Freeciv

that turns out to be illegal. Only applied when the player wasn't aware that

the action was illegal and its illegality therefore reveals new information.

  Punish a player for trying to perform an action that turned out to be

  illegal. The punishment, if any at all, is specified by the ruleset.

  @param pplayer the player to punish.

  @param information_revealed if finding out that the action is illegal

                              reveals new information.

  @param act_unit the actor unit performing the action.

  @param stopped_action the illegal action.

  @param tgt_player the intended target of the action.

  @param requester who ordered the action performed?

  @return TRUE iff player was punished for trying to do the illegal action.

static bool illegal_action_pay_price(struct player *pplayer,

                                     bool information_revealed,

                                     struct unit *act_unit,

                                     struct action *stopped_action,

                                     struct player *tgt_player,

                                     const enum action_requester requester)

  fc_assert_ret_val_msg((requester == ACT_REQ_PLAYER

                         || requester == ACT_REQ_SS_AGENT),

                        FALSE,

                        "The player wasn't responsible for this.");

  if (!information_revealed) {

    /* The player already had enough information to determine that this

     * action is illegal. Don't punish a client error or an accident. */

    return FALSE;

  }

                                           unit_owner(act_unit),

                                           act_unit,

                                           unit_type_get(act_unit),

                                           stopped_action,

  /* Stay in range */

  punishment_mp = MAX(0, punishment_mp);

  /* Punish the unit's move fragments. */

  act_unit->moves_left = MAX(0, act_unit->moves_left - punishment_mp);

  send_unit_info(NULL, act_unit);

  if (punishment_mp != 0) {

    notify_player(pplayer, unit_tile(act_unit),

                  unit_name_translation(act_unit),

  return punishment_mp != 0;

}

/**********************************************************************//**

  Tell the client that the action it requested is illegal. This can be

  caused by the player (and therefore the client) not knowing that some

  condition of an action no longer is true.

**************************************************************************/

static void illegal_action(struct player *pplayer,

                           struct unit *actor,

                           action_id stopped_action_id,

                           struct player *tgt_player,

                           const struct tile *target_tile,

                           const struct city *target_city,

                           const struct unit *target_unit,

                           bool disturb_player,

                           const enum action_requester requester)

{

  bool information_revealed;

  bool was_punished;

  struct action *stopped_action = action_by_number(stopped_action_id);

  /* Why didn't the game check before trying something illegal? Did a good

   * reason to not call is_action_enabled_unit_on...() appear? The game is

   * omniscient... */

  fc_assert(requester != ACT_REQ_RULES);

  information_revealed = action_prob_possible(action_prob_unit_vs_tgt(

                                                 stopped_action,

                                                 actor,

                                                 target_city, target_unit,

                                                 target_tile, NULL));

  was_punished = illegal_action_pay_price(pplayer, information_revealed,

                                          actor, stopped_action, tgt_player,

                                          requester);

  if (disturb_player || was_punished) {

    illegal_action_msg(pplayer, (information_revealed

                                 ? E_UNIT_ILLEGAL_ACTION : E_BAD_COMMAND),

                       actor, stopped_action_id,