content: //
  // Licensed to the Apache Software Foundation (ASF) under one
  // or more contributor license agreements.  See the NOTICE file
  // distributed with this work for additional information
  // regarding copyright ownership.  The ASF licenses this file
  // to you under the Apache License, Version 2.0 (the
  // "License"); you may not use this file except in compliance
  // with the License.  You may obtain a copy of the License at
  //
  //   http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing,
  // software distributed under the License is distributed on an
  // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  // KIND, either express or implied.  See the License for the
  // specific language governing permissions and limitations
  // under the License.
  //
  
  package com.cloud.hypervisor.kvm.resource.wrapper;
  
  import java.io.File;
  import java.text.MessageFormat;
  
  import org.libvirt.Connect;
  import org.libvirt.Domain;
  import org.libvirt.DomainInfo.DomainState;
  import org.libvirt.DomainSnapshot;
  import org.libvirt.LibvirtException;
  
  import com.ceph.rados.IoCTX;
  import com.ceph.rados.Rados;
  import com.ceph.rbd.Rbd;
  import com.ceph.rbd.RbdImage;
  import com.cloud.agent.api.Answer;
  import com.cloud.agent.api.ManageSnapshotAnswer;
  import com.cloud.agent.api.ManageSnapshotCommand;
  import com.cloud.agent.api.to.StorageFilerTO;
  import com.cloud.hypervisor.kvm.resource.LibvirtComputingResource;
  import com.cloud.hypervisor.kvm.storage.KVMPhysicalDisk;
  import com.cloud.hypervisor.kvm.storage.KVMStoragePool;
  import com.cloud.hypervisor.kvm.storage.KVMStoragePoolManager;
  import com.cloud.resource.CommandWrapper;
  import com.cloud.resource.ResourceWrapper;
  import com.cloud.storage.Storage.StoragePoolType;
  import com.cloud.utils.script.Script;
  
  @ResourceWrapper(handles =  ManageSnapshotCommand.class)
  public final class LibvirtManageSnapshotCommandWrapper extends CommandWrapper<ManageSnapshotCommand, Answer, LibvirtComputingResource> {
  
  
      @Override
      public Answer execute(final ManageSnapshotCommand command, final LibvirtComputingResource libvirtComputingResource) {
          final String snapshotName = command.getSnapshotName();
          final String snapshotPath = command.getSnapshotPath();
          final String vmName = command.getVmName();
          try {
              final LibvirtUtilitiesHelper libvirtUtilitiesHelper = libvirtComputingResource.getLibvirtUtilitiesHelper();
              final Connect conn = libvirtUtilitiesHelper.getConnectionByVmName(vmName);
              DomainState state = null;
              Domain vm = null;
              if (vmName != null) {
                  try {
                      vm = libvirtComputingResource.getDomain(conn, command.getVmName());
                      state = vm.getInfo().state;
                  } catch (final LibvirtException e) {
                      logger.trace("Ignoring libvirt error.", e);
                  }
              }
  
              final KVMStoragePoolManager storagePoolMgr = libvirtComputingResource.getStoragePoolMgr();
              final StorageFilerTO pool = command.getPool();
              final KVMStoragePool primaryPool = storagePoolMgr.getStoragePool(pool.getType(), pool.getUuid());
  
              final KVMPhysicalDisk disk = primaryPool.getPhysicalDisk(command.getVolumePath());
              if (state == DomainState.VIR_DOMAIN_RUNNING && !primaryPool.isExternalSnapshot()) {
  
                  final MessageFormat snapshotXML = new MessageFormat("   <domainsnapshot>" + "       <name>{0}</name>" + "          <domain>"
                          + "            <uuid>{1}</uuid>" + "        </domain>" + "    </domainsnapshot>");
  
                  final String vmUuid = vm.getUUIDString();
                  final Object[] args = new Object[] {snapshotName, vmUuid};
                  final String snapshot = snapshotXML.format(args);
                  logger.debug(snapshot);
                  if (command.getCommandSwitch().equalsIgnoreCase(ManageSnapshotCommand.CREATE_SNAPSHOT)) {
                      vm.snapshotCreateXML(snapshot);
                  } else {
                      final DomainSnapshot snap = vm.snapshotLookupByName(snapshotName);
                      snap.delete(0);
                  }
  
                  /*
                   * libvirt on RHEL6 doesn't handle resume event emitted from
                   * qemu
                   */
                  vm = libvirtComputingResource.getDomain(conn, command.getVmName());
                  state = vm.getInfo().state;
                  if (state == DomainState.VIR_DOMAIN_PAUSED) {
                      vm.resume();
                  }
              } else {
                  /**
                   * For RBD we can't use libvirt to do our snapshotting or any Bash scripts.
                   * libvirt also wants to store the memory contents of the Virtual Machine,
                   * but that's not possible with RBD since there is no way to store the memory
                   * contents in RBD.
                   *
                   * So we rely on the Java bindings for RBD to create our snapshot
                   *
                   * This snapshot might not be 100% consistent due to writes still being in the
                   * memory of the Virtual Machine, but if the VM runs a kernel which supports
                   * barriers properly (>2.6.32) this won't be any different then pulling the power
                   * cord out of a running machine.
                   */
                  if (primaryPool.getType() == StoragePoolType.RBD) {
                      try {
                          final Rados r = new Rados(primaryPool.getAuthUserName());
                          r.confSet("mon_host", primaryPool.getSourceHost() + ":" + primaryPool.getSourcePort());
                          r.confSet("key", primaryPool.getAuthSecret());
                          r.confSet("client_mount_timeout", "30");
                          r.connect();
                          logger.debug("Successfully connected to Ceph cluster at " + r.confGet("mon_host"));
  
                          final IoCTX io = r.ioCtxCreate(primaryPool.getSourceDir());
                          final Rbd rbd = new Rbd(io);
                          final RbdImage image = rbd.open(disk.getName());
  
                          if (command.getCommandSwitch().equalsIgnoreCase(ManageSnapshotCommand.CREATE_SNAPSHOT)) {
                              logger.debug("Attempting to create RBD snapshot " + disk.getName() + "@" + snapshotName);
                              image.snapCreate(snapshotName);
                          } else {
                              logger.debug("Attempting to remove RBD snapshot " + disk.getName() + "@" + snapshotName);
                              image.snapRemove(snapshotName);
                          }
  
                          rbd.close(image);
                          r.ioCtxDestroy(io);
                      } catch (final Exception e) {
                          logger.error("A RBD snapshot operation on " + disk.getName() + " failed. The error was: " + e.getMessage());
                      }
                  } else {
                      /* VM is not running, create a snapshot by ourself */
                      final int cmdsTimeout = libvirtComputingResource.getCmdsTimeout();
                      final String manageSnapshotPath = libvirtComputingResource.manageSnapshotPath();
  
                      final Script scriptCommand = new Script(manageSnapshotPath, cmdsTimeout, logger);
                      if (command.getCommandSwitch().equalsIgnoreCase(ManageSnapshotCommand.CREATE_SNAPSHOT)) {
                          scriptCommand.add("-c", disk.getPath());
                      } else {
                          scriptCommand.add("-d", snapshotPath);
                      }
  
                      scriptCommand.add("-n", snapshotName);
                      final String result = scriptCommand.execute();
                      if (result != null) {
                          logger.debug("Failed to manage snapshot: " + result);
                          return new ManageSnapshotAnswer(command, false, "Failed to manage snapshot: " + result);
                      }
                  }
              }
              return new ManageSnapshotAnswer(command, command.getSnapshotId(), disk.getPath() + File.separator + snapshotName, true, null);
          } catch (final LibvirtException e) {
              logger.debug("Failed to manage snapshot: " + e.toString());
              return new ManageSnapshotAnswer(command, false, "Failed to manage snapshot: " + e.toString());
          }
      }
  }
  