a lock server

hi guys, what i want:

two new commands that manage membase key-value values (using a new memcached function)

at server side:

=================

1)LOCK key value <timeout>

find 'key'

if not found{

    create key with value

    if can´t create key{

        return ERROR

    }

    set key as founded

}

if founded {

    return current key value

}

return ERROR

=================

2)UNLOCK key value

find 'key'

if timedout{

    delete

    return ERROR

}

if not found {

    return ERROR

}

if value = sent value{

    delete key

    return sent value

}

return current key value

=================

at client side:

string memcache_lock(string key,string value,integer/float timeout);

if lock ok will return value, if not will return another value (key value or error)

string memcache_unlock(string key, string value);

if unlock ok will return value, if not will return another value (key value or error)

=================

that´s all

with this 'I' can make a lock system =] without ddlockd or another very complex lock server, i don´t nned another client library just memcached

i´m using PIC18f4550 to make a memcache protocol, i´m implementing lock at PIC code, but it´s very big and consuming a lot of ROM/RAM/CPU/network, could we implement it at server side?

thanks