PERFORCE change 55970 for review

[Marcel Moolenaar]

On Mon, Jun 28, 2004 at 02:27:08PM +0800, David Xu wrote:
> 
> OK, I am glad to see you are working on libthread_db, but
> I have already a libthread_db tree in ksedbg branch.

I know. My focus is different. I don't care so much about libthread_db
itself at the moment. My focus is on finding the best possible way
to make it all work with the debugger. This includes core dumps, the
proc services, ptrace and libthread_db. I need to play around with it
all to understand what we need to do where and what it is that's being
provided. Then I know how and what we need to add where.

We may not need a ttrace(2) syscall for example. We can have ptrace(2)
accept lwpids as well as pids and have it do the right thing. Also, as
I've told you before, ttrace(2) is not standard, but it's something
that already exists. We need to decide whether we want to be compatible
with the HP-UX implementation and to what extend.

I also found ways to preserve compatibility with RELENG_4, so that
we can use gdb 6.1.1 with libthread_db on 4.x core files. This only
needs to apply to libc_r of course.

> I am current making libthread_db.so in two levels:
> the first level is a umbrella, the second level is a driver,
> every thread library will have a driver, I found you were trying
> to mix three thread libraries code into in same functions,
> things like following code looks strange for me, how can you
> include three different thr_pirvate.h in same .c, and compile
> them ?

I don't include any private headers. I'm merely taking advantage of
how the libc_r support was written. See
src/gnu/usr.bin/binutils/gdb/freebsd-uthread.c

Note that although cross-debugging is not something I'm focussed on,
I try to avoid depending too much on native (private) headers. This
at least keeps the option open for as much as possible.

Anyway: I don't care about which libthread_db is eventually going to
be used. I just need the stuff the play around with.

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel at xcllnt.net