This commit adds a basic implementation of
the ptrace syscall, which allows one process
(the tracer) to control another process (the tracee).
While a process is being traced, it is stopped whenever a signal is
received (other than SIGCONT).
The tracer can start tracing another thread with PT_ATTACH,
which causes the tracee to stop.
From there, the tracer can use PT_CONTINUE
to continue the execution of the tracee,
or use other request codes (which haven't been implemented yet)
to modify the state of the tracee.
Additional request codes are PT_SYSCALL, which causes the tracee to
continue exection but stop at the next entry or exit from a syscall,
and PT_GETREGS which fethces the last saved register set of the tracee
(can be used to inspect syscall arguments and return value).
A special request code is PT_TRACE_ME, which is issued by the tracee
and causes it to stop when it calls execve and wait for the
tracer to attach.
FlyString is a flyweight string class that wraps a RefPtr<StringImpl>
known to be unique among the set of FlyStrings. The class is very
unoptimized at the moment.
When to use FlyString:
- When you want O(1) string comparison
- When you want to deduplicate a lot of identical strings
When not to use FlyString:
- For strings that don't need either of the above features
- For strings that are likely to be unique
A new IP address or a new network mask can be specified in the command
line arguments of ifconfig to replace the old values of a given network
adapter. Additionally, more information is being printed for each adapter.
Add an extra out-parameter to shbuf_get() that receives the size of the
shared buffer. That way we don't need to make a separate syscall to
get the size, which we always did immediately after.
This feels a lot more consistent and Unixy:
create_shared_buffer() => shbuf_create()
share_buffer_with() => shbuf_allow_pid()
share_buffer_globally() => shbuf_allow_all()
get_shared_buffer() => shbuf_get()
release_shared_buffer() => shbuf_release()
seal_shared_buffer() => shbuf_seal()
get_shared_buffer_size() => shbuf_get_size()
Also, "shared_buffer_id" is shortened to "shbuf_id" all around.
This patch adds a crappy pread() just to get "git" working locally.
A proper version would be implemented in the kernel so that we don't
have to mess with the file descriptor's offset at all.
This allows RefPtr to be stored in a HashTable<RefPtr<T>> :^)
It's unfortunate about the const_casts. We'll need to fix HashMap::get
to play nice with non-const Traits<T>::PeekType at some point.
We now allocate 64KB at a time and divide them into chunks for handing
out to malloc() callers. This significantly reduces the number of
system calls made due to memory allocation.
This yields a ~15% speedup when compiling Process.cpp inside SerenityOS
(down from 24 sec to 20 sec on my machine.)
There's more performance on the table here, no doubt.
This reverts commit 4e79a60b78.
This broke the GCC port. Apparently isblank() was added in C99 and for
some reason it needs special treatment in headers.
You can now #include <AK/Forward.h> to get most of the AK types as
forward declarations.
Header dependency explosion is one of the main contributors to compile
times at the moment, so this is a step towards smaller include graphs.
Calling shutdown prevents further reads and/or writes on a socket.
We should do a few more things based on the type of socket, but this
initial implementation just puts the basic mechanism in place.
Work towards #428.
This makes getting a pseudoterminal pair a little bit more portable.
Note that grantpt() and unlockpt() are currently no-ops, since we've
already granted the pseudoterminal slave to the calling user.
We also accept O_CLOEXEC to posix_openpt(), unlike some systems. :^)
