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authorFulup Ar Foll <fulup@iot.bzh>2017-08-20 17:16:28 +0200
committerFulup Ar Foll <fulup@iot.bzh>2017-08-20 17:16:28 +0200
commitd51d083be8e34000cd00ce979445eacb45a16e97 (patch)
treef049458d72b7c6ebe7bea10770f48db1adfc0646 /conf.d/project/lua.d/onload-aaaa-00-utils.lua
parentc58b7ea33694ab8c76f8cb452d3b8928eb3279ad (diff)
Updated to latest App Template
Diffstat (limited to 'conf.d/project/lua.d/onload-aaaa-00-utils.lua')
-rw-r--r--conf.d/project/lua.d/onload-aaaa-00-utils.lua86
1 files changed, 86 insertions, 0 deletions
diff --git a/conf.d/project/lua.d/onload-aaaa-00-utils.lua b/conf.d/project/lua.d/onload-aaaa-00-utils.lua
new file mode 100644
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@@ -0,0 +1,86 @@
+--[[
+ Copyright (C) 2016 "IoT.bzh"
+ Author Fulup Ar Foll <fulup@iot.bzh>
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+ Note: this file should be called before any other to assert declare function
+ is loaded before anything else.
+
+ References:
+ http://lua-users.org/wiki/DetectingUndefinedVariables
+
+--]]
+
+
+--===================================================
+--= Niklas Frykholm
+-- basically if user tries to create global variable
+-- the system will not let them!!
+-- call GLOBAL_lock(_G)
+--
+--===================================================
+function GLOBAL_lock(t)
+ local mt = getmetatable(t) or {}
+ mt.__newindex = lock_new_index
+ setmetatable(t, mt)
+end
+
+--===================================================
+-- call GLOBAL_unlock(_G)
+-- to change things back to normal.
+--===================================================
+function GLOBAL_unlock(t)
+ local mt = getmetatable(t) or {}
+ mt.__newindex = unlock_new_index
+ setmetatable(t, mt)
+end
+
+function lock_new_index(t, k, v)
+ if (string.sub(k,1,1) ~= "_") then
+ GLOBAL_unlock(_G)
+ error("GLOBALS are locked -- " .. k ..
+ " must be declared local or prefix with '_' for globals.", 2)
+ else
+ rawset(t, k, v)
+ end
+end
+
+function unlock_new_index(t, k, v)
+ rawset(t, k, v)
+end
+
+-- return serialised version of printable table
+function Dump_Table(o)
+ if type(o) == 'table' then
+ local s = '{ '
+ for k,v in pairs(o) do
+ if type(k) ~= 'number' then k = '"'..k..'"' end
+ s = s .. '['..k..'] = ' .. Dump_Table(v) .. ','
+ end
+ return s .. '} '
+ else
+ return tostring(o)
+ end
+end
+
+
+-- simulate C prinf function
+printf = function(s,...)
+ io.write(s:format(...))
+ io.write("\n")
+ return
+end
+
+-- lock global variable
+GLOBAL_lock(_G)