#include <flint_lock.h>

Collaboration diagram for FlintLock:

Public Types
enum	reason { SUCCESS, INUSE, UNSUPPORTED, FDLIMIT, UNKNOWN }

Public Member Functions
	FlintLock (const std::string &filename_)
	Standard constructor. More...

	FlintLock ()
	Constructor for use in read-only cases (like single-file glass). More...

	operator bool () const

	~FlintLock ()

bool	test () const
	Test if the lock is held. More...

reason	lock (bool exclusive, bool wait, std::string &explanation)
	Attempt to obtain the lock. More...

void	release ()
	Release the lock. More...

void	throw_databaselockerror (FlintLock::reason why, const std::string &db_dir, const std::string &explanation) const
	Throw Xapian::DatabaseLockError. More...

Private Attributes
std::string	filename

int	fd = -1

pid_t	pid

Detailed Description

Definition at line 39 of file flint_lock.h.

Member Enumeration Documentation

◆ reason

enum FlintLock::reason

Enumerator
SUCCESS
INUSE
UNSUPPORTED
FDLIMIT
UNKNOWN

Definition at line 51 of file flint_lock.h.

Constructor & Destructor Documentation

◆ FlintLock() [1/2]

FlintLock::FlintLock ( const std::string & filename_ )

inlineexplicit

Standard constructor.

Definition at line 60 of file flint_lock.h.

◆ FlintLock() [2/2]

FlintLock::FlintLock ( )

inline

Constructor for use in read-only cases (like single-file glass).

Definition at line 69 of file flint_lock.h.

◆ ~FlintLock()

FlintLock::~FlintLock ( )

inline

Definition at line 80 of file flint_lock.h.

References lock(), release(), test(), and throw_databaselockerror().

Member Function Documentation

◆ lock()

FlintLock::reason FlintLock::lock	(	bool	exclusive,
		bool	wait,
		std::string &	explanation
	)

Attempt to obtain the lock.

If the attempt fails with code "UNKNOWN", the string supplied in the explanation parameter will be set to contain any details available of the reason for the failure.

Parameters

exclusive	Get an exclusive lock? Value currently ignored, and the lock is always exclusive.
wait	Wait until we can get the lock?

Definition at line 125 of file flint_lock.cc.

References Assert, close(), Xapian::Internal::closefrom(), errno_to_string(), O_CLOEXEC, Xapian::InMemory::open(), rare, SOCK_CLOEXEC, and usual.

Referenced by ChertDatabaseReplicator::apply_changeset_from_conn(), GlassDatabaseReplicator::apply_changeset_from_conn(), GlassDatabase::compact(), ChertDatabase::compact(), GlassDatabase::get_database_write_lock(), ChertDatabase::get_database_write_lock(), and ~FlintLock().

◆ operator bool()

FlintLock::operator bool ( ) const

inline

Definition at line 71 of file flint_lock.h.

◆ release()

void FlintLock::release ( )

Release the lock.

Definition at line 459 of file flint_lock.cc.

References close().

Referenced by GlassDatabase::close(), ChertDatabase::close(), GlassDatabase::compact(), and ~FlintLock().

◆ test()

bool FlintLock::test ( ) const

Test if the lock is held.

If this object holds the lock, just returns true. Otherwise it will try to test taking the lock, if that is possible to do on the current platform without actually take it (fcntl() locks support this).

Throws Xapian::UnimplemenetedError if the platform doesn't support testing the lock in this way, or Xapian::DatabaseLockError if there's an error while trying to perform the test.

Definition at line 75 of file flint_lock.cc.

References close(), O_CLOEXEC, Xapian::InMemory::open(), and throw_cannot_test_lock().

Referenced by GlassDatabase::locked(), ChertDatabase::locked(), and ~FlintLock().