Use boost::asio::deadline_timer for walletpassphrase timeout
New method in bitcoinrpc: RunLater, that uses a map of deadline
timers to run a function later.
Behavior of walletpassphrase is changed; before, calling
walletpassphrase again before the lock timeout passed
would result in: Error: Wallet is already unlocked.
You would have to call lockwallet before walletpassphrase.
Now: the last walletpassphrase with correct password
wins, and overrides any previous timeout.
Fixes issue# 1961 which was caused by spawning too many threads.
Test plan:
Start with encrypted wallet, password 'foo'
Try:
walletpassphrase foo 600
getinfo
EXPECT: unlocked_until is about 10 minutes in the future
walletpassphrase foo 1
sleep 2
sendtoaddress mun74Bvba3B1PF2YkrF4NsgcJwHXXh12LF 11
EXPECT: Error: Please enter the wallet passphrase with walletpassphrase first.
walletpassphrase foo 600
walletpassphrase foo 0
getinfo
EXPECT: wallet is locked (unlocked_until is 0)
walletpassphrase foo 10
walletpassphrase foo 600
getinfo
EXPECT: wallet is unlocked until 10 minutes in future
walletpassphrase foo 60
walletpassphrase bar 600
EXPECT: Error, incorrect passphrase
getinfo
EXPECT: wallet still scheduled to lock 60 seconds from first (successful) walletpassphrase