`memcpy()` and `memmove()` are functionally equivalent if the source and
destination memory regions do not overlap. If this is the case, we
should prefer `memcpy()` as it's implemented in a simpler and faster
way. As our `memcpy()` starts copying from the lowest address first,
relaxing a `memmove()` call to `memcpy()` is safe if the destination:
- starts at a lower address than the source
- starts at a higher address than the source's end
This is a preparation before we can create a usable mechanism to use
filesystem-specific mount flags.
To keep some compatibility with userland code, LibC and LibCore mount
functions are kept being usable, but now instead of doing an "atomic"
syscall, they do multiple syscalls to perform the complete procedure of
mounting a filesystem.
The FileBackedFileSystem IntrusiveList in the VFS code is now changed to
be protected by a Mutex, because when we mount a new filesystem, we need
to check if a filesystem is already created for a given source_fd so we
do a scan for that OpenFileDescription in that list. If we fail to find
an already-created filesystem we create a new one and register it in the
list if we successfully mounted it. We use a Mutex because we might need
to initiate disk access during the filesystem creation, which will take
other mutexes in other parts of the kernel, therefore making it not
possible to take a spinlock while doing this.
Since https://reviews.llvm.org/D131441, libc++ must be included before
LibC. As clang includes libc++ as one of the system includes, LibC
must be included after those, and the only correct way to do that is
to install LibC's headers into the sysroot.
Targets that don't link with LibC yet require its headers for one
reason or another must add install_libc_headers as a dependency to
ensure that the correct headers have been (re)installed into the
sysroot.
LibC/stddef.h has been dropped since the built-in stddef.h receives
a higher include priority.
In addition, string.h and wchar.h must
define __CORRECT_ISO_CPP_STRING_H_PROTO and
_LIBCPP_WCHAR_H_HAS_CONST_OVERLOADS respectively in order to tell
libc++ to not try to define methods implemented by LibC.
This is needed to avoid including LibC headers in Lagom builds.
Unfortunately, we cannot rely on the build machine to provide a
fully POSIX-compatible ELF header for Lagom builds, so we have to
use our own.
libc++ disallows including LibC's complex.h in C++ mode. This means that
a C++ file cannot expect LibC's complex.h to be included, and thus
cannot use c-prefixed complex number functions. As a result,
complex.cpp is broken when libc++ has a higher include priority
than LibC.
A check for __cplusplus has been added to complex.h to warn users of
toolchains that don't use libc++.
Change the name and return type of
`IPv6Address::to_deprecated_string()` to `IPv6Address::to_string()`
with return type `ErrorOr<String>`.
It will now propagate errors that occur when writing to the
StringBuilder.
There are two users of `to_deprecated_string()` that now use
`to_string()`:
1. `Formatted<IPv6Address>`: it now propagates errors.
2. `inet_ntop`: it now sets errno to ENOMEM and returns.
Depending on stack values being correctly and deterministically
overwritten was a bit too optimistic, to be honest. This new logic uses
a value on the heap.
Dr. POSIX says:
Although the space used by string is no longer used once a new
string which defines name is passed to putenv(), if any thread in
the application has used getenv() to retrieve a pointer to this
variable, it should not be freed by calling free(). If the changed
environment variable is one known by the system (such as the locale
environment variables) the application should never free the buffer
used by earlier calls to putenv() for the same variable.
Applications _should_ not free the data passed to `putenv`, but they
_could_ in practice. I found that our Quake II port misbehaves in this
way, but does not crash on other platforms because glibc/musl `putenv`
does not assume that environment variables are correctly formatted.
The new behavior ignores environment variables without a '=' present,
and prevents excessively reading beyond the variable's name if the data
pointed to by the environment entry does not contain any null bytes.
With this change, our Quake II port no longer crashes when switching
from fullscreen to windowed mode.
That's what this class really is; in fact that's what the first line of
the comment says it is.
This commit does not rename the main files, since those will contain
other time-related classes in a little bit.
GCC 13 produces the following true positive warnings:
- `-Wredundant-move` when trying to move `result->tooltip()`, which
is a const reference in `Assistant/main.cpp`
- `-Wuse-after-free` when freeing an environment variable before
removing it from `s_malloced_environment_variables`
- `-Wdangling-pointer` when storing an AST node's `this` pointer to the
interpreter's node stack in LibJS. This is not actually an issue, as
it is popped when the scope ends, but GCC has no way of telling this.
This is the AArch64 equivalent of `R_X86_64_IRELATIVE`, which specifies
a symbol whose address is determined by calling a local IFUNC resolver
function.
To be able to port c-ares the IN6_IS_ADDR_V4COMPAT and
various macros of the form IN6_IS_ADDR_MC_XX_LOCAL were added
as well as the IN_CLASS{A,B} macros
Instead of storing x86_64 register names in `SC_create_thread_params`,
let the Kernel figure out how to pass the parameters to
`pthread_create_helper`.
Use the new futimens syscall to ensure futimens can actually work.
This change for example allows a user to run "touch non-existing-file"
without getting any error, as expected.
It makes much more sense to have these actions being performed via the
prctl syscall, as they both require 2 plain arguments to be passed to
the syscall layer, and in contrast to most syscalls, we don't get in
these removed syscalls an automatic representation of Userspace<T>, but
two FlatPtr(s) to perform casting on them in the prctl syscall which is
suited to what has been done in the removed syscalls.
Also, it makes sense to have these actions in the prctl syscall, because
they are strongly related to the process control concept of the prctl
syscall.
The Linux `getopt_long` manpage tells users to reset `optind` to 1 when
scanning the same argument vector or a new argument vector again. This
makes sense, since `optind` denotes the _next_ option to be processed.
The behavior of setting `optind` to 0 doesn't seem to be specified
anywhere, so let's also remove that comment from `unistd.h`.
This allows us to get rid of an include to LibC/sys/ttydefaults.h in the
Kernel TTY implementation.
Also, move ttydefchars static const struct to another file called
Kernel/API/ttydefaultschars.h, so it could be used too in the Kernel TTY
implementation without the need to include anything from LibC.
This commit moves the implementation of getopt into AK, and converts its
API to understand and use StringView instead of char*.
Everything else is caught in the crossfire of making
Option::accept_value() take a StringView instead of a char const*.
With this, we must now pass a Span<StringView> to ArgsParser::parse(),
applications using LibMain are unaffected, but anything not using that
or taking its own argc/argv has to construct a Vector<StringView> for
this method.
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.
This commit adds the used relocation types to elf.h, and handles the
types in DynamicLoader and DynamicObject. No new functionalitty has to
be added, as the same code can be reused between aarch64 and x86_64.
This commit adds R_AARCH64_RELATIVE to elf.h and uses it in
ELF::perform_relative_relocations to correctly verify the relocation
type. This is the only change needed to support relative relocations for
aarch64.
