[2549] Changes as a result of the code review.

src/lib/dhcp/iface_mgr.cc

@@ -212,7 +212,7 @@ bool IfaceMgr::openSockets4(const uint16_t port) {
              addr != addrs.end();
              ++addr) {
 
-            // Skip IPv6 addresses
+            // Skip all but V4 addresses.
             if (!addr->isV4()) {
                 continue;
             }
@@ -247,7 +247,7 @@ bool IfaceMgr::openSockets6(const uint16_t port) {
              addr != addrs.end();
              ++addr) {
 
-            // skip IPv4 addresses
+            // Skip all but V6 addresses.
             if (!addr->isV6()) {
                 continue;
             }
@@ -949,7 +949,7 @@ Pkt6Ptr IfaceMgr::receive6(uint32_t timeout_sec, uint32_t timeout_usec /* = 0 */
         for (SocketCollection::const_iterator s = socket_collection.begin();
              s != socket_collection.end(); ++s) {
 
-            // Only deal with IPv4 addresses.
+            // Only deal with IPv6 addresses.
             if (s->addr_.isV6()) {
                 names << s->sockfd_ << "(" << iface->getName() << ") ";
 

src/lib/dhcp/option_definition.cc

@@ -381,9 +381,7 @@ OptionDefinition::writeToBuffer(const std::string& value,
             asiolink::IOAddress address(value);
             if (!address.isV4() && !address.isV6()) {
                 isc_throw(BadDataTypeCast, "provided address " << address.toText()
-                          << " is not a valid "
-                          << (address.isV4() ? "IPv4" : "IPv6")
-                          << " address");
+                          << " is not a valid IPv4 or IPv6 address.");
             }
             OptionDataTypeUtil::writeAddress(address, buf);
             return;

src/lib/dhcpsrv/addr_utilities.cc

@@ -53,8 +53,11 @@ isc::asiolink::IOAddress firstAddrInPrefix6(const isc::asiolink::IOAddress& pref
     }
 
     // First we copy the whole address as 16 bytes.
+    // We don't check that it is a valid IPv6 address and thus has
+    // the required length because it is already checked by
+    // the calling function.
     uint8_t packed[V6ADDRESS_LEN];
-    memcpy(packed, &prefix.toBytes()[0], 16);
+    memcpy(packed, &prefix.toBytes()[0], V6ADDRESS_LEN);
 
     // If the length is divisible by 8, it is simple. We just zero out the host
     // part. Otherwise we need to handle the byte that has to be partially
@@ -95,6 +98,9 @@ isc::asiolink::IOAddress firstAddrInPrefix4(const isc::asiolink::IOAddress& pref
         isc_throw(isc::BadValue, "Too large netmask. 0..32 is allowed in IPv4");
     }
 
+    // We don't check that it is a valid IPv4 address and thus has
+    // a required length of 4 bytes because it has been already
+    // checked by the calling function.
     uint32_t addr = prefix;
     return (IOAddress(addr & (~bitMask4[len])));
 }

src/lib/dhcpsrv/alloc_engine.cc

@@ -30,20 +30,21 @@ AllocEngine::IterativeAllocator::IterativeAllocator()
 
 isc::asiolink::IOAddress
 AllocEngine::IterativeAllocator::increaseAddress(const isc::asiolink::IOAddress& addr) {
+    // Get a buffer holding an address.
+    const std::vector<uint8_t>& vec = addr.toBytes();
+    // Get the address length.
+    const int len = vec.size();
+
+    // Since the same array will be used to hold the IPv4 and IPv6
+    // address we have to make sure that the size of the array
+    // we allocate will work for both types of address.
+    BOOST_STATIC_ASSERT(V4ADDRESS_LEN <= V6ADDRESS_LEN);
     uint8_t packed[V6ADDRESS_LEN];
-    int len;
 
-    // First we copy the whole address as 16 bytes.
-    if (addr.isV4()) {
-        // IPv4
-        std::memcpy(packed, &addr.toBytes()[0], 4);
-        len = 4;
-    } else {
-        // IPv6
-        std::memcpy(packed, &addr.toBytes()[0], 16);
-        len = 16;
-    }
+    // Copy the address. It can be either V4 or V6.
+    std::memcpy(packed, &vec[0], len);
 
+    // Increase the address.
     for (int i = len - 1; i >= 0; --i) {
         ++packed[i];
         if (packed[i] != 0) {