[3561] HostMgr now uses alternate host data source, if specified.

src/lib/dhcpsrv/host_mgr.cc

@@ -44,6 +44,9 @@ HostMgr::getHostMgrPtr() {
 void
 HostMgr::create(const std::string&) {
     getHostMgrPtr().reset(new HostMgr());
+
+    /// @todo Initialize alternate_source here, using the parameter.
+    /// For example: alternate_source.reset(new MysqlHostDataSource(access)).
 }
 
 HostMgr&
@@ -57,29 +60,51 @@ HostMgr::instance() {
 
 ConstHostCollection
 HostMgr::getAll(const HWAddrPtr& hwaddr, const DuidPtr& duid) const {
-    return (getCfgHosts()->getAll(hwaddr, duid));
+    ConstHostCollection hosts = getCfgHosts()->getAll(hwaddr, duid);
+    if (alternate_source) {
+        ConstHostCollection hosts_plus = alternate_source->getAll(hwaddr, duid);
+        hosts.insert(hosts.end(), hosts_plus.begin(), hosts_plus.end());
+    }
+    return (hosts);
 }
 
 ConstHostCollection
 HostMgr::getAll4(const IOAddress& address) const {
+    ConstHostCollection hosts = getCfgHosts()->getAll4(address);
+    if (alternate_source) {
+        ConstHostCollection hosts_plus = alternate_source->getAll4(address);
+        hosts.insert(hosts.end(), hosts_plus.begin(), hosts_plus.end());
+    }
     return (getCfgHosts()->getAll4(address));
 }
 
 ConstHostPtr
 HostMgr::get4(const SubnetID& subnet_id, const HWAddrPtr& hwaddr,
               const DuidPtr& duid) const {
-    return (getCfgHosts()->get4(subnet_id, hwaddr, duid));
+    ConstHostPtr host = getCfgHosts()->get4(subnet_id, hwaddr, duid);
+    if (!host && alternate_source) {
+        host = alternate_source->get4(subnet_id, hwaddr, duid);
+    }
+    return (host);
 }
 
 ConstHostPtr
 HostMgr::get6(const SubnetID& subnet_id, const DuidPtr& duid,
                const HWAddrPtr& hwaddr) const {
-    return (getCfgHosts()->get6(subnet_id, duid, hwaddr));
+    ConstHostPtr host = getCfgHosts()->get6(subnet_id, duid, hwaddr);
+    if (!host && alternate_source) {
+        host = alternate_source->get6(subnet_id, duid, hwaddr);
+    }
+    return (host);
 }
 
 ConstHostPtr
 HostMgr::get6(const IOAddress& prefix, const uint8_t prefix_len) const {
-    return (getCfgHosts()->get6(prefix, prefix_len));
+    ConstHostPtr host = getCfgHosts()->get6(prefix, prefix_len);
+    if (!host && alternate_source) {
+        host = alternate_source->get6(prefix, prefix_len);
+    }
+    return (host);
 }
 
 void

src/lib/dhcpsrv/host_mgr.h

@@ -15,6 +15,7 @@
 #ifndef HOST_MGR_H
 #define HOST_MGR_H
 
+#include <boost/noncopyable.hpp>
 #include <boost/scoped_ptr.hpp>
 
 namespace isc {
@@ -54,7 +55,7 @@ namespace dhcp {
 /// reservations specified in the configuration file) can't be disabled.
 ///
 /// @todo Implement alternate host data sources: MySQL, PostgreSQL, etc.
-class HostMgr : public BaseHostDataSource {
+class HostMgr : public boost::noncopyable, BaseHostDataSource {
 public:
 
     /// @brief Creates new instance of the @c HostMgr.
@@ -158,14 +159,23 @@ public:
     /// This method will throw an exception if no alternate data source is
     /// in use.
     ///
-    /// @param Pointer to the new @c Host object being added.
+    /// @param host Pointer to the new @c Host object being added.
     virtual void add(const HostPtr& host);
 
 private:
 
+    /// @brief Private default constructor.
+    HostMgr() { }
+
+    /// @brief Pointer to an alternate host data source.
+    ///
+    /// If this pointer is NULL, the source is not in use.
+    boost::scoped_ptr<BaseHostDataSource> alternate_source;
+
     /// @brief Returns a pointer to the currently used instance of the
     /// @c HostMgr.
     static boost::scoped_ptr<HostMgr>& getHostMgrPtr();
+
 };
 }
 }