream_or_pstream_needs_probes(name
)) {
803 reconnect_set_probe_interval(s
->reconnect
, 0);
809 /* Creates and returns a jsonrpc_session that is initially connected to
810 * 'jsonrpc'. If the connection is dropped, it will not be reconnected.
812 * On the assumption that such connections are likely to be short-lived
813 * (e.g. from ovs-vsctl), informational logging for them is suppressed. */
814 struct jsonrpc_session
*
815 jsonrpc_session_open_unreliably(struct jsonrpc
*jsonrpc
, uint8_t dscp
)
817 struct jsonrpc_session
*s
;
819 s
= xmalloc(sizeof *s
);
820 s
->reconnect
= reconnect_create(time_msec());
821 reconnect_set_quiet(s
->reconnect
, true);
822 reconnect_set_name(s
->reconnect
, jsonrpc_get_name(jsonrpc
));
823 reconnect_set_max_tries(s
->reconnect
, 0);
824 reconnect_connected(s
->reconnect
, time_msec());
835 jsonrpc_session_close(struct jsonrpc_session
*s
)
838 jsonrpc_close(s
->rpc
);
839 reconnect_destroy(s
->reconnect
);
840 stream_close(s
->stream
);
841 pstream_close(s
->pstream
);
847 jsonrpc_session_disconnect(struct jsonrpc_session
*s
)
850 jsonrpc_error(s
->rpc
, EOF
);
851 jsonrpc_close(s
->rpc
);
854 } else if (s
->stream
) {
855 stream_close(s
->stream
);
862 jsonrpc_session_connect(struct jsonrpc_session
*s
)
864 const char *name
= reconnect_get_name(s
->reconnect
);
867 jsonrpc_session_disconnect(s
);
868 if (!reconnect_is_passive(s
->reconnect
)) {
869 error
= jsonrpc_stream_open(name
, &s
->stream
, s
->dscp
);
871 reconnect_connecting(s
->reconnect
, time_msec());
873 s
->last_error
= error
;
876 error
= s
->pstream
? 0 : jsonrpc_pstream_open(name
, &s
->pstream
,
879 reconnect_listening(s
->reconnect
, time_msec());
884 reconnect_connect_failed(s
->reconnect
, time_msec(), error
);
890 jsonrpc_session_run(struct jsonrpc_session
*s
)
893 struct stream
*stream
;
896 error
= pstream_accept(s
->pstream
, &stream
);
898 if (s
->rpc
|| s
->stream
) {
900 "%s: new connection replacing active connection",
901 reconnect_get_name(s
->reconnect
));
902 jsonrpc_session_disconnect(s
);
904 reconnect_connected(s
->reconnect
, time_msec());
905 s
->rpc
= jsonrpc_open(stream
);
906 } else if (error
!= EAGAIN
) {
907 reconnect_listen_error(s
->reconnect
, time_msec(), error
);
908 pstream_close(s
->pstream
);
917 backlog
= jsonrpc_get_backlog(s
->rpc
);
919 if (jsonrpc_get_backlog(s
->rpc
) < backlog
) {
920 /* Data previously caught in a queue was successfully sent (or
921 * there's an error, which we'll catch below.)
923 * We don't count data that is successfully sent immediately as
924 * activity, because there's a lot of queuing downstream from us,
925 * which means that we can push a lot of data into a connection
926 * that has stalled and won't ever recover.
928 reconnect_activity(s
->reconnect
, time_msec());
931 error
= jsonrpc_get_status(s
->rpc
);
933 reconnect_disconnected(s
->reconnect
, time_msec(), error
);
934 jsonrpc_session_disconnect(s
);
935 s
->last_error
= error
;
937 } else if (s
->stream
) {
940 stream_run(s
->stream
);
941 error
= stream_connect(s
->stream
);
943 reconnect_connected(s
->reconnect
, time_msec());
944 s
->rpc
= jsonrpc_open(s
->stream
);
946 } else if (error
!= EAGAIN
) {
947 reconnect_connect_failed(s
->reconnect
, time_msec(), error
);
948 stream_close(s
->stream
);
950 s
->last_error
= error
;
954 switch (reconnect_run(s
->reconnect
, time_msec())) {
955 case RECONNECT_CONNECT
:
956 jsonrpc_session_connect(s
);
959 case RECONNECT_DISCONNECT
:
960 reconnect_disconnected(s
->reconnect
, time_msec(), 0);
961 jsonrpc_session_disconnect(s
);
964 case RECONNECT_PROBE
:
967 struct jsonrpc_msg
*request
;
969 params
= json_array_create_empty();
970 request
= jsonrpc_create_request("echo", params
, NULL
);
971 json_destroy(request
->id
);
972 request
->id
= json_string_create("echo");
973 jsonrpc_send(s
->rpc
, request
);
980 jsonrpc_session_wait(struct jsonrpc_session
*s
)
983 jsonrpc_wait(s
->rpc
);
984 } else if (s
->stream
) {
985 stream_run_wait(s
->stream
);
986 stream_connect_wait(s
->stream
);
989 pstream_wait(s
->pstream
);
991 reconnect_wait(s
->reconnect
, time_msec());
995 jsonrpc_session_get_backlog(const struct jsonrpc_session
*s
)
997 return s
->rpc
? jsonrpc_get_backlog(s
->rpc
) : 0;
1000 /* Always returns a pointer to a valid C string, assuming 's' was initialized
1003 jsonrpc_session_get_name(const struct jsonrpc_session
*s
)
1005 return reconnect_get_name(s
->reconnect
);
1008 /* Always takes ownership of 'msg', regardless of success. */
1010 jsonrpc_session_send(struct jsonrpc_session
*s
, struct jsonrpc_msg
*msg
)
1013 return jsonrpc_send(s
->rpc
, msg
);
1015 jsonrpc_msg_destroy(msg
);
1020 struct jsonrpc_msg
*
1021 jsonrpc_session_recv(struct jsonrpc_session
*s
)
1024 unsigned int received_bytes
;
1025 struct jsonrpc_msg
*msg
;
1027 received_bytes
= jsonrpc_get_received_bytes(s
->rpc
);
1028 jsonrpc_recv(s
->rpc
, &msg
);
1029 if (received_bytes
!= jsonrpc_get_received_bytes(s
->rpc
)) {
1030 /* Data was successfully received.
1032 * Previously we only counted receiving a full message as activity,
1033 * but with large messages or a slow connection that policy could
1034 * time out the session mid-message. */
1035 reconnect_activity(s
->reconnect
, time_msec());
1039 if (msg
->type
== JSONRPC_REQUEST
&& !strcmp(msg
->method
, "echo")) {
1040 /* Echo request. Send reply. */
1041 struct jsonrpc_msg
*reply
;
1043 reply
= jsonrpc_create_reply(json_clone(msg
->params
), msg
->id
);
1044 jsonrpc_session_send(s
, reply
);
1045 } else if (msg
->type
== JSONRPC_REPLY
1046 && msg
->id
&& msg
->id
->type
== JSON_STRING
1047 && !strcmp(msg
->id
->u
.string
, "echo")) {
1048 /* It's a reply to our echo request. Suppress it. */
1052 jsonrpc_msg_destroy(msg
);
1059 jsonrpc_session_recv_wait(struct jsonrpc_session
*s
)
1062 jsonrpc_recv_wait(s
->rpc
);
1066 /* Returns true if 's' is currently connected or trying to connect. */
1068 jsonrpc_session_is_alive(const struct jsonrpc_session
*s
)
1070 return s
->rpc
|| s
->stream
|| reconnect_get_max_tries(s
->reconnect
);
1073 /* Returns true if 's' is currently connected. */
1075 jsonrpc_session_is_connected(const struct jsonrpc_session
*s
)
1077 return s
->rpc
!= NULL
;
1080 /* Returns a sequence number for 's'. The sequence number increments every
1081 * time 's' connects or disconnects. Thus, a caller can use the change (or
1082 * lack of change) in the sequence number to figure out whether the underlying
1083 * connection is the same as before. */
1085 jsonrpc_session_get_seqno(const struct jsonrpc_session
*s
)
1090 /* Returns the current status of 's'. If 's' is NULL or is disconnected, this
1091 * is 0, otherwise it is the status of the connection, as reported by
1092 * jsonrpc_get_status(). */
1094 jsonrpc_session_get_status(const struct jsonrpc_session
*s
)
1096 return s
&& s
->rpc
? jsonrpc_get_status(s
->rpc
) : 0;
1099 /* Returns the last error reported on a connection by 's'. The return value is
1100 * 0 only if no connection made by 's' has ever encountered an error. See
1101 * jsonrpc_get_status() for return value interpretation. */
1103 jsonrpc_session_get_last_error(const struct jsonrpc_session
*s
)
1105 return s
->last_error
;
1108 /* Populates 'stats' with statistics from 's'. */
1110 jsonrpc_session_get_reconnect_stats(const struct jsonrpc_session
*s
,
1111 struct reconnect_stats
*stats
)
1113 reconnect_get_stats(s
->reconnect
, time_msec(), stats
);
1116 /* Enables 's' to reconnect to the peer if the connection drops. */
1118 jsonrpc_session_enable_reconnect(struct jsonrpc_session
*s
)
1120 reconnect_set_max_tries(s
->reconnect
, UINT_MAX
);
1121 reconnect_set_backoff(s
->reconnect
, RECONNECT_DEFAULT_MIN_BACKOFF
,
1122 RECONNECT_DEFAULT_MAX_BACKOFF
);
1125 /* Forces 's' to drop its connection (if any) and reconnect. */
1127 jsonrpc_session_force_reconnect(struct jsonrpc_session
*s
)
1129 reconnect_force_reconnect(s
->reconnect
, time_msec());
1132 /* Sets 'max_backoff' as the maximum time, in milliseconds, to wait after a
1133 * connection attempt fails before attempting to connect again. */
1135 jsonrpc_session_set_max_backoff(struct jsonrpc_session
*s
, int max_backoff
)
1137 reconnect_set_backoff(s
->reconnect
, 0, max_backoff
);
1140 /* Sets the "probe interval" for 's' to 'probe_interval', in milliseconds. If
1141 * this is zero, it disables the connection keepalive feature. Otherwise, if
1142 * 's' is idle for 'probe_interval' milliseconds then 's' will send an echo
1143 * request and, if no reply is received within an additional 'probe_interval'
1144 * milliseconds, close the connection (then reconnect, if that feature is
1147 jsonrpc_session_set_probe_interval(struct jsonrpc_session
*s
,
1150 reconnect_set_probe_interval(s
->reconnect
, probe_interval
);
1153 /* Sets the DSCP value used for 's''s connection to 'dscp'. If this is
1154 * different from the DSCP value currently in use then the connection is closed
1155 * and reconnected. */
1157 jsonrpc_session_set_dscp(struct jsonrpc_session
*s
, uint8_t dscp
)
1159 if (s
->dscp
!= dscp
) {
1160 pstream_close(s
->pstream
);
1164 jsonrpc_session_force_reconnect(s
);