--- a/lib/update.updates	Tue Dec 17 01:17:49 2013 +0200
+++ b/lib/update.updates	Tue Dec 17 02:06:53 2013 +0200
@@ -10,7 +10,7 @@
 # Returns true if the output file needs to be updated.
 function check_update {
     # target
-    local out=$1; shift
+    local out="$1"; shift
 
     debug "$out"
 
@@ -21,7 +21,7 @@
         debug "  update: unknown deps"
         update=y
 
-    elif [ ! -e $out ]; then
+    elif [ ! -e "$out" ]; then
         debug "  update: dest missing"
         update=y
         
@@ -37,9 +37,9 @@
 
         # check
         if [ ! -e "$dep" ]; then
-            fail "$out: Missing source: $dep"
+            warn "$out: Missing source: $dep"
 
-        elif [ $out -ot "$dep" ]; then
+        elif [ "$out" -ot "$dep" ]; then
             debug "  update: $dep"
             update=y
         else
@@ -60,18 +60,18 @@
 # Writes output to a temporary .new file, optionally shows a diff of changes, and commits
 # the new version to $out (unless noop'd).
 function do_update {
-    local out=$1; shift
-    local tmp=$out.new
+    local out="$1"; shift
+    local tmp="$out.new"
 
     debug "$out"
-    cmd "$@" > $tmp
+    cmd "$@" > "$tmp"
 
     # compare
-    if [ -e $out ] && [ $UPDATE_DIFF ]; then
+    if [ -e "$out" ] && [ $UPDATE_DIFF ]; then
         debug "  changes:"
 
         # terse
-        indent "        " diff --unified=1 $out $tmp || true
+        indent "        " diff --unified=1 "$out" "$tmp" || true
     fi
     
     # deploy
@@ -79,33 +79,15 @@
         # cleanup
         debug "  no-op"
 
-        cmd rm $tmp
+        cmd rm "$tmp"
     else
         # commit
         debug "  deploy"
 
-        cmd mv $tmp $out
+        cmd mv "$tmp" "$out"
     fi
 }
 
-## Look for a link target:
-#
-#   find_link   $lnk    $tgt...
-#
-# Outputs the first given target to exist, skipping any that are the same as the given $lnk.
-# If no $tgt matches, outputs the last one, or '-'.
-function choose_link {
-    local lnk=$1; shift
-    local tgt=-
-
-    for tgt in "$@"; do
-        [ $tgt != $out ] && [ -e $tgt ] && break
-    done
-    
-    echo $tgt
-}
-
-
 ## Compare symlink to target:
 #
 #   check_link $lnk $tgt && do_link $lnk $tgt || ...
@@ -113,12 +95,12 @@
 # Tests if the symlink exists, and the target matches.
 # Fails if the target does not exist.
 function check_link {
-    local lnk=$1
-    local tgt=$2
+    local lnk="$1"
+    local tgt="$2"
 
-    [ ! -e $tgt ] && fail "$tgt: target does not exist"
+    [ ! -e "$tgt" ] && fail "$tgt: target does not exist"
     
-    [ ! -e $lnk ] || [ $(readlink $lnk) != $tgt ]
+    [ ! -e "$lnk" ] || [ $(readlink "$lnk") != "$tgt" ]
 }
 
 ## Update symlink to point to target:
@@ -126,9 +108,28 @@
 #   do_link $lnk $tgt
 #
 function do_link {
-    local lnk=$1
-    local tgt=$2
+    local lnk="$1"
+    local tgt="$2"
 
-    cmd ln -sf $tgt $lnk
+    cmd ln -sf "$tgt" "$lnk"
 }
 
+## Read include paths from file
+function read_zone_includes {
+    cmd sed -n -E 's/^\$INCLUDE\s+"(.+)"/\1/p' "$@"
+}
+
+## (cached) include paths for zone file
+function zone_includes {
+    local cache="$1"
+    local src="$2"
+    local dir="$3"
+
+    if [ ! -e "$cache" -o "$cache" -ot "$src" ]; then
+        read_zone_includes "$src" > "$cache"
+    fi
+
+    while read include; do
+        echo -n "$dir/$include "
+    done < "$cache"
+}