From: Mark Wooding <mdw@distorted.org.uk>
Date: Sun, 3 Sep 2017 23:18:41 +0000 (+0100)
Subject: server/peer.c: Abstract out updating a peer's address.
X-Git-Tag: 1.5.0~91
X-Git-Url: https://git.distorted.org.uk/~mdw/tripe/commitdiff_plain/23bbe6014c89ed239b25405a8b7a8725413620f7

server/peer.c: Abstract out updating a peer's address.
---

diff --git a/server/peer.c b/server/peer.c
index 891888b0..03ed2ae3 100644
--- a/server/peer.c
+++ b/server/peer.c
@@ -166,6 +166,51 @@ static int p_encrypt(peer *p, int ty, buf *bin, buf *bout)
   return (err);
 }
 
+/* --- @p_updateaddr@ --- *
+ *
+ * Arguments:	@peer *p@ = pointer to peer block
+ *		@const addr *a@ = address to associate with this peer
+ *
+ * Returns:	Zero if the address was changed; @+1@ if it was already
+ *		right.
+ *
+ * Use:		Updates our idea of @p@'s address.
+ */
+
+int p_updateaddr(peer *p, const addr *a)
+{
+  peer *q;
+  peer_byaddr *pa, *qa;
+  unsigned f;
+
+  /* --- Figure out how to proceed --- *
+   *
+   * If this address already belongs to a different peer, then swap the
+   * addresses over.  This doesn't leave the displaced peer in an especially
+   * good state, but it ought to get sorted out soon enough.
+   */
+
+  pa = am_find(&byaddr, a, sizeof(peer_byaddr), &f);
+  if (f && pa->p == p)
+    return (+1);
+  else if (!f) {
+    T( trace(T_PEER, "peer: updating address for `%s'", p_name(p)); )
+    am_remove(&byaddr, p->byaddr);
+    p->byaddr = pa; p->spec.sa = *a; pa->p = p;
+    a_notify("NEWADDR", "?PEER", p, "?ADDR", a, A_END);
+    return (0);
+  } else {
+    q = pa->p; qa = p->byaddr;
+    T( trace(T_PEER, "peer: swapping addresses for `%s' and `%s'",
+	     p_name(p), p_name(q)); )
+    q->byaddr = qa; qa->p = q; q->spec.sa = p->spec.sa;
+    p->byaddr = pa; pa->p = p; p->spec.sa = *a;
+    a_notify("NEWADDR", "?PEER", p, "?ADDR", a, A_END);
+    a_notify("NEWADDR", "?PEER", q, "?ADDR", &q->spec.sa, A_END);
+    return (0);
+  }
+}
+
 /* --- @p_decrypt@ --- *
  *
  * Arguments:	@peer **pp@ = pointer to peer to decrypt message from
@@ -188,9 +233,7 @@ static int p_decrypt(peer **pp, addr *a, size_t n,
 		     int ty, buf *bin, buf *bout)
 {
   peer *p, *q;
-  peer_byaddr *pa, *qa;
   int err = KSERR_DECRYPT;
-  unsigned f;
 
   /* --- If we have a match on the source address then try that first --- */
 
@@ -248,33 +291,11 @@ searched:
     return (-1);
   }
 
-  /* --- We found one that accepted, so update the peer's address --- *
-   *
-   * If we had an initial guess of which peer this packet came from -- i.e.,
-   * @q@ is not null -- then swap the addresses over.  This doesn't leave the
-   * evicted peer in an especially good state, but it ought to get sorted out
-   * soon enough.
-   */
+  /* --- We found one that accepted, so update the peer's address --- */
 
   if (!err) {
     *pp = p;
-    if (!q) {
-      T( trace(T_PEER, "peer: updating address for `%s'", p_name(p)); )
-      pa = am_find(&byaddr, a, sizeof(peer_byaddr), &f); assert(!f);
-      am_remove(&byaddr, p->byaddr);
-      p->byaddr = pa;
-      pa->p = p;
-      p->spec.sa = *a;
-      a_notify("NEWADDR", "?PEER", p, "?ADDR", a, A_END);
-    } else {
-      T( trace(T_PEER, "peer: swapping addresses for `%s' and `%s'",
-	       p_name(p), p_name(q)); )
-      pa = p->byaddr; qa = q->byaddr;
-      pa->p = q; q->byaddr = pa; q->spec.sa = p->spec.sa;
-      qa->p = p; p->byaddr = qa; p->spec.sa = *a;
-      a_notify("NEWADDR", "?PEER", p, "?ADDR", a, A_END);
-      a_notify("NEWADDR", "?PEER", q, "?ADDR", &q->spec.sa, A_END);
-    }
+    p_updateaddr(p, a);
   }
 
 match:
diff --git a/server/tripe.h b/server/tripe.h
index fa5333bd..e7c47ecd 100644
--- a/server/tripe.h
+++ b/server/tripe.h
@@ -1409,6 +1409,19 @@ extern void ps_quit(void);
 
 /*----- Peer management ---------------------------------------------------*/
 
+/* --- @p_updateaddr@ --- *
+ *
+ * Arguments:	@peer *p@ = pointer to peer block
+ *		@const addr *a@ = address to associate with this peer
+ *
+ * Returns:	Zero if the address was changed; @+1@ if it was already
+ *		right.
+ *
+ * Use:		Updates our idea of @p@'s address.
+ */
+
+extern int p_updateaddr(peer */*p*/, const addr */*a*/);
+
 /* --- @p_txstart@ --- *
  *
  * Arguments:	@peer *p@ = pointer to peer block