Hiding crypt_path_t: Move some more crypt_path-specific functions.

- Move test-only cpath_get_n_hops() to crypt_path.c.
- Move onion_next_hop_in_cpath() and rename to cpath_get_next_non_open_hop().

The latter function was directly accessing cpath->state, and it's a first step
at hiding ->state.

src/core/or/circuitbuild.c

@@ -91,7 +91,6 @@ static channel_t * channel_connect_for_circuit(const tor_addr_t *addr,
 static int circuit_deliver_create_cell(circuit_t *circ,
                                        const create_cell_t *create_cell,
                                        int relayed);
-static crypt_path_t *onion_next_hop_in_cpath(crypt_path_t *cpath);
 static int circuit_send_first_onion_skin(origin_circuit_t *circ);
 static int circuit_build_no_more_hops(origin_circuit_t *circ);
 static int circuit_send_intermediate_onion_skin(origin_circuit_t *circ,
@@ -547,7 +546,7 @@ circuit_handle_first_hop(origin_circuit_t *circ)
   int should_launch = 0;
   const or_options_t *options = get_options();
 
-  firsthop = onion_next_hop_in_cpath(circ->cpath);
+  firsthop = cpath_get_next_non_open_hop(circ->cpath);
   tor_assert(firsthop);
   tor_assert(firsthop->extend_info);
 
@@ -948,7 +947,7 @@ circuit_send_next_onion_skin(origin_circuit_t *circ)
   tor_assert(circ->cpath->state == CPATH_STATE_OPEN);
   tor_assert(circ->base_.state == CIRCUIT_STATE_BUILDING);
 
-  crypt_path_t *hop = onion_next_hop_in_cpath(circ->cpath);
+  crypt_path_t *hop = cpath_get_next_non_open_hop(circ->cpath);
   circuit_build_times_handle_completed_hop(circ);
 
   circpad_machine_event_circ_added_hop(circ);
@@ -1385,7 +1384,7 @@ circuit_finish_handshake(origin_circuit_t *circ,
   if (circ->cpath->state == CPATH_STATE_AWAITING_KEYS) {
     hop = circ->cpath;
   } else {
-    hop = onion_next_hop_in_cpath(circ->cpath);
+    hop = cpath_get_next_non_open_hop(circ->cpath);
     if (!hop) { /* got an extended when we're all done? */
       log_warn(LD_PROTOCOL,"got extended when circ already built? Closing.");
       return - END_CIRC_REASON_TORPROTOCOL;
@@ -2345,30 +2344,6 @@ count_acceptable_nodes, (const smartlist_t *nodes, int direct))
   return num;
 }
 
-#ifdef TOR_UNIT_TESTS
-
-/** Unittest helper function: Count number of hops in cpath linked list. */
-unsigned int
-cpath_get_n_hops(crypt_path_t **head_ptr)
-{
-  unsigned int n_hops = 0;
-  crypt_path_t *tmp;
-
-  if (!*head_ptr) {
-    return 0;
-  }
-
-  tmp = *head_ptr;
-  do {
-    n_hops++;
-    tmp = tmp->next;
-  } while (tmp != *head_ptr);
-
-  return n_hops;
-}
-
-#endif /* defined(TOR_UNIT_TESTS) */
-
 /**
  * Build the exclude list for vanguard circuits.
  *
@@ -2643,20 +2618,6 @@ choose_good_entry_server(uint8_t purpose, cpath_build_state_t *state,
   return choice;
 }
 
-/** Return the first non-open hop in cpath, or return NULL if all
- * hops are open. */
-static crypt_path_t *
-onion_next_hop_in_cpath(crypt_path_t *cpath)
-{
-  crypt_path_t *hop = cpath;
-  do {
-    if (hop->state != CPATH_STATE_OPEN)
-      return hop;
-    hop = hop->next;
-  } while (hop != cpath);
-  return NULL;
-}
-
 /** Choose a suitable next hop for the circuit <b>circ</b>.
  * Append the hop info to circ->cpath.
  *

src/core/or/circuitbuild.h

@@ -89,11 +89,6 @@ STATIC int
 onion_pick_cpath_exit(origin_circuit_t *circ, extend_info_t *exit_ei,
                       int is_hs_v3_rp_circuit);
 
-#if defined(TOR_UNIT_TESTS)
-unsigned int cpath_get_n_hops(crypt_path_t **head_ptr);
-
-#endif /* defined(TOR_UNIT_TESTS) */
-
 #endif /* defined(CIRCUITBUILD_PRIVATE) */
 
 #endif /* !defined(TOR_CIRCUITBUILD_H) */

src/core/or/crypt_path.c

@@ -210,3 +210,44 @@ cpath_set_cell_forward_digest(crypt_path_t *cpath, cell_t *cell)
   tor_assert(cpath->private);
   relay_set_digest(cpath->private->crypto.f_digest, cell);
 }
+
+/************ other cpath functions ***************************/
+
+/** Return the first non-open hop in cpath, or return NULL if all
+ * hops are open. */
+crypt_path_t *
+cpath_get_next_non_open_hop(crypt_path_t *cpath)
+{
+  crypt_path_t *hop = cpath;
+  do {
+    if (hop->state != CPATH_STATE_OPEN)
+      return hop;
+    hop = hop->next;
+  } while (hop != cpath);
+  return NULL;
+}
+
+#ifdef TOR_UNIT_TESTS
+
+/** Unittest helper function: Count number of hops in cpath linked list. */
+unsigned int
+cpath_get_n_hops(crypt_path_t **head_ptr)
+{
+  unsigned int n_hops = 0;
+  crypt_path_t *tmp;
+
+  if (!*head_ptr) {
+    return 0;
+  }
+
+  tmp = *head_ptr;
+  do {
+    n_hops++;
+    tmp = tmp->next;
+  } while (tmp != *head_ptr);
+
+  return n_hops;
+}
+
+#endif /* defined(TOR_UNIT_TESTS) */
+

src/core/or/crypt_path.h

@@ -32,4 +32,10 @@ cpath_get_incoming_digest(const crypt_path_t *cpath);
 void
 cpath_set_cell_forward_digest(crypt_path_t *cpath, cell_t *cell);
 
+crypt_path_t *cpath_get_next_non_open_hop(crypt_path_t *cpath);
+
+#if defined(TOR_UNIT_TESTS)
+unsigned int cpath_get_n_hops(crypt_path_t **head_ptr);
+#endif /* defined(TOR_UNIT_TESTS) */
+
 #endif