For every IPC message sent, we currently prepend the message size to the
IPC message buffer. This incurs the cost of copying the entire message
to its newly allocated position. Instead, reserve the bytes for the size
at the front of the buffer upon creation. Prevent dangerous access to
the buffer with specific public methods.
This large block of code is repeated nearly verbatim in LibWeb. Move it
to a helper function that both LibIPC and LibWeb can defer to. This will
let us make changes to this method in a singular location going forward.
Note this is a bit of a regression for the MessagePort. It now suffers
from the same performance issue that IPC messages face - we prepend the
meessage size to the message buffer. This degredation is very temporary
though, as a fix is imminent, and this change makes that fix easier.
The type of MessageBuffer will be changing, and it was a bit awkward to
look around to find where the forward declaration was. This patch just
moves it to the obvious forwarding header.
We cannot port over Optional<FlyString> until the IDL generator supports
passing that through as an argument (as opposed to an Optional<String>).
Change to FlyString where possible, and resolve any fallout as a result.
Other readers do this too, and files depend on this.
Fixes opening these four files from the PDFA 0000.zip dataset:
* 0000015.pdf
Starts with `C:\web\webeuncet\_cat\_docs\_publics\` before header
* 0000408.pdf
Starts with UTF-8 BOM
* 0000524.pdf
Starts with 867 bytes of HTML containing a PHP backtrace
* 0000680.pdf
Starts with `C:\web\webeuncet\_cat\_docs\_publics\` too
A local (non-public) PDF I have lying around contains this in
a page's operator stream:
```
[<00b4003e> 3 <002600480051> 3 <005700550044004f0003> -29
<00330044> 3 <0055> -3 <004e0040> 4 <0003> -29 <004c00560003> -31
<0057004b> 4 <00480003> -37 <0050
>] TJ
```
That is, there's a newline in a hexstring after a character.
This led to `Parser error at offset 5184: Unexpected character`.
The spec says in 3.2.3 String Objects, Hexadecimal Strings:
"""Each pair of hexadecimal digits defines one byte of the string.
White-space characters (such as space, tab, carriage return, line feed,
and form feed) are ignored."""
But we didn't ignore whitespace before or after a character, only
in between the bytes.
The spec also says:
"""If the final digit of a hexadecimal string is missing—that is, if
there is an odd number of digits—the final digit is assumed to be 0."""
In that case, we were skipping the closing `>` twice -- or, more
accurately, we ignored the character after it too. This has been
wrong all the way back in #6974.
Add a test that fails if either of the two changes isn't present.
Instead of implementing stacking context painting order exactly as it
is defined in CSS2.2 "Appendix E. Elaborate description of Stacking
Contexts" we need to account for changes in the latest standards where
a box can establish a stacking context without being positioned, for
example, by having an opacity different from 1.
Fixes https://github.com/SerenityOS/serenity/issues/21137
This change fixes the initial tool selection when pixelpaint is started
with a path. Previously an already existing editor was expected when
the default tool was initially propagated - which was not the case if
pixelpaint was launched to directly load an existing image.
The JS::Value being passed through is not a bigint, and needs to be
converted using ConvertToInt, as per:
https://webidl.spec.whatwg.org/#es-unsigned-long-long
Furthermore, the IDL definition also specifies that this is associated
with the [EnforceRange] extended attribute.
This makes it actually possible to pass through an autoAllocateChunkSize
to the ReadableStream constructor without it throwing a TypeError.
JS::modulo was yielding a result of '0' for the input:
```
modulo(1., 18446744073709551616.)
```
Instead of the expected '1'.
As far as I can tell the reason for this is that the repeated calls to
fmod is losing precision in the calculation, leading to the wrong
result. Fix this by only calling fmod once, and preserving the negative
value behaviour by an 'if' check.
Without this, the LibWeb text test:
`/Streams/ReadableByteStream-enqueue-respond.html`
Would hang forever after using this function in the IDL conversion of a
u64 in ConvertToInt.
This should also be more efficient :^)
These IPCs are different than other IPCs in that we can't just set up a
callback function to be invoked when WebContent sends us the screenshot
data. There are multiple places that would set that callback, and they
would step on each other's toes.
Instead, the screenshot APIs on ViewImplementation now return a Promise
which callers can interact with to receive the screenshot (or an error).
This overload is currently unused. When used, it doesn't compile due to
mismatched return types in the handler provided to the function and the
type of `on_resolution`.
Some servers decide to add newlines (and not \r\n) into that field, this
commit makes us tolerate that and not crash in cases like in #22463.
Fixes#22463.
Instead of returning HeapBlock memory to the kernel (or a non-type
specific shared cache), we now keep a BlockAllocator per CellAllocator
and implement "deallocation" by basically informing the kernel that we
don't need the physical memory right now.
This is done with MADV_FREE or MADV_DONTNEED if available, but for other
platforms (including SerenityOS) we munmap and then re-mmap the memory
to achieve the same effect. It's definitely clunky, so I've added a
FIXME about implementing the madvise options on SerenityOS too.
The important outcome of this change is that GC types that use a
type-specific allocator become immune to use-after-free type confusion
attacks, since their virtual addresses will only ever be re-used for
the same exact type again and again.
Fixes#22274
In XYZ space, gray doesn't have three equal values. Instead, it is
a line through the whitepoint.
(Multiplying by the whitepoint has the same effect as multiplying
the sRGB matrix with a (g, g, g) vector, since the numbers on
the matrix's rows add up to the whitepoint.)
Fixes the very slight red tint on all the figures in chapter 4
of the PDF 1.7 spec.
We were previously only checking the first value, this is wrong for tags
that accept multiple values (e.g. ExtraSamples) and can lead to crashes
on malformed images containing tags with a count of 0.
The TIFF spec is constructed in a way that many tags are defined in
multiple places but some of these definitions are partial. If we look
into "Section 8: Baseline Field Reference Guide", we can see that these
tags indeed have an enforced length of 1.
Using a vector to represent a list of painting commands results in many
reallocations, especially on pages with a lot of content.
This change addresses it by introducing a SegmentedVector, which allows
fast appending by representing a list as a sequence of fixed-size
vectors. Currently, this new data structure supports only the
operations used in RecordingPainter, which are appending and iterating.
