Code to parse and access network parameters.

Partial backport of 381766ce4b1145460.
Partial backport of 56c6d78520a98fb64.

1 files changed, 31 insertions, 0 deletions

diff --git a/src/or/networkstatus.c b/src/or/networkstatus.c
index 573197a53f..05da73b5cb 100644
--- a/src/or/networkstatus.c
+++ b/src/or/networkstatus.c
@@ -286,6 +286,10 @@ networkstatus_vote_free(networkstatus_t *ns)
     SMARTLIST_FOREACH(ns->known_flags, char *, c, tor_free(c));
     smartlist_free(ns->known_flags);
   }
+  if (ns->net_params) {
+    SMARTLIST_FOREACH(ns->net_params, char *, c, tor_free(c));
+    smartlist_free(ns->net_params);
+  }
   if (ns->supported_methods) {
     SMARTLIST_FOREACH(ns->supported_methods, char *, c, tor_free(c));
     smartlist_free(ns->supported_methods);
@@ -1884,6 +1888,33 @@ networkstatus_dump_bridge_status_to_file(time_t now)
   tor_free(status);
 }
 
+/** Return the value of a integer parameter from the networkstatus <b>ns</b>
+ * whose name is <b>param_name</b>.  Return <b>default_val</b> if ns is NULL,
+ * or if it has no parameter called <b>param_name</b>. */
+int32_t
+networkstatus_get_param(networkstatus_t *ns, const char *param_name,
+                        int32_t default_val)
+{
+  size_t name_len;
+
+  if (!ns || !ns->net_params)
+    return default_val;
+
+  name_len = strlen(param_name);
+
+  SMARTLIST_FOREACH_BEGIN(ns->net_params, const char *, p) {
+    if (!strcmpstart(p, param_name) && p[name_len] == '=') {
+      int ok=0;
+      long v = tor_parse_long(p+name_len+1, 10, INT32_MIN, INT32_MAX, &ok,
+                              NULL);
+      if (ok)
+        return (int32_t) v;
+    }
+  } SMARTLIST_FOREACH_END(p);
+
+  return default_val;
+}
+
 /** If <b>question</b> is a string beginning with "ns/" in a format the
  * control interface expects for a GETINFO question, set *<b>answer</b> to a
  * newly-allocated string containing networkstatus lines for the appropriate