This is necessary to support the wayland protocol.
I also moved the CMSG_* macros to the kernel API since they are used in
both kernel and userspace.
this does not break ntpquery/SCM_TIMESTAMP.
Reduce inclusion of limits.h as much as possible at the same time.
This does mean that kmalloc.h is now including Kernel/API/POSIX/limits.h
instead of LibC/limits.h, but the scope could be limited a lot more.
Basically every file in the kernel includes kmalloc.h, and needs the
limits.h include for PAGE_SIZE.
Some programs explicitly ask for a different initial stack size than
what the OS provides. This is implemented in ELF by having a
PT_GNU_STACK header which has its p_memsz set to the amount that the
program requires. This commit implements this policy by reading the
p_memsz of the header and setting the main thread stack size to that.
ELF::Image::validate_program_headers ensures that the size attribute is
a reasonable value.
Previously we didn't send the SIGPIPE signal to processes when
sendto()/sendmsg()/etc. returned EPIPE. And now we do.
This also adds support for MSG_NOSIGNAL to suppress the signal.
This patch adds the NGROUPS_MAX constant and enforces it in
sys$setgroups() to ensure that no process has more than 32 supplementary
group IDs.
The number doesn't mean anything in particular, just had to pick a
number. Perhaps one day we'll have a reason to change it.
Add them in `<Kernel/API/Device.h>` and use these to provides
`{makedev,major,minor}` in `<sys/sysmacros.h>`. It aims to be more in
line with other Unix implementations and avoid code duplication in user
land.
This feature was introduced in version 4.17 of the Linux kernel, and
while it's not specified by POSIX, I think it will be a nice addition to
our system.
MAP_FIXED_NOREPLACE provides a less error-prone alternative to
MAP_FIXED: while regular fixed mappings would cause any intersecting
ranges to be unmapped, MAP_FIXED_NOREPLACE returns EEXIST instead. This
ensures that we don't corrupt our process's address space if something
is already at the requested address.
Note that the more portable way to do this is to use regular
MAP_ANONYMOUS, and check afterwards whether the returned address matches
what we wanted. This, however, has a large performance impact on
programs like Wine which try to reserve large portions of the address
space at once, as the non-matching addresses have to be unmapped
separately.
Add the `posix_madvise(..)` LibC implementation that just forwards
to the normal `madvise(..)` implementation.
Also define a few POSIX_MADV_DONTNEED and POSIX_MADV_NORMAL as they
are part of the POSIX API for `posix_madvise(..)`.
This is needed by the `fio` port.
The advices are almost always exclusive of one another, and while POSIX
does not define madvise, most other unix-like and *BSD systems also only
accept a singular value per call.
This allows userspace to trigger a full (FIXME) flush of a shared file
mapping to disk. We iterate over all the mapped pages in the VMObject
and write them out to the underlying inode, one by one. This is rather
naive, and there's lots of room for improvement.
Note that shared file mappings are currently not possible since mmap()
returns ENOTSUP for PROT_WRITE+MAP_SHARED. That restriction will be
removed in a subsequent commit. :^)
Looking at how these two constants are commonly used in other systems,
we should be able to mimic their behavior using our PT_PEEK constant.
For example, see:
https://man.netbsd.org/NetBSD-6.0.1/i386/ptrace.2
This patch begins the work of sharing types and macros between Kernel
and LibC instead of duplicating them via the kludge in UnixTypes.h.
The basic idea is that the Kernel vends various POSIX headers via
Kernel/API/POSIX/ and LibC simply #include's them to get the macros.
