src/rollback_interface.cpp

   1 /*
   2 Minetest
   3 Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>
   4
   5 This program is free software; you can redistribute it and/or modify
   6 it under the terms of the GNU Lesser General Public License as published by
   7 the Free Software Foundation; either version 2.1 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU Lesser General Public License for more details.
  14
  15 You should have received a copy of the GNU Lesser General Public License along
  16 with this program; if not, write to the Free Software Foundation, Inc.,
  17 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18 */
  19
  20 #include "rollback_interface.h"
  21 #include <sstream>
  22 #include "util/serialize.h"
  23 #include "util/string.h"
  24 #include "util/numeric.h"
  25 #include "util/basic_macros.h"
  26 #include "map.h"
  27 #include "gamedef.h"
  28 #include "nodedef.h"
  29 #include "nodemetadata.h"
  30 #include "exceptions.h"
  31 #include "log.h"
  32 #include "inventorymanager.h"
  33 #include "inventory.h"
  34 #include "mapblock.h"
  35
  36
  37 RollbackNode::RollbackNode(Map *map, v3s16 p, IGameDef *gamedef)
  38 {
  39         const NodeDefManager *ndef = gamedef->ndef();
  40         MapNode n = map->getNode(p);
  41         name = ndef->get(n).name;
  42         param1 = n.param1;
  43         param2 = n.param2;
  44         NodeMetadata *metap = map->getNodeMetadata(p);
  45         if (metap) {
  46                 std::ostringstream os(std::ios::binary);
  47                 metap->serialize(os, 1); // FIXME: version bump??
  48                 meta = os.str();
  49         }
  50 }
  51
  52
  53 std::string RollbackAction::toString() const
  54 {
  55         std::ostringstream os(std::ios::binary);
  56         switch (type) {
  57         case TYPE_SET_NODE:
  58                 os << "set_node " << PP(p);
  59                 os << ": (" << serializeJsonString(n_old.name);
  60                 os << ", " << itos(n_old.param1);
  61                 os << ", " << itos(n_old.param2);
  62                 os << ", " << serializeJsonString(n_old.meta);
  63                 os << ") -> (" << serializeJsonString(n_new.name);
  64                 os << ", " << itos(n_new.param1);
  65                 os << ", " << itos(n_new.param2);
  66                 os << ", " << serializeJsonString(n_new.meta);
  67                 os << ')';
  68         case TYPE_MODIFY_INVENTORY_STACK:
  69                 os << "modify_inventory_stack (";
  70                 os << serializeJsonString(inventory_location);
  71                 os << ", " << serializeJsonString(inventory_list);
  72                 os << ", " << inventory_index;
  73                 os << ", " << (inventory_add ? "add" : "remove");
  74                 os << ", " << serializeJsonString(inventory_stack.getItemString());
  75                 os << ')';
  76         default:
  77                 return "<unknown action>";
  78         }
  79         return os.str();
  80 }
  81
  82
  83 bool RollbackAction::isImportant(IGameDef *gamedef) const
  84 {
  85         if (type != TYPE_SET_NODE)
  86                 return true;
  87         // If names differ, action is always important
  88         if(n_old.name != n_new.name)
  89                 return true;
  90         // If metadata differs, action is always important
  91         if(n_old.meta != n_new.meta)
  92                 return true;
  93         const NodeDefManager *ndef = gamedef->ndef();
  94         // Both are of the same name, so a single definition is needed
  95         const ContentFeatures &def = ndef->get(n_old.name);
  96         // If the type is flowing liquid, action is not important
  97         if (def.liquid_type == LIQUID_FLOWING)
  98                 return false;
  99         // Otherwise action is important
 100         return true;
 101 }
 102
 103
 104 bool RollbackAction::getPosition(v3s16 *dst) const
 105 {
 106         switch (type) {
 107         case TYPE_SET_NODE:
 108                 if (dst) *dst = p;
 109                 return true;
 110         case TYPE_MODIFY_INVENTORY_STACK: {
 111                 InventoryLocation loc;
 112                 loc.deSerialize(inventory_location);
 113                 if (loc.type != InventoryLocation::NODEMETA) {
 114                         return false;
 115                 }
 116                 if (dst) *dst = loc.p;
 117                 return true; }
 118         default:
 119                 return false;
 120         }
 121 }
 122
 123
 124 bool RollbackAction::applyRevert(Map *map, InventoryManager *imgr, IGameDef *gamedef) const
 125 {
 126         try {
 127                 switch (type) {
 128                 case TYPE_NOTHING:
 129                         return true;
 130                 case TYPE_SET_NODE: {
 131                         const NodeDefManager *ndef = gamedef->ndef();
 132                         // Make sure position is loaded from disk
 133                         map->emergeBlock(getContainerPos(p, MAP_BLOCKSIZE), false);
 134                         // Check current node
 135                         MapNode current_node = map->getNode(p);
 136                         std::string current_name = ndef->get(current_node).name;
 137                         // If current node not the new node, it's bad
 138                         if (current_name != n_new.name) {
 139                                 return false;
 140                         }
 141                         // Create rollback node
 142                         content_t id = CONTENT_IGNORE;
 143                         if (!ndef->getId(n_old.name, id)) {
 144                                 // The old node is not registered
 145                                 return false;
 146                         }
 147                         MapNode n(id, n_old.param1, n_old.param2);
 148                         // Set rollback node
 149                         try {
 150                                 if (!map->addNodeWithEvent(p, n)) {
 151                                         infostream << "RollbackAction::applyRevert(): "
 152                                                 << "AddNodeWithEvent failed at "
 153                                                 << PP(p) << " for " << n_old.name
 154                                                 << std::endl;
 155                                         return false;
 156                                 }
 157                                 if (n_old.meta.empty()) {
 158                                         map->removeNodeMetadata(p);
 159                                 } else {
 160                                         NodeMetadata *meta = map->getNodeMetadata(p);
 161                                         if (!meta) {
 162                                                 meta = new NodeMetadata(gamedef->idef());
 163                                                 if (!map->setNodeMetadata(p, meta)) {
 164                                                         delete meta;
 165                                                         infostream << "RollbackAction::applyRevert(): "
 166                                                                 << "setNodeMetadata failed at "
 167                                                                 << PP(p) << " for " << n_old.name
 168                                                                 << std::endl;
 169                                                         return false;
 170                                                 }
 171                                         }
 172                                         std::istringstream is(n_old.meta, std::ios::binary);
 173                                         meta->deSerialize(is, 1); // FIXME: version bump??
 174                                 }
 175                                 // Inform other things that the meta data has changed
 176                                 MapEditEvent event;
 177                                 event.type = MEET_BLOCK_NODE_METADATA_CHANGED;
 178                                 event.p = p;
 179                                 map->dispatchEvent(&event);
 180                         } catch (InvalidPositionException &e) {
 181                                 infostream << "RollbackAction::applyRevert(): "
 182                                         << "InvalidPositionException: " << e.what()
 183                                         << std::endl;
 184                                 return false;
 185                         }
 186                         // Success
 187                         return true; }
 188                 case TYPE_MODIFY_INVENTORY_STACK: {
 189                         InventoryLocation loc;
 190                         loc.deSerialize(inventory_location);
 191                         Inventory *inv = imgr->getInventory(loc);
 192                         if (!inv) {
 193                                 infostream << "RollbackAction::applyRevert(): Could not get "
 194                                         "inventory at " << inventory_location << std::endl;
 195                                 return false;
 196                         }
 197                         InventoryList *list = inv->getList(inventory_list);
 198                         if (!list) {
 199                                 infostream << "RollbackAction::applyRevert(): Could not get "
 200                                         "inventory list \"" << inventory_list << "\" in "
 201                                         << inventory_location << std::endl;
 202                                 return false;
 203                         }
 204                         if (list->getSize() <= inventory_index) {
 205                                 infostream << "RollbackAction::applyRevert(): List index "
 206                                         << inventory_index << " too large in "
 207                                         << "inventory list \"" << inventory_list << "\" in "
 208                                         << inventory_location << std::endl;
 209                                 return false;
 210                         }
 211
 212                         // If item was added, take away item, otherwise add removed item
 213                         if (inventory_add) {
 214                                 // Silently ignore different current item
 215                                 if (list->getItem(inventory_index).name !=
 216                                                 gamedef->idef()->getAlias(inventory_stack.name))
 217                                         return false;
 218                                 list->takeItem(inventory_index, inventory_stack.count);
 219                         } else {
 220                                 list->addItem(inventory_index, inventory_stack);
 221                         }
 222                         // Inventory was modified; send to clients
 223                         imgr->setInventoryModified(loc);
 224                         return true; }
 225                 default:
 226                         errorstream << "RollbackAction::applyRevert(): type not handled"
 227                                 << std::endl;
 228                         return false;
 229                 }
 230         } catch(SerializationError &e) {
 231                 errorstream << "RollbackAction::applyRevert(): n_old.name=" << n_old.name
 232                                 << ", SerializationError: " << e.what() << std::endl;
 233         }
 234         return false;
 235 }
 236