We are compiling with `-std=c++2a` and we are using some C++20 features,
e.g. in Kernel/VM/Region.h
bool m_shared : 1 { false };
bool m_user_accessible : 1 { false };
bool m_cacheable : 1 { false };
bool m_stack : 1 { false };
bool m_mmap : 1 { false };
Now that we have SystemServer that can (re)spawn the Shell, we don't need a
separate server just for that.
The two shells (on tty0 and tty1) are configured to only be started when booting
in text mode. This means you can now simply say boot_mode=text on the kernel
command line, and SystemServer will set up the system and spawn a comfy root
shell for you :^)
Together, they replace the old text_debug option.
* boot_mode should be either "graphical" (the default) or "text". We could
potentially support other values here in the future.
* init specifies which userspace process the kernel should spawn to bootstrap
userspace. By default, this is SystemServer, but you can specify e.g.
init=/bin/Shell to run system diagnostics.
Adds more TLS 1.2 error descriptions according to the specification:
https://tools.ietf.org/html/rfc5246#section-7.2.2
This changes the DecryptionFailed description, as the specification
says that this alert should NEVER be sent by a compliant server.
Instead of creating extremely common FlyStrings like "id" and "class"
on demand every time they are needed, we now have AttributeNames.h,
which provides Web::HTML::AttributeNames::{id,class_}
This avoids a bunch of string allocations during selector matching.
Instead of string splitting every time you call Element::has_class(),
we now split the "class" attribute value when it changes, and cache
the individual classes as FlyStrings in Element::m_classes.
This makes has_class() significantly faster and moves the pain point
of selector matching somewhere else.
Sometimes people put a '}' where it doesn't belong, or various other
things go wrong. 99% of the time, it's our fault, but either way,
this patch makes us not crash or infinite-loop in some common cases.
The real solution here is to write a proper CSS lexer-parser according
to the language spec, this is just a hack fix to make more sites load
at all.
We now implement the somewhat fuzzy shrink-to-fit algorithm when laying
out inline-block elements with both block and inline children.
Shrink-to-fit works by doing two speculative layouts of the entire
subtree inside the current block, to compute two things:
1. Preferred minimum width: If we made a line break at every chance we
had, how wide would the widest line be?
2. Preferred width: We break only when explicitly told to (e.g "<br>")
How wide would the widest line be?
We then shrink the width of the inline-block element to an appropriate
value based on the above, taking the available width in the containing
block into consideration (sans all the box model fluff.)
To make the speculative layouts possible, plumb a LayoutMode enum
throughout the layout system since it needs to be respected in various
places.
Note that this is quite hackish and I'm sure there are smarter ways to
do a lot of this. But it does kinda work! :^)
In step 4 of the "renstruct the active formatting elements" algorithm it
says:
Rewind: If there are no entries before entry in the list of active
formatting elements, then jump to the step labeled create.
Prior to this patch, the implementation accorded to the spec only for
the first loop iteration.
We just look at $TERM and refuse to emit any escape sequences if it
doesn't start with "xterm".
This could be made much better, at detecting, and at not caling
getline().
This was causing very tall lines on many websites. We can now see the
section header thingy on google.com (although it's broken into lines
where it should not be..) :^)
Our current configuration clang-format allows both of these styles:
------------------
class A : B
, C {
-----------------
class A
: B
, C {
------------------
I was not able to find a setting of clang-format to only allow the
latter style (or disallow the first style), but let's at least be
consistent with the style within a file.
- initializing m_line_column to 1 in the lexer results in incorrect
column values in tokens on the first line of input.
- not incrementing m_line_column when EOF is reached results in
an incorrect column value on the last token.
This util function on the Error struct will take the source and then
returns a string like this based on line and column information it has:
foo bar
^
Which can be shown in the repl for syntax errors :^)
This is a bit annoying when running the js REPL as part of the Lagom
build, as it prints the error twice to the same terminal - once from
dbg() and then from printf().
Long term this should probably be removed completely and each program
take care itself of printing stacktraces to an appropriate location.
And move canonicalized_path() to a static method on LexicalPath.
This is to make it clear that FileSystemPath/canonicalized_path() only
perform *lexical* canonicalization.
* In some cases, we can first call sigaction()/signal(), then *not* pledge
sigaction.
* In other cases, we pledge sigaction at first, call sigaction()/signal()
second, then pledge again, this time without sigaction.
* In yet other cases, we keep the sigaction pledge. I suppose these could all be
migrated to drop it or not pledge it at all, if somebody is interested in
doing that.
You now have to pledge "sigaction" to change signal handlers/dispositions. This
is to prevent malicious code from messing with assertions (and segmentation
faults), which are normally expected to instantly terminate the process but can
do other things if you change signal disposition for them.
It's not enough to send ourselves a SIGABRT, as it may be ignored or handled
differently. We really, really want abort() to never return, as that will mess
up the assumptions of the calling code big time. So, if raise(SIGABRT) returns,
kill ourselves with SIGKILL, and if that somehow returns too, call _exit().
An alternative approach, which glibc apparently follows, is to reset SIGABRT
disposition to its default value and then send SIGABRT to yourself a second
time. That would also work, but I believe SIGKILL + _exit() to be a simpler
approach that is less likely to break in extremely weird situations.
Note that this only guarantees that abort() never returns, not that the process
actually gets killed. It's still possible to install a SIGABRT handler that
simply never returns (such as by longjmp'ing out, endlessly looping, or exec'ing
another image). That is a legitimate use case we want to support; at the same
time most software doesn't use that functionality and would benefit from hard
guarantees that abort() terminates the program. The following commit is going to
introduce means for ensuring SIGABRT handler is never reset to something
unexpected.
The CMake runner looks at the return code if you don't set
the pattern. Since the AK test suite setup doesn't use return
codes, we were missing test failures.
