From: Francis Dupont <fdupont@isc.org>
Date: Sat, 20 Jun 2020 11:54:08 +0000 (+0200)
Subject: [#1283] Optimized hash
X-Git-Tag: Kea-1.7.10~32
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=392d1e5926cf46d3a6c81a8858f06b1ac5d86d87;p=thirdparty%2Fkea.git

[#1283] Optimized hash
---

diff --git a/src/lib/asiolink/io_address.cc b/src/lib/asiolink/io_address.cc
index a9eb587c33..a2a0a788cc 100644
--- a/src/lib/asiolink/io_address.cc
+++ b/src/lib/asiolink/io_address.cc
@@ -173,10 +173,15 @@ IOAddress::increase(const IOAddress& addr) {
     return (IOAddress::fromBytes(addr.getFamily(), &packed[0]));
 }
 
-std::size_t
+size_t
 hash_value(const IOAddress& address) {
-    boost::hash<std::vector<uint8_t> > hasher;
-    return (hasher(address.toBytes()));
+    if (address.isV4()) {
+        boost::hash<uint32_t> hasher;
+        return (hasher(address.toUint32()));
+    } else {
+        boost::hash<std::vector<uint8_t> > hasher;
+        return (hasher(address.toBytes()));
+    }
 }
 
 } // namespace asiolink
diff --git a/src/lib/asiolink/io_address.h b/src/lib/asiolink/io_address.h
index 91e415dd92..fb1d67b3ea 100644
--- a/src/lib/asiolink/io_address.h
+++ b/src/lib/asiolink/io_address.h
@@ -305,10 +305,13 @@ operator<<(std::ostream& os, const IOAddress& address);
 /// \brief Hash the IOAddress.
 ///
 /// This method allows boost multi-index hashed indexes on IOAddresses.
+/// It follows the requirement with equality: if two addresses are equal
+/// their hashes are equal, if two addresses are not equal their hashes
+/// are almost surely not equal.
 ///
 /// \param address A \c IOAddress to hash.
 /// \return The hash of the IOAddress.
-std::size_t hash_value(const IOAddress& address);
+size_t hash_value(const IOAddress& address);
 
 } // namespace asiolink
 } // namespace isc