This wasn't much of a problem before because copying the ByteBuffer
merely copied the RefPtr but now that ByteBuffer behaves like Vector
this causes unnecessary allocations.
This non-POSIX header is used in Linux/BSD systems for storing the
default termios settings. This lets us setup new TTYs' `m_termios.c_cc`
in a nicer way than using a magic string.
Bytes in the 0x80..0x9F range were treated as C1 control codes,
which prevented them from being parsed as UTF-8 bytes.
This caused some characters (like U+DF, encoded as 0xC3 0x9F)
from being recognized as printable characters.
Since we now store intermediate characters separately, the intermediates
should be checked for the presence of the '?' DEC private marker, not
the first parameter.
This commit replaces the former, hand-written parser with a new one that
can be generated automatically according to a state change diagram.
The new `EscapeSequenceParser` class provides a more ergonomic interface
to dealing with escape sequences. This interface has been inspired by
Alacritty's [vte library](https://github.com/alacritty/vte/).
I tried to avoid changing the application logic inside the `Terminal`
class. While this code has not been thoroughly tested, I can't find
regressions in the basic command line utilities or `vttest`.
`Terminal` now displays nicer debug messages when it encounters an
unknown escape sequence. Defensive programming and bounds checks have
been added where we access parameters, and as a result, we can now
endure 4-5 seconds of `cat /dev/urandom`. :D
We generate EscapeSequenceStateMachine.h when building the in-kernel
LibVT, and we assume that the file is already in place when the userland
library is being built. This will probably cause problems later on, but
I can't find a way to do it nicely.
By constraining two implementations, the compiler will select the best
fitting one. All this will require is duplicating the implementation and
simplifying for the `void` case.
This constraining also informs both the caller and compiler by passing
the callback parameter types as part of the constraint
(e.g.: `IterationFunction<int>`).
Some `for_each` functions in LibELF only take functions which return
`void`. This is a minimal correctness check, as it removes one way for a
function to incompletely do something.
There seems to be a possible idiom where inside a lambda, a `return;` is
the same as `continue;` in a for-loop.
Previously, all sorts of weird stuff would happen when the editor was at
the last line of the terminal (or when the printed line would be at the
last line), this commit makes the editor scroll the terminal up before
trying to write to a row that doesn't actually exist (yet).
This fixes ^R search making a mess when initiated at the last line
(especially with multiline prompts).
This implements different blend modes in the SoftwareRasterizer by
first setting up the blend factors then rendering the pixels into a
temporary buffer and finally mixing the contents of the temporary buffer
with the contents of the backbuffer based on the blend factors.
After this commit, Parser::index_of_node_at will prefer to return nodes
with greater indices.
Since the parsing logic ensures that child nodes come after parent
nodes, this change makes this function return child nodes when possible.
This implements the macOS API malloc_good_size() which returns the
true allocation size for a given requested allocation size. This
allows us to make use of all the available memory in a malloc chunk.
For example, for a malloc request of 35 bytes our malloc would
internally use a chunk of size 64, however the remaining 29 bytes
would be unused.
Knowing the true allocation size allows us to request more usable
memory that would otherwise be wasted and make that available for
Vector, HashTable and potentially other callers in the future.
The checkerboard pattern used in transparency backgrounds was sometimes
misaligned with the grid. This happened because it was incorrectly
anchoring the pattern to the clipped rect instead of the global
grid of the underlying paint target.
This code path is very hot, and since we're seeing a lot of the same
strings repeatedly (and they're heading into a FlyString for storage)
let's construct those using FlyString(StringView) to avoid temporary
String objects.
For whatever reason, symbolication was doing an O(n) walk of all the
symbols, despite having sorted them beforehand.
Changing this to a binary_search() makes symbolication noticeably
faster and improves Profiler startup time.
We were using ELF::Image::section(0) to indicate the "undefined"
section, when what we really wanted was just Optional<Section>.
So let's use Optional instead. :^)
The function fstatat can do the same thing as the stat and lstat
functions. However, it can be passed the file descriptor of a directory
which will be used when as the starting point for relative paths. This
is contrary to stat and lstat which use the current working directory as
the starting for relative paths.
It's technically not specified by POSIX, but it appears most Unix-like
systems worth mentioning put those definitions there. Also, it's more
logical since the dev_t type is defined there.
Previously you could pass anything (e.g a text file) to ImageDecoder and
it would "succeed" in decoding it and give you back a 0-frame result.
Let's consider that state a failure instead.
