[or-cvs] Make sequential ACI selection logic handle HIGHER/LOWER

[Nick Mathewson]

Update of /home/or/cvsroot/src/or
In directory moria.mit.edu:/tmp/cvs-serv10562/or

Modified Files:
	circuit.c or.h 
Log Message:
Make sequential ACI selection logic handle HIGHER/LOWER

Index: circuit.c
===================================================================
RCS file: /home/or/cvsroot/src/or/circuit.c,v
retrieving revision 1.63
retrieving revision 1.64
diff -u -d -r1.63 -r1.64
--- circuit.c	16 Sep 2003 19:36:19 -0000	1.63
+++ circuit.c	16 Sep 2003 20:13:43 -0000	1.64
@@ -123,17 +123,23 @@
   connection_t *conn;
 
 #ifdef SEQUENTIAL_ACI
-  /* Right now, this is the only used aci_type.  XXX The others should
-     be removed. */
-  assert(aci_type == ACI_TYPE_BOTH); 
+  uint16_t high_bit;
+  high_bit = (aci_type == ACI_TYPE_HIGHER) ? 1<<15 : 0;
   conn = connection_exact_get_by_addr_port(addr,port);
   if (!conn)
     return 1; /* No connection exists; conflict is impossible. */
+
   do {
-    test_aci = conn->next_aci++; /* This can wrap around to 0; that's okay. */
-    if (test_aci == 0)
-      continue;
+    /* Sequentially iterate over test_aci=1...1<<15-1 until we find an
+     * aci such that (high_bit|test_aci) is not already used. */
+    test_aci = conn->next_aci++;
+    if (test_aci == 0 || test_aci >= 1<<15) {
+      test_aci = 1;
+      conn->next_aci = 2;
+    }
+    test_aci |= high_bit;
   } while(circuit_get_by_aci_conn(test_aci, conn));
+  return test_aci;
 #else
 try_again:
   log_fn(LOG_DEBUG,"trying to get a unique aci");

Index: or.h
===================================================================
RCS file: /home/or/cvsroot/src/or/or.h,v
retrieving revision 1.128
retrieving revision 1.129
diff -u -d -r1.128 -r1.129
--- or.h	16 Sep 2003 19:36:19 -0000	1.128
+++ or.h	16 Sep 2003 20:13:43 -0000	1.129
@@ -330,7 +330,8 @@
   char nonce[8];
 #endif
 #ifdef SEQUENTIAL_ACI
-  uint16_t next_aci; /* Which ACI do we try to use next on this connection? */
+  uint16_t next_aci; /* Which ACI do we try to use next on this connection? 
+                      * This is always in the range 0..1<<15-1.*/
 #endif
 
 /* Used only by edge connections: */