Give names to units

The name is empty by default, but can be set by sending unit_rename packets. It
is limited to MAX_LEN_NAME which is 48 bytes including the terminating zero.

Requested by jwrober in longturn#281.

client/packhand.cpp

@@ -194,6 +194,8 @@ static struct unit *unpackage_unit(const struct packet_unit_info *packet)
   unit_tile_set(punit, index_to_tile(&(wld.map), packet->tile));
   punit->facing = packet->facing;
   punit->homecity = packet->homecity;
+  punit->name = QString::fromUtf8(QByteArray(packet->name,
+                                             ARRAY_SIZE(packet->name)));
   output_type_iterate(o) { punit->upkeep[o] = packet->upkeep[o]; }
   output_type_iterate_end;
   punit->moves_left = packet->movesleft;
@@ -290,6 +292,7 @@ unpackage_short_unit(const struct packet_unit_short_info *packet)
   punit->veteran = packet->veteran;
   punit->hp = packet->hp;
   punit->activity = static_cast<unit_activity>(packet->activity);
+  punit->name = QString::fromUtf8(packet->name, ARRAY_SIZE(packet->name));
 
   if (packet->activity_tgt == EXTRA_NONE) {
     punit->activity_target = NULL;

common/networking/packets.def

@@ -1040,6 +1040,7 @@ PACKET_UNIT_INFO = 63; sc, lsend, is-game-info, cancel(PACKET_UNIT_SHORT_INFO)
   EXTRA changed_from_tgt;
 
   SINT8 battlegroup;
+  STRING name[MAX_LEN_NAME];
 
   BOOL has_orders;
   UINT16 orders_length, orders_index;
@@ -1059,6 +1060,7 @@ PACKET_UNIT_SHORT_INFO = 64; sc, lsend, is-game-info, force, cancel(PACKET_UNIT_
 
   UINT8 veteran;
   BOOL occupied, transported;
+  STRING name[MAX_LEN_NAME];
 
   UINT8 hp, activity;
   EXTRA activity_tgt;
@@ -1152,6 +1154,11 @@ PACKET_UNIT_ACTIONS = 90; sc, dsend
   ACT_PROB action_probabilities[MAX_NUM_ACTIONS];
 end
 
+PACKET_UNIT_RENAME = 91; cs, dsend
+  UNIT unit_id;
+  STRING name[MAX_LEN_NAME];
+end
+
 PACKET_UNIT_CHANGE_ACTIVITY = 222; cs, dsend
   UNIT unit_id;
   ACTIVITY activity;

common/unit.h

@@ -127,6 +127,7 @@ struct unit {
   struct player *nationality;
   int id;
   int homecity;
+  QString name;
 
   int upkeep[O_LAST]; // unit upkeep with regards to the homecity
 

server/unithand.cpp

@@ -1940,6 +1940,19 @@ void handle_unit_get_actions(struct connection *pc, const int actor_unit_id,
   }
 }
 
+/**
+ * Handle request to rename a unit.
+ */
+void handle_unit_rename(player *pplayer, int unit_id, const char *name)
+{
+  auto unit = game_unit_by_number(unit_id);
+  fc_assert_ret(unit != nullptr);
+  fc_assert_ret(pplayer == unit->owner);
+
+  // Use the QByteArray overload to prevent unbounded read
+  unit->name = QString::fromUtf8(name, MAX_LEN_NAME);
+}
+
 /**
    Try to explain to the player why an action is illegal.
 

server/unittools.cpp

@@ -2539,6 +2539,7 @@ void package_unit(struct unit *punit, struct packet_unit_info *packet)
   packet->tile = tile_index(unit_tile(punit));
   packet->facing = punit->facing;
   packet->homecity = punit->homecity;
+  fc_strlcpy(packet->name, punit->name.toUtf8(), ARRAY_SIZE(packet->name));
   output_type_iterate(o) { packet->upkeep[o] = punit->upkeep[o]; }
   output_type_iterate_end;
   packet->veteran = punit->veteran;
@@ -2624,6 +2625,7 @@ void package_short_unit(struct unit *punit,
   packet->type = utype_number(unit_type_get(punit));
   packet->hp = punit->hp;
   packet->occupied = (get_transporter_occupancy(punit) > 0);
+  fc_strlcpy(packet->name, punit->name.toUtf8(), ARRAY_SIZE(packet->name));
   if (punit->activity == ACTIVITY_EXPLORE
       || punit->activity == ACTIVITY_GOTO) {
     packet->activity = ACTIVITY_IDLE;