(svn r14345) -Fix: delete the RenameSignWindow when 'its' sign is deleted

Also, it makes sure the RenameSignWindow isn't open when there are no signs (and crashes associted with that)

src/signs.cpp

@@ -36,6 +36,10 @@ Sign::Sign(PlayerID owner)
 Sign::~Sign()
 {
 	free(this->name);
+
+	if (CleaningPool()) return;
+
+	DeleteRenameSignWindow(this->index);
 	this->owner = INVALID_PLAYER;
 }
 

src/signs_func.h

@@ -15,6 +15,7 @@ void PlaceProc_Sign(TileIndex tile);
 /* signs_gui.cpp */
 void ShowRenameSignWindow(const Sign *si);
 void HandleClickOnSign(const Sign *si);
+void DeleteRenameSignWindow(SignID sign);
 
 void ShowSignList();
 

src/signs_gui.cpp

@@ -286,8 +286,9 @@ struct SignWindow : QueryStringBaseWindow, SignList {
 
 			case QUERY_EDIT_SIGN_WIDGET_DELETE:
 				/* Only need to set the buffer to null, the rest is handled as the OK button */
-				DeleteTextBufferAll(&this->text);
-				/* FALL THROUGH */
+				RenameSign(this->cur_sign, "");
+				/* don't delete this, we are deleted in Sign::~Sign() -> DeleteRenameSignWindow() */
+				break;
 
 			case QUERY_EDIT_SIGN_WIDGET_OK:
 				RenameSign(this->cur_sign, this->text.buf);
@@ -358,3 +359,10 @@ void ShowRenameSignWindow(const Sign *si)
 
 	new SignWindow(&_query_sign_edit_desc, si);
 }
+
+void DeleteRenameSignWindow(SignID sign)
+{
+	SignWindow *w = dynamic_cast<SignWindow *>(FindWindowById(WC_QUERY_STRING, 0));
+
+	if (w != NULL && w->cur_sign == sign) delete w;
+}