This patch allows to insert "%uid" in `IPC_CLIENT_CONNECTION`
declaration and in SystemServer's ini files. This pattern is replaced
then replaced by the UID of the owner of the service. It opens a path
for seamlessly managed, per-user portal.
This prevents us from needing a sv suffix, and potentially reduces the
need to run generic code for a single character (as contains,
starts_with, ends_with etc. for a char will be just a length and
equality check).
No functional changes.
Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).
No functional changes.
Error::from_string_literal now takes direct char const*s, while
Error::from_string_view does what Error::from_string_literal used to do:
taking StringViews. This change will remove the need to insert `sv`
after error strings when returning string literal errors once
StringView(char const*) is removed.
No functional changes.
`static const` variables can be computed and initialized at run-time
during initialization or the first time a function is called. Change
them to `static constexpr` to ensure they are computed at
compile-time.
This allows some removal of `strlen` because the length of the
`StringView` can be used which is pre-computed at compile-time.
Now that expression evaluation can use TRY, we can allow binary operator
methods to fail as well. This also fixes a few instances of converting a
Value to a double when we meant to convert to an integer.
If a tuple has a single value, perform a comparison using that singular
value. This allows, for example, comparisons of the form "(1) < 4",
where (1) is a single element tuple.
Instead of setting an error in the execution context, we can directly
return that error or the successful value. This lets all callers, who
were already TRY-capable, simply TRY the expression evaluation.
The result of a SQL statement execution is either:
1. An error.
2. The list of rows inserted, deleted, selected, etc.
(2) is currently represented by a combination of the Result class and
the ResultSet list it holds. This worked okay, but issues start to
arise when trying to use Result in non-statement contexts (for example,
when introducing Result to SQL expression execution).
What we really need is for Result to be a thin wrapper that represents
both (1) and (2), and to not have any explicit members like a ResultSet.
So this commit removes ResultSet from Result, and introduces ResultOr,
which is just an alias for AK::ErrorOrr. Statement execution now returns
ResultOr<ResultSet> instead of Result. This further opens the door for
expression execution to return ResultOr<Value> in the future.
Lastly, this moves some other context held by Result over to ResultSet.
This includes the row count (which is really just the size of ResultSet)
and the command for which the result is for.
The existing SQLResult class predates our TRY semantics. As a result, in
the AST execution methods, there is a lot of is_error checking on values
that could instead be wrapped with TRY. This new class will allow such
semantics, and is also stack allocated (no need to be a RefPtr). It is
heavily based on LibJS's completion class.
This statement (for now) outputs the name and types of the different
attributes in a table. It's not standard SQL but all DBMSs that I know
of implement a sort of statement for such functionality.
Since the output of DESCRIBE TABLE is just a relation, an internal
schema, `master` was created and a table definition for DESCRIBE into
it. The table definition and the master schema are not accessible by the
user.
Apologies for the enormous commit, but I don't see a way to split this
up nicely. In the vast majority of cases it's a simple change. A few
extra places can use TRY instead of manual error checking though. :^)
The implementation of LIKE uses regexes under the hood, and this
implementation of REGEXP takes the same approach. It employs
PosixExtended from LibRegex with case insensitive and Unicode flags
set. The implementation of LIKE is based on SQLlite specs, but SQLlite
does not offer directions for a built-in regex functionality, so this
one uses LibRegex.
Ordering is done by replacing the straight Vector holding the query
result in the SQLResult object with a dedicated Vector subclass that
inserts result rows according to their sort key using a binary search.
This is done in the ResultSet class.
There are limitations:
- "SELECT ... ORDER BY 1" (or 2 or 3 etc) is supposed to sort by the
n-th result column. This doesn't work yet
- "SELECT ... column-expression alias ... ORDER BY alias" is supposed to
sort by the column with the given alias. This doesn't work yet
What does work however is something like
```SELECT foo FROM bar SORT BY quux```
i.e. sorted by a column not in the result set. Once functions are
supported it should be possible to sort by random functions.
This change unfortunately cannot be atomically made without a single
commit changing everything.
Most of the important changes are in LibIPC/Connection.cpp,
LibIPC/ServerConnection.cpp and LibCore/LocalServer.cpp.
The notable changes are:
- IPCCompiler now generates the decode and decode_message functions such
that they take a Core::Stream::LocalSocket instead of the socket fd.
- IPC::Decoder now uses the receive_fd method of LocalSocket instead of
doing system calls directly on the fd.
- IPC::ConnectionBase and related classes now use the Stream API
functions.
- IPC::ServerConnection no longer constructs the socket itself; instead,
a convenience macro, IPC_CLIENT_CONNECTION, is used in place of
C_OBJECT and will generate a static try_create factory function for
the ServerConnection subclass. The subclass is now responsible for
passing the socket constructed in this function to its
ServerConnection base; the socket is passed as the first argument to
the constructor (as a NonnullOwnPtr<Core::Stream::LocalServer>) before
any other arguments.
- The functionality regarding taking over sockets from SystemServer has
been moved to LibIPC/SystemServerTakeover.cpp. The Core::LocalSocket
implementation of this functionality hasn't been deleted due to my
intention of removing this class in the near future and to reduce
noise on this (already quite noisy) PR.
The evaluation order of method parameters is unspecified in C++, and
so we couldn't rely on parse_statement() being called before
parse_escape() when building a MatchExpression.
With this patch, we explicitly parse what we need in the right order,
before building the MatchExpression object.
This option is already enabled when building Lagom, so let's enable it
for the main build too. We will no longer be surprised by Lagom Clang
CI builds failing while everything compiles locally.
Furthermore, the stronger `-Wsuggest-override` warning is enabled in
this commit, which enforces the use of the `override` keyword in all
classes, not just those which already have some methods marked as
`override`. This works with both GCC and Clang.
Fixes a crash that was caused by a syntax error which is difficult to
catch by the parser: usually identifiers are accepted in column lists,
but they are not in a list of column values to be inserted in an INSERT.
Fixed this by putting in a heuristic check; we probably need a better
way to do this.
Included tests for this case.
Also introduced a new SQL Error code, `NotYetImplemented`, and return
that instead of crashing when encountering unimplemented SQL.
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.
Same as Vector, ByteBuffer now also signals allocation failure by
returning an ENOMEM Error instead of a bool, allowing us to use the
TRY() and MUST() patterns.
This patch introduces table joins. It uses a pretty dumb algorithm-
starting with a singleton '__unity__' row consisting of a single boolean
value, a cartesian product of all tables in the 'FROM' clause is built.
This cartesian product is then filtered through the 'WHERE' clause,
again without any smarts just using brute force.
This patch required a bunch of busy work to allow for example the
ColumnNameExpression having to deal with multiple tables potentially
having columns with the same name.
Because SQL is the craptastic language that it is, sometimes expressions
need to know details about the calling statement. For example the tables
in the 'FROM' clause may be needed to determine which columns are
referenced in 'WHERE' expressions. So the current statement is added
to the ExecutionContext and a new 'execute' overload on Statement is
created which takes the Database and the Statement and builds an
ExecutionContaxt from those.
These are needed to distinguish columns from different tables with the
same column name in one and the same (joined) Tuple. Not quite happy
yet with this API; I think some sort of hierarchical structure would be
better but we'll burn that bridge when we get there :^)
Derivatives of Core::Object should be constructed through
ClassName::construct(), to avoid handling ref-counted objects with
refcount zero. Fixing the visibility means that misuses like this are
more difficult.
