[FIXED] Custom fs.open: java.lang.ArrayIndexOutOfBoundsException: 256

11: vm error: java.lang.ArrayIndexOutOfBoundsException: 256

11: stack overflow

-- indenting doesn't work on the post editor :/
oldfs = fs
newfs = {}
function newfs.open(file,method)
if method == 'r' then
download(file)
end
oldHandle = oldfs.open(file,method)
newHandle = oldHandle
if method == 'w' or method == 'a' then
function newHandle.close()
oldHandle.close()
upload(file)
end
end
return newHandle
end
local h = newfs.open('test','w')
h.write('test')
h.close()

local oldClose = handle.close

function handle.close()
  oldClose()
  etc...

Bomb Bloke, on 15 May 2016 - 08:09 AM said:

Remember that you can't assign tables to variables - you're instead assigning pointers which lead to tables. Same goes for functions and coroutines.

So because "newHandle" and "oldHandle" each point to the same table, when you tell newHandle.close() to call oldHandle.close(), you're really telling the function to call itself. The resulting infinite loop of calls blows up the function stack - this causes a Java error within LuaJ, and a similar error message from Mimic.

If you want to create a new table with the same content as an existing one, you'll need to specifically make a new table and copy that content over.

Alternatively, you could just preserve your old close() pointer in a local variable:

local oldClose = handle.close

function handle.close()
  oldClose()
  etc...