From: Mark Wooding <mdw@distorted.org.uk>
Date: Tue, 13 Mar 2012 16:17:28 +0000 (+0000)
Subject: zoneconf: Awful kludge in `primary': masters never considered local.
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~mdw/git/zoneconf/commitdiff_plain/e4ce9d1ee876952c2c339a84ad658caff954a95e

zoneconf: Awful kludge in `primary': masters never considered local.

A master address containing `!' is never considered to be local:
the address to the left is used by remote hosts; the address to the
right is used by local ones.
---

diff --git a/zoneconf.in b/zoneconf.in
index 7af2845..4a6713f 100755
--- a/zoneconf.in
+++ b/zoneconf.in
@@ -1022,6 +1022,12 @@ define-configuration-space zone ZONECFG {
   }
 
   define primary {map} {
+    ## There's a grim hack here: a primary-address entry may have the form
+    ## REAL!FAKE.  If the REAL address is not a local address then this
+    ## is used as the master address; otherwise the FAKE address is used.
+    ## This is useful for inter-view updates of dynamic zones on the same
+    ## host.  I suggest abusing 127.0.0.0/8 addresses for this kind of
+    ## chicanery.
     if {[llength $map] % 2} {
       error "master map must have an even number of items"
     }
@@ -1141,13 +1147,24 @@ proc compute-zone-properties {view config} {
   if {[info exists zone(mapped-view)]} {
     foreach {outview hosts} $zone(master-map) {
       if {[string match $outview $zone(mapped-view)]} {
-	set zone(masters) $hosts
+	set masters {}
 	set zone(config-type) slave
 	foreach host $hosts {
-	  if {[local-address-p $host]} {
+	  set bang [string first "!" $host]
+	  if {$bang >= 0} {
+	    set before [string range $host 0 [expr {$bang - 1}]]
+	    set after [string range $host [expr {$bang + 1}] end]
+	    if {[local-address-p $before]} {
+	      set host $after
+	    } else {
+	      set host $before
+	    }
+	  } elseif {[local-address-p $host]} {
 	    set zone(config-type) master
 	  }
+	  lappend masters $host
 	}
+	set zone(masters) $masters
 	break
       }
     }