The MIME type can come from either the Content-Type header in the
response header list, or the overridden MIME type passed into
overrideMimeType()
This is required by Google Maps, which downloads blobs encoded
in x-user-defined format.
It's a pretty simple charset: the bottom 128 bytes (0x00-0x7F) are
standard ASCII, while the top 128 bytes (0x80-0xFF) are mapped to a
portion of the Unicode Private Use Area, specifically 0xF780-0xF7FF.
This is used by Google Maps for certain blobs.
This functions takes a user-provided decoder and will only use it if no
BOM is in the input.
If there is a BOM, it will ignore the given decoder and instead decode
the input with the appropriate Unicode decoder for the detected BOM.
This is only to be used where it's specifically needed, for example XHR
uses this for compatibility with deployed content. As such, it has an
obnoxious name to discourage usage.
This takes the input and sniffs it for a BOM. If it has the UTF-8 or
UTF-16BE BOM, it will return their respective decoder. Currently we
don't have a UTF-16LE decoder, so it will assert TODO if it detects
a UTF-16LE BOM. If there is no recognisable BOM, it will return no
decoder.
This allows you to ignore the Content-Type returned by the server and
always parse the content as if it's the given MIME type.
This will currently be used for allowing you to override the charset
of text responses.
According to RFC 6455 sections 5.5.2-5.5.3 Ping and Pong frames
can have empty "Application data" that means payload can be of size 0.
This change fixes failed "buffer.size()" assertion inside
of Core::Stream::write_or_error by not trying to send empty payload
in WebSocket::send_frame.
According to rfc2616 section 6.1 the text of reason phrase is not
defined and can be replaced by server.
Some servers (for example http://linux.org.ru) leave it empty.
This change fixes parsing of HTTP responses with empty reason phrase.
When entering the InBody state LibHTTP performs a
can_read_without_blocking check, which is duplicated immediately
afterwards. This initial call is removed.
When LibHTTP encountered the blank line between the headers and the body
in a HTTP response it made a call the m_socket->can_read_line(). This
ultimately tried to find a newline in the stream. If the response body
was small and did not contain a new line then the request would hang.
The call to m_socket->can_read_line() is removed so that the code is
able to progress into the body reading loop.
This is all still quite ad-hoc. Eventually these will both need to
support units (like with CSS Lengths) but for now we can continue only
using numbers.
I've chosen the name `AttributeParser` since it parses data from
attributes. Rather than duplicate the parsing of numbers and other
basic types, let's make use of this existing parsing code for parsing
the data for `<line>`, `<polyline>`, etc.
From the spec:
> Interface SVGGeometryElement represents SVG elements whose rendering
> is defined by geometry with an equivalent path, and which can be
> filled and stroked. This includes paths and the basic shapes.
- https://svgwg.org/svg2-draft/types.html#InterfaceSVGGeometryElement
Making them all create an SVGPathBox, and return a Path from get_path(),
means we can implement the "basic shapes" using the path system we
already have. :^)
Instead of using ByteBuffer::slice() to carve off the remaining part of
the payload every time we flush a part of it, we now keep a sliding
span (ReadonlyBytes) over it.
The DT_RELR relocation is a relatively new relocation encoding designed
to achieve space-efficient relative relocations in PIE programs.
The description of the format is available here:
https://groups.google.com/g/generic-abi/c/bX460iggiKg/m/Pi9aSwwABgAJ
It works by using a bitmap to store the offsets which need to be
relocated. Even entries are *address* entries: they contain an address
(relative to the base of the executable) which needs to be relocated.
Subsequent even entries are *bitmap* entries: "1" bits encode offsets
(in word size increments) relative to the last address entry which need
to be relocated.
This is in contrast to the REL/RELA format, where each entry takes up
2/3 machine words. Certain kinds of relocations store useful data in
that space (like the name of the referenced symbol), so not everything
can be encoded in this format. But as position-independent executables
and shared libraries tend to have a lot of relative relocations, a
specialized encoding for them absolutely makes sense.
The authors of the format suggest an overall 5-20% reduction in the file
size of various programs. Due to our extensive use of dynamic linking
and us not stripping debug info, relative relocations don't make up such
a large portion of the binary's size, so the measurements will tend to
skew to the lower side of the spectrum.
The following measurements were made with the x86-64 Clang toolchain:
- The kernel contains 290989 relocations. Enabling RELR decreased its
size from 30 MiB to 23 MiB.
- LibUnicodeData contains 190262 relocations, almost all of them
relative. Its file size changed from 17 MiB to 13 MiB.
- /bin/WebContent contains 1300 relocations, 66% of which are relative
relocations. With RELR, its size changed from 832 KiB to 812 KiB.
This change was inspired by the following blog post:
https://maskray.me/blog/2021-10-31-relative-relocations-and-relr
pledge_domains() that takes only one String argument was specifically
added as a shortcut for pledging a single domain. So, it makes sense to
use singular here.
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.
This wrapper is particularly helpful as we use a combination of similar
syscalls on Linux to simulate the behavior of the Serenity-exclusive
anon_create syscall. Users therefore won't have to worry about the
platform anymore :^)
This patch introduces the StyleComputer::RuleCache, which divides all of
our (author) CSS rules into buckets.
Currently, there are two buckets:
- Rules where a specific class must be present.
- All other rules.
This allows us to check a significantly smaller set of rules for each
element, since we can skip over any rule that requires a class attribute
not present on the element.
This takes the typical numer of rules tested per element on Discord from
~16000 to ~550. :^)
We can definitely improve the cache invalidation. It currently happens
too often due to media queries. And we also need to make sure we
invalidate when mutating style through CSSOM APIs.
Previously we would re-run the entire CSS selector machinery for each
property resolved. Instead of doing that, we now resolve a final set of
custom property key/value pairs at the start of the cascade.
- Replace "auto" with "auto const" where appropriate.
- Remove an unused struct.
- Make sort_matching_rules() a file-local static function.
- Remove some unnecessary includes.
In the ThrowCompletionOr constructors, the VERIFY statements are using
moved-from objects. We should not rely on those objects still being
valid after being moved.
