[Freeciv-Dev] (PR#14983) rehoming fixes

["Jason Short" <jdorje@xxxxxxxxxxxxxxxxxxxxx>]

<URL: http://bugs.freeciv.org/Ticket/Display.html?id=14983 >

This patch cleans up and fixes rehoming behavior.  Previously 
can_unit_change_homecity was not called in most places so rehoming was 
erronously allowed even if the function would have returned false.

This applies to 2.0 also.

-jason

Index: server/unithand.c
===================================================================
--- server/unithand.c   (revision 11385)
+++ server/unithand.c   (working copy)
@@ -323,22 +323,11 @@
                                 int city_id)
 {
   struct unit *punit = player_find_unit_by_id(pplayer, unit_id);
-  struct city *new_pcity = player_find_city_by_id(pplayer, city_id);
+  struct city *pcity = player_find_city_by_id(pplayer, city_id);
 
-  if (!punit || !new_pcity || city_id == punit->homecity) {
-    return;
+  if (punit && pcity && can_unit_change_homecity_to(punit, pcity)) {
+    real_unit_change_homecity(punit, pcity);
   }
-  if (!same_pos(punit->tile, new_pcity->tile)) {
-    freelog(LOG_ERROR,
-            "%s's %s (%d) is at (%d,%d), but tried to make "
-           "%s at (%d,%d) its homecity.",
-            pplayer->name,
-            unit_name(punit->type), unit_id, punit->tile->x,
-            punit->tile->y, new_pcity->name, new_pcity->tile->x,
-            new_pcity->tile->y);
-    return;
-  }
-  real_unit_change_homecity(punit, new_pcity);
 }
 
 /**************************************************************************
Index: common/unit.c
===================================================================
--- common/unit.c       (revision 11385)
+++ common/unit.c       (working copy)
@@ -423,22 +423,34 @@
 }
 
 /**************************************************************************
-  Return TRUE iff the unit can change homecity at its current location.
+  Return TRUE iff the unit can change homecity to the given city.
 **************************************************************************/
-bool can_unit_change_homecity(const struct unit *punit)
+bool can_unit_change_homecity_to(const struct unit *punit,
+                                const struct city *pcity)
 {
   /* Requirements to change homecity:
    *
    * 1. Homeless cities can't change homecity (this is a feature since
    *    being homeless is a big benefit).
    * 2. The unit must be inside the city it is rehoming to.
-   * 3. Of course you can only have your own cities as homecity. */
-  return (punit->homecity != -1
+   * 3. Of course you can only have your own cities as homecity.
+   * 4. You can't rehome to the current homecity. */
+  return (punit && pcity
+         && punit->homecity > 0
          && punit->tile->city
-         && punit->tile->city->owner == punit->owner);
+         && punit->tile->city->owner == punit->owner
+         && punit->homecity != punit->tile->city->id);
 }
 
 /**************************************************************************
+  Return TRUE iff the unit can change homecity at its current location.
+**************************************************************************/
+bool can_unit_change_homecity(const struct unit *punit)
+{
+  return can_unit_change_homecity_to(punit, punit->tile->city);
+}
+
+/**************************************************************************
   Returns the speed of a unit doing an activity.  This depends on the
   veteran level and the base move_rate of the unit (regardless of HP or
   effects).  Usually this is just used for settlers but the value is also
Index: common/unit.h
===================================================================
--- common/unit.h       (revision 11385)
+++ common/unit.h       (working copy)
@@ -254,6 +254,8 @@
 bool can_unit_unload(const struct unit *punit, const struct unit *ptrans);
 bool can_unit_paradrop(const struct unit *punit);
 bool can_unit_bombard(const struct unit *punit);
+bool can_unit_change_homecity_to(const struct unit *punit,
+                                const struct city *pcity);
 bool can_unit_change_homecity(const struct unit *punit);
 const char *get_activity_text(enum unit_activity activity);
 bool can_unit_continue_current_activity(struct unit *punit);
Index: client/gui-gtk-2.0/citydlg.c
===================================================================
--- client/gui-gtk-2.0/citydlg.c        (revision 11385)
+++ client/gui-gtk-2.0/citydlg.c        (working copy)
@@ -2100,11 +2100,8 @@
       G_CALLBACK(unit_homecity_callback),
       GINT_TO_POINTER(punit->id));
     gtk_menu_shell_append(GTK_MENU_SHELL(menu), item);
+    gtk_widget_set_sensitive(item, can_unit_change_homecity_to(punit, pcity));
 
-    if (punit->homecity == pcity->id) {
-      gtk_widget_set_sensitive(item, FALSE);
-    }
-
     item = gtk_menu_item_new_with_mnemonic(_("U_pgrade unit"));
     g_signal_connect(item, "activate",
       G_CALLBACK(unit_upgrade_callback),

Index: server/unithand.c
===================================================================
--- server/unithand.c   (revision 11385)
+++ server/unithand.c   (working copy)
@@ -290,19 +290,10 @@
   struct city *old_pcity, *new_pcity =
       player_find_city_by_id(pplayer, city_id);
 
-  if (!punit || !new_pcity || city_id == punit->homecity) {
+  if (!punit || !new_pcity
+      || !can_unit_change_homecity_to(punit, new_pcity)) {
     return;
   }
-  if (!same_pos(punit->tile, new_pcity->tile)) {
-    freelog(LOG_ERROR,
-            "%s's %s (%d) is at (%d,%d), but tried to make "
-           "%s at (%d,%d) its homecity.",
-            pplayer->name,
-            unit_name(punit->type), unit_id, punit->tile->x,
-            punit->tile->y, new_pcity->name, new_pcity->tile->x,
-            new_pcity->tile->y);
-    return;
-  }
 
   old_pcity = player_find_city_by_id(pplayer, punit->homecity);
 
Index: common/unit.c
===================================================================
--- common/unit.c       (revision 11385)
+++ common/unit.c       (working copy)
@@ -503,18 +503,29 @@
 /**************************************************************************
 ...
 **************************************************************************/
-bool can_unit_change_homecity(struct unit *punit)
+bool can_unit_change_homecity_to(struct unit *punit, struct city *pcity)
 {
   /* Requirements to change homecity:
    *
    * 1. Homeless cities can't change homecity (this is a feature since
    *    being homeless is a big benefit).
    * 2. The unit must be inside the city it is rehoming to.
-   * 3. Of course you can only have your own cities as homecity. */
-  return (punit->homecity != -1
+   * 3. Of course you can only have your own cities as homecity.
+   * 4. You can't rehome to the current homecity. */
+  return (punit && pcity
+         && punit->homecity > 0
          && punit->tile->city
-         && punit->tile->city->owner == punit->owner);
+         && punit->tile->city->owner == punit->owner
+         && punit->homecity != punit->tile->city->id);
 }
+  
+/**************************************************************************
+  Return TRUE iff the unit can change homecity at its current location.
+**************************************************************************/
+bool can_unit_change_homecity(struct unit *punit)
+{
+  return can_unit_change_homecity_to(punit, punit->tile->city);
+}
 
 /**************************************************************************
   Returns the speed of a unit doing an activity.  This depends on the
Index: common/unit.h
===================================================================
--- common/unit.h       (revision 11385)
+++ common/unit.h       (working copy)
@@ -235,6 +235,7 @@
 bool can_unit_unload(struct unit *punit, struct unit *ptrans);
 bool can_unit_paradrop(struct unit *punit);
 bool can_unit_bombard(struct unit *punit);
+bool can_unit_change_homecity_to(struct unit *punit, struct city *pcity);
 bool can_unit_change_homecity(struct unit *punit);
 const char *get_activity_text(enum unit_activity activity);
 bool can_unit_continue_current_activity(struct unit *punit);
Index: client/gui-gtk-2.0/citydlg.c
===================================================================
--- client/gui-gtk-2.0/citydlg.c        (revision 11385)
+++ client/gui-gtk-2.0/citydlg.c        (working copy)
@@ -2001,11 +2001,8 @@
       G_CALLBACK(unit_homecity_callback),
       GINT_TO_POINTER(punit->id));
     gtk_menu_shell_append(GTK_MENU_SHELL(menu), item);
+    gtk_widget_set_sensitive(item, can_unit_change_homecity_to(punit, pcity));
 
-    if (punit->homecity == pcity->id) {
-      gtk_widget_set_sensitive(item, FALSE);
-    }
-
     item = gtk_menu_item_new_with_mnemonic(_("U_pgrade unit"));
     g_signal_connect(item, "activate",
       G_CALLBACK(unit_upgrade_callback),