The getaddrinfo(3), getipnodebyname(3) and resolver(3) can coincide now
with what should be totally reentrant, and h_errno values will now
be preserved correctly, but this does not affect interfaces such as
gethostbyname(3) which are still mostly non-reentrant.
In all of these relevant functions, the thread-safety has been pushed
down as far as it seems possible right now. This means that operations
that are selected via nsdispatch(3) (i.e. files, yp, dns) are protected
still under global locks that getaddrinfo(3) defines, but where possible
the locking is greatly reduced. The most noticeable improvement is
that multiple DNS lookups can now be run at the same time, and this
shows major improvement in performance of DNS-lookup threaded programs,
and solves the "Mozilla tab serialization" problem.
No single-threaded applications need to be recompiled. Multi-threaded
applications that reference "_res" to change resolver(3) options will
need to be recompiled, and ones which reference "h_errno" will also
if they desire the correct h_errno values. If the applications already
understood that _res and h_errno were not thread-safe and had their own
locking, they will see no performance improvement but will not
actually break in any way.
Please note that when NSS modules are used, or when nsdispatch(3)
defaults to adding any lookups of its own to the individual libc
_nsdispatch() calls, those MUST be reentrant as well.
incorrectly when encountering `large' groups (many members and/or many
long member names). The reporter tracked this down to the glibc NSS
module compatibility code (nss_compat.c): it would prematurely record
that a NSS module was finished iterating through its database in some
cases.
Two aspects are corrected:
1. nss_compat.c recorded that a NSS module was finished iterating
whenever the module reported something other than SUCCESS. The
correct logic is to continue iteration when the module reports
either SUCCESS or RETURN. The __nss_compat_getgrent_r and
__nss_compat_getpwent_r routines are updated to reflect this.
2. An internal helper macro __nss_compat_result is used to map glibc
NSS status codes to BSD NSS status codes (e.g. NSS_STATUS_SUCCESS ->
NS_SUCCESS). It provided the obvious mapping.
When a NSS routine is called with a too-small buffer, the
convention in the BSD NSS code is to report RETURN. (This is used
to implement reentrant APIs such as getpwnam_r(3).) However, the
convention in glibc for this case is to set errno = ERANGE and
overload TRYAGAIN. __nss_compat_result is updated to handle this
case.
PR: bin/60287
Reported by: Lachlan O'Dea <odela01@ca.com>
1) Fix style issues in comments.
2) Properly namespaceify changes
3) Appropriate sectioning of changes
Not changed: parenthesis around macro rvalue. That would make the additions
inconsistent with the other entries there, merely a different style violation
rather than a clear and obvious improvement so I'm going to have to disagree
with the judges on that one. If someone wishes to adjust *all* the rvalues
to conform to fully parenthesized marco rule, that would be both consistent
and reasonable but that's beyond the scope of the changes I wish to make at
this time.
as these ioctl's aren't MD. This also means they are installed in
/usr/include/dev/bktr now. Also provide compatability wrappers for
where these headers lived in 4.x.
an int constant to a long constant. This change improves consistency
in the following two ways:
1. The first 8 arguments are always passed in registers on ia64, which
by virtue of the generated code implicitly widens ints to longs and
allows the use of an 32-bit integral type for 64-bit arguments.
Subsequent arguments are passed onto the memory stack, which does
not exhibit the same behaviour and consequently do not allow this.
In practice this means that variadic functions taking pointers
and given NULL (without cast) work as long as the NULL is passed
in one of the first 8 arguments. A SIGSEGV is more likely the
result if such would be done for stack-based arguments. This is
due to the fact that the upper 4 bytes remain undefined.
2. All 64-bit platforms that FreeBSD supports, with the obvious
exception of ia64, allow 32-bit integral types (specifically NULL)
when 64-bit pointers are expected in variadic functions by way of
how the compiler generates code. As such, code that works correctly
(whether rightfully so or not) on any platform other than ia64, may
fail on ia64.
To more easily allow tweaking of the definition of NULL, this commit
removes the 12 definitions in the various headers and puts it in a
new header that can be included whenever NULL is to be made visible.
This commit fixes GNOME, emacs, xemacs and a whole bunch of ports
that I don't particularly care about at this time...
send strhash(3) off to sleep with the fishes. Nothing in our tree uses it.
It has no documentation. It is nonstandard and in spite of the filename
strhash.c and strhash.h, it lives in application namespace by providing
compulsory global symbols hash_create()/hash_destroy()/hash_search()/
hash_traverse()/hash_purge()/hash_stats() regardless of whether you
#include <strhash.h> or not. If it turns out that there is a huge
application for this after all, I can repocopy it somewhere safer and
we can revive it elsewhere. But please, not in libc!
to announce the demise of varargs support in GCC versions 3.3+ and to
direct users to stdarg.h instead.
Fall back to machine/varargs.h for older GCC versions.
Change execvp to be a wrapper around execvP. This is necessary for some
of the /rescue pieces. It may also be more generally applicable as well.
Submitted by: Tim Kientzle <kientzle@acm.org>
Approved by: Silence on arch@
