for pthread_* support. Major changes:
* Valgrind now contains a (skeletal!) user-space pthreads
implementation. The exciting bits are in new file vg_scheduler.c.
This contains thread management and scheduling, including nasty crud
to do with making some syscalls (read,write,nanosleep) nonblocking.
Also implementation of pthread_ functions: create join
mutex_{create,destroy,lock,unlock} and cancel.
* As a side effect of the above, major improvements to signal handling
and to the client-request machinery. This is now used to intercept
malloc/free etc too; the hacky way this is done before is gone.
Another side effect is that vg_dispatch.S is greatly simplified.
Also, the horrible hacks to do with delivering signals to threads
blocked in syscalls are gone, since the new mechanisms cover this case
easily.
git-svn-id: svn://svn.valgrind.org/valgrind/trunk@52
