ISO C requires in section 7.2:
The assert macro is redefined according to the current state of NDEBUG
each time that <assert.h> is included.
Also add tests for `assert` multiple inclusion accordingly.
As a small cleanup, this also makes `page_round_up` verify its
precondition with `page_round_up_would_wrap` (which callers are expected
to call), rather than having its own logic.
Fixes#11297.
The actual length of the resulting string is encoded in the return
value; treating the entire buffer as a string leads to reading
uninitialized memory.
Most other syscalls pass address arguments as `void*` instead of
`uintptr_t`, so let's do that here too. Besides improving consistency,
this commit makes `strace` correctly pretty-print these arguments in
hex.
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.
This error only ever gets propagated to the userspace if
MAP_FIXED_NOREPLACE is requested, as MAP_FIXED unmaps intersecting
ranges beforehand, and non-fixed mmap() calls will just fall back to
allocating anywhere.
Linux specifies MAP_FIXED_NOREPLACE to return EEXIST when it can't
allocate, we now match that behavior.
No need to copy and move them around, just to pass them as a
`String const&` to the constructor.
We still end up copying it to a normal String in the end though...
Previously we were assigning to Process::m_space before actually
entering the new address space (assigning it to CR3.)
If a thread was preempted by the scheduler while destroying the old
address space, we'd then attempt to resume the thread with CR3 pointing
at a partially destroyed address space.
We could then crash immediately in write_cr3(), right after assigning
the new value to CR3. I am hopeful that this may have been the bug
haunting our CI for months. :^)
Instead, wait until we transition back to userspace. This stops
userspace from being able to suspend a thread indefinitely while it's
running in kernelspace (potentially holding some blocking mutex.)
PVS Studio static analysis noticed we didn't initialize these in a
bunch of cases. This change fixes that so we will always initialize
these using universal initialization.
fio allows you to test various different IO subsystems and patterns.
It can help us test and benchmark the I/O subsystems of Serenity.
This port gets the fio bootstrapped and working, using the included
.fio file, I have been able to test the file I/O performance already.
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.
These 2 members are required by POSIX and are also used by some ports.
Zero is a valid value for both of these, so no further work to support
them is required.
The general idea when ENABLE_UNICODE_DATABASE_DOWNLOAD is OFF has been
that the Intl APIs will provide obviously incorrect results, but should
not crash. This regressed a bit with NumberFormat and DateTimeFormat.
The old patch to define `HAVE_SIGSET_T` is no longer needed, as we now
have implementations for `sigwaitinfo` and `sigtimedwait`.
Instead, for the same reason, we now have to remove a reference to
`si_errno`, which we haven't implemented yet but is just assumed to be
there.
