Merge branch 'jb/hotfix' into jb/fix

pkg/urbit/include/noun/events.h

@@ -84,9 +84,14 @@
       void
       u3e_foul(void);
 
-    /* u3e_init(): initialize page tracking.
+    /* u3e_init(): initialize guard page tracking.
     */
       void
       u3e_init(void);
 
+    /* u3e_ward(): reposition guard page if needed.
+    */
+      void
+      u3e_ward(u3_post low_p, u3_post hig_p);
+
 #endif /* ifndef U3_EVENTS_H */

pkg/urbit/noun/events.c

@@ -1097,6 +1097,8 @@ u3e_foul(void)
   memset((void*)u3P.dit_w, 0xff, sizeof(u3P.dit_w));
 }
 
+/* u3e_init(): initialize guard page tracking.
+*/
 void
 u3e_init(void)
 {
@@ -1104,3 +1106,15 @@ u3e_init(void)
   _ce_center_guard_page();
 #endif
 }
+
+/* u3e_ward(): reposition guard page if needed.
+*/
+void
+u3e_ward(u3_post low_p, u3_post hig_p)
+{
+#ifdef U3_GUARD_PAGE
+  if ( (low_p > gar_pag_p) || (hig_p < gar_pag_p) ) {
+    _ce_center_guard_page();
+  }
+#endif
+}

pkg/urbit/noun/manage.c

@@ -808,6 +808,7 @@ u3m_leap(c3_w pad_w)
       u3R->cap_p -= len_w;
 
       rod_u = _pave_south(u3a_into(bot_p), c3_wiseof(u3a_road), len_w);
+      u3e_ward(rod_u->cap_p, rod_u->hat_p);
 #if 0
       fprintf(stderr, "leap: from north %p (cap 0x%x), to south %p\r\n",
               u3R,
@@ -820,6 +821,7 @@ u3m_leap(c3_w pad_w)
       u3R->cap_p += len_w;
 
       rod_u = _pave_north(u3a_into(bot_p), c3_wiseof(u3a_road), len_w);
+      u3e_ward(rod_u->hat_p, rod_u->cap_p);
 #if 0
       fprintf(stderr, "leap: from south %p (cap 0x%x), to north %p\r\n",
               u3R,

pkg/urbit/tests/jam_tests.c

@@ -8,6 +8,7 @@ _setup(void)
 {
   u3m_init();
   u3m_pave(c3y);
+  u3e_init();
 }
 
 static void