Defines an exception-safe wrapper around collection::transaction_t with unique ownership. More...

#include <ejdb.hpp>

Inheritance diagram for ejdb::unique_transaction:

Public Member Functions
	unique_transaction () noexcept=default
	Default constructor. Does not own a collection::transaction_t.

	unique_transaction (collection::transaction_t &trans)
	Constructs from a collection::transaction_t and starts transaction. More...

	unique_transaction (collection::transaction_t &trans, adopt_transaction_t) noexcept
	Constructs from a collection::transaction_t and adopts its status.

	unique_transaction (collection::transaction_t &trans, try_transaction_t) noexcept
	Constructs from a collection::transaction_t and attempts to start transaction.

	unique_transaction (unique_transaction &&) noexcept
	Move constructor. More...

void	abort ()
	Aborts all changes since starting a transaction. More...

void	commit ()
	Commits all changes since starting a transaction. More...

	operator bool () const noexcept
	Returns whether or not a collection::transaction_t is currently owned and has a transaction in progress.

unique_transaction &	operator= (unique_transaction &&)
	Move assignment. More...

bool	owns_transaction () const noexcept
	Returns whether or not a collection::transaction_t is currently owned and has a transaction in progress.

collection::transaction_t *	release () noexcept
	Releases ownership of current collection::transaction_t, if any, without terminating its transaction.

void	start ()
	Starts a transaction. More...

Detailed Description

Defines an exception-safe wrapper around collection::transaction_t with unique ownership.

Uses RAII to allow safe usage of a collection::transaction_t in the presence of exceptions. When a collection::transaction_t is owned, the destructor aborts transaction when an exception is thrown, otherwise commits.

The parent db object is guaranteed to remain alive throughout the lifetime of a unique_transaction.

The parent collection object must stay alive at least as long as a unique_transaction when it owns or contains a collection::transaction_t.

Constructor & Destructor Documentation

ejdb::unique_transaction::unique_transaction ( collection::transaction_t & trans )

explicit

Constructs from a collection::transaction_t and starts transaction.

Exceptions

std::system_error with an ejdb::errc when the transaction could not be started.

ejdb::unique_transaction::unique_transaction ( unique_transaction && other )

noexcept

Move constructor.

Parameters

other unique_transaction to construct from.

Ensures other neither owns nor is associated with a collection::transaction_t, avoiding erroneous transaction termination.

void ejdb::unique_transaction::abort ( )

Aborts all changes since starting a transaction.

Exceptions

std::system_error	with std::errc::operation_not_permitted when referenced collection::transaction_t is null.
std::system_error	with errc::illegal_transaction_state when the transaction has already been terminated.
std::system_error	with an ejdb::errc when the transaction could not be aborted.

void ejdb::unique_transaction::commit ( )

Commits all changes since starting a transaction.

Exceptions

std::system_error	with std::errc::operation_not_permitted when referenced collection::transaction_t is null.
std::system_error	with errc::illegal_transaction_state when the transaction has already been terminated.
std::system_error	with an ejdb::errc when the transaction could not be committed.

unique_transaction & ejdb::unique_transaction::operator= ( unique_transaction && other )

Move assignment.

Parameters

other unique_transaction to assign from.

Aborts current transaction if one is owned.

Ensures other neither owns nor is associated with a collection::transaction_t, avoiding erroneous transaction termination.

Exceptions

whatever abort() may throw.

void ejdb::unique_transaction::start ( )

Starts a transaction.

Exceptions

std::system_error	with std::errc::operation_not_permitted when referenced collection::transaction_t is null.
std::system_error	with errc::illegal_transaction_state when the transaction has already been started.
std::system_error	with an ejdb::errc when the transaction could not be started.

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