diff --git a/apps/i2psnark/java/src/net/i2p/kademlia/XORComparator.java b/apps/i2psnark/java/src/net/i2p/kademlia/XORComparator.java index 8d8cb5663a4df0112f09e4d3dd04fe2d6a29fac5..2ac5017ddfe6b52d16ed96f1735f6566f0fbe5c9 100644 --- a/apps/i2psnark/java/src/net/i2p/kademlia/XORComparator.java +++ b/apps/i2psnark/java/src/net/i2p/kademlia/XORComparator.java @@ -2,7 +2,6 @@ package net.i2p.kademlia; import java.util.Comparator; -import net.i2p.data.DataHelper; import net.i2p.data.SimpleDataStructure; /** @@ -21,8 +20,20 @@ class XORComparator<T extends SimpleDataStructure> implements Comparator<T> { } public int compare(T lhs, T rhs) { - byte lhsDelta[] = DataHelper.xor(lhs.getData(), _base); - byte rhsDelta[] = DataHelper.xor(rhs.getData(), _base); - return DataHelper.compareTo(lhsDelta, rhsDelta); + // same as the following but byte-by-byte for efficiency + //byte lhsDelta[] = DataHelper.xor(lhs.getData(), _base); + //byte rhsDelta[] = DataHelper.xor(rhs.getData(), _base); + //return DataHelper.compareTo(lhsDelta, rhsDelta); + byte lhsb[] = lhs.getData(); + byte rhsb[] = rhs.getData(); + for (int i = 0; i < _base.length; i++) { + int ld = (lhsb[i] ^ _base[i]) & 0xff; + int rd = (rhsb[i] ^ _base[i]) & 0xff; + if (ld < rd) + return -1; + if (ld > rd) + return 1; + } + return 0; } } diff --git a/router/java/src/net/i2p/router/networkdb/kademlia/XORComparator.java b/router/java/src/net/i2p/router/networkdb/kademlia/XORComparator.java index 9242103cd399efcf3a9598b3bdb81cd5cbf8b563..cd734b685f80e82fb002f259487bfa2fa798ea1d 100644 --- a/router/java/src/net/i2p/router/networkdb/kademlia/XORComparator.java +++ b/router/java/src/net/i2p/router/networkdb/kademlia/XORComparator.java @@ -2,32 +2,35 @@ package net.i2p.router.networkdb.kademlia; import java.util.Comparator; -import net.i2p.data.DataHelper; import net.i2p.data.Hash; /** * Help sort Hashes in relation to a base key using the XOR metric. - * Warning - not thread safe. */ class XORComparator implements Comparator<Hash> { private final byte[] _base; - private final byte[] _lx, _rx; /** * @param target key to compare distances with */ public XORComparator(Hash target) { _base = target.getData(); - _lx = new byte[Hash.HASH_LENGTH]; - _rx = new byte[Hash.HASH_LENGTH]; } /** * getData() of args must be non-null */ public int compare(Hash lhs, Hash rhs) { - DataHelper.xor(lhs.getData(), 0, _base, 0, _lx, 0, Hash.HASH_LENGTH); - DataHelper.xor(rhs.getData(), 0, _base, 0, _rx, 0, Hash.HASH_LENGTH); - return DataHelper.compareTo(_lx, _rx); + byte lhsb[] = lhs.getData(); + byte rhsb[] = rhs.getData(); + for (int i = 0; i < _base.length; i++) { + int ld = (lhsb[i] ^ _base[i]) & 0xff; + int rd = (rhsb[i] ^ _base[i]) & 0xff; + if (ld < rd) + return -1; + if (ld > rd) + return 1; + } + return 0; } }