[qemu/platform] Add plumbing for getting networks

src/platform/backends/qemu/qemu_platform.h

@@ -19,7 +19,9 @@
 #define MULTIPASS_QEMU_PLATFORM_H
 
 #include <multipass/disabled_copy_move.h>
+#include <multipass/exceptions/not_implemented_on_this_backend_exception.h>
 #include <multipass/ip_address.h>
+#include <multipass/network_interface_info.h>
 #include <multipass/optional.h>
 #include <multipass/path.h>
 #include <multipass/singleton.h>
@@ -52,6 +54,10 @@ class QemuPlatform : private DisabledCopyMove
     {
         return {};
     };
+    virtual std::vector<NetworkInterfaceInfo> networks() const
+    {
+        throw NotImplementedOnThisBackendException("networks");
+    };
 
 protected:
     explicit QemuPlatform() = default;

src/platform/backends/qemu/qemu_virtual_machine_factory.cpp

@@ -113,3 +113,8 @@ QString mp::QemuVirtualMachineFactory::get_backend_directory_name()
 {
     return qemu_platform->get_directory_name();
 }
+
+auto mp::QemuVirtualMachineFactory::networks() const -> std::vector<NetworkInterfaceInfo>
+{
+    return qemu_platform->networks();
+}

src/platform/backends/qemu/qemu_virtual_machine_factory.h

@@ -41,6 +41,7 @@ class QemuVirtualMachineFactory final : public BaseVirtualMachineFactory
     void hypervisor_health_check() override;
     QString get_backend_version_string() override;
     QString get_backend_directory_name() override;
+    std::vector<NetworkInterfaceInfo> networks() const override;
 
 private:
     QemuPlatform::UPtr qemu_platform;