A lot of software relies on the fact that mmap and shbuf memory is
zeroed out by the kernel, so we should consider it initialized from the
shadow bit perspective as well.
Previously, we would not care if the handshake timer timed out because
the server was too slow, or because we were too slow, this caused
connections to fail when the system was under heavy load.
This patch fixes this behaviour (and closes#2843) by checking if the
timeout delay was within margin of error of the max timeout.
This patch introduces the concept of shadow bits. For every byte of
memory there is a corresponding shadow byte that contains metadata
about that memory.
Initially, the only metadata is whether the byte has been initialized
or not. That's represented by the least significant shadow bit.
Shadow bits travel together with regular values throughout the entire
CPU and MMU emulation. There are two main helper classes to facilitate
this: ValueWithShadow and ValueAndShadowReference.
ValueWithShadow<T> is basically a struct { T value; T shadow; } whereas
ValueAndShadowReference<T> is struct { T& value; T& shadow; }.
The latter is used as a wrapper around general-purpose registers, since
they can't use the plain ValueWithShadow memory as we need to be able
to address individual 8-bit and 16-bit subregisters (EAX, AX, AL, AH.)
Whenever a computation is made using uninitialized inputs, the result
is tainted and becomes uninitialized as well. This allows us to track
this state as it propagates throughout memory and registers.
This patch doesn't yet keep track of tainted flags, that will be an
important upcoming improvement to this.
I'm sure I've messed up some things here and there, but it seems to
basically work, so we have a place to start! :^)
LibPThread: mark pthread_exit a noreturn function using compiler attributes
LibThread: remove a call to pthread_exit from Thread::start lambda expression
as it make the return of teh lambda unreachable.
This allows us to determine which mode to render the page in.
Exposes "doctype" and "compatMode" on Document.
Exposes "name", "publicId" and "systemId" on DocumentType.
ControlBoxButton consolidates the paint_event for buttons
used in composite box widgets like ComboBox and SpinBox. Its
button bitmaps are built with create_from_ascii like WindowFrame
and ScrollBar controls, making theming more uniform.
These were not recording the higher part of the result correctly.
Since the flags are much less complicated than the inline assembly
here, just implement IMUL in C++ instead.
I totally forgot about the C++ basics here. There are three distinct
types: "char", "signed char" and "unsigned char". Whether "char" is
signed or unsigned is implementation specific.
With this, System Monitor has "System Monitor" instead of
"SystemMonitor" as tooltip, matching the app's title bar
and menu bar title.
Same for File Manager and Text Editor.
If we add "(Not responding)" to the title of an unresponsive window,
the title rect needs to be wider or we'll have text-on-stripes.
Thanks to @SharpOB for reporting this bug!
