Rework origin circuit tracking to use pubsub

Part of ticket 29976.

src/app/main/main.c

@@ -1257,6 +1257,7 @@ pubsub_connect(void)
      * this XXXX point, using tor_mainloop_set_delivery_strategy().
      */
     tor_mainloop_set_delivery_strategy("orconn", DELIV_IMMEDIATE);
+    tor_mainloop_set_delivery_strategy("ocirc", DELIV_IMMEDIATE);
   }
 }
 

src/core/or/circuitbuild.c

@@ -522,14 +522,13 @@ origin_circuit_get_guard_state(origin_circuit_t *circ)
 static void
 circuit_chan_publish(const origin_circuit_t *circ, const channel_t *chan)
 {
-  ocirc_event_msg_t msg;
+  ocirc_chan_msg_t *msg = tor_malloc(sizeof(*msg));
 
-  msg.type = OCIRC_MSGTYPE_CHAN;
-  msg.u.chan.gid = circ->global_identifier;
-  msg.u.chan.chan = chan->global_identifier;
-  msg.u.chan.onehop = circ->build_state->onehop_tunnel;
+  msg->gid = circ->global_identifier;
+  msg->chan = chan->global_identifier;
+  msg->onehop = circ->build_state->onehop_tunnel;
 
-  ocirc_event_publish(&msg);
+  ocirc_chan_publish(msg);
 }
 
 /** Start establishing the first hop of our circuit. Figure out what

src/core/or/circuitlist.c

@@ -496,17 +496,16 @@ int
 circuit_event_status(origin_circuit_t *circ, circuit_status_event_t tp,
                      int reason_code)
 {
-  ocirc_event_msg_t msg;
+  ocirc_cevent_msg_t *msg = tor_malloc(sizeof(*msg));
 
   tor_assert(circ);
 
-  msg.type = OCIRC_MSGTYPE_CEVENT;
-  msg.u.cevent.gid = circ->global_identifier;
-  msg.u.cevent.evtype = tp;
-  msg.u.cevent.reason = reason_code;
-  msg.u.cevent.onehop = circ->build_state->onehop_tunnel;
+  msg->gid = circ->global_identifier;
+  msg->evtype = tp;
+  msg->reason = reason_code;
+  msg->onehop = circ->build_state->onehop_tunnel;
 
-  ocirc_event_publish(&msg);
+  ocirc_cevent_publish(msg);
   return control_event_circuit_status(circ, tp, reason_code);
 }
 
@@ -514,26 +513,25 @@ circuit_event_status(origin_circuit_t *circ, circuit_status_event_t tp,
  * Helper function to publish a state change message
  *
  * circuit_set_state() calls this to notify subscribers about a change
- * of the state of an origin circuit.
+ * of the state of an origin circuit.  @a circ must be an origin
+ * circuit.
  **/
 static void
 circuit_state_publish(const circuit_t *circ)
 {
-  ocirc_event_msg_t msg;
+  ocirc_state_msg_t *msg = tor_malloc(sizeof(*msg));
   const origin_circuit_t *ocirc;
 
-  if (!CIRCUIT_IS_ORIGIN(circ))
-    return;
+  tor_assert(CIRCUIT_IS_ORIGIN(circ));
   ocirc = CONST_TO_ORIGIN_CIRCUIT(circ);
   /* Only inbound OR circuits can be in this state, not origin circuits. */
   tor_assert(circ->state != CIRCUIT_STATE_ONIONSKIN_PENDING);
 
-  msg.type = OCIRC_MSGTYPE_STATE;
-  msg.u.state.gid = ocirc->global_identifier;
-  msg.u.state.state = circ->state;
-  msg.u.state.onehop = ocirc->build_state->onehop_tunnel;
+  msg->gid = ocirc->global_identifier;
+  msg->state = circ->state;
+  msg->onehop = ocirc->build_state->onehop_tunnel;
 
-  ocirc_event_publish(&msg);
+  ocirc_state_publish(msg);
 }
 
 /** Change the state of <b>circ</b> to <b>state</b>, adding it to or removing
@@ -565,7 +563,8 @@ circuit_set_state(circuit_t *circ, uint8_t state)
   if (state == CIRCUIT_STATE_GUARD_WAIT || state == CIRCUIT_STATE_OPEN)
     tor_assert(!circ->n_chan_create_cell);
   circ->state = state;
-  circuit_state_publish(circ);
+  if (CIRCUIT_IS_ORIGIN(circ))
+    circuit_state_publish(circ);
 }
 
 /** Append to <b>out</b> all circuits in state CHAN_WAIT waiting for

src/core/or/ocirc_event.c

@@ -26,59 +26,103 @@
 #include "core/or/origin_circuit_st.h"
 #include "lib/subsys/subsys.h"
 
-/** List of subscribers */
-static smartlist_t *ocirc_event_rcvrs;
+DECLARE_PUBLISH(ocirc_state);
+DECLARE_PUBLISH(ocirc_chan);
+DECLARE_PUBLISH(ocirc_cevent);
 
-/** Initialize subscriber list */
-static int
-ocirc_event_init(void)
+static void
+ocirc_event_free(msg_aux_data_t u)
 {
-  ocirc_event_rcvrs = smartlist_new();
+  tor_free_(u.ptr);
+}
+
+static char *
+ocirc_state_fmt(msg_aux_data_t u)
+{
+  ocirc_state_msg_t *msg = (ocirc_state_msg_t *)u.ptr;
+  char *s = NULL;
+
+  tor_asprintf(&s, "<gid=%"PRIu32" state=%d onehop=%d>",
+               msg->gid, msg->state, msg->onehop);
+  return s;
+}
+
+static char *
+ocirc_chan_fmt(msg_aux_data_t u)
+{
+  ocirc_chan_msg_t *msg = (ocirc_chan_msg_t *)u.ptr;
+  char *s = NULL;
+
+  tor_asprintf(&s, "<gid=%"PRIu32" chan=%"PRIu64" onehop=%d>",
+               msg->gid, msg->chan, msg->onehop);
+  return s;
+}
+
+static char *
+ocirc_cevent_fmt(msg_aux_data_t u)
+{
+  ocirc_cevent_msg_t *msg = (ocirc_cevent_msg_t *)u.ptr;
+  char *s = NULL;
+
+  tor_asprintf(&s, "<gid=%"PRIu32" evtype=%d reason=%d onehop=%d>",
+               msg->gid, msg->evtype, msg->reason, msg->onehop);
+  return s;
+}
+
+static dispatch_typefns_t ocirc_state_fns = {
+  .free_fn = ocirc_event_free,
+  .fmt_fn = ocirc_state_fmt,
+};
+
+static dispatch_typefns_t ocirc_chan_fns = {
+  .free_fn = ocirc_event_free,
+  .fmt_fn = ocirc_chan_fmt,
+};
+
+static dispatch_typefns_t ocirc_cevent_fns = {
+  .free_fn = ocirc_event_free,
+  .fmt_fn = ocirc_cevent_fmt,
+};
+
+static int
+ocirc_add_pubsub(struct pubsub_connector_t *connector)
+{
+  if (DISPATCH_REGISTER_TYPE(connector, ocirc_state, &ocirc_state_fns))
+    return -1;
+  if (DISPATCH_REGISTER_TYPE(connector, ocirc_chan, &ocirc_chan_fns))
+    return -1;
+  if (DISPATCH_REGISTER_TYPE(connector, ocirc_cevent, &ocirc_cevent_fns))
+    return -1;
+  if (DISPATCH_ADD_PUB(connector, ocirc, ocirc_state))
+    return -1;
+  if (DISPATCH_ADD_PUB(connector, ocirc, ocirc_chan))
+    return -1;
+  if (DISPATCH_ADD_PUB(connector, ocirc, ocirc_cevent))
+    return -1;
   return 0;
 }
 
-/** Free subscriber list */
-static void
-ocirc_event_fini(void)
+void
+ocirc_state_publish(ocirc_state_msg_t *msg)
 {
-  smartlist_free(ocirc_event_rcvrs);
+  PUBLISH(ocirc_state, msg);
 }
 
-/**
- * Subscribe to messages about origin circuit events
- *
- * Register a callback function to receive messages about origin
- * circuits.  The publisher calls this function synchronously.
- **/
 void
-ocirc_event_subscribe(ocirc_event_rcvr_t fn)
+ocirc_chan_publish(ocirc_chan_msg_t *msg)
 {
-  tor_assert(fn);
-  /* Don't duplicate subscriptions. */
-  if (smartlist_contains(ocirc_event_rcvrs, fn))
-    return;
-
-  smartlist_add(ocirc_event_rcvrs, fn);
+  PUBLISH(ocirc_chan, msg);
 }
 
-/**
- * Publish a message about OR connection events
- *
- * This calls the subscriber receiver function synchronously.
- **/
 void
-ocirc_event_publish(const ocirc_event_msg_t *msg)
+ocirc_cevent_publish(ocirc_cevent_msg_t *msg)
 {
-  SMARTLIST_FOREACH_BEGIN(ocirc_event_rcvrs, ocirc_event_rcvr_t, fn) {
-    tor_assert(fn);
-    (*fn)(msg);
-  } SMARTLIST_FOREACH_END(fn);
+  PUBLISH(ocirc_cevent, msg);
 }
 
 const subsys_fns_t sys_ocirc_event = {
   .name = "ocirc_event",
   .supported = true,
   .level = -32,
-  .initialize = ocirc_event_init,
-  .shutdown = ocirc_event_fini,
+  .add_pubsub = ocirc_add_pubsub,
 };

src/core/or/ocirc_event.h

@@ -12,6 +12,7 @@
 #include <stdbool.h>
 
 #include "lib/cc/torint.h"
+#include "lib/pubsub/pubsub.h"
 
 /** Used to indicate the type of a circuit event passed to the controller.
  * The various types are defined in control-spec.txt */
@@ -30,6 +31,8 @@ typedef struct ocirc_state_msg_t {
   bool onehop;        /**< one-hop circuit? */
 } ocirc_state_msg_t;
 
+DECLARE_MESSAGE(ocirc_state, ocirc_state, ocirc_state_msg_t *);
+
 /**
  * Message when a channel gets associated to a circuit.
  *
@@ -44,6 +47,8 @@ typedef struct ocirc_chan_msg_t {
   bool onehop;                  /**< one-hop circuit? */
 } ocirc_chan_msg_t;
 
+DECLARE_MESSAGE(ocirc_chan, ocirc_chan, ocirc_chan_msg_t *);
+
 /**
  * Message for origin circuit status event
  *
@@ -56,34 +61,12 @@ typedef struct ocirc_cevent_msg_t {
   bool onehop;                  /**< one-hop circuit? */
 } ocirc_cevent_msg_t;
 
-/** Discriminant values for origin circuit event message */
-typedef enum ocirc_msgtype_t {
-  OCIRC_MSGTYPE_STATE,
-  OCIRC_MSGTYPE_CHAN,
-  OCIRC_MSGTYPE_CEVENT,
-} ocirc_msgtype_t;
-
-/** Discriminated union for the actual message */
-typedef struct ocirc_event_msg_t {
-  int type;
-  union {
-    ocirc_state_msg_t state;
-    ocirc_chan_msg_t chan;
-    ocirc_cevent_msg_t cevent;
-  } u;
-} ocirc_event_msg_t;
-
-/**
- * Receiver function pointer for origin circuit subscribers
- *
- * This function gets called synchronously by the publisher.
- **/
-typedef void (*ocirc_event_rcvr_t)(const ocirc_event_msg_t *);
-
-void ocirc_event_subscribe(ocirc_event_rcvr_t fn);
+DECLARE_MESSAGE(ocirc_cevent, ocirc_cevent, ocirc_cevent_msg_t *);
 
 #ifdef OCIRC_EVENT_PRIVATE
-void ocirc_event_publish(const ocirc_event_msg_t *msg);
+void ocirc_state_publish(ocirc_state_msg_t *msg);
+void ocirc_chan_publish(ocirc_chan_msg_t *msg);
+void ocirc_cevent_publish(ocirc_cevent_msg_t *msg);
 #endif
 
 #endif  /* defined(TOR_OCIRC_EVENT_STATE_H) */

src/feature/control/btrack.c

@@ -32,8 +32,6 @@ btrack_init(void)
 {
   if (btrack_orconn_init())
     return -1;
-  if (btrack_circ_init())
-    return -1;
 
   return 0;
 }
@@ -48,7 +46,12 @@ btrack_fini(void)
 static int
 btrack_add_pubsub(pubsub_connector_t *connector)
 {
-  return btrack_orconn_add_pubsub(connector);
+  if (btrack_orconn_add_pubsub(connector))
+    return -1;
+  if (btrack_circ_add_pubsub(connector))
+    return -1;
+
+  return 0;
 }
 
 const subsys_fns_t sys_btrack = {

src/feature/control/btrack_circuit.c

@@ -109,51 +109,53 @@ btc_update_evtype(const ocirc_cevent_msg_t *msg, btc_best_t *best,
   return false;
 }
 
+DECLARE_SUBSCRIBE(ocirc_state, btc_state_rcvr);
+DECLARE_SUBSCRIBE(ocirc_cevent, btc_cevent_rcvr);
+DECLARE_SUBSCRIBE(ocirc_chan, btc_chan_rcvr);
+
 static void
-btc_state_rcvr(const ocirc_state_msg_t *msg)
+btc_state_rcvr(const msg_t *msg, const ocirc_state_msg_t *arg)
 {
+  (void)msg;
   log_debug(LD_BTRACK, "CIRC gid=%"PRIu32" state=%d onehop=%d",
-            msg->gid, msg->state, msg->onehop);
+            arg->gid, arg->state, arg->onehop);
 
-  btc_update_state(msg, &best_any_state, "ANY");
-  if (msg->onehop)
+  btc_update_state(arg, &best_any_state, "ANY");
+  if (arg->onehop)
     return;
-  btc_update_state(msg, &best_ap_state, "AP");
+  btc_update_state(arg, &best_ap_state, "AP");
 }
 
 static void
-btc_cevent_rcvr(const ocirc_cevent_msg_t *msg)
+btc_cevent_rcvr(const msg_t *msg, const ocirc_cevent_msg_t *arg)
 {
+  (void)msg;
   log_debug(LD_BTRACK, "CIRC gid=%"PRIu32" evtype=%d reason=%d onehop=%d",
-            msg->gid, msg->evtype, msg->reason, msg->onehop);
+            arg->gid, arg->evtype, arg->reason, arg->onehop);
 
-  btc_update_evtype(msg, &best_any_evtype, "ANY");
-  if (msg->onehop)
+  btc_update_evtype(arg, &best_any_evtype, "ANY");
+  if (arg->onehop)
     return;
-  btc_update_evtype(msg, &best_ap_evtype, "AP");
+  btc_update_evtype(arg, &best_ap_evtype, "AP");
 }
 
 static void
-btc_event_rcvr(const ocirc_event_msg_t *msg)
+btc_chan_rcvr(const msg_t *msg, const ocirc_chan_msg_t *arg)
 {
-  switch (msg->type) {
-  case OCIRC_MSGTYPE_STATE:
-    return btc_state_rcvr(&msg->u.state);
-  case OCIRC_MSGTYPE_CHAN:
-    log_debug(LD_BTRACK, "CIRC gid=%"PRIu32" chan=%"PRIu64" onehop=%d",
-              msg->u.chan.gid, msg->u.chan.chan, msg->u.chan.onehop);
-    break;
-  case OCIRC_MSGTYPE_CEVENT:
-    return btc_cevent_rcvr(&msg->u.cevent);
-  default:
-    break;
-  }
+  (void)msg;
+  log_debug(LD_BTRACK, "CIRC gid=%"PRIu32" chan=%"PRIu64" onehop=%d",
+            arg->gid, arg->chan, arg->onehop);
 }
 
 int
-btrack_circ_init(void)
+btrack_circ_add_pubsub(pubsub_connector_t *connector)
 {
-  ocirc_event_subscribe(btc_event_rcvr);
+  if (DISPATCH_ADD_SUB(connector, ocirc, ocirc_chan))
+    return -1;
+  if (DISPATCH_ADD_SUB(connector, ocirc, ocirc_cevent))
+    return -1;
+  if (DISPATCH_ADD_SUB(connector, ocirc, ocirc_state))
+    return -1;
   return 0;
 }
 

src/feature/control/btrack_circuit.h

@@ -9,7 +9,10 @@
 #ifndef TOR_BTRACK_CIRCUIT_H
 #define TOR_BTRACK_CIRCUIT_H
 
+#include "lib/pubsub/pubsub.h"
+
 int btrack_circ_init(void);
 void btrack_circ_fini(void);
+int btrack_circ_add_pubsub(pubsub_connector_t *);
 
 #endif  /* defined(TOR_BTRACK_CIRCUIT_H) */

src/feature/control/btrack_orconn.c

@@ -49,6 +49,7 @@
 
 DECLARE_SUBSCRIBE(orconn_state, bto_state_rcvr);
 DECLARE_SUBSCRIBE(orconn_status, bto_status_rcvr);
+DECLARE_SUBSCRIBE(ocirc_chan, bto_chan_rcvr);
 
 /** Pair of a best ORCONN GID and with its state */
 typedef struct bto_best_t {
@@ -155,21 +156,18 @@ bto_status_rcvr(const msg_t *msg, const orconn_status_msg_t *arg)
  * and whether it's a one-hop circuit.
  **/
 static void
-bto_chan_rcvr(const ocirc_event_msg_t *msg)
+bto_chan_rcvr(const msg_t *msg, const ocirc_chan_msg_t *arg)
 {
   bt_orconn_t *bto;
 
-  /* Ignore other kinds of origin circuit events; we don't need them */
-  if (msg->type != OCIRC_MSGTYPE_CHAN)
-    return;
-
-  bto = bto_find_or_new(0, msg->u.chan.chan);
-  if (!bto->is_orig || (bto->is_onehop && !msg->u.chan.onehop)) {
+  (void)msg;
+  bto = bto_find_or_new(0, arg->chan);
+  if (!bto->is_orig || (bto->is_onehop && !arg->onehop)) {
     log_debug(LD_BTRACK, "ORCONN LAUNCH chan=%"PRIu64" onehop=%d",
-              msg->u.chan.chan, msg->u.chan.onehop);
+              arg->chan, arg->onehop);
   }
   bto->is_orig = true;
-  if (!msg->u.chan.onehop)
+  if (!arg->onehop)
     bto->is_onehop = false;
   bto_update_bests(bto);
 }
@@ -182,7 +180,6 @@ int
 btrack_orconn_init(void)
 {
   bto_init_maps();
-  ocirc_event_subscribe(bto_chan_rcvr);
 
   return 0;
 }
@@ -194,6 +191,8 @@ btrack_orconn_add_pubsub(pubsub_connector_t *connector)
     return -1;
   if (DISPATCH_ADD_SUB(connector, orconn, orconn_status))
     return -1;
+  if (DISPATCH_ADD_SUB(connector, ocirc, ocirc_chan))
+    return -1;
   return 0;
 }
 

src/test/test_btrack.c

@@ -30,11 +30,20 @@ send_status(const orconn_status_msg_t *msg_in)
   orconn_status_publish(msg);
 }
 
+static void
+send_chan(const ocirc_chan_msg_t *msg_in)
+{
+  ocirc_chan_msg_t *msg = tor_malloc(sizeof(*msg));
+
+  *msg = *msg_in;
+  ocirc_chan_publish(msg);
+}
+
 static void
 test_btrack_launch(void *arg)
 {
   orconn_state_msg_t conn;
-  ocirc_event_msg_t circ;
+  ocirc_chan_msg_t circ;
 
   (void)arg;
   conn.gid = 1;
@@ -48,12 +57,11 @@ test_btrack_launch(void *arg)
   expect_no_log_msg_containing("ORCONN BEST_");
   teardown_capture_of_logs();
 
-  circ.type = OCIRC_MSGTYPE_CHAN;
-  circ.u.chan.chan = 1;
-  circ.u.chan.onehop = true;
+  circ.chan = 1;
+  circ.onehop = true;
 
   setup_full_capture_of_logs(LOG_DEBUG);
-  ocirc_event_publish(&circ);
+  send_chan(&circ);
   expect_log_msg_containing("ORCONN LAUNCH chan=1 onehop=1");
   expect_log_msg_containing("ORCONN BEST_ANY state -1->1 gid=1");
   teardown_capture_of_logs();
@@ -67,11 +75,11 @@ test_btrack_launch(void *arg)
   expect_no_log_msg_containing("ORCONN BEST_");
   teardown_capture_of_logs();
 
-  circ.u.chan.chan = 2;
-  circ.u.chan.onehop = false;
+  circ.chan = 2;
+  circ.onehop = false;
 
   setup_full_capture_of_logs(LOG_DEBUG);
-  ocirc_event_publish(&circ);
+  send_chan(&circ);
   expect_log_msg_containing("ORCONN LAUNCH chan=2 onehop=0");
   expect_log_msg_containing("ORCONN BEST_AP state -1->1 gid=2");
   teardown_capture_of_logs();

src/test/test_circuitstats.c

@@ -197,7 +197,7 @@ test_circuitstats_hoplen(void *arg)
 }
 
 #define TEST_CIRCUITSTATS(name, flags) \
-    { #name, test_##name, (flags), NULL, NULL }
+    { #name, test_##name, (flags), &helper_pubsub_setup, NULL }
 
 struct testcase_t circuitstats_tests[] = {
   TEST_CIRCUITSTATS(circuitstats_hoplen, TT_FORK),

src/test/test_controller_events.c

@@ -417,13 +417,12 @@ send_orconn_state(const orconn_state_msg_t *msg_in, uint8_t state)
 static void
 send_ocirc_chan(uint32_t gid, uint64_t chan, bool onehop)
 {
-  ocirc_event_msg_t msg;
+  ocirc_chan_msg_t *msg = tor_malloc(sizeof(*msg));
 
-  msg.type = OCIRC_MSGTYPE_CHAN;
-  msg.u.chan.gid = gid;
-  msg.u.chan.chan = chan;
-  msg.u.chan.onehop = onehop;
-  ocirc_event_publish(&msg);
+  msg->gid = gid;
+  msg->chan = chan;
+  msg->onehop = onehop;
+  ocirc_chan_publish(msg);
 }
 
 static void

src/test/test_helpers.c

@@ -338,6 +338,8 @@ helper_setup_pubsub(const struct testcase_t *testcase)
   dispatcher = pubsub_builder_finalize(builder, NULL);
   tor_assert(dispatcher);
   dispatch_set_alert_fn(dispatcher, chan, alertfn_immediate, NULL);
+  chan = get_channel_id("ocirc");
+  dispatch_set_alert_fn(dispatcher, chan, alertfn_immediate, NULL);
   return dispatcher;
 }