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 "map.h"
  26 #include "gamedef.h"
  27 #include "nodedef.h"
  28 #include "nodemetadata.h"
  29 #include "exceptions.h"
  30 #include "log.h"
  31 #include "inventorymanager.h"
  32 #include "inventory.h"
  33 #include "mapblock.h"
  34
  35 #define PP(x) "("<<(x).X<<","<<(x).Y<<","<<(x).Z<<")"
  36
  37
  38 RollbackNode::RollbackNode(Map *map, v3s16 p, IGameDef *gamedef)
  39 {
  40         INodeDefManager *ndef = gamedef->ndef();
  41         MapNode n = map->getNodeNoEx(p);
  42         name = ndef->get(n).name;
  43         param1 = n.param1;
  44         param2 = n.param2;
  45         NodeMetadata *metap = map->getNodeMetadata(p);
  46         if (metap) {
  47                 std::ostringstream os(std::ios::binary);
  48                 metap->serialize(os);
  49                 meta = os.str();
  50         }
  51 }
  52
  53
  54 std::string RollbackAction::toString() const
  55 {
  56         std::ostringstream os(std::ios::binary);
  57         switch (type) {
  58         case TYPE_SET_NODE:
  59                 os << "set_node " << PP(p);
  60                 os << ": (" << serializeJsonString(n_old.name);
  61                 os << ", " << itos(n_old.param1);
  62                 os << ", " << itos(n_old.param2);
  63                 os << ", " << serializeJsonString(n_old.meta);
  64                 os << ") -> (" << serializeJsonString(n_new.name);
  65                 os << ", " << itos(n_new.param1);
  66                 os << ", " << itos(n_new.param2);
  67                 os << ", " << serializeJsonString(n_new.meta);
  68                 os << ')';
  69         case TYPE_MODIFY_INVENTORY_STACK:
  70                 os << "modify_inventory_stack (";
  71                 os << serializeJsonString(inventory_location);
  72                 os << ", " << serializeJsonString(inventory_list);
  73                 os << ", " << inventory_index;
  74                 os << ", " << (inventory_add ? "add" : "remove");
  75                 os << ", " << serializeJsonString(inventory_stack.getItemString());
  76                 os << ')';
  77         default:
  78                 return "<unknown action>";
  79         }
  80         return os.str();
  81 }
  82
  83
  84 bool RollbackAction::isImportant(IGameDef *gamedef) const
  85 {
  86         if (type != TYPE_SET_NODE)
  87                 return true;
  88         // If names differ, action is always important
  89         if(n_old.name != n_new.name)
  90                 return true;
  91         // If metadata differs, action is always important
  92         if(n_old.meta != n_new.meta)
  93                 return true;
  94         INodeDefManager *ndef = gamedef->ndef();
  95         // Both are of the same name, so a single definition is needed
  96         const ContentFeatures &def = ndef->get(n_old.name);
  97         // If the type is flowing liquid, action is not important
  98         if (def.liquid_type == LIQUID_FLOWING)
  99                 return false;
 100         // Otherwise action is important
 101         return true;
 102 }
 103
 104
 105 bool RollbackAction::getPosition(v3s16 *dst) const
 106 {
 107         switch (type) {
 108         case TYPE_SET_NODE:
 109                 if (dst) *dst = p;
 110                 return true;
 111         case TYPE_MODIFY_INVENTORY_STACK: {
 112                 InventoryLocation loc;
 113                 loc.deSerialize(inventory_location);
 114                 if (loc.type != InventoryLocation::NODEMETA) {
 115                         return false;
 116                 }
 117                 if (dst) *dst = loc.p;
 118                 return true; }
 119         default:
 120                 return false;
 121         }
 122 }
 123
 124
 125 bool RollbackAction::applyRevert(Map *map, InventoryManager *imgr, IGameDef *gamedef) const
 126 {
 127         try {
 128                 switch (type) {
 129                 case TYPE_NOTHING:
 130                         return true;
 131                 case TYPE_SET_NODE: {
 132                         INodeDefManager *ndef = gamedef->ndef();
 133                         // Make sure position is loaded from disk
 134                         map->emergeBlock(getContainerPos(p, MAP_BLOCKSIZE), false);
 135                         // Check current node
 136                         MapNode current_node = map->getNodeNoEx(p);
 137                         std::string current_name = ndef->get(current_node).name;
 138                         // If current node not the new node, it's bad
 139                         if (current_name != n_new.name) {
 140                                 return false;
 141                         }
 142                         // Create rollback node
 143                         MapNode n(ndef, n_old.name, n_old.param1, n_old.param2);
 144                         // Set rollback node
 145                         try {
 146                                 if (!map->addNodeWithEvent(p, n)) {
 147                                         infostream << "RollbackAction::applyRevert(): "
 148                                                 << "AddNodeWithEvent failed at "
 149                                                 << PP(p) << " for " << n_old.name
 150                                                 << std::endl;
 151                                         return false;
 152                                 }
 153                                 if (n_old.meta.empty()) {
 154                                         map->removeNodeMetadata(p);
 155                                 } else {
 156                                         NodeMetadata *meta = map->getNodeMetadata(p);
 157                                         if (!meta) {
 158                                                 meta = new NodeMetadata(gamedef);
 159                                                 if (!map->setNodeMetadata(p, meta)) {
 160                                                         delete meta;
 161                                                         infostream << "RollbackAction::applyRevert(): "
 162                                                                 << "setNodeMetadata failed at "
 163                                                                 << PP(p) << " for " << n_old.name
 164                                                                 << std::endl;
 165                                                         return false;
 166                                                 }
 167                                         }
 168                                         std::istringstream is(n_old.meta, std::ios::binary);
 169                                         meta->deSerialize(is);
 170                                 }
 171                                 // Inform other things that the meta data has changed
 172                                 v3s16 blockpos = getContainerPos(p, MAP_BLOCKSIZE);
 173                                 MapEditEvent event;
 174                                 event.type = MEET_BLOCK_NODE_METADATA_CHANGED;
 175                                 event.p = blockpos;
 176                                 map->dispatchEvent(&event);
 177                                 // Set the block to be saved
 178                                 MapBlock *block = map->getBlockNoCreateNoEx(blockpos);
 179                                 if (block) {
 180                                         block->raiseModified(MOD_STATE_WRITE_NEEDED,
 181                                                 MOD_REASON_REPORT_META_CHANGE);
 182                                 }
 183                         } catch (InvalidPositionException &e) {
 184                                 infostream << "RollbackAction::applyRevert(): "
 185                                         << "InvalidPositionException: " << e.what()
 186                                         << std::endl;
 187                                 return false;
 188                         }
 189                         // Success
 190                         return true; }
 191                 case TYPE_MODIFY_INVENTORY_STACK: {
 192                         InventoryLocation loc;
 193                         loc.deSerialize(inventory_location);
 194                         std::string real_name = gamedef->idef()->getAlias(inventory_stack.name);
 195                         Inventory *inv = imgr->getInventory(loc);
 196                         if (!inv) {
 197                                 infostream << "RollbackAction::applyRevert(): Could not get "
 198                                         "inventory at " << inventory_location << std::endl;
 199                                 return false;
 200                         }
 201                         InventoryList *list = inv->getList(inventory_list);
 202                         if (!list) {
 203                                 infostream << "RollbackAction::applyRevert(): Could not get "
 204                                         "inventory list \"" << inventory_list << "\" in "
 205                                         << inventory_location << std::endl;
 206                                 return false;
 207                         }
 208                         if (list->getSize() <= inventory_index) {
 209                                 infostream << "RollbackAction::applyRevert(): List index "
 210                                         << inventory_index << " too large in "
 211                                         << "inventory list \"" << inventory_list << "\" in "
 212                                         << inventory_location << std::endl;
 213                                 return false;
 214                         }
 215                         // If item was added, take away item, otherwise add removed item
 216                         if (inventory_add) {
 217                                 // Silently ignore different current item
 218                                 if (list->getItem(inventory_index).name != real_name)
 219                                         return false;
 220                                 list->takeItem(inventory_index, inventory_stack.count);
 221                         } else {
 222                                 list->addItem(inventory_index, inventory_stack);
 223                         }
 224                         // Inventory was modified; send to clients
 225                         imgr->setInventoryModified(loc);
 226                         return true; }
 227                 default:
 228                         errorstream << "RollbackAction::applyRevert(): type not handled"
 229                                 << std::endl;
 230                         return false;
 231                 }
 232         } catch(SerializationError &e) {
 233                 errorstream << "RollbackAction::applyRevert(): n_old.name=" << n_old.name
 234                                 << ", SerializationError: " << e.what() << std::endl;
 235         }
 236         return false;
 237 }
 238