Add a RunTesting option to try to learn link state by creating test circuits, even when SocksPort is off.

svn:r1327

src/or/circuit.c

@@ -907,6 +907,9 @@ void circuit_dump_by_conn(connection_t *conn, int severity) {
   }
 }
 
+/* Expire unused testing circuits after 10 minutes. */
+#define TESTING_CIRCUIT_MAX_AGE 600
+
 void circuit_expire_unused_circuits(void) {
   circuit_t *circ, *tmpcirc;
   time_t now = time(NULL);
@@ -915,9 +918,18 @@ void circuit_expire_unused_circuits(void) {
   while(circ) {
     tmpcirc = circ;
     circ = circ->next;
-    if(tmpcirc->timestamp_dirty &&
-       tmpcirc->timestamp_dirty + options.NewCircuitPeriod < now &&
-       !tmpcirc->p_conn && !tmpcirc->p_streams && !tmpcirc->marked_for_close) {
+    /* If the circuit has been dirty for too long, and there are no streams
+     * on it, mark it for close.
+     * If we are creating test circuits, and the circuit is old, and has
+     * no streams, shut it down even if it isn't dirty.
+     */
+    if(((tmpcirc->timestamp_dirty &&
+         tmpcirc->timestamp_dirty + options.NewCircuitPeriod < now) ||
+        (options.RunTesting &&
+         tmpcirc->timestamp_created + TESTING_CIRCUIT_MAX_AGE < now))
+       && !tmpcirc->p_conn
+       && !tmpcirc->p_streams
+       && !tmpcirc->marked_for_close) {
       log_fn(LOG_DEBUG,"Closing n_circ_id %d",tmpcirc->n_circ_id);
       circuit_mark_for_close(tmpcirc);
     }
@@ -932,7 +944,7 @@ static int n_circuit_failures = 0;
 /* Return -1 if you aren't going to try to make a circuit, 0 if you did try. */
 int circuit_launch_new(void) {
 
-  if(!options.SocksPort) /* we're not an application proxy. no need for circuits. */
+  if(!(options.SocksPort||options.RunTesting)) /* no need for circuits. */
     return -1;
 
   if(n_circuit_failures > 5) { /* too many failed circs in a row. don't try. */

src/or/config.c

@@ -201,7 +201,8 @@ static int config_assign(or_options_t *options, struct config_line *list) {
 
     config_compare(list, "TrafficShaping", CONFIG_TYPE_BOOL, &options->TrafficShaping) ||
 
-    config_compare(list, "User",           CONFIG_TYPE_STRING, &options->User)
+    config_compare(list, "User",           CONFIG_TYPE_STRING, &options->User) ||
+    config_compare(list, "RunTesting",     CONFIG_TYPE_BOOL, &options->RunTesting)
     ) {
       /* then we're ok. it matched something. */
     } else {

src/or/connection_or.c

@@ -243,11 +243,8 @@ static int connection_tls_finish_handshake(connection_t *conn) {
   }
   if (!options.ORPort) { /* If I'm an OP... */
     conn->receiver_bucket = conn->bandwidth = DEFAULT_BANDWIDTH_OP;
-    circuit_n_conn_open(conn); /* send the pending creates, if any. */
-    /* XXXX ORs may need to send creates for test circuits; "I am an OR"
-     * doesn't mean "I have no pending creates", right?
-     */
   }
+  circuit_n_conn_open(conn); /* send the pending creates, if any. */
   /* Note the success */
   rep_hist_note_connect_succeeded(nickname, time(NULL));
   return 0;

src/or/main.c

@@ -354,10 +354,14 @@ static void run_scheduled_events(time_t now) {
    *    that became dirty more than NewCircuitPeriod seconds ago,
    *    and we make a new circ if there are no clean circuits.
    */
-  if(options.SocksPort) {
+  if(options.SocksPort || options.RunTesting) {
+
+    if (options.SocksPort)
+      /* launch a new circ for any pending streams that need one */
+      connection_ap_attach_pending();
 
-    /* launch a new circ for any pending streams that need one */
-    connection_ap_attach_pending();
+/* Build a new test circuit every 5 minutes */
+#define TESTING_CIRCUIT_INTERVAL 300
 
     circ = circuit_get_newest(NULL, 1);
     if(time_to_new_circuit < now) {
@@ -367,6 +371,10 @@ static void run_scheduled_events(time_t now) {
       if(circ && circ->timestamp_dirty) {
         log_fn(LOG_INFO,"Youngest circuit dirty; launching replacement.");
         circuit_launch_new(); /* make a new circuit */
+      } else if (options.RunTesting && circ &&
+                 circ->timestamp_created + TESTING_CIRCUIT_INTERVAL < now) {
+        log_fn(LOG_INFO,"Creating a new testing circuit.");
+        circuit_launch_new();
       }
       time_to_new_circuit = now + options.NewCircuitPeriod;
     }

src/or/or.h

@@ -544,6 +544,7 @@ typedef struct {
   int BandwidthBurst;
   int NumCpus;
   int loglevel;
+  int RunTesting;
 } or_options_t;
 
 /* XXX are these good enough defaults? */