PaperMC/nms-patches/ItemStack.patch

--- a/net/minecraft/server/ItemStack.java
+++ b/net/minecraft/server/ItemStack.java
@@ -5,6 +5,19 @@
 import java.text.DecimalFormat;
 import java.util.Random;
 
+// CraftBukkit start
+import java.util.List;
+import java.util.Map;
+
+import org.bukkit.Location;
+import org.bukkit.TreeType;
+import org.bukkit.block.BlockState;
+import org.bukkit.craftbukkit.block.CraftBlockState;
+import org.bukkit.craftbukkit.util.CraftMagicNumbers;
+import org.bukkit.entity.Player;
+import org.bukkit.event.world.StructureGrowEvent;
+// CraftBukkit end
+
 public final class ItemStack {
 
     public static final DecimalFormat a = new DecimalFormat("#.###");
@@ -46,10 +59,14 @@
         this.k = false;
         this.item = item;
         this.count = i;
-        this.damage = j;
-        if (this.damage < 0) {
-            this.damage = 0;
-        }
+
+        // CraftBukkit start - Pass to setData to do filtering
+        this.setData(j);
+        //this.damage = j;
+        //if (this.damage < 0) {
+        //    this.damage = 0;
+        //}
+        // CraftBukkit end
 
     }
 
@@ -83,11 +100,128 @@
     }
 
     public boolean placeItem(EntityHuman entityhuman, World world, BlockPosition blockposition, EnumDirection enumdirection, float f, float f1, float f2) {
+        // CraftBukkit start - handle all block place event logic here
+        int data = this.getData();
+        int count = this.count;
+
+        if (!(this.getItem() instanceof ItemBucket)) { // if not bucket
+            world.captureBlockStates = true;
+            // special case bonemeal
+            if (this.getItem() instanceof ItemDye && this.getData() == 15) {
+                Block block = world.getType(blockposition).getBlock();
+                if (block == Blocks.SAPLING || block instanceof BlockMushroom) {
+                    world.captureTreeGeneration = true;
+                }
+            }
+        }
         boolean flag = this.getItem().interactWith(this, entityhuman, world, blockposition, enumdirection, f, f1, f2);
+        int newData = this.getData();
+        int newCount = this.count;
+        this.count = count;
+        this.setData(data);
+        world.captureBlockStates = false;
+        if (flag && world.captureTreeGeneration && world.capturedBlockStates.size() > 0) {
+            world.captureTreeGeneration = false;
+            Location location = new Location(world.getWorld(), blockposition.getX(), blockposition.getY(), blockposition.getZ());
+            TreeType treeType = BlockSapling.treeType;
+            BlockSapling.treeType = null;
+            List<BlockState> blocks = (List<BlockState>) world.capturedBlockStates.clone();
+            world.capturedBlockStates.clear();
+            StructureGrowEvent event = null;
+            if (treeType != null) {
+                boolean isBonemeal = getItem() == Items.DYE && data == 15;
+                event = new StructureGrowEvent(location, treeType, isBonemeal, (Player) entityhuman.getBukkitEntity(), blocks);
+                org.bukkit.Bukkit.getPluginManager().callEvent(event);
+            }
+            if (event == null || !event.isCancelled()) {
+                // Change the stack to its new contents if it hasn't been tampered with.
+                if (this.count == count && this.getData() == data) {
+                    this.setData(newData);
+                    this.count = newCount;
+                }
+                for (BlockState blockstate : blocks) {
+                    blockstate.update(true);
+                }
+            }
+
+            return flag;
+        }
+        world.captureTreeGeneration = false;
 
         if (flag) {
-            entityhuman.b(StatisticList.USE_ITEM_COUNT[Item.getId(this.item)]);
+            org.bukkit.event.block.BlockPlaceEvent placeEvent = null;
+            List<BlockState> blocks = (List<BlockState>) world.capturedBlockStates.clone();
+            world.capturedBlockStates.clear();
+            if (blocks.size() > 1) {
+                placeEvent = org.bukkit.craftbukkit.event.CraftEventFactory.callBlockMultiPlaceEvent(world, entityhuman, blocks, blockposition.getX(), blockposition.getY(), blockposition.getZ());
+            } else if (blocks.size() == 1) {
+                placeEvent = org.bukkit.craftbukkit.event.CraftEventFactory.callBlockPlaceEvent(world, entityhuman, blocks.get(0), blockposition.getX(), blockposition.getY(), blockposition.getZ());
+            }
+
+            if (placeEvent != null && (placeEvent.isCancelled() || !placeEvent.canBuild())) {
+                flag = false; // cancel placement
+                // revert back all captured blocks
+                for (BlockState blockstate : blocks) {
+                    blockstate.update(true, false);
+                }
+            } else {
+                // Change the stack to its new contents if it hasn't been tampered with.
+                if (this.count == count && this.getData() == data) {
+                    this.setData(newData);
+                    this.count = newCount;
+                }
+                for (BlockState blockstate : blocks) {
+                    int x = blockstate.getX();
+                    int y = blockstate.getY();
+                    int z = blockstate.getZ();
+                    int updateFlag = ((CraftBlockState) blockstate).getFlag();
+                    org.bukkit.Material mat = blockstate.getType();
+                    Block oldBlock = CraftMagicNumbers.getBlock(mat);
+                    BlockPosition newblockposition = new BlockPosition(x, y, z);
+                    IBlockData block = world.getType(newblockposition);
+
+                    if (!(block instanceof BlockContainer)) { // Containers get placed automatically
+                        block.getBlock().onPlace(world, newblockposition, block);
+                    }
+
+                    world.notifyAndUpdatePhysics(newblockposition, null, oldBlock, block.getBlock(), updateFlag); // send null chunk as chunk.k() returns false by this point
+                }
+
+                for (Map.Entry<BlockPosition, TileEntity> e : world.capturedTileEntities.entrySet()) {
+                    world.setTileEntity(e.getKey(), e.getValue());
+                }
+
+                // Special case juke boxes as they update their tile entity. Copied from ItemRecord.
+                if (this.getItem() instanceof ItemRecord) {
+                    ((BlockJukeBox) Blocks.JUKEBOX).a(world, blockposition, world.getType(blockposition), this);
+                    world.a((EntityHuman) null, 1005, blockposition, Item.getId(this.getItem()));
+                    --this.count;
+                    entityhuman.b(StatisticList.X);
+                }
+
+                if (this.getItem() == Items.SKULL) { // Special case skulls to allow wither spawns to be cancelled
+                    BlockPosition bp = blockposition;
+                    if (!world.getType(blockposition).getBlock().a(world, blockposition)) {
+                        if (!world.getType(blockposition).getBlock().getMaterial().isBuildable()) {
+                            bp = null;
+                        } else {
+                            bp = bp.shift(enumdirection);
+                        }
+                    }
+                    if (bp != null) {
+                        TileEntity te = world.getTileEntity(bp);
+                        if (te instanceof TileEntitySkull) {
+                            Blocks.SKULL.a(world, bp, (TileEntitySkull) te);
+                        }
+                    }
+                }
+
+                entityhuman.b(StatisticList.USE_ITEM_COUNT[Item.getId(this.item)]);
+            }
         }
+        world.capturedTileEntities.clear();
+        world.capturedBlockStates.clear();
+        // CraftBukkit end
 
         return flag;
     }
@@ -111,7 +245,7 @@
         nbttagcompound.setByte("Count", (byte) this.count);
         nbttagcompound.setShort("Damage", (short) this.damage);
         if (this.tag != null) {
-            nbttagcompound.set("tag", this.tag);
+            nbttagcompound.set("tag", this.tag.clone()); // CraftBukkit - make defensive copy, data is going to another thread
         }
 
         return nbttagcompound;
@@ -125,13 +259,18 @@
         }
 
         this.count = nbttagcompound.getByte("Count");
+        /* CraftBukkit start - Route through setData for filtering
         this.damage = nbttagcompound.getShort("Damage");
         if (this.damage < 0) {
             this.damage = 0;
         }
+        */
+        this.setData(nbttagcompound.getShort("Damage"));
+        // CraftBukkit end
 
         if (nbttagcompound.hasKeyOfType("tag", 10)) {
-            this.tag = nbttagcompound.getCompound("tag");
+            // CraftBukkit - make defensive copy as this data may be coming from the save thread
+            this.tag = (NBTTagCompound) nbttagcompound.getCompound("tag").clone();
             if (this.item != null) {
                 this.item.a(this.tag);
             }
@@ -168,8 +307,28 @@
     }
 
     public void setData(int i) {
+        // CraftBukkit start - Filter out data for items that shouldn't have it
+        // The crafting system uses this value for a special purpose so we have to allow it
+        if (i == 32767) {
+            this.damage = i;
+            return;
+        }
+
+        // Is this a block?
+        if (CraftMagicNumbers.getBlock(CraftMagicNumbers.getId(this.getItem())) != Blocks.AIR) {
+            // If vanilla doesn't use data on it don't allow any
+            if (!(this.usesData() || this.getItem().usesDurability())) {
+                i = 0;
+            }
+        }
+
+        // Filter invalid plant data
+        if (CraftMagicNumbers.getBlock(CraftMagicNumbers.getId(this.getItem())) == Blocks.DOUBLE_PLANT && (i > 5 || i < 0)) {
+            i = 0;
+        }
+        // CraftBukkit end
         this.damage = i;
-        if (this.damage < 0) {
+        if (this.damage < -1) { // CraftBukkit
             this.damage = 0;
         }
 
@@ -223,6 +382,12 @@
                         this.count = 0;
                     }
 
+                    // CraftBukkit start - Check for item breaking
+                    if (this.count == 0 && entityliving instanceof EntityHuman) {
+                        org.bukkit.craftbukkit.event.CraftEventFactory.callPlayerItemBreakEvent((EntityHuman) entityliving, this);
+                    }
+                    // CraftBukkit end
+
                     this.damage = 0;
                 }
 
@@ -489,6 +654,7 @@
 
     public void setItem(Item item) {
         this.item = item;
+        this.setData(this.getData()); // CraftBukkit - Set data again to ensure it is filtered properly
     }
 
     public IChatBaseComponent C() {