fix(ARM) workaround for LuaJIT/ARM bug

fixes #93

README.md

@@ -51,6 +51,11 @@ Release process:
 4. commit and tag the release
 5. upload rock to LuaRocks
 
+### 5.0.x (unreleased)
+
+- Fix: workaround for LuaJIT/ARM bug, see [Issue 93](https://github.com/Kong/lua-resty-dns-client/issues/93).
+
+
 ### 5.0.0 (14-May-2020)
 
 - BREAKING: `getPeer` now returns the host-header value instead of the hostname
@@ -59,7 +64,7 @@ Release process:
   ip-address as the hostname, but will now return `nil`. See
   [PR 89](https://github.com/Kong/lua-resty-dns-client/pull/89).
 - Added: option `useSRVname`, if truthy then `getPeer` will return the name as found
-  in the SRV record, instead of the hostname as added to the balancer. 
+  in the SRV record, instead of the hostname as added to the balancer.
   See [PR 89](https://github.com/Kong/lua-resty-dns-client/pull/89).
 - Added: callback return an extra parameter; the host-header for the address added/removed.
 - Fix: using the module instance instead of the passed one for dns resolution

src/resty/dns/balancer/ring.lua

@@ -103,6 +103,7 @@ function ring_address:addIndices(availableIndicesList, count)
   return self
 end
 
+
 -- Drop an amount of indices and return them to the overall balancer.
 -- @param availableIndicesList The list to add the dropped indices to
 -- @param count (optional) The number of indices to drop, defaults to ALL if omitted
@@ -133,7 +134,14 @@ function ring_address:dropIndices(availableIndicesList, count)
       -- table was reduced by at least half, so drop the original to reduce
       -- memory footprint
       self.indicesMax = size
+      --[[ next line disabled due to LuaJIT/ARM issue, see https://github.com/Kong/lua-resty-dns-client/issues/93
       self.indices = table.move(self.indices, 1, size, 1, {})
+      Below a pure-Lua implementation --]]
+      local replacement = {}
+      for i = 1, size do
+        replacement[i] = self.indices[i]
+      end
+      self.indices = replacement
     end
   end
   return availableIndicesList