I need to implement a sleep logic in a loop

i need to check for SELECT/INSERT stm if it s locked by other user i will go to sleep mode then back to earlier savepoint position

eg

savepoint x;

INSERT/SELECT

i need to check for 10 times each time sleep is for 1 sec

i applied counter i tried the logic

WHILE g_savepoint_loop <= 3
LOOP
g_sleep := ’1′ ;
g_sleep := g_sleep_in_sec + 1 ;
END LOOP;
ROLLBACK TO x ;

By query here is how to declare g_sleep to 1 sec(datatype ??) ,my logic says wrong type

please guide me