It emerges that libreadline doesn't notice terminal window size change
events unless they occur while collecting input. This is easy to stumble
over if you resize the window while using a pager to look at query output,
but it can be demonstrated without any pager involvement. The symptom is
that queries exceeding one line are misdisplayed during subsequent input
cycles, because libreadline has the wrong idea of the screen dimensions.
The safest, simplest way to fix this is to call rl_reset_screen_size()
just before calling readline(). That causes an extra ioctl(TIOCGWINSZ)
for every command; but since it only happens when reading from a tty, the
performance impact should be negligible. A more valid objection is that
this still leaves a tiny window during entry to readline() wherein delivery
of SIGWINCH will be missed; but the practical consequences of that are
probably negligible. In any case, there doesn't seem to be any good way to
avoid the race, since readline exposes no functions that seem safe to call
from a generic signal handler --- rl_reset_screen_size() certainly isn't.
It turns out that we also need an explicit rl_initialize() call, else
rl_reset_screen_size() dumps core when called before the first readline()
call.
rl_reset_screen_size() is not present in old versions of libreadline,
so we need a configure test for that. (rl_initialize() is present at
least back to readline 4.0, so we won't bother with a test for it.)
We would need a configure test anyway since libedit's emulation of
libreadline doesn't currently include such a function. Fortunately,
libedit seems not to have any corresponding bug.
Merlin Moncure, adjusted a bit by me
Per buildfarm member anchovy, 2.6.0 exists in the wild now.
Hopefully it works with Postgres; if not, we'll have to do something
about that, but in any case claiming it's "too old" is pretty silly.
xlc provides "long long" unconditionally at C99-compatible language
levels, and this option provokes a warning. The warning interferes with
"configure" tests that fail in response to any warning. Notably, before
commit 85a2a8903f7e9151793308d0638621003aded5ae, it interfered with the
test for -qnoansialias. Back-patch to 9.0 (all supported versions).
Expose PG_VERSION_NUM (e.g., "90600") as a Make variable; but for
consistency with the other Make variables holding similar info,
call the variable just VERSION_NUM not PG_VERSION_NUM.
There was some discussion of making this value available as a pg_config
value as well. However, that would entail substantially more work than
this two-line patch. Given that there was not exactly universal consensus
that we need this at all, let's just do a minimal amount of work for now.
Back-patch of commit a5d489ccb7e613c7ca3be6141092b8c1d2c13fa7, so that this
variable is actually useful for its intended purpose sometime before 2020.
Michael Paquier, reviewed by Pavel Stehule
According to recent tests, this case now works fine, so there's no reason
to reject it anymore. (Even if there are still some OpenBSD platforms
in the wild where it doesn't work, removing the check won't break any case
that worked before.)
We can actually remove the entire test that discovers whether libpython
is threaded, since without the OpenBSD case there's no need to know that
at all.
Per report from Davin Potts. Back-patch to all active branches.
Darwin --enable-nls builds use a substitute setlocale() that may start a
thread. Buildfarm member orangutan experienced BackendList corruption
on account of different postmaster threads executing signal handlers
simultaneously. Furthermore, a multithreaded postmaster risks undefined
behavior from sigprocmask() and fork(). Emit LOG messages about the
problem and its workaround. Back-patch to 9.0 (all supported versions).
With OpenLDAP versions 2.4.24 through 2.4.31, inclusive, PostgreSQL
backends can crash at exit. Raise a warning during "configure" based on
the compile-time OpenLDAP version number, and test the crash scenario in
the dblink test suite. Back-patch to 9.0 (all supported versions).
This function is pervasive on free software operating systems; import
NetBSD's implementation. Back-patch to 8.4, like the commit that will
harness it.
Usually the search would find plain "tclsh" without any trouble,
but some installations might only have the version-numbered flavor
of that program.
No compatibility problems have been reported with 8.6, so we might
as well back-patch this to all active branches.
Christoph Berg
This test used to just define an unused static inline function and check
whether that causes a warning. But newer clang versions warn about
unused static inline functions when defined inside a .c file, but not
when defined in an included header, which is the case we care about.
Change the test to cope.
Andres Freund
The configure script's test for <sys/ucred.h> did not work on OpenBSD,
because on that platform <sys/param.h> has to be included first.
As a result, socket peer authentication was disabled on that platform.
Problem introduced in commit be4585b1c27ac5dbdd0d61740d18f7ad9a00e268.
Andres Freund, slightly simplified by me.
Some versions of libedit expose bogus definitions of setproctitle(),
optreset, and perhaps other symbols that we don't want configure to pick up
on. There was a previous report of similar problems with strlcpy(), which
we addressed in commit 59cf88da91bc88978b05275ebd94ac2d980c4047, but the
problem has evidently grown in scope since then. In hopes of not having to
deal with it again in future, rearrange configure's tests for supplied
functions so that we ignore libedit/libreadline except when probing
specifically for functions we expect them to provide.
Per report from Christoph Berg, though this is slightly more aggressive
than his proposed patch.
We previously supposed that any given platform would supply both or neither
of these functions, so that one configure test would be sufficient. It now
appears that at least on AIX this is not the case ... which is likely an
AIX bug, but nonetheless we need to cope with it. So use separate tests.
Per bug #6758; thanks to Andrew Hastie for doing the followup testing
needed to confirm what was happening.
Backpatch to 9.1, where we began using these functions.
We had put a test for libxml2's xmlStructuredErrorContext variable in
configure, but of course that doesn't work on Windows builds. The next
best alternative seems to be to test the LIBXML_VERSION symbol provided
by xmlversion.h.
Per report from Talha Bin Rizwan, though this fixes it in a different way
than his proposed patch.
The BSD-ish members of the buildfarm all seem to think removing this
was a bad idea. It looks to me like it resulted in omitting the system
header inclusion necessary to detect the fields of struct tm correctly.
ENABLE_DTRACE unused as of a7b7b07af340c73adee9959edf260695591a9496
HAVE_ERR_SET_MARK unused as of 4ed4b6c54e5fab24ab2624d80e26f7546edc88ad
HAVE_FCVT unused as of 4553e1d80f824291932cfde30aa24a76dd8f1941
HAVE_STRUCT_SOCKADDR_UN unused as of b4cea00a1fc9d2270bfe9aeeee44915378d5f733
HAVE_SYSCONF unused as of f83356c7f574bc69969f29dc7b430b286a0cd9f4
TM_IN_SYS_TIME never used, obsolescent per Autoconf documentation
These were apparently never used. The AC_SUBST was probably just
added in a copy-and-paste manner. (The shell variables continue to be
used inside configure. The change is just that we don't need them
outside of configure.)
Remove the following ports:
- dgux
- nextstep
- sunos4
- svr4
- ultrix4
- univel
These are obsolete and not worth rescuing. In most cases, there is
circumstantial evidence that they wouldn't work anymore anyway.
PGAC_PATH_COLLATEINDEX supposed that it could use AC_PATH_PROGS to search
for collateindex.pl, but that macro will only accept files that are marked
executable, and at least some DocBook installations don't mark the script
executable (a case the docs Makefile was already prepared for). Accept the
script if it's present and readable in $DOCBOOKSTYLE/bin, and otherwise
search the PATH as before.
Having fixed that up, we don't need the fallback case that was in the docs
Makefile, and instead can throw an understandable error if configure didn't
find the script. Per recent trouble report from John Lumby.
In the Fedora variant of MinGW, the openssl libraries have their normal
names, not libeay32 and libssleay32. Adjust configure probes to allow
that, per bug #6486.
Tomasz Ostrowski
The immediate impetus for this is that Noah Misch's patch to elide
unnecessary table and index rebuilds when changing typmod for temporal
types uses it; and this is extracted from that patch, with some
further commentary by me. But it seems logically separate from the
remainder of the patch, so I'm committing it separately; this is not
the first time someone has wanted fls() in the backend and probably
won't be the last.
If we end up using this in more performance-critical spots it may be
worthwhile to add some architecture-specific optimizations to our
src/port version of fls() - e.g. any x86 platform can implement this
using the assembly instruction BSRL. But performance won't matter
a bit for assessing typmod changes, so I'm not worried about that
right now.
Historically we've used the SWPB instruction for TAS() on ARM, but this
is deprecated and not available on ARMv6 and later. Instead, make use
of a GCC builtin if available. We'll still fall back to SWPB if not,
so as not to break existing ports using older GCC versions.
Eventually we might want to try using __sync_lock_test_and_set() on some
other architectures too, but for now that seems to present only risk and
not reward.
Back-patch to all supported versions, since people might want to use any
of them on more recent ARM chips.
Martin Pitt
The hint bit makes for a small but measurable performance improvement
in access to contended spinlocks.
On the other hand, some PPC chips give an illegal-instruction failure.
There doesn't seem to be a completely bulletproof way to tell whether the
hint bit will cause an illegal-instruction failure other than by trying
it; but most if not all 64-bit PPC machines should accept it, so follow
the Linux kernel's lead and assume it's okay to use it in 64-bit builds.
Of course we must also check whether the assembler accepts the command,
since even with a recent CPU the toolchain could be old.
Patch by Manabu Ori, significantly modified by me.
All supported platforms support the C89 standard function atexit()
(SunOS 4 probably being the last one not to), and supporting both
makes the code clumsy.
