Also let's settle on calling the operation of fetching the "this" value
from the Interpreter and converting it to a specific Object pointer
typed_this() since consistency is nice.
To make sure that everything is set up correctly in objects before we
start adding properties to them, we split cell allocation into 3 steps:
1. Allocate a cell of appropriate size from the Heap
2. Call the C++ constructor on the cell
3. Call initialize() on the constructed object
The job of initialize() is to define all the initial properties.
Doing it in a second pass guarantees that the Object has a valid Shape
and can find its own GlobalObject.
More work towards supporting multiple global objects. Native C++ code
now get a GlobalObject& and don't have to ask the Interpreter for it.
I've added macros for declaring and defining native callbacks since
this was pretty tedious and this makes it easier next time we want to
change any of these signatures.
posix_spawn() tries to present semantics as if no fork() is happening
behind the scenes, so running arbitrary atexit handlers of the parent
in the child seems like the wrong thing to do.
It looks like they're considered a bad idea, so let's not add
them before we need them. I figured it's good to have them in
git history if we ever do need them though, hence the add/remove
dance.
Add seteuid()/setegid() under _POSIX_SAVED_IDS semantics,
which also requires adding suid and sgid to Process, and
changing setuid()/setgid() to honor these semantics.
The exact semantics aren't specified by POSIX and differ
between different Unix implementations. This patch makes
serenity follow FreeBSD. The 2002 USENIX paper
"Setuid Demystified" explains the differences well.
In addition to seteuid() and setegid() this also adds
setreuid()/setregid() and setresuid()/setresgid(), and
the accessors getresuid()/getresgid().
Also reorder uid/euid functions so that they are the
same order everywhere (namely, the order that
geteuid()/getuid() already have).
Previously 4 bytes at once were read and compared to the string
"DATA". This worked when the DATA marker was aligned on a 32-bit
boundary relative to the start of the file. However, this is not
guranteed to always be the case, and for some files the loader
would just keep searching for the marker.
The stacking context tree doesn't affect layout at all, so let's move
it into the Painting/ directory. I'm not sure yet if it's worth going
for a fullly separate painting tree. So far I'm thinking a stacking
context tree with pointers into the layout tree might be enough.
"Paint" matches what we call this in the rest of the system. Let's not
confuse things by mixing paint/render/draw all the time. I'm guilty of
this in more places..
Also rename RenderingContext => PaintContext.
The shrink-to-fit width algorithm actually works a little bit different
in the absolute positioning context, so it can't share all of its code
with non-absolute positioning.
Also, inline-block elements were always inserting unnecessary line
breaks when splitting, which caused the preferred width to be smaller
than it should be. This patch fixes that as well, by just not breaking
after inline-block elements in LayoutMode::OnlyRequiredLineBreaks.
CSS defines a very specific paint order. This patch starts steering us
towards respecting that by introducing the PaintPhase enum with values:
- Background
- Border
- Foreground
- Overlay (internal overlays used by inspector)
Basically, to get the right visual result, we have to render the page
multiple times, going one phase at a time.
All the file actions stuff is still missing for now,
as is POSIX_SPAWN_SETSCHEDULER (not sure what that's
supposed to do) and POSIX_SPAWN_RESETIDS.
Implemented in userspace for now. Once there are users,
it'll likely make sense to make this a syscall for
performance reasons.
A simple test program of the form
extern char **environ;
int main(int argc, char* argv[])
{
pid_t pid;
char* args[] = { "ls", NULL };
posix_spawnp(&pid, "ls", nullptr, nullptr, args, environ);
}
works fine.
We were getting a little overly memey in some places, so let's scale
things back to business-casual.
Informal language is fine in comments, commits and debug logs,
but let's keep the runtime nice and presentable. :^)
This is a convenient wrapper around readlink() that hides away the details
of buffers and buffer sizes, and simply returns a String. The best part is it
doesn't rely on PATH_MAX :D
It comes in two versions, for Serenity, where we can pass non-null-terminated
strings to syscalls, and where sys$readlink() returns the total link size, and
for other systems, where we have to copy out the string, and always have to do
two syscalls.
That's not how readlink() is supposed to work: it should copy as many bytes
as fit into the buffer, and return the number of bytes copied. So do that,
but add a twist: make sys$readlink() actually return the whole size, not
the number of bytes copied. We fix up this return value in userspace, to make
LibC's readlink() behave as expected, but this will also allow other code
to allocate a buffer of just the right size.
Also, avoid an extra copy of the link target.
The more generic virtual variant is renamed to node_name() and now only
Element has tag_name(). This removes a huge amount of String ctor/dtor
churn in selector matching.