net.dns: Avoid duplicate cache entries

diff --git a/net/dns.lua b/net/dns.lua
index 89bd3564b55b63982cd34b4135fb0bd77b478b73..dc2da1b608f3a29c33b1f22b0eeb175223bbd24e 100644 (file)
--- a/net/dns.lua
+++ b/net/dns.lua
@@ -134,17 +134,19 @@ end
 
 local function prune(rrs, time, soft)    -- - - - - - - - - - - - - - -  prune
        time = time or socket.gettime();
-       for i,rr in pairs(rrs) do
+       for i,rr in ipairs(rrs) do
                if rr.tod then
                        -- rr.tod = rr.tod - 50    -- accelerated decripitude
                        rr.ttl = math.floor(rr.tod - time);
                        if rr.ttl <= 0 then
+                               rrs[rr[rr.type:lower()]] = nil;
                                table.remove(rrs, i);
                                return prune(rrs, time, soft); -- Re-iterate
                        end
                elseif soft == 'soft' then    -- What is this?  I forget!
                        assert(rr.ttl == 0);
-                       rrs[i] = nil;
+                       rrs[rr[rr.type:lower()]] = nil;
+                       table.remove(rrs, i);
                end
        end
 end
@@ -187,7 +189,7 @@ end
 local rrs_metatable = {};    -- - - - - - - - - - - - - - - - - -  rrs_metatable
 function rrs_metatable.__tostring(rrs)
        local t = {};
-       for i,rr in pairs(rrs) do
+       for i,rr in ipairs(rrs) do
                append(t, tostring(rr)..'\n');
        end
        return table.concat(t);
@@ -674,7 +676,10 @@ function resolver:remember(rr, type)    -- - - - - - - - - - - - - -  remember
        self.cache = self.cache or setmetatable({}, cache_metatable);
        local rrs = get(self.cache, qclass, type, qname) or
                set(self.cache, qclass, type, qname, setmetatable({}, rrs_metatable));
-       append(rrs, rr);
+       if not rrs[rr[qtype:lower()]] then
+               rrs[rr[qtype:lower()]] = true;
+               append(rrs, rr);
+       end
 
        if type == 'MX' then self.unsorted[rrs] = true; end
 end