In 83ff1618 we defined integer limits iff they're not provided by the
system. That turns out not to be the greatest idea because there's
different ways some datatypes can be represented. E.g. on OSX PG's 64bit
datatype will be a 'long int', but OSX unconditionally uses 'long
long'. That disparity then can lead to warnings, e.g. around printf
formats.

One way to fix that would be to back int64 using stdint.h's
int64_t. While a good idea it's not that easy to implement. We would
e.g. need to include stdint.h in our external headers, which we don't
today. Also computing the correct int64 printf formats in that case is
nontrivial.

Instead simply prefix the integer limits with PG_ and define them
unconditionally. I've adjusted all the references to them in code, but
not the ones in comments; the latter seems unnecessary to me.

Discussion: 20150331141423.GK4878@alap3.anarazel.de

inet, cidr, and timetz indexes still cannot support index-only scans,
because they don't store the original unmodified value in the index, but a
derived approximate value.

The gbt_var_key_copy function was doing two different things depending on
the boolean argument. Seems cleaner to have two separate functions.

Remove unused argument from gbt_num_compress.

Several submitted and even committed patches have run into the problem
that C89, our baseline, does not provide minimum/maximum values for
various integer datatypes. C99's stdint.h does, but we can't rely on
it.

Several parts of the code defined limits locally, so instead centralize
the definitions to c.h.

This patch also changes the more obvious usages of literal limit values;
there's more places that could be changed, but it's less clear whether
it's beneficial to change those.

Author: Andrew Gierth
Discussion: 87619tc5wc.fsf@news-spur.riddles.org.uk

Up to now, PG has assumed that any given timezone abbreviation (such as
"EDT") represents a constant GMT offset in the usage of any particular
region; we had a way to configure what that offset was, but not for it
to be changeable over time.  But, as with most things horological, this
view of the world is too simplistic: there are numerous regions that have
at one time or another switched to a different GMT offset but kept using
the same timezone abbreviation.  Almost the entire Russian Federation did
that a few years ago, and later this month they're going to do it again.
And there are similar examples all over the world.

To cope with this, invent the notion of a "dynamic timezone abbreviation",
which is one that is referenced to a particular underlying timezone
(as defined in the IANA timezone database) and means whatever it currently
means in that zone.  For zones that use or have used daylight-savings time,
the standard and DST abbreviations continue to have the property that you
can specify standard or DST time and get that time offset whether or not
DST was theoretically in effect at the time.  However, the abbreviations
mean what they meant at the time in question (or most recently before that
time) rather than being absolutely fixed.

The standard abbreviation-list files have been changed to use this behavior
for abbreviations that have actually varied in meaning since 1970.  The
old simple-numeric definitions are kept for abbreviations that have not
changed, since they are a bit faster to resolve.

While this is clearly a new feature, it seems necessary to back-patch it
into all active branches, because otherwise use of Russian zone
abbreviations is going to become even more problematic than it already was.
This change supersedes the changes in commit 513d06de et al to modify the
fixed meanings of the Russian abbreviations; since we've not shipped that
yet, this will avoid an undesirably incompatible (not to mention incorrect)
change in behavior for timestamps between 2011 and 2014.

This patch makes some cosmetic changes in ecpglib to keep its usage of
datetime lookup tables as similar as possible to the backend code, but
doesn't do anything about the increasingly obsolete set of timezone
abbreviation definitions that are hard-wired into ecpglib.  Whatever we
do about that will likely not be appropriate material for back-patching.
Also, a potential free() of a garbage pointer after an out-of-memory
failure in ecpglib has been fixed.

This patch also fixes pre-existing bugs in DetermineTimeZoneOffset() that
caused it to produce unexpected results near a timezone transition, if
both the "before" and "after" states are marked as standard time.  We'd
only ever thought about or tested transitions between standard and DST
time, but that's not what's happening when a zone simply redefines their
base GMT offset.

In passing, update the SGML documentation to refer to the Olson/zoneinfo/
zic timezone database as the "IANA" database, since it's now being
maintained under the auspices of IANA.

The macaddr opclass stores two macaddr structs (each of size 6) in an
index column that's declared as being of type gbtreekey16, ie 16 bytes.
In the original coding this led to passing a palloc'd value of size 12
to the index insertion code, so that data would be fetched past the
end of the allocated value during index tuple construction.  This makes
valgrind unhappy.  In principle it could result in a SIGSEGV, though
with the current implementation of palloc there's no risk since
the 12-byte request size would be rounded up to 16 bytes anyway.

To fix, add a field to struct gbtree_ninfo showing the declared size of
the index datums, and use that in the palloc requests; and use palloc0
to be sure that any wasted bytes are cleanly initialized.

Per report from Andres Freund.  No back-patch since there's no current
risk of a real problem.

Because of gcc -Wmissing-prototypes, all functions in dynamically
loadable modules must have a separate prototype declaration.  This is
meant to detect global functions that are not declared in header files,
but in cases where the function is called via dfmgr, this is redundant.
Besides filling up space with boilerplate, this is a frequent source of
compiler warnings in extension modules.

We can fix that by creating the function prototype as part of the
PG_FUNCTION_INFO_V1 macro, which such modules have to use anyway.  That
makes the code of modules cleaner, because there is one less place where
the entry points have to be listed, and creates an additional check that
functions have the right prototype.

Remove now redundant prototypes from contrib and other modules.

This is the first run of the Perl-based pgindent script.  Also update
pgindent instructions.

This addresses only those cases that are easy to fix by adding or
moving a const qualifier or removing an unnecessary cast.  There are
many more complicated cases remaining.

remove from local *.h files.

Per suggestion from Alvaro.

This extends GiST's support for nearest-neighbor searches to many of the
standard data types.

Teodor Sigaev

optimization, so don't backpatch.

provided by Andrew.

This particular batch was just for *.c and *.h file.

The changes were made with the following 2 commands:

find . \( \( -name 'libstemmer' -o -name 'expected' -o -name 'ppport.h' \) -prune \) -o  \( -name '*.[ch]'  \) \( -exec grep -q '\$PostgreSQL' {} \; -o -print \) | while read file ; do head -n 1 < $file | grep -q '^/\*' && echo $file; done | xargs -l sed -i -e '1s/^\// /' -e '1i/*\n * $PostgreSQL:$ \n *'

find . \( \( -name 'libstemmer' -o -name 'expected' -o -name 'ppport.h' \) -prune \) -o  \( -name '*.[ch]'  \) \( -exec grep -q '\$PostgreSQL' {} \; -o -print \) | xargs -l sed -i -e '1i/*\n * $PostgreSQL:$ \n */'

where Datum is 8 bytes wide.  Since this will break old-style C functions
(those still using version 0 calling convention) that have arguments or
results of these types, provide a configure option to disable it and retain
the old pass-by-reference behavior.  Likewise, provide a configure option
to disable the recently-committed float4 pass-by-value change.

Zoltan Boszormenyi, plus configurability stuff by me.

"consistent" functions, and remove pg_amop.opreqcheck, as per recent
discussion.  The main immediate benefit of this is that we no longer need
8.3's ugly hack of requiring @@@ rather than @@ to test weight-using tsquery
searches on GIN indexes.  In future it should be possible to optimize some
other queries better than is done now, by detecting at runtime whether the
index match is exact or not.

Tom Lane, after an idea of Heikki's, and with some help from Teodor.

* new split algorithm (as proposed in http://archives.postgresql.org/pgsql-hackers/2006-06/msg00254.php)
  * possible call pickSplit() for second and below columns
  * add spl_(l|r)datum_exists to GIST_SPLITVEC -
    pickSplit should check its values to use already defined
    spl_(l|r)datum for splitting. pickSplit should set
    spl_(l|r)datum_exists to 'false' (if they was 'true') to
    signal to caller about using spl_(l|r)datum.
  * support for old pickSplit(): not very optimal
    but correct split
* remove 'bytes' field from GISTENTRY: in any case size of
  value is defined by it's type.
* split GIST_SPLITVEC to two structures: one for using in picksplit
  and second - for internal use.
* some code refactoring
* support of subsplit to rtree opclasses

TODO: add support of subsplit to contrib modules

like '23:59:60' because of fractional-second roundoff problems.  Trying
to control this upstream of the actual display code was hopeless; the right
way is to explicitly round fractional seconds in the display code and then
refigure the results if the fraction rounds up to 1.  Per bug #1927.

- Fix wrong index results on text, char, varchar for multibyte strings
- Fix some SIGFPE signals
- Add support for infinite timestamps
- Because of locale settings, btree_gist can not be a prefix index anymore (for text).
  Each node holds now just the lower and upper boundary.

current time: provide a GetCurrentTimestamp() function that returns
current time in the form of a TimestampTz, instead of separate time_t
and microseconds fields.  This is what all the callers really want
anyway, and it eliminates low-level dependencies on AbsoluteTime,
which is a deprecated datatype that will have to disappear eventually.

methods in a short-lived memory context, there is no need for GiST methods
to do their own manual (and error-prone) memory management.

- Add aligment for interval data types
- Avoid floating point overflow in penalty functions
Janko Richter <jankorichter@yahoo.de> and teodor

New version. Add support for int2, int8, float4, float8, timestamp with/without time zone, time with/without time zone, date, interval, oid, money and macaddr, char, varchar/text, bytea, numeric, bit, varbit, inet/cidr types for GiST

boxes. Change interface to user-defined GiST support methods union and
picksplit. Now instead of bytea struct it used special GistEntryVector
structure.

(7.3 and current CVS) with support of int8, float4, float8
in addition to int4. Thanks Janko Richter for contribution.

Oleg Bartunov