The handling of filesystem level errors was basically non-existing or
consisting of `VERIFY_NOT_REACHED` assertions. Addressed this by
* Adding `open` methods to `Heap` and `Database` which return errors.
* Changing the interface of methods of these classes and clients
downstream to propagate these errors.
The constructors of `Heap` and `Database` don't open the underlying
filesystem file anymore.
The SQL statement handlers return an `SQLErrorCode::InternalError`
error code if an error comes back from the lower levels. Note that some
of these errors are things like duplicate index entry errors that should
be caught before the SQL layer attempts to actually update the database.
Added tests to catch attempts to open weird or non-existent files as
databases.
Finally, in between me writing this patch and submitting the PR the
AK::Result<Foo, Bar> template got deprecated in favour of ErrorOr<Foo>.
This resulted in more busywork.
The database the sql client connected to was 'hardcoded' to the login
name of the calling user.
- Extended the IPC API to be more expressive when connecting, by
returning the name of the database the client connected to in the
'connected' callback.
- Gave the sql client a command line argument (-d/--database) allowing
an alternative database name to be specified
A subsequent commit will have a dot command allowing the user to
connect to different databases from the same sql session.
If you capture a stack variable by reference in a lamdba definition,
and this lambda outlives the scope of the stack variable, this reference
may point to garbage when the lambda is executed. Therefore capture as
little as possible (typically only ``this``), and what is captured is
captured by value
Only one place used this argument and it was to hold on to a strong ref
for the object. Since we already do that now, there's no need to keep
this argument around since this can be easily captured.
This commit contains no changes.
In the DatabaseConnection constructor, there's a deferred_invoke
callback that references the client_id. But depending on when the
callback occurs, the reference of the client_id can change. This created
a problem when connecting to SQLServer using the SQL utility because
depending on when the callback was invoked, the client_id could change.
m_client_id is set in the constructor and that reference will not change
depending on when the callback is invoked.
This patch introduces the SQLServer system server. This service is
supposed to be the only process/application talking to database storage.
This makes things like locking and caching more reliable, easier to
implement, and more efficient.
In LibSQL we added a client component that does the ugly IPC nitty-
gritty for you. All that's needed is setting a number of event handler
lambdas and you can connect to databases and execute statements on them.
Applications that wish to use this SQLClient class obviously need to
link LibSQL and LibIPC.
