This bit me because I accidentally made the destructor for a class which
was wrapped in an Optional private. This causes none of the Optional
destructors to be able to be deduced, which when combined with concepts
causes an internal compile error in GCC 10.3.0+. This commit adds a note
here to make sure that future encounters of this bug does not surprise
people.
c27abaabc4 moved this out of the global
namespace, but did not qualify its users.
While this seems to be fine (sometimes, somehow), let's qualify it to
avoid random breakage.
This is in preparation for making KBufferBuilder::append() and friends
return a KResult. Long-term we should come up with a solution that works
for both kernel and userspace clients of the JSON API.
This type is useful, as the sizes will be visible in the compiler error
messages, as they will be part of the template parameters. This is not
possible with a normal static_assert of the sizeof a type.
The way we use classes like Kernel::KResultOr<T> and AK::Result<T, E>
makes checking for errors (and short-circuiting returns) quite verbose.
This patch adds a new TRY(expression) macro that either evaluates to
the released result of the expression if successful, or returns the
error if not.
Before:
auto foo_or_error = get_foo();
if (foo_or_error.is_error())
return foo_or_error.release_error();
auto foo = foo_or_error.release_value();
After:
auto foo = TRY(get_foo());
The macro uses a GNU C++ extension which is supported by GCC, Clang,
Intel C++, and possibly others. It's not *ideal*, but since it makes our
codebase considerably nicer, let's try(!) it out. :^)
Co-authored-by: Ali Mohammad Pur <mpfard@serenityos.org>
This commit moves the KResult and KResultOr objects to Kernel/API to
signify that they may now be freely used by userspace code at points
where a syscall-related error result is to be expected. It also exposes
KResult and KResultOr to the global namespace to make it nicer to use
for userspace code.
This function ensures that a key is present in the HashMap.
If it's not present, it is inserted, and the corresponding value
is initialized with whatever the callback returns.
It allows us to express this:
auto it = map.find(key);
if (it == map.end()) {
map.set(it, make_a_value());
it = map.find(key);
}
auto& value = it->value;
Like this:
auto& value = map.ensure(key, [] { return make_a_value(); });
Note that the callback is only invoked if we have to insert a missing
key into the HashMap. This is important in case constructing the default
value is expensive or otherwise undesirable.
This introduces a new define AK_DONT_REPLACE_STD that disables our own
implementation of std::move and std::forward. Some ports include both
STL and AK headers which causes conflicts when trying to resolve those
functions. The port can define AK_DONT_REPLACE_STD before including
Serenity headers in that case.
This avoids a value copy when calling value() or value_or() on a
temporary Optional. This is very common when using the HashMap::get()
API like this:
auto value = hash_map.get(key).value_or(fallback_value);
Our existing implementation did not check the element type of the other
pointer in the constructors and move assignment operators. This meant
that some operations that would require explicit casting on raw pointers
were done implicitly, such as:
- downcasting a base class to a derived class (e.g. `Kernel::Inode` =>
`Kernel::ProcFSDirectoryInode` in Kernel/ProcFS.cpp),
- casting to an unrelated type (e.g. `Promise<bool>` => `Promise<Empty>`
in LibIMAP/Client.cpp)
This, of course, allows gross violations of the type system, and makes
the need to type-check less obvious before downcasting. Luckily, while
adding the `static_ptr_cast`s, only two truly incorrect usages were
found; in the other instances, our casts just needed to be made
explicit.
And also try_create<T> => try_make_ref_counted<T>.
A global "create" was a bit much. The new name matches make<T> better,
which we've used for making single-owner objects since forever.
When swapping the same object, we could end up with a double-free error.
This was found while quick-sorting a Vector of Variants holding complex
types, reproduced by the new swap_same_complex_object test case.
Static analysis correctly flags that we are missing an implementation
for `operator delete` for all classes which are annotated with
AK_MAKE_ETERNAL. To appease static analysis define an implementation
which asserts to make sure no one ever calls delete on the object.
The assumption that FlatPtr is 64-bit on every platform except i686 is
not correct, and also makes the definition of explode_byte() less nice
to look at.
The IRC Client application made some sense while our main communication
hub was an IRC channel. Now that we've moved on, IRC is just a random
protocol with no particular relevance to this project.
This also has the benefit of removing one major client of the single-
process Web::InProcessWebView class.
This parsing is already duplicated between LibJS and LibRegex, and will
shortly be needed in more places in those libraries. Move it to AK to
prevent further duplication.
This API will consume escaped Unicode code points of the form:
\\u{code point}
\\unnnn (where each n is a hexadecimal digit)
\\unnnn\\unnnn (where the two escaped values are a surrogate pair)
This is primarily to be able to remove the GenericLexer include out of
Format.h as well. A subsequent commit will add AK::Result to
GenericLexer, which will cause naming conflicts with other structures
named Result. This can be avoided (for now) by preventing nearly every
file in the system from implicitly including GenericLexer.
Other changes in this commit are to add the GenericLexer include to
files where it is missing.
If a member is an empty class, the standard normally stats that it needs
to have a size of at least 1 byte in order to guarantee that the
addresses of distinct objects of the same type are always distinct.
However as of c++20, we can use [[no_unique_address]] to instruct the
compiler that if the member has an empty type, it may optimize it to
occupy no space.
This typo / bug in the Traits<T> implementation for StringView caused
AK::HashMap methods to return a `String` when looking up values out of
a hash map of type HashTable<StringView,StringView>.
This change fixes the typo, and fixes the only consumer, the kernel
Commandline class.
This is basically a complement to adopt_nonnull_ref_or_enomem, and
simplifies boilerplate for try_create functions which just return ENOMEM
or the object based on whether it was able to allocate.
Problem:
- `AK::Detail::integer_sequence_generate_array` is published via a
`using` directive in the `Array.h` header, but this is a `Detail`
function.
Solution:
- Remove the `using` declaration.
In the quest of removing as timespec / timeval usage in the Userland as
possible, we need a way to conveniently retrieving the current clock
time from the kernel and storing it in `AK::Time` format.
