Kea  2.1.7-git
simple_remove.cc
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1 // Copyright (C) 2013-2022 Internet Systems Consortium, Inc. ("ISC")
2 //
3 // This Source Code Form is subject to the terms of the Mozilla Public
4 // License, v. 2.0. If a copy of the MPL was not distributed with this
5 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
6 
7 #include <config.h>
8 
9 #include <d2/simple_remove.h>
10 #include <d2srv/d2_cfg_mgr.h>
11 #include <d2srv/d2_log.h>
12 
13 #include <functional>
14 
15 namespace isc {
16 namespace d2 {
17 
18 
19 // SimpleRemoveTransaction states
22 
23 // SimpleRemoveTransaction events
24 // Currently SimpleRemoveTransaction does not define any events.
25 
29  DdnsDomainPtr& forward_domain,
30  DdnsDomainPtr& reverse_domain,
31  D2CfgMgrPtr& cfg_mgr)
32  : NameChangeTransaction(io_service, ncr, forward_domain, reverse_domain,
33  cfg_mgr) {
34  if (ncr->getChangeType() != isc::dhcp_ddns::CHG_REMOVE) {
36  "SimpleRemoveTransaction, request type must be CHG_REMOVE");
37  }
38 }
39 
41 }
42 
43 void
45  // Call superclass impl first.
47 
48  // Define SimpleRemoveTransaction events.
49  // Currently SimpleRemoveTransaction does not define any events.
50  // defineEvent(TBD_EVENT, "TBD_EVT");
51 }
52 
53 void
55  // Call superclass implementation first to verify its events. These are
56  // events common to all transactions, and they must be defined.
57  // SELECT_SERVER_EVT
58  // SERVER_SELECTED_EVT
59  // SERVER_IO_ERROR_EVT
60  // NO_MORE_SERVERS_EVT
61  // IO_COMPLETED_EVT
62  // UPDATE_OK_EVT
63  // UPDATE_FAILED_EVT
65 
66  // Verify SimpleRemoveTransaction events by attempting to fetch them.
67  // Currently SimpleRemoveTransaction does not define any events.
68  // getEvent(TBD_EVENT);
69 }
70 
71 void
73  // Call superclass impl first.
75 
76  // Define SimpleRemoveTransaction states.
77  defineState(READY_ST, "READY_ST",
78  std::bind(&SimpleRemoveTransaction::readyHandler, this));
79 
80  defineState(SELECTING_FWD_SERVER_ST, "SELECTING_FWD_SERVER_ST",
82  this));
83 
84  defineState(SELECTING_REV_SERVER_ST, "SELECTING_REV_SERVER_ST",
86  this));
87 
88  defineState(REMOVING_FWD_RRS_ST, "REMOVING_FWD_RRS_ST",
90  this));
91 
92  defineState(REMOVING_REV_PTRS_ST, "REMOVING_REV_PTRS_ST",
94  this));
95 
96  defineState(PROCESS_TRANS_OK_ST, "PROCESS_TRANS_OK_ST",
98  this));
99 
100  defineState(PROCESS_TRANS_FAILED_ST, "PROCESS_TRANS_FAILED_ST",
102  this));
103 }
104 
105 void
107  // Call superclass implementation first to verify its states. These are
108  // states common to all transactions, and they must be defined.
109  // READY_ST
110  // SELECTING_FWD_SERVER_ST
111  // SELECTING_REV_SERVER_ST
112  // PROCESS_TRANS_OK_ST
113  // PROCESS_TRANS_FAILED_ST
115 
116  // Verify SimpleRemoveTransaction states by attempting to fetch them.
119 }
120 
121 void
123  switch(getNextEvent()) {
124  case START_EVT:
125  if (getForwardDomain()) {
126  // Request includes a forward change, do that first.
128  } else {
129  // Reverse change only, transition accordingly.
131  }
132 
133  break;
134  default:
135  // Event is invalid.
137  "Wrong event for context: " << getContextStr());
138  }
139 }
140 
141 void
143  switch(getNextEvent()) {
144  case SELECT_SERVER_EVT:
145  // First time through for this transaction, so initialize server
146  // selection.
148  break;
149  case SERVER_IO_ERROR_EVT:
150  // We failed to communicate with current server. Attempt to select
151  // another one below.
152  break;
153  default:
154  // Event is invalid.
156  "Wrong event for context: " << getContextStr());
157  }
158 
159  // Select the next server from the list of forward servers.
160  if (selectNextServer()) {
161  // We have a server to try.
163  } else {
164  // Server list is exhausted, so fail the transaction.
166  }
167 }
168 
169 void
171  if (doOnEntry()) {
172  // Clear the update attempts count on initial transition.
174  }
175 
176  switch(getNextEvent()) {
177  case UPDATE_OK_EVT:
178  case SERVER_SELECTED_EVT:
179  try {
182  } catch (const std::exception& ex) {
183  // While unlikely, the build might fail if we have invalid
184  // data. Should that be the case, we need to fail the
185  // transaction.
188  .arg(getRequestId())
189  .arg(getNcr()->toText())
190  .arg(ex.what());
192  break;
193  }
194 
195  // Call sendUpdate() to initiate the async send. Note it also sets
196  // next event to NOP_EVT.
197  sendUpdate("Forward RR Remove");
198  break;
199 
200  case IO_COMPLETED_EVT: {
201  switch (getDnsUpdateStatus()) {
202  case DNSClient::SUCCESS: {
203  // We successfully received a response packet from the server.
204  // The RCODE will be based on a value-dependent RRset search,
205  // see RFC 2136 section 3.2.3/3.2.4.
206  const dns::Rcode& rcode = getDnsUpdateResponse()->getRcode();
207  if ((rcode == dns::Rcode::NOERROR()) ||
208  (rcode == dns::Rcode::NXRRSET())) {
209  // We were able to remove them or they were not there (
210  // Rcode of NXRRSET means there are no matching RRsets).
211  // In either case, we consider it success and mark it as done.
213 
214  // If request calls for reverse update then do that next,
215  // otherwise we can process ok.
216  if (getReverseDomain()) {
218  } else {
220  }
221  } else {
222  // Any other value means cease.
223  // If we get not authorized should try the next server in
224  // the list? @todo This needs some discussion perhaps.
226  .arg(getRequestId())
227  .arg(getCurrentServer()->toText())
228  .arg(getNcr()->getFqdn())
229  .arg(rcode.getCode());
231  }
232 
233  break;
234  }
235 
236  case DNSClient::TIMEOUT:
237  case DNSClient::OTHER:
238  // We couldn't send to the current server, log it and set up
239  // to select the next server for a retry.
240  // @note For now we treat OTHER as an IO error like TIMEOUT. It
241  // is not entirely clear if this is accurate.
243  .arg(getRequestId())
244  .arg(getNcr()->getFqdn())
245  .arg(getCurrentServer()->toText());
246 
248  break;
249 
251  // A response was received but was corrupt. Retry it like an IO
252  // error.
254  .arg(getRequestId())
255  .arg(getCurrentServer()->toText())
256  .arg(getNcr()->getFqdn());
257 
259  break;
260 
261  default:
262  // Any other value and we will fail this transaction, something
263  // bigger is wrong.
266  .arg(getRequestId())
267  .arg(getDnsUpdateStatus())
268  .arg(getNcr()->getFqdn())
269  .arg(getCurrentServer()->toText());
270 
272  break;
273  } // end switch on dns_status
274 
275  break;
276  } // end case IO_COMPLETE_EVT
277 
278  default:
279  // Event is invalid.
281  "Wrong event for context: " << getContextStr());
282  }
283 }
284 
285 void
287  switch(getNextEvent()) {
288  case SELECT_SERVER_EVT:
289  // First time through for this transaction, so initialize server
290  // selection.
292  break;
293  case SERVER_IO_ERROR_EVT:
294  // We failed to communicate with current server. Attempt to select
295  // another one below.
296  break;
297  default:
298  // Event is invalid.
300  "Wrong event for context: " << getContextStr());
301  }
302 
303  // Select the next server from the list of forward servers.
304  if (selectNextServer()) {
305  // We have a server to try.
307  } else {
308  // Server list is exhausted, so fail the transaction.
310  }
311 }
312 
313 
314 void
316  if (doOnEntry()) {
317  // Clear the update attempts count on initial transition.
319  }
320 
321  switch(getNextEvent()) {
322  case SERVER_SELECTED_EVT:
323  try {
326  } catch (const std::exception& ex) {
327  // While unlikely, the build might fail if we have invalid
328  // data. Should that be the case, we need to fail the
329  // transaction.
331  .arg(getRequestId())
332  .arg(getNcr()->toText())
333  .arg(ex.what());
335  break;
336  }
337 
338  // Call sendUpdate() to initiate the async send. Note it also sets
339  // next event to NOP_EVT.
340  sendUpdate("Reverse Remove");
341  break;
342 
343  case IO_COMPLETED_EVT: {
344  switch (getDnsUpdateStatus()) {
345  case DNSClient::SUCCESS: {
346  // We successfully received a response packet from the server.
347  // The RCODE will be based on a value-dependent RRset search,
348  // see RFC 2136 section 3.2.3/3.2.4.
349  const dns::Rcode& rcode = getDnsUpdateResponse()->getRcode();
350  if ((rcode == dns::Rcode::NOERROR()) ||
351  (rcode == dns::Rcode::NXRRSET())) {
352  // We were able to remove the reverse mapping or they were
353  // not there (Rcode of NXRRSET means there are no matching
354  // RRsets). In either case, mark it as done.
357  } else {
358  // Per RFC4703 any other value means cease.
359  // If we get not authorized should try the next server in
360  // the list? @todo This needs some discussion perhaps.
362  .arg(getRequestId())
363  .arg(getCurrentServer()->toText())
364  .arg(getNcr()->getFqdn())
365  .arg(rcode.getCode());
367  }
368 
369  break;
370  }
371 
372  case DNSClient::TIMEOUT:
373  case DNSClient::OTHER:
374  // We couldn't send to the current server, log it and set up
375  // to select the next server for a retry.
376  // @note For now we treat OTHER as an IO error like TIMEOUT. It
377  // is not entirely clear if this is accurate.
379  .arg(getRequestId())
380  .arg(getNcr()->getFqdn())
381  .arg(getCurrentServer()->toText());
382 
383  // If we are out of retries on this server, we go back and start
384  // all over on a new server.
386  break;
387 
389  // A response was received but was corrupt. Retry it like an IO
390  // error.
392  .arg(getRequestId())
393  .arg(getCurrentServer()->toText())
394  .arg(getNcr()->getFqdn());
395 
396  // If we are out of retries on this server, we go back and start
397  // all over on a new server.
399  break;
400 
401  default:
402  // Any other value and we will fail this transaction, something
403  // bigger is wrong.
406  .arg(getRequestId())
407  .arg(getDnsUpdateStatus())
408  .arg(getNcr()->getFqdn())
409  .arg(getCurrentServer()->toText());
410 
412  break;
413  } // end switch on dns_status
414 
415  break;
416  } // end case IO_COMPLETE_EVT
417 
418  default:
419  // Event is invalid.
421  "Wrong event for context: " << getContextStr());
422  }
423 }
424 
425 
426 void
428  switch(getNextEvent()) {
429  case UPDATE_OK_EVT:
431  .arg(getRequestId())
432  .arg(getNcr()->toText());
434  endModel();
435  break;
436  default:
437  // Event is invalid.
439  "Wrong event for context: " << getContextStr());
440  }
441 }
442 
443 void
445  switch(getNextEvent()) {
446  case UPDATE_FAILED_EVT:
447  case NO_MORE_SERVERS_EVT:
448  case SERVER_IO_ERROR_EVT:
451  .arg(getRequestId())
452  .arg(transactionOutcomeString());
453  endModel();
454  break;
455  default:
456  // Event is invalid.
458  "Wrong event for context: " << getContextStr());
459  }
460 }
461 
462 void
464  // Construct an empty request.
466 
467  // There are no pre-requisites.
468 
469  // Build the Update Section
470  // Construct dns::Name from NCR fqdn.
471  dns::Name fqdn(dns::Name(getNcr()->getFqdn()));
472 
473  // Build the Update Section.
474 
475  // Create the FQDN/IP 'delete' RR and add it to update section.
476  dns::RRsetPtr update(new dns::RRset(fqdn, dns::RRClass::ANY(),
478 
479  request->addRRset(D2UpdateMessage::SECTION_UPDATE, update);
480 
481  // Create the DHCID 'delete' RR and add it to the update section.
482  update.reset(new dns::RRset(fqdn, dns::RRClass::ANY(),
484  request->addRRset(D2UpdateMessage::SECTION_UPDATE, update);
485 
486  // Set the transaction's update request to the new request.
487  setDnsUpdateRequest(request);
488 }
489 
490 void
492  // Construct an empty request.
494 
495  // Create the reverse IP address "FQDN".
496  std::string rev_addr = D2CfgMgr::reverseIpAddress(getNcr()->getIpAddress());
497  dns::Name rev_ip(rev_addr);
498 
499  // There are no pre-requisites.
500 
501  // Build the Update section.
502 
503  // Create the FQDN/IP PTR 'delete' RR for this IP and add it to
504  // the update section.
505  dns::RRsetPtr update(new dns::RRset(rev_ip, dns::RRClass::ANY(),
507  request->addRRset(D2UpdateMessage::SECTION_UPDATE, update);
508 
509  // Create the DHCID 'delete' RR and add it to the update section.
510  update.reset(new dns::RRset(rev_ip, dns::RRClass::ANY(),
512  request->addRRset(D2UpdateMessage::SECTION_UPDATE, update);
513 
514  // Set the transaction's update request to the new request.
515  setDnsUpdateRequest(request);
516 }
517 
518 } // namespace isc::d2
519 } // namespace isc
void defineState(unsigned int value, const std::string &label, StateHandler handler, const StatePausing &state_pausing=STATE_PAUSE_NEVER)
Adds an state value and associated label to the set of states.
Definition: state_model.cc:196
virtual D2UpdateMessagePtr prepNewRequest(DdnsDomainPtr domain)
Creates a new DNS update request based on the given domain.
Definition: nc_trans.cc:343
The Name class encapsulates DNS names.
Definition: name.h:223
const isc::log::MessageID DHCP_DDNS_FORWARD_REMOVE_RRS_IO_ERROR
Definition: d2_messages.h:35
virtual void sendUpdate(const std::string &comment="")
Send the update request to the current server.
Definition: nc_trans.cc:192
static const RRType & DHCID()
Definition: rrtype.h:503
const isc::log::MessageID DHCP_DDNS_FORWARD_REMOVE_RRS_REJECTED
Definition: d2_messages.h:36
virtual void verifyStates()
Validates the contents of the set of states.
static const int PROCESS_TRANS_OK_ST
State which processes successful transaction conclusion.
Definition: nc_trans.h:102
void processRemoveOkHandler()
State handler for PROCESS_TRANS_OK_ST.
void selectingFwdServerHandler()
State handler for SELECTING_FWD_SERVER_ST.
std::string getContextStr() const
Convenience method which returns a string rendition of the current state and next event...
Definition: state_model.cc:443
static const int REMOVING_REV_PTRS_ST
State that attempts to remove reverse PTR records.
Definition: simple_remove.h:57
virtual ~SimpleRemoveTransaction()
Destructor.
static const RRType & PTR()
Definition: rrtype.h:443
#define LOG_INFO(LOGGER, MESSAGE)
Macro to conveniently test info output and log it.
Definition: macros.h:20
static std::string reverseIpAddress(const std::string &address)
Generate a reverse order string for the given IP address.
Definition: d2_cfg_mgr.cc:170
void readyHandler()
State handler for READY_ST.
boost::shared_ptr< DdnsDomain > DdnsDomainPtr
Defines a pointer for DdnsDomain instances.
Definition: d2_config.h:612
static const Rcode & NOERROR()
A constant object for the NOERROR Rcode (see Rcode::NOERROR_CODE).
Definition: rcode.h:220
const dhcp_ddns::NameChangeRequestPtr & getNcr() const
Fetches the NameChangeRequest for this transaction.
Definition: nc_trans.cc:425
boost::shared_ptr< D2UpdateMessage > D2UpdateMessagePtr
Pointer to the DNS Update Message.
void setNcrStatus(const dhcp_ddns::NameChangeStatus &status)
Sets the status of the transaction&#39;s NameChangeRequest.
Definition: nc_trans.cc:538
static const int START_EVT
Event issued to start the model execution.
Definition: state_model.h:295
const isc::log::MessageID DHCP_DDNS_REVERSE_REMOVE_IO_ERROR
Definition: d2_messages.h:70
#define LOG_ERROR(LOGGER, MESSAGE)
Macro to conveniently test error output and log it.
Definition: macros.h:32
No response, timeout.
Definition: dns_client.h:60
static const int SELECTING_FWD_SERVER_ST
State in which forward DNS server selection is done.
Definition: nc_trans.h:91
DNS Response Codes (RCODEs) class.
Definition: rcode.h:40
static const int REMOVING_FWD_RRS_ST
State that attempts to remove FQDN/IP and DHCID RRs for an FQDN.
Definition: simple_remove.h:54
boost::shared_ptr< NameChangeRequest > NameChangeRequestPtr
Defines a pointer to a NameChangeRequest.
Definition: ncr_msg.h:212
void endModel()
Conducts a normal transition to the end of the model.
Definition: state_model.cc:271
static const int SERVER_IO_ERROR_EVT
Issued when an update fails due to an IO error.
Definition: nc_trans.h:119
void selectingRevServerHandler()
State handler for SELECTING_REV_SERVER_ST.
static const int IO_COMPLETED_EVT
Issued when a DNS update packet exchange has completed.
Definition: nc_trans.h:130
const DnsServerInfoPtr & getCurrentServer() const
Fetches the currently selected server.
Definition: nc_trans.cc:533
SimpleRemoveTransaction(asiolink::IOServicePtr &io_service, dhcp_ddns::NameChangeRequestPtr &ncr, DdnsDomainPtr &forward_domain, DdnsDomainPtr &reverse_domain, D2CfgMgrPtr &cfg_mgr)
Event sent when replace attempt to fails with address not in use.
Other, unclassified error.
Definition: dns_client.h:63
#define isc_throw(type, stream)
A shortcut macro to insert known values into exception arguments.
void setForwardChangeCompleted(const bool value)
Sets the forward change completion flag to the given value.
Definition: nc_trans.cc:328
isc::log::Logger d2_to_dns_logger("d2-to-dns")
Definition: d2_log.h:20
const isc::log::MessageID DHCP_DDNS_FORWARD_REMOVE_RRS_BUILD_FAILURE
Definition: d2_messages.h:34
static const int SERVER_SELECTED_EVT
Issued when a server has been selected.
Definition: nc_trans.h:116
Thrown if the SimpleRemoveTransaction encounters a general error.
Definition: simple_remove.h:18
void retryTransition(const int fail_to_state)
Determines the state and next event based on update attempts.
Definition: nc_trans.cc:286
virtual void defineEvents()
Adds events defined by SimpleRemoveTransaction to the event set.
const isc::log::MessageID DHCP_DDNS_FORWARD_REMOVE_RRS_RESP_CORRUPT
Definition: d2_messages.h:37
bool doOnEntry()
Checks if on entry flag is true.
Definition: state_model.cc:339
void buildRemoveFwdRRsRequest()
Builds a DNS request to remove all forward DNS RRs for a FQDN.
const isc::log::MessageID DHCP_DDNS_FORWARD_REMOVE_RRS_BAD_DNSCLIENT_STATUS
Definition: d2_messages.h:33
const isc::log::MessageID DHCP_DDNS_REVERSE_REMOVE_BUILD_FAILURE
Definition: d2_messages.h:69
boost::shared_ptr< D2CfgMgr > D2CfgMgrPtr
Defines a shared pointer to D2CfgMgr.
Definition: d2_cfg_mgr.h:334
const dns::RRType & getAddressRRType() const
Returns the DHCP data type for the lease address.
Definition: nc_trans.cc:573
virtual void defineStates()
Adds states defined by NameChangeTransaction to the state set.
Definition: nc_trans.cc:257
The RRTTL class encapsulates TTLs used in DNS resource records.
Definition: rrttl.h:55
unsigned int getNextEvent() const
Fetches the model&#39;s next event.
Definition: state_model.cc:373
void setReverseChangeCompleted(const bool value)
Sets the reverse change completion flag to the given value.
Definition: nc_trans.cc:333
const isc::log::MessageID DHCP_DDNS_REVERSE_REMOVE_BAD_DNSCLIENT_STATUS
Definition: d2_messages.h:68
Response received and is ok.
Definition: dns_client.h:59
static const RRClass & ANY()
Definition: rrclass.h:301
static const int SELECTING_REV_SERVER_ST
State in which reverse DNS server selection is done.
Definition: nc_trans.h:99
DdnsDomainPtr & getForwardDomain()
Fetches the forward DdnsDomain.
Definition: nc_trans.cc:445
const isc::log::MessageID DHCP_DDNS_REVERSE_REMOVE_RESP_CORRUPT
Definition: d2_messages.h:72
void clearUpdateAttempts()
Resets the update attempts count.
Definition: nc_trans.cc:308
Defines the logger used by the top-level component of kea-lfc.
static const int NO_MORE_SERVERS_EVT
Issued when there are no more servers from which to select.
Definition: nc_trans.h:125
std::string getRequestId() const
Fetches the request id that identifies this transaction.
Definition: nc_trans.cc:435
void transition(unsigned int state, unsigned int event)
Sets up the model to transition into given state with a given event.
Definition: state_model.cc:264
DNSClient::Status getDnsUpdateStatus() const
Fetches the most recent DNS update status.
Definition: nc_trans.cc:548
The RRset class is a concrete derived class of BasicRRset which contains a pointer to an additional R...
Definition: rrset.h:847
Response received but invalid.
Definition: dns_client.h:62
const isc::log::MessageID DHCP_DDNS_REMOVE_SUCCEEDED
Definition: d2_messages.h:66
static const int PROCESS_TRANS_FAILED_ST
State which processes an unsuccessful transaction conclusion.
Definition: nc_trans.h:105
std::string transactionOutcomeString() const
Returns a string version of transaction outcome.
Definition: nc_trans.cc:170
const isc::log::MessageID DHCP_DDNS_REMOVE_FAILED
Definition: d2_messages.h:65
void buildRemoveRevPtrsRequest()
Builds a DNS request to remove a reverse DNS entry for a FQDN.
static const int SELECT_SERVER_EVT
Issued when a server needs to be selected.
Definition: nc_trans.h:113
void clearDnsUpdateRequest()
Destroys the current update request packet.
Definition: nc_trans.cc:303
static const int READY_ST
State from which a transaction is started.
Definition: nc_trans.h:83
void setDnsUpdateRequest(D2UpdateMessagePtr &request)
Sets the update request packet to the given packet.
Definition: nc_trans.cc:298
const isc::log::MessageID DHCP_DDNS_REVERSE_REMOVE_REJECTED
Definition: d2_messages.h:71
virtual void defineEvents()
Adds events defined by NameChangeTransaction to the event set.
Definition: nc_trans.cc:227
Embodies the "life-cycle" required to carry out a DDNS update.
Definition: nc_trans.h:77
const StatePtr getStateInternal(unsigned int value)
Fetches the state referred to by value.
Definition: state_model.cc:219
static const int UPDATE_OK_EVT
Issued when the attempted update successfully completed.
Definition: nc_trans.h:135
void removingRevPtrsHandler()
State handler for REMOVING_REV_PTRS_ST.
boost::shared_ptr< AbstractRRset > RRsetPtr
A pointer-like type pointing to an RRset object.
Definition: rrset.h:47
void removingFwdRRsHandler()
State handler for REMOVING_FWD_RRS_ST.
DdnsDomainPtr & getReverseDomain()
Fetches the reverse DdnsDomain.
Definition: nc_trans.cc:450
static const int UPDATE_FAILED_EVT
Issued when the attempted update fails to complete.
Definition: nc_trans.h:141
virtual void verifyEvents()
Validates the contents of the set of events.
Definition: nc_trans.cc:242
static const Rcode & NXRRSET()
A constant object for the NXRRSET Rcode (see Rcode::NXRRSET_CODE).
Definition: rcode.h:268
void processRemoveFailedHandler()
State handler for PROCESS_TRANS_FAILED_ST.
virtual void defineStates()
Adds states defined by SimpleRemoveTransaction to the state set.
const D2UpdateMessagePtr & getDnsUpdateResponse() const
Fetches the most recent DNS update response packet.
Definition: nc_trans.cc:553
void initServerSelection(const DdnsDomainPtr &domain)
Initializes server selection from the given DDNS domain.
Definition: nc_trans.cc:455
uint16_t getCode() const
Returns the Rcode code value.
Definition: rcode.h:106
virtual void verifyEvents()
Validates the contents of the set of events.
bool selectNextServer()
Selects the next server in the current server list.
Definition: nc_trans.cc:467
virtual void verifyStates()
Validates the contents of the set of states.
Definition: nc_trans.cc:265