New DelKey.lua, and initial smax / dsm function libs

lua/DelKey.lua

@@ -0,0 +1,44 @@
+-- keys: [1+] SMA-X keywords
+-- arguments: (none)
+-- returns: (integer) the total number of fields deleted, including in sub-structures, and in parent structures.
+
+local metas = { '<timestamps>', '<types>', '<dims>', '<origins>', '<writes>', '<reads>', '<descriptions>', '<units>', '<coords>' }
+local n = 0
+
+local function DelKey (table)
+  -- Recursively delete table entries
+  for f in redis.call('hkeys', table) do
+    DelKey(table..':'..field) 
+  end
+
+  -- Delete metadata for the table
+  for m in metas do
+    redis.call("hdel", m, table)
+  end
+
+  -- Delete the table itself
+  if redis.call('del', table) == 1 then
+    n = n + 1
+  end
+end
+
+-- Process each input keyword
+for key in KEYS do
+  -- Delete the table (if any) recuresively
+  DelKey(key)
+
+  -- match the substring starting with the last :
+  local tail = key:gmatch(':(?:.(?!:))+')
+
+  -- If the keyword can be split...
+  if tail ~= nil and tail ~= '' then
+    -- Delete reference from parent table
+    local parent = table:sub(1, -tail:len())
+    local ref = tail:sub(2)
+    if redis.call('hdel', parent, ref) == 1 then
+      n = n + 1
+    end
+  end
+end
+
+return n

lua/dsm.lib

@@ -0,0 +1,32 @@
+#!lua name=dsm
+
+local function dsm_get_key(KEYS, ARGS)
+ -- keys: <none>
+ -- arguments: host target key
+ -- returns name SMA-X table name under which the data can be found
+
+ local table = "DSM:"..ARGV[2]
+ local key = ARGV[3]
+
+ -- If the data is stored under the target name, use that
+ if redis.call('hexists', table, key) == 1 then
+   return table
+ end
+
+ -- If the data is stored under the caller's name, use that
+ table = "DSM:"..ARGV[1]
+ if redis.call('hexists', table, key) == 1 then
+   return table
+ end
+
+ -- LUA false maps to Redis nil
+ return false
+end
+
+
+redis.register_function {
+ function_name='dsm_het_key', 
+ callback=dsm_get_key,
+ flags={ 'no-writes' },
+ description='(|host, target, key) Returns the SMA-X table for the given host and target machine and DSM key'
+}