a proclist and call the specified function for each of them.
primarily to fix a procfs locking problem, but i think that it's useful for
others as well.
while i'm here, introduce PROCLIST_FOREACH macro, which is similar to
LIST_FOREACH but skips marker entries which are used by proclist_foreach_call.
itself needs to be translated. It means that we must translate it in
every system call using it: recvfrom, sendto, connect, accept, bind,
getpeername, getsockname.
library call). Programs such as ifconfig or XFree86 4.4 XDarwin use it.
The emulation is not complete, as ifconfig is not able to display inet6
addresses correctly.
This areas is called the comm pages. It is used to provide fast access to
several data and functions.
The comm pages are mapped starting at 0xffff800 (address chosed so that
absolute branch can be used, so it can be accessed even when dynamic linking
is not ready). NetBSD has the user stack here, so we need to provide a
Darwin-specific stack setup routine which sets the top of the stack at
0xbfff0000.
This implementation is not complete but it does enough to get MacOS X.3
starting again (static binaries run, dynamic binaries still have an issue).
in the comm pages functions, we only implement bcopy, pthread_self and
memcpy.
TODO:
- clean up the powerpc specific code from MD parts
- for now we map only one page to avoid a crash, we want two pages.
- write all the comm functions.
emul.darwin.init.pid instead of emul.darwin.init_pid, and so on.
This breaks backward compatibility with the pre-dynamic sysctl(8) for
emul.darwin, but it has never been available in a formal release, so
it should be alright.
remote process. This new implementation also passes all the test programs
I've written so far.
- When exceptions come from traps, no UNIX signal should evet be sent.
- Add a lock to ensure a debugger handles only one exception at a time
- Use a structure to hold flavor and behavior in exception ports, instead
of stuffing the two argument into an int.
- Implement new Mach services: thread_suspend, thread_resume and thread_abort
- Implement Darwin's ptrace PT_ATTACHEXC and PT_THUPDATE commands
- Handle NULL second argument correctly in sigprocmask.
- One mistake in the last commit (darwin_tracesig prototype)
fit what it does.
The softsignal feature is used in Darwin to trace processes. When the
traced process gets a signal, this raises an exception. The debugger will
receive the exception message, use ptrace with PT_THUPDATE to pass the
signal to the child or discard it, and then it will send a reply to the
exception message, to resume the child.
With the hook at the beginnng of kpsignal2, we are in the context of the
signal sender, which can be the kill(1) command, for instance. We cannot
afford to sleep until the debugger tells us if the signal should be
delivered or not.
Therefore, the hook to generate the Mach exception must be in the traced
process context. That was we can sleep awaiting for the debugger opinion
about the signal, this is not a problem. The hook is hence located into
issignal, at the place where normally SIGCHILD is sent to the debugger,
whereas the traced process is stopped. If the hook returns 0, we bypass
thoses operations, the Mach exception mecanism will take care of notifying
the debugger (through a Mach exception), and stop the faulting thread.
david