One bug was relatively harmless (select's timeout had an uninitialized
tv_usec), the other I'm not so sure.. (neglected to catch select returns
less than zero). Both of these were irrelevant on kernels with poll().
chunks of res_comp.c and replacing it with chunks of bind-8.1.1's resolver
code. (There are no interface changes though)
The other parts are better bounds checking related.
an unimplemented syscall returned ENOSYS, rather than EINVAL. I have run
statically linked code with this wrapper and it does appear to work fine
on 2.2-stable which doesn't have poll(). ktrace shows the poll syscall fail
once and the fallback to select() working.
if necessary. This removes the need to malloc large fd_set's for selecting
on high fd's (larger than FD_SETSIZE at libc compile time).
The syscall adaptive stuff only happens on the very first call. SIGSYS
is masked, and if the call to poll fails with ENOSYS, then we use select
for the life of the program. If poll does not fail with ENOSYS, then we
always use poll and skip the once-off signal masking gunk.
This may be overkill, but it saved my neck a few times while working on
multiple different sets of kernel sources, some with poll, some without.
Only call malloc() if the fd is too big for the compiled in fd_set size,
and don't use calloc either. This should reduce the impact of conflicts
with private malloc implementations etc. When using the fd_set on the
stack, only zero what is needed rather than all 1024 bits like FD_ZERO did.
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
routines from contrib/bind directly. There were too many problems,
including having to add -DUSE_OPTIONS_H to the entire libc source in
order for the contrib code to pick up it's options, and so on.
Instead, I've merged the changes, libc is now self contained again.
Note that this was done by selective patching from diffs, to not conflict
with the 4.4bsd base code.. This was *not* a trivial task.. I have been
testing this code (apart from cosmetic changes) in my libc for a while now.
Obtained from: Paul Vixie <paul@vix.com>
