We don't do anything particular with images that contain a custom
ColourEncoding yet, but at least it allows us to know how to decode the
metadata of such images.
Complex distribution - distributions that are encoded using an internal
symbol decoder with a single distribution, are very often used for lz77
compressed images. This is a requirement for the lz77_flower test case.
This type of cluster is an exception and has specific rules (but
simpler) to be read. This is a requirement to support complex
distributions as they use a symbol decoder initialized with a single
distribution.
Otherwise, if an application defines its own macros, the implementations
get messed up. This way we redefine those macros if they're set.
This fixes the PHP port build.
tl;dr: This fixes deadlocks that would occur in most applications in
Serenity when SMP was enabled.
As an optimization to `pthread_mutex_unlock()`, if only one thread
holds a mutex lock, it will avoid calling `futex()` to wake, since no
threads are actually waiting in `futex()`.
If a thread manages to synchronously unlock and relock the same mutex,
the state will be set to indicate that a wake is not needed, regardless
of whether any other threads are waiting for the lock. This should be
fine, as a thread that is waiting will set the mutex to needing a wake
and check if it is unlocked to unblock itself in the same atomic
operation.
However, when `pthread_mutex_lock()` was called with only one thread
holding the mutex lock, instead of telling `futex()` to atomically
sleep the thread if the state is set to indicate that a wake is
needed, the first wait would check if the state was set to indicate a
wake was _not_ needed. This means it is possible for the call to
`futex()` to wait when any subsequent call to `pthread_mutex_unlock()`
would not call `futex()` to wake, causing it to wait forever.
After that, any other thread that tries to take the lock will see that
the lock is taken and also `futex()` wait. Despite the fact that these
other threads would set the state to needing a wake, there will be no
unblocked thread holding the lock to actually wake them.
By making it wait only if the state indicates to other threads that a
wake is needed, heavily contended mutexes should no longer cause
deadlocks. Most applications would encounter these deadlocks due to the
mutex used by `malloc()`, some sooner than others. The worst offenders
(other than Ladybird) were most likely VideoPlayer and SoundPlayer.
For now, we parse these, but don't actually consider the namespace when
matching them. `DOM::Element` does not (yet) store attribute namespaces
so we can't check what they are.
Holding the `prefix` as a StringView meant it pointed at string data
held by `token`. `token` gets reassigned shortly afterwards, meaning
`prefix` would hold invalid character data.
This is basically a name with a namespace prefix. It will be used for
adding namespaces to Universal, TagName, and Attribute selectors.
For convenience, this can also optionally parse/store the `*` wildcard
character as the name.
This allows us to read many more images. This decoder is one of the two
possibilities (along Brotli) that can be used for modular images. All
the logic is directly taken from the spec.
One of the image that can now be decoded is "Lucifer's Dominion:
Synthesis" that can be found on `https://jpegxl.info/art/`, it also
makes us pass one more test of the conformance test suite, namely
"alpha_triangles".
JPEG XL supports two types of entropy encoding: the first one is
Huffman-based (Brotli) and the second one is based on ANS. To introduce
the latter, we start by storing the `Vector` of distributions in a
`Variant`. This will allow us to choose which entropy decoder we use
during execution.
is_scroll_container() returns true for "overflow: hidden" which allows
programmable scrolling while is_scrollable() returns true only for
"overflow: scroll" and "overflow: auto" which allow scrolling only by
user interactions.
Fixes painting of nested nodes in scrollable containers by moving
painter's scroll offset translation from paint_node() to
before_children_paint() and after_children_paint().
WavWriter and the shot utility open files with this mode and never
truncate the files, which might leave some contents of a previous file
during overwriting.
This makes it easy to set up a realm, global object and root execution
context with a single call to LibJS. It will be useful to basically
everyone except LibWeb.
Build a grid snapped to device pixels and use it to construct the
rectangles for the cell edges, same as for collapsed borders. This is
especially important when border-spacing is set to 0 since it avoids
gaps between adjacent cells which have borders set.
- Out-of-flow items should not affect grid layout
- "The static position of an absolutely-positioned child of a grid
container is determined as if it were the sole grid item in a grid
area whose edges coincide with the content edges of the grid
container."
When determining the precedence of the + and - operators, the parser
always returned the precedence using these operators in a binary
expression (lower than division!). The context of whether the operator
is used in a unary or binary expression must be taken into account.
This invariant is enforced by the fact that `NonnullGCPtr` can only be
constructed from references.
This commit fixes an instance where we compared a pointer to null after
we have already dereferenced it.
The compiler-generated copy constructor and copy assignment operator
already do the right thing (which is to simply copy the underlying
pointer).
The [Itanium C++ ABI][1] treats any class with non-trivial copy/move
constructors and destructors as non-trivial for the purposes of calls --
even if they are functionally identical to the compiler-generated ones.
If a class is non-trivial, it cannot be passed or returned in registers,
only via an invisible reference, which is worse for codegen. This commit
makes `{Nonnull,}GCPtr` trivial.
As the compiler can be sure that capturing a `GCPtr` by value has no
side effects, a few `-Wunused-lambda-capture` warnings had to be
addressed in LibWeb.
GCC seems to have a bug that prevents `ExceptionOr<Variant<GCPtr<T>>>`
from being implicitly constructed from `GCPtr<T>` after this change. A
non-invasive workaround is to explicitly construct the inner Variant
type.
[1]: https://itanium-cxx-abi.github.io/cxx-abi/abi.html#non-trivial
This method will be used by the package manager code to render an actual
Port's name to raw text as it is stored as relative URL currently in the
AvailablePorts.md file.
Previously, case-change operations did not produce visible results.
As of now, setting `m_chars_touched_in_the_middle` to a non-zero value
results in refreshing the whole line. So case-change operations now set
that variable (causing a line refresh) in order to produce visible
results as expected.
This method can be used to force the current process to sleep, waiting
for a debugger to attach. On attach, the debugger breaks at the callsite
directly.
This is tested on Linux and macOS, in Clion and also terminal gdb and
lldb.
The user can now save, load, and view calendars. A calendar is made up
of an array of events which are saved in a JSON file. In the future we
should implement the iCalendar standard instead of using a custom
format.
