[5315] Added functions that remove subnets from a configuration.

src/lib/dhcpsrv/cfg_subnets4.cc

@@ -39,6 +39,20 @@ CfgSubnets4::add(const Subnet4Ptr& subnet) {
     subnets_.push_back(subnet);
 }
 
+void
+CfgSubnets4::del(const ConstSubnet4Ptr& subnet) {
+    auto& index = subnets_.get<SubnetIdIndexTag>();
+    auto subnet_it = index.find(subnet->getID());
+    if (subnet_it == index.end()) {
+        isc_throw(BadValue, "no subnet with ID of '" << subnet->getID()
+                  << "' found");
+    }
+    index.erase(subnet_it);
+
+    LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE, DHCPSRV_CFGMGR_DEL_SUBNET4)
+        .arg(subnet->toText());
+}
+
 ConstSubnet4Ptr
 CfgSubnets4::getBySubnetId(const SubnetID& subnet_id) const {
     const auto& index = subnets_.get<SubnetSubnetIdIndexTag>();

src/lib/dhcpsrv/cfg_subnets4.h

@@ -39,6 +39,13 @@ public:
     /// duplicates id of an existing subnet.
     void add(const Subnet4Ptr& subnet);
 
+    /// @brief Removes subnet from the configuration.
+    ///
+    /// @param subnet Pointer to the subnet to be removed.
+    ///
+    /// @throw isc::BadValue if such subnet doesn't exist.
+    void del(const ConstSubnet4Ptr& subnet);
+
     /// @brief Returns pointer to the collection of all IPv4 subnets.
     ///
     /// This is used in a hook (subnet4_select), where the hook is able

src/lib/dhcpsrv/cfg_subnets6.cc

@@ -38,6 +38,20 @@ CfgSubnets6::add(const Subnet6Ptr& subnet) {
     subnets_.push_back(subnet);
 }
 
+void
+CfgSubnets6::del(const ConstSubnet6Ptr& subnet) {
+    auto& index = subnets_.get<SubnetIdIndexTag>();
+    auto subnet_it = index.find(subnet->getID());
+    if (subnet_it == index.end()) {
+        isc_throw(BadValue, "no subnet with ID of '" << subnet->getID()
+                  << "' found");
+    }
+    index.erase(subnet_it);
+
+    LOG_DEBUG(dhcpsrv_logger, DHCPSRV_DBG_TRACE, DHCPSRV_CFGMGR_DEL_SUBNET6)
+        .arg(subnet->toText());
+}
+
 ConstSubnet6Ptr
 CfgSubnets6::getBySubnetId(const SubnetID& subnet_id) const {
     const auto& index = subnets_.get<SubnetSubnetIdIndexTag>();

src/lib/dhcpsrv/cfg_subnets6.h

@@ -40,6 +40,13 @@ public:
     /// duplicates id of an existing subnet.
     void add(const Subnet6Ptr& subnet);
 
+    /// @brief Removes subnet from the configuration.
+    ///
+    /// @param subnet Pointer to the subnet to be removed.
+    ///
+    /// @throw isc::BadValue if such subnet doesn't exist.
+    void del(const ConstSubnet6Ptr& subnet);
+
     /// @brief Returns pointer to the collection of all IPv6 subnets.
     ///
     /// This is used in a hook (subnet6_select), where the hook is able

src/lib/dhcpsrv/dhcpsrv_messages.mes

@@ -44,6 +44,13 @@ there is a good reason for it, to avoid increased number of renewals and
 a need for rebinding (increase of multicast traffic, which may be received
 by multiple servers).
 
+% DHCPSRV_CFGMGR_DEL_SUBNET4 IPv4 subnet %1 removed
+This debug message is issued when a subnet is successfully removed from the
+server configuration. The argument identifies the subnet removed.
+
+% DHCPSRV_CFGMGR_DEL_SUBNET6 IPv6 subnet %1 removed
+This debug message is issued when a subnet is successfully removed from the
+
 % DHCPSRV_CFGMGR_NEW_SUBNET4 a new subnet has been added to configuration: %1
 This is an informational message reporting that the configuration has
 been extended to include the specified IPv4 subnet.

src/lib/dhcpsrv/tests/cfg_subnets4_unittest.cc

@@ -74,6 +74,34 @@ TEST(CfgSubnets4Test, getSpecificSubnet) {
     EXPECT_FALSE(cfg.getByPrefix("10.20.30.0/29"));
 }
 
+// This test verifies that a single subnet can be removed from the configuration.
+TEST(CfgSubnets4Test, deleteSubnet) {
+    CfgSubnets4 cfg;
+
+    // Create 3 subnets.
+    Subnet4Ptr subnet1(new Subnet4(IOAddress("192.0.2.0"),
+                                   26, 1, 2, 3, SubnetID(5)));
+    Subnet4Ptr subnet2(new Subnet4(IOAddress("192.0.3.0"),
+                                   26, 1, 2, 3, SubnetID(8)));
+    Subnet4Ptr subnet3(new Subnet4(IOAddress("192.0.4.0"),
+                                   26, 1, 2, 3, SubnetID(10)));
+
+    ASSERT_NO_THROW(cfg.add(subnet1));
+    ASSERT_NO_THROW(cfg.add(subnet2));
+    ASSERT_NO_THROW(cfg.add(subnet3));
+
+    // There should be three subnets.
+    ASSERT_EQ(3, cfg.getAll()->size());
+    // We're going to remove the subnet #2. Let's make sure it exists before
+    // we remove it.
+    ASSERT_TRUE(cfg.getByPrefix("192.0.3.0/26"));
+
+    // Remove the subnet and make sure it is gone.
+    ASSERT_NO_THROW(cfg.del(subnet2));
+    ASSERT_EQ(2, cfg.getAll()->size());
+    EXPECT_FALSE(cfg.getByPrefix("192.0.3.0/26"));
+}
+
 // This test verifies that it is possible to retrieve a subnet using an
 // IP address.
 TEST(CfgSubnets4Test, selectSubnetByCiaddr) {

src/lib/dhcpsrv/tests/cfg_subnets6_unittest.cc

@@ -83,6 +83,31 @@ TEST(CfgSubnets6Test, getSpecificSubnet) {
     EXPECT_FALSE(cfg.getByPrefix("3000::/16"));
 }
 
+// This test verifies that a single subnet can be removed from the configuration.
+TEST(CfgSubnets6Test, deleteSubnet) {
+    CfgSubnets6 cfg;
+
+    // Create 3 subnets.
+    Subnet6Ptr subnet1(new Subnet6(IOAddress("2001:db8:1::"), 48, 1, 2, 3, 4));
+    Subnet6Ptr subnet2(new Subnet6(IOAddress("2001:db8:2::"), 48, 1, 2, 3, 4));
+    Subnet6Ptr subnet3(new Subnet6(IOAddress("2001:db8:3::"), 48, 1, 2, 3, 4));
+
+    ASSERT_NO_THROW(cfg.add(subnet1));
+    ASSERT_NO_THROW(cfg.add(subnet2));
+    ASSERT_NO_THROW(cfg.add(subnet3));
+
+    // There should be three subnets.
+    ASSERT_EQ(3, cfg.getAll()->size());
+    // We're going to remove the subnet #2. Let's make sure it exists before
+    // we remove it.
+    ASSERT_TRUE(cfg.getByPrefix("2001:db8:2::/48"));
+
+    // Remove the subnet and make sure it is gone.
+    ASSERT_NO_THROW(cfg.del(subnet2));
+    ASSERT_EQ(2, cfg.getAll()->size());
+    EXPECT_FALSE(cfg.getByPrefix("2001:db8:2::/48"));
+}
+
 // This test checks that the subnet can be selected using a relay agent's
 // link address.
 TEST(CfgSubnets6Test, selectSubnetByRelayAddress) {