Two-player TicTacToe winner-takes-all with EOS stakes via smart contract.

The smart contract has three actions:

• newgame(player1, player2, stake): Creates a new game between player1 and player2 for a defined stake. Each player automatically transfers this emount to the contract to keep. On a draw, both players get back their stakes. If a winner is found then that player gets double the initial stake.
• endgame(player1, player2): Ends game and removes entries from table. If game is not finished then players get their stakes back, but only if no moves have been made.
• play(player1, player2, row, col): Current player takes turn at row and column position.

EOSIO is expected to be compiled and available on the system, especially eosiocpp:

% make
eosiocpp -o TicTacToe.wast TicTacToe.cpp
eosiocpp -g TicTacToe.abi TicTacToe.cpp
Generated TicTacToe.abi ...

In order for the smart contract to function, the blockchain it is uploaded to must also have the eosio.token contract in order to be able to transfer stakes to winning players from the losers.

Additionally, all attending players must set permission eosio.code for this smart contract. If this contract is uploaded to account tictactoe and user wants to set the permission:

% cleos set account permission user active \
'{"threshold": 1,
  "keys": [{
    "key": "PUBKEY_OF_user",
    "weight": 1
  }],
  "accounts": [{
    "permission": {"actor": "tictactoe",
                   "permission": "eosio.code"},
                   "weight": 1
  }]}' owner -p user