Fixup tor_addr_to_sockaddr return convention

src/common/address.c

@@ -50,11 +50,13 @@
 #include <assert.h>
 
 /** Convert the tor_addr_t in <b>a</b>, with port in <b>port</b>, into a
- * socklen object in *<b>sa_out</b> of object size <b>len</b>.  If not enough
- * room is free, or on error, return -1.  Else return the length of the
- * sockaddr. */
-/* XXXX021 This returns socklen_t.  socklen_t is sometimes unsigned.  This
- *   function claims to return -1 sometimes.  Problematic! */
+ * sockaddr object in *<b>sa_out</b> of object size <b>len</b>.  If not enough
+ * room is available in sa_out, or on error, return 0  On success, return
+ * the length of the sockaddr.
+ *
+ * Interface note: ordinarly, we return -1 for error.  We can't do that here,
+ * since socklen is unsigned on some platforms.
+ **/
 socklen_t
 tor_addr_to_sockaddr(const tor_addr_t *a,
                      uint16_t port,
@@ -65,7 +67,7 @@ tor_addr_to_sockaddr(const tor_addr_t *a,
   if (family == AF_INET) {
     struct sockaddr_in *sin;
     if (len < (int)sizeof(struct sockaddr_in))
-      return -1;
+      return 0;
     sin = (struct sockaddr_in *)sa_out;
     memset(sin, 0, sizeof(struct sockaddr_in));
 #ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
@@ -78,7 +80,7 @@ tor_addr_to_sockaddr(const tor_addr_t *a,
   } else if (family == AF_INET6) {
     struct sockaddr_in6 *sin6;
     if (len < (int)sizeof(struct sockaddr_in6))
-      return -1;
+      return 0;
     sin6 = (struct sockaddr_in6 *)sa_out;
     memset(sin6, 0, sizeof(struct sockaddr_in6));
 #ifdef HAVE_STRUCT_SOCKADDR_IN6_SIN6_LEN
@@ -89,7 +91,7 @@ tor_addr_to_sockaddr(const tor_addr_t *a,
     memcpy(&sin6->sin6_addr, tor_addr_to_in6(a), sizeof(struct in6_addr));
     return sizeof(struct sockaddr_in6);
   } else {
-    return -1;
+    return 0;
   }
 }
 

src/or/dns.c

@@ -1206,7 +1206,7 @@ configure_nameservers(int force)
       struct sockaddr_storage ss;
       socklen = tor_addr_to_sockaddr(&addr, 0,
                                      (struct sockaddr *)&ss, sizeof(ss));
-      if (socklen < 0) {
+      if (socklen <= 0) {
         log_warn(LD_BUG, "Couldn't convert outbound bind address to sockaddr."
                  " Ignoring.");
       } else {