Introduces callbacks into the LeaseMgr. More...

#include <tracking_lease_mgr.h>

Inheritance diagram for isc::dhcp::TrackingLeaseMgr:

Classes
struct	Callback
	A structure representing a registered callback. More...

Public Types
typedef std::function< void(LeasePtr)>	CallbackFn
	Type of a callback function invoked upon a lease insertion, update or deletion.

enum	CallbackType { TRACK_ADD_LEASE , TRACK_UPDATE_LEASE , TRACK_DELETE_LEASE }
	An enumeration differentiating between lease write operations. More...

Public Member Functions
bool	hasCallbacks () const
	Checks if any callbacks have been registered.

bool	isLocked (const LeasePtr &lease)
	Checks if the lease is locked.

void	registerCallback (CallbackType type, std::string owner, Lease::Type lease_type, CallbackFn callback_fn)
	Registers a callback function for all subnets.

void	registerCallback (CallbackType type, std::string owner, SubnetID subnet_id, Lease::Type lease_type, CallbackFn callback_fn)
	Registers a callback function for a subnet.

void	unregisterAllCallbacks ()
	Unregisters all callbacks.

void	unregisterCallbacks (SubnetID subnet_id, Lease::Type lease_type)
	Unregisters all callbacks for a given subnet identifier.

Public Member Functions inherited from isc::dhcp::LeaseMgr
	LeaseMgr ()
	Constructor.

virtual	~LeaseMgr ()
	Destructor.

virtual bool	addLease (const Lease4Ptr &lease)=0
	Adds an IPv4 lease.

virtual bool	addLease (const Lease6Ptr &lease)=0
	Adds an IPv6 lease.

virtual size_t	byRelayId6size () const
	Return the by-relay-id table size.

virtual size_t	byRemoteId6size () const
	Return the by-remote-id table size.

virtual std::string	checkLimits4 (isc::data::ConstElementPtr const &user_context) const =0
	Checks if the IPv4 lease limits set in the given user context are exceeded.

virtual std::string	checkLimits6 (isc::data::ConstElementPtr const &user_context) const =0
	Checks if the IPv6 lease limits set in the given user context are exceeded.

virtual void	clearClassLeaseCounts ()=0
	Clears the class-lease count map.

virtual void	commit ()=0
	Commit Transactions.

virtual uint64_t	deleteExpiredReclaimedLeases4 (const uint32_t secs)=0
	Deletes all expired and reclaimed DHCPv4 leases.

virtual uint64_t	deleteExpiredReclaimedLeases6 (const uint32_t secs)=0
	Deletes all expired and reclaimed DHCPv6 leases.

virtual bool	deleteLease (const Lease4Ptr &lease)=0
	Deletes an IPv4 lease.

virtual bool	deleteLease (const Lease6Ptr &lease)=0
	Deletes an IPv6 lease.

virtual size_t	getClassLeaseCount (const ClientClass &client_class, const Lease::Type &ltype=Lease::TYPE_V4) const =0
	Returns the class lease count for a given class and lease type.

virtual std::string	getDescription () const =0
	Returns description of the backend.

virtual void	getExpiredLeases4 (Lease4Collection &expired_leases, const size_t max_leases) const =0
	Returns a collection of expired DHCPv4 leases.

virtual void	getExpiredLeases6 (Lease6Collection &expired_leases, const size_t max_leases) const =0
	Returns a collection of expired DHCPv6 leases.

bool	getExtendedInfoTablesEnabled () const
	Returns the setting indicating if lease6 extended info tables are enabled.

virtual Lease4Collection	getLease4 (const ClientId &clientid) const =0
	Returns existing IPv4 lease for specified client-id.

virtual Lease4Ptr	getLease4 (const ClientId &clientid, SubnetID subnet_id) const =0
	Returns existing IPv4 lease for specified client-id.

virtual Lease4Ptr	getLease4 (const isc::asiolink::IOAddress &addr) const =0
	Returns an IPv4 lease for specified IPv4 address.

virtual Lease4Collection	getLease4 (const isc::dhcp::HWAddr &hwaddr) const =0
	Returns existing IPv4 leases for specified hardware address.

virtual Lease4Ptr	getLease4 (const isc::dhcp::HWAddr &hwaddr, SubnetID subnet_id) const =0
	Returns existing IPv4 leases for specified hardware address and a subnet.

Lease6Ptr	getLease6 (Lease::Type type, const DUID &duid, uint32_t iaid, SubnetID subnet_id) const
	returns zero or one IPv6 lease for a given duid+iaid+subnet_id

virtual Lease6Ptr	getLease6 (Lease::Type type, const isc::asiolink::IOAddress &addr) const =0
	Returns existing IPv6 lease for a given IPv6 address.

virtual Lease4Collection	getLeases4 () const =0
	Returns all IPv4 leases.

virtual Lease4Collection	getLeases4 (const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size) const =0
	Returns range of IPv4 leases using paging.

virtual Lease4Collection	getLeases4 (const std::string &hostname) const =0
	Returns all IPv4 leases for the particular hostname.

virtual Lease4Collection	getLeases4 (SubnetID subnet_id) const =0
	Returns all IPv4 leases for the particular subnet identifier.

virtual Lease4Collection	getLeases4ByRelayId (const OptionBuffer &relay_id, const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size, const time_t &qry_start_time=0, const time_t &qry_end_time=0)=0
	Returns existing IPv4 leases with a given relay-id.

virtual Lease4Collection	getLeases4ByRemoteId (const OptionBuffer &remote_id, const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size, const time_t &qry_start_time=0, const time_t &qry_end_time=0)=0
	Returns existing IPv4 leases with a given remote-id.

virtual Lease6Collection	getLeases6 () const =0
	Returns all IPv6 leases.

virtual Lease6Collection	getLeases6 (const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size) const =0
	Returns range of IPv6 leases using paging.

virtual Lease6Collection	getLeases6 (const DUID &duid) const =0
	Returns collection of leases for matching DUID.

virtual Lease6Collection	getLeases6 (const std::string &hostname) const =0
	Returns all IPv6 leases for the particular hostname.

virtual Lease6Collection	getLeases6 (Lease::Type type, const DUID &duid, uint32_t iaid) const =0
	Returns existing IPv6 leases for a given DUID+IA combination.

virtual Lease6Collection	getLeases6 (Lease::Type type, const DUID &duid, uint32_t iaid, SubnetID subnet_id) const =0
	Returns existing IPv6 lease for a given DUID+IA combination.

virtual Lease6Collection	getLeases6 (SubnetID subnet_id) const =0
	Returns all IPv6 leases for the particular subnet identifier.

virtual Lease6Collection	getLeases6 (SubnetID subnet_id, const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size) const =0
	Returns a page of IPv6 leases for a subnet identifier.

virtual Lease6Collection	getLeases6ByRelayId (const DUID &relay_id, const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size)=0
	Returns existing IPv6 leases with a given relay-id.

virtual Lease6Collection	getLeases6ByRemoteId (const OptionBuffer &remote_id, const asiolink::IOAddress &lower_bound_address, const LeasePageSize &page_size)=0
	Returns existing IPv6 leases with a given remote-id.

virtual std::string	getName () const =0
	Returns backend name.

virtual std::string	getType () const =0
	Return backend type.

virtual VersionPair	getVersion (const std::string &timer_name=std::string()) const =0
	Returns backend version.

virtual bool	isJsonSupported () const =0
	Checks if JSON support is enabled in the database.

virtual void	recountClassLeases4 ()=0
	Recount the leases per class for V4 leases.

virtual void	recountClassLeases6 ()=0
	Recount the leases per class for V6 leases.

void	recountLeaseStats4 ()
	Recalculates per-subnet and global stats for IPv4 leases.

void	recountLeaseStats6 ()
	Recalculates per-subnet and global stats for IPv6 leases.

virtual void	rollback ()=0
	Rollback Transactions.

void	setExtendedInfoTablesEnabled (const bool enabled)
	Modifies the setting whether the lease6 extended info tables are enabled.

virtual LeaseStatsQueryPtr	startLeaseStatsQuery4 ()
	Creates and runs the IPv4 lease stats query for all subnets.

virtual LeaseStatsQueryPtr	startLeaseStatsQuery6 ()
	Creates and runs the IPv6 lease stats query for all subnets.

virtual LeaseStatsQueryPtr	startPoolLeaseStatsQuery4 ()
	Creates and runs the IPv4 lease stats query for all subnets and pools.

virtual LeaseStatsQueryPtr	startPoolLeaseStatsQuery6 ()
	Creates and runs the IPv6 lease stats query for all subnets and pools.

virtual LeaseStatsQueryPtr	startSubnetLeaseStatsQuery4 (const SubnetID &subnet_id)
	Creates and runs the IPv4 lease stats query for a single subnet.

virtual LeaseStatsQueryPtr	startSubnetLeaseStatsQuery6 (const SubnetID &subnet_id)
	Creates and runs the IPv6 lease stats query for a single subnet.

virtual LeaseStatsQueryPtr	startSubnetRangeLeaseStatsQuery4 (const SubnetID &first_subnet_id, const SubnetID &last_subnet_id)
	Creates and runs the IPv4 lease stats query for a single subnet.

virtual LeaseStatsQueryPtr	startSubnetRangeLeaseStatsQuery6 (const SubnetID &first_subnet_id, const SubnetID &last_subnet_id)
	Creates and runs the IPv6 lease stats query for a single subnet.

virtual void	updateLease4 (const Lease4Ptr &lease4)=0
	Updates IPv4 lease.

virtual void	updateLease6 (const Lease6Ptr &lease6)=0
	Updates IPv6 lease.

virtual size_t	upgradeExtendedInfo4 (const LeasePageSize &page_size)=0
	Upgrade extended info (v4).

virtual size_t	upgradeExtendedInfo6 (const LeasePageSize &page_size)=0
	Upgrade extended info (v6).

virtual void	wipeExtendedInfoTables6 ()=0
	Wipe extended info table (v6).

virtual size_t	wipeLeases4 (const SubnetID &subnet_id)=0
	Virtual method which removes specified leases.

virtual size_t	wipeLeases6 (const SubnetID &subnet_id)=0
	Virtual method which removes specified leases.

virtual void	writeLeases4 (const std::string &filename)=0
	Write V4 leases to a file.

virtual void	writeLeases6 (const std::string &filename)=0
	Write V6 leases to a file.

Protected Types
typedef boost::multi_index_container< Callback, boost::multi_index::indexed_by< boost::multi_index::ordered_non_unique< boost::multi_index::composite_key< Callback, boost::multi_index::member< Callback, CallbackType, &Callback::type >, boost::multi_index::member< Callback, SubnetID, &Callback::subnet_id >, boost::multi_index::member< Callback, Lease::Type, &Callback::lease_type > > >, boost::multi_index::ordered_non_unique< boost::multi_index::composite_key< Callback, boost::multi_index::member< Callback, SubnetID, &Callback::subnet_id >, boost::multi_index::member< Callback, Lease::Type, &Callback::lease_type > > > > >	CallbackContainer
	A multi-index container holding registered callbacks.

typedef boost::shared_ptr< CallbackContainer >	CallbackContainerPtr
	Pointer to the callback container.

Protected Member Functions
	TrackingLeaseMgr ()
	Constructor.

void	runCallbacks (CallbackType type, const LeasePtr &lease)
	Runs registered callbacks of the particular type.

void	runCallbacksForSubnetID (CallbackType type, SubnetID subnet_id, const LeasePtr &lease)
	Runs registered callbacks of the particular type for a subnet id.

void	trackAddLease (const LeasePtr &lease)
	Invokes the callbacks when a new lease is added.

void	trackDeleteLease (const LeasePtr &lease)
	Invokes the callbacks when a lease is deleted.

void	trackUpdateLease (const LeasePtr &lease)
	Invokes the callbacks when a lease is updated.

bool	tryLock (const LeasePtr &lease)
	Attempts to lock a lease.

void	unlock (const LeasePtr &lease)
	Attempts to unlock a lease.

Protected Member Functions inherited from isc::dhcp::LeaseMgr
virtual bool	addExtendedInfo6 (const Lease6Ptr &lease)
	Extract extended info from a lease6 and add it into tables.

virtual void	addRelayId6 (const isc::asiolink::IOAddress &lease_addr, const std::vector< uint8_t > &relay_id)=0
	Add lease6 extended info into by-relay-id table.

virtual void	addRemoteId6 (const isc::asiolink::IOAddress &lease_addr, const std::vector< uint8_t > &remote_id)=0
	Add lease6 extended info into by-remote-id table.

virtual void	deleteExtendedInfo6 (const isc::asiolink::IOAddress &addr)=0
	Delete lease6 extended info from tables.

void	setExtendedInfoTablesEnabled (const db::DatabaseConnection::ParameterMap &parameters)
	Extended information / Bulk Lease Query shared interface.

Static Protected Member Functions
static std::string	callbackTypeToString (CallbackType type)
	Converts callback type to string for logging purposes.

Protected Attributes
CallbackContainerPtr	callbacks_
	The multi-index container holding registered callbacks.

std::unordered_set< asiolink::IOAddress, asiolink::IOAddress::Hash >	locked_leases_
	A set of locked leases.

Friends
class	LeaseMgrFactory
	The `LeaseMgrFactory` manages the `LeaseMgr` instances and has to be able to move installed callbacks between them.

Additional Inherited Members
Static Public Member Functions inherited from isc::dhcp::LeaseMgr
static void	extractLease4ExtendedInfo (const Lease4Ptr &lease, bool ignore_errors=true)
	Extract relay and remote identifiers from the extended info.

static std::string	getDBVersion ()
	Class method to return extended version info This class method must be redeclared and redefined in derived classes.

static bool	upgradeLease4ExtendedInfo (const Lease4Ptr &lease, CfgConsistency::ExtendedInfoSanity check=CfgConsistency::EXTENDED_INFO_CHECK_FIX)
	The following queries are used to fulfill Bulk Lease Query queries.

static bool	upgradeLease6ExtendedInfo (const Lease6Ptr &lease, CfgConsistency::ExtendedInfoSanity check=CfgConsistency::EXTENDED_INFO_CHECK_FIX)
	Upgrade a V6 lease user context to the new extended info entry.

Detailed Description

Introduces callbacks into the LeaseMgr.

The LeaseMgr is a central point of lease management and is aware of all lease changes within the server instance. Thus, it is a good opportunity to allow installing callbacks in the LeaseMgr to track all lease changes. An allocator maintaining a list of free leases (FLQ allocator) can benefit from it by/ installing the callbacks that add or remove free leases from this list, depending on the lease manager's activity. The callbacks are invoked regardless if the lease changes result from a normal lease allocation or a control command. The callbacks can also be useful for maintaining a log of lease changes. Such a log could be made available externally and consumed by another application (e.g., Stork).

The lease manager can track three types of calls: new lease insertion (add), an existing lease update, and lease deletion. Even though the lease reclamation is similar to deleting a lease because it becomes free, it is a lease update from the lease manager's standpoint. Currently, the lease manager cannot track the deletion of the reclaimed leases (i.e., the leases in the expired-reclaimed state).

The lease backends should call the suitable tracking functions: trackAddLease, trackUpdateLease, and trackDeleteLease. However, the backends must ensure that there are no race conditions between modifying the lease in the database and running the callbacks. Suppose that two threads modify the same lease. Thread A inserts the lease in the database, and thread B removes it. The callback for thread A should be invoked before the callback for thread B. If they are invoked in reverse order, it can result in an inconsistent state in the free lease queue allocator because the allocator should record the lease as available after the thread B callback. The reverse invocation order would result in marking the lease as unavailable for allocation after both callbacks.

The race condition does not occur for the Memfile backend because it guards entire functions with a mutex. However, the SQL backends rely on the database to guard against concurrent writes. In these cases, the backend must protect against the reverse order of callbacks. They should use the lease locking mechanism introduced in the TrackingLeaseMgr.

The lease locking is modeled on an unordered_set container holding the leases with the ongoing allocations. The leases are inserted into this container by the tryLock function. If another thread has already locked the lease, this function returns false to indicate an unsuccessful attempt. In this case, the thread should resign from updating the lease and return early. It can result in a lease allocation failure, but two concurrent threads extremely rarely work on allocating a lease for the same client. A passive wait could be another option here, but it is a much more complicated solution for a bit of gain.

Definition at line 76 of file tracking_lease_mgr.h.

Member Typedef Documentation

◆ CallbackContainer

typedef boost::multi_index_container< Callback, boost::multi_index::indexed_by< boost::multi_index::ordered_non_unique< boost::multi_index::composite_key< Callback, boost::multi_index::member<Callback, CallbackType, &Callback::type>, boost::multi_index::member<Callback, SubnetID, &Callback::subnet_id>, boost::multi_index::member<Callback, Lease::Type, &Callback::lease_type> > >, boost::multi_index::ordered_non_unique< boost::multi_index::composite_key< Callback, boost::multi_index::member<Callback, SubnetID, &Callback::subnet_id>, boost::multi_index::member<Callback, Lease::Type, &Callback::lease_type> > > > > isc::dhcp::TrackingLeaseMgr::CallbackContainer

protected

A multi-index container holding registered callbacks.

The callbacks are accessible via two indexes. The first composite index filters the callbacks by the callback type (i.e., lease add, update or delete) and the subnet id. The second index filters the callbacks by the subnet id and the lease type.

Definition at line 150 of file tracking_lease_mgr.h.

◆ CallbackContainerPtr

typedef boost::shared_ptr<CallbackContainer> isc::dhcp::TrackingLeaseMgr::CallbackContainerPtr

protected

Pointer to the callback container.

Definition at line 153 of file tracking_lease_mgr.h.

◆ CallbackFn

typedef std::function<void(LeasePtr)> isc::dhcp::TrackingLeaseMgr::CallbackFn

Type of a callback function invoked upon a lease insertion, update or deletion.

The first argument is a pointer to the lease for which the callback is invoked.

Definition at line 97 of file tracking_lease_mgr.h.

Member Enumeration Documentation

◆ CallbackType

enum isc::dhcp::TrackingLeaseMgr::CallbackType

An enumeration differentiating between lease write operations.

Enumerator
TRACK_ADD_LEASE
TRACK_UPDATE_LEASE
TRACK_DELETE_LEASE

Definition at line 86 of file tracking_lease_mgr.h.

Constructor & Destructor Documentation

◆ TrackingLeaseMgr()

isc::dhcp::TrackingLeaseMgr::TrackingLeaseMgr ( )

protected

Constructor.

Definition at line 22 of file tracking_lease_mgr.cc.

Member Function Documentation

◆ callbackTypeToString()

std::string isc::dhcp::TrackingLeaseMgr::callbackTypeToString ( CallbackType type )

staticprotected

Converts callback type to string for logging purposes.

Parameters

type	callback type.

Returns: callback type name or the 'unknown' string.

Definition at line 114 of file tracking_lease_mgr.cc.

References TRACK_ADD_LEASE, TRACK_DELETE_LEASE, and TRACK_UPDATE_LEASE.

Referenced by runCallbacksForSubnetID().

◆ hasCallbacks()

bool isc::dhcp::TrackingLeaseMgr::hasCallbacks ( ) const

Checks if any callbacks have been registered.

It is a quick check to be performed by the backends whether or not the callbacks mechanism is used.

Returns: true if any callbacks have been registered.

Definition at line 109 of file tracking_lease_mgr.cc.

References callbacks_.

◆ isLocked()

bool isc::dhcp::TrackingLeaseMgr::isLocked ( const LeasePtr & lease )

Checks if the lease is locked.

This function is useful in the unit tests.

Returns: true if the lease is locked, false otherwise.

Definition at line 40 of file tracking_lease_mgr.cc.

References locked_leases_.

◆ registerCallback() [1/2]

void isc::dhcp::TrackingLeaseMgr::registerCallback	(	TrackingLeaseMgr::CallbackType	type,
		std::string	owner,
		Lease::Type	lease_type,
		TrackingLeaseMgr::CallbackFn	callback_fn )

Registers a callback function for all subnets.

Parameters

type	callback type.
owner	callback owner identifier.
lease_type	a lease type.
callback_fn	callback function instance.

Exceptions

InvalidOperation when the callback has been already registered for the given owner and all subnets.

Definition at line 85 of file tracking_lease_mgr.cc.

References registerCallback().

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◆ registerCallback() [2/2]

void isc::dhcp::TrackingLeaseMgr::registerCallback	(	TrackingLeaseMgr::CallbackType	type,
		std::string	owner,
		SubnetID	subnet_id,
		Lease::Type	lease_type,
		TrackingLeaseMgr::CallbackFn	callback_fn )

Registers a callback function for a subnet.

Parameters

type	callback type.
owner	callback owner identifier.
subnet_id	subnet identifier; it can be set to 0 if the callback should be called for all subnets.
lease_type	a lease type.
callback_fn	callback function instance.

Exceptions

InvalidOperation when the callback has been already registered for the given owner and the subnet identifier.

Definition at line 60 of file tracking_lease_mgr.cc.

References callbacks_, isc_throw, and isc::dhcp::Lease::typeToText().

Referenced by registerCallback().

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◆ runCallbacks()

void isc::dhcp::TrackingLeaseMgr::runCallbacks	(	TrackingLeaseMgr::CallbackType	type,
		const LeasePtr &	lease )

protected

Runs registered callbacks of the particular type.

The specified lease instance contains the subnet identifier used to filter the callbacks to be invoked.

Parameters

type	callback type.
lease	lease instance for which the callbacks are invoked.

Definition at line 128 of file tracking_lease_mgr.cc.

References runCallbacksForSubnetID().

Referenced by trackAddLease(), trackDeleteLease(), and trackUpdateLease().

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◆ runCallbacksForSubnetID()

void isc::dhcp::TrackingLeaseMgr::runCallbacksForSubnetID	(	CallbackType	type,
		SubnetID	subnet_id,
		const LeasePtr &	lease )

protected

Runs registered callbacks of the particular type for a subnet id.

It is called internally by the runCallbacks function.

Parameters

type	callback type.
subnet_id	subnet identifier for which the callbacks are invoked.
lease	lease instance for which the callbacks are invoked.

Definition at line 135 of file tracking_lease_mgr.cc.

References callbacks_, callbackTypeToString(), isc::dhcp::DHCPSRV_LEASE_MGR_CALLBACK_EXCEPTION, isc::dhcp::DHCPSRV_LEASE_MGR_CALLBACK_UNKNOWN_EXCEPTION, isc::dhcp::dhcpsrv_logger, and LOG_WARN.

Referenced by runCallbacks().

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◆ trackAddLease()

void isc::dhcp::TrackingLeaseMgr::trackAddLease ( const LeasePtr & lease )

protected

Invokes the callbacks when a new lease is added.

It executes all callbacks of the TRACK_ADD_LEASE type for a subnet id of 0 and the subnet id associated with the lease.

The callbacks execution order is not guaranteed.

Parameters

lease new lease instance.

Definition at line 45 of file tracking_lease_mgr.cc.

References runCallbacks(), and TRACK_ADD_LEASE.

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◆ trackDeleteLease()

void isc::dhcp::TrackingLeaseMgr::trackDeleteLease ( const LeasePtr & lease )

protected

Invokes the callbacks when a lease is deleted.

It executes all callbacks of the TRACK_DELETE_LEASE type for a subnet id of 0 and the subnet id associated with the lease.

The callbacks execution order is not guaranteed.

Parameters

lease deleted lease instance.

Definition at line 55 of file tracking_lease_mgr.cc.

References runCallbacks(), and TRACK_DELETE_LEASE.

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◆ trackUpdateLease()

void isc::dhcp::TrackingLeaseMgr::trackUpdateLease ( const LeasePtr & lease )

protected

Invokes the callbacks when a lease is updated.

It executes all callbacks of the TRACK_UPDATE_LEASE type for a subnet id of 0 and the subnet id associated with the lease.

The callbacks execution order is not guaranteed.

Parameters

lease updated lease instance.

Definition at line 50 of file tracking_lease_mgr.cc.

References runCallbacks(), and TRACK_UPDATE_LEASE.

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◆ tryLock()

bool isc::dhcp::TrackingLeaseMgr::tryLock ( const LeasePtr & lease )

protected

Attempts to lock a lease.

If a lease is successfully locked, no other thread can lock it. It protects against running the callbacks out of order when two threads modify the same lease. Such a locking should only be used when the lease allocation followed by the callbacks invocation are not protected by some other synchronization mechanism. In particular, the Memfile backend uses a mutex for locking in the lease allocation functions. In this case, it is unnecessary to apply a lock at the lease level. The SQL backends rely on the database locking mechanisms to prevent the concurrent updates of the same lease. These backends must use the lease locking to ensure the correct callbacks invocation order.

This function is not thread-safe and must be invoked in a thread-safe context.

Parameters

lease a lease instance for which the lock should be attempted.

Returns: true when locking was successful, false otherwise. In the latter case, the thread should stop a lease allocation or deallocation attempt.

Definition at line 27 of file tracking_lease_mgr.cc.

References locked_leases_.

◆ unlock()

void isc::dhcp::TrackingLeaseMgr::unlock ( const LeasePtr & lease )

protected

Attempts to unlock a lease.

This function is not thread-safe and must be invoked in a thread-safe context.

Parameters

lease a lease instance for which unlocking should be attempted.

Definition at line 34 of file tracking_lease_mgr.cc.

References locked_leases_.

◆ unregisterAllCallbacks()

void isc::dhcp::TrackingLeaseMgr::unregisterAllCallbacks ( )

Unregisters all callbacks.

Definition at line 104 of file tracking_lease_mgr.cc.

References callbacks_.

◆ unregisterCallbacks()

void isc::dhcp::TrackingLeaseMgr::unregisterCallbacks	(	SubnetID	subnet_id,
		Lease::Type	lease_type )

Unregisters all callbacks for a given subnet identifier.

Parameters

subnet_id	a subnet identifier.
lease_type	a lease type.

Definition at line 93 of file tracking_lease_mgr.cc.

References callbacks_.

Friends And Related Symbol Documentation

◆ LeaseMgrFactory

friend class LeaseMgrFactory

friend

The LeaseMgrFactory manages the LeaseMgr instances and has to be able to move installed callbacks between them.

No other external class can have access to the callbacks container. Thus, we can't make the container public. The friend declaration deals with it cleanly.

Definition at line 83 of file tracking_lease_mgr.h.

Member Data Documentation

◆ callbacks_

CallbackContainerPtr isc::dhcp::TrackingLeaseMgr::callbacks_

protected

The multi-index container holding registered callbacks.

Definition at line 296 of file tracking_lease_mgr.h.

Referenced by hasCallbacks(), registerCallback(), runCallbacksForSubnetID(), unregisterAllCallbacks(), and unregisterCallbacks().

◆ locked_leases_

std::unordered_set<asiolink::IOAddress, asiolink::IOAddress::Hash> isc::dhcp::TrackingLeaseMgr::locked_leases_

protected

A set of locked leases.

It is empty if locking is not used (e.g. Memfile backend) or when there are no ongoing allocations.

Definition at line 302 of file tracking_lease_mgr.h.

Referenced by isLocked(), tryLock(), and unlock().

The documentation for this class was generated from the following files:

Classes

Public Types

Public Member Functions

Protected Types

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ CallbackContainer

◆ CallbackContainerPtr

◆ CallbackFn

Member Enumeration Documentation

◆ CallbackType

Constructor & Destructor Documentation

◆ TrackingLeaseMgr()

Member Function Documentation

◆ callbackTypeToString()

◆ hasCallbacks()

◆ isLocked()

◆ registerCallback() [1/2]

◆ registerCallback() [2/2]

◆ runCallbacks()

◆ runCallbacksForSubnetID()

◆ trackAddLease()

◆ trackDeleteLease()

◆ trackUpdateLease()

◆ tryLock()

◆ unlock()

◆ unregisterAllCallbacks()

◆ unregisterCallbacks()

Friends And Related Symbol Documentation

◆ LeaseMgrFactory

Member Data Documentation

◆ callbacks_

◆ locked_leases_