Subject: [HACKERS] Small date patches (resubmitted)
Here a some small patches for the date/time code. They set the default
output format for the datetime type to the traditional Postgres
style, and fix a date debugging declaration. I submitted these
a couple of days ago, but they might have gotten lost...
NOTE: the second patch to dt.c is what I believe D'Arcy submitted as well,
that I claimed was taken out...sorry D'Arcy, my fault :(
Subject: Re: [HACKERS] abstime "now" broken
Yes, I broke 'now' :( with an attempt at a bug fix involving
servers running in the UTC/GMT timezone. These patches fix
the problem, and have been tested in GMT (+00 hours),
PST (-08), and NZT (+12) timezones which exercized the code for
various cases including across day boundaries. btw, this code
fixes the same type of problem for 'today', 'yesterday', 'tomorrow',
for DATETIME, ABSTIME, DATE and TIME types.
The bugfix itself is quite small, but I have accumulated other
changes in the datetime data type and include them here also.
One set of changes involves printing ISO-formatted dates and
is in response to the helpful information from Kurt Lidl regarding
ANSI SQL dates. I'll send another e-mail sometime soon discussing
more issues he has raised...
Subject: [HACKERS] backend/utils/adt/timestamp.c
Back to this timezone stuff. The struct tm has a field (tm_gmtoff) which
is the offset from UTC (GMT is archaic BTW) in seconds. Is this the
value you are looking for when you use timezone? Note that this applies
to NetBSD but it does not appear to be in either ANSI C or POSIX. This
looks like one of those things that is just going to have to be hand
coded for each platform.
Why not just store the values in UTC and use localtime instead of
gmtime when retrieving the value?
Also, you assume the time is returned as a 4 byte integer. In fact,
there is not even any requirement that time be an integral value. You
should use time_t here.
The input function seems unduly restrictive. Somewhere in the sources
there is an input function that allows words for months. Can't we do
the same here?
There is a standard function, difftime, for subtracting two times. It
deals with cases where time_t is not integral. There is, however, a
small performance hit since it returns a double and I don't believe
there is any system currently which uses anything but an integral for
time_t. Still, this is technically the correct and portable thing to do.
The returns from the various comparisons should probably be a bool.
Subject: [HACKERS] More patches for date/time
I have accumulated several patches to add functionality to the datetime
and timespan data types as well as to fix reported porting bugs on non-BSD
machines. These patches are:
dt.c.patch - add datetime_part(), fix bugs
dt.h.patch - add quarter and timezone support, add prototypes
globals.c.patch - add time and timezone variables
miscadmin.h.patch - add time and timezone variables
nabstime.c.patch - add datetime conversion routine
nabstime.h.patch - add prototypes
pg_operator.h.patch - add datetime operators, clean up formatting
pg_proc.h.patch - add datetime functions, reassign conflicting date OIDs
pg_type.h.patch - add datetime and timespan data types
The dt.c and pg_proc.h patches are fairly large; the latter mostly because I tried
to get some columns for existing entries to line up.
Subject: [HACKERS] backend/utils/adt/nabstime.c
There is a problem with some of the calls to strftime. The second arg is
missing. In all cases the buffer is CTZName which, according to the
file init/globals.c, is char CTZName[8] so I have added this value.
I know there should be a #define set up for this but I wasn't sure
which header to put it in.
Subject: [HACKERS] Patches for 970316 compilation
I made a small pre-emptive change in the new datetime code to eliminate
calls to infnan(). Hopefully this will make Solaris (and probably other
non-GNUlib) systems happier. Didn't find fe-connect.h in the 970316
distribution, so made one up. Also, one of the test routines needs an
update for the geo-decls.h -> geo_decls.h name change.
Patches appear below...
Subject: [HACKERS] linux/alpha patches
These patches lay the groundwork for a Linux/Alpha port. The port doesn't
actually work unless you tweak the linker to put all the pointers in the
first 32 bits of the address space, but it's at least a start. It
implements the test-and-set instruction in Alpha assembly, and also fixes
a lot of pointer-to-integer conversions, which is probably good anyway.
gmake of the code without interruption.
There's also some tidy-up of the MAXPATHLEN stuff based on the assumption that
all supported platforms have MAXPATHLEN defined in <sys/param.h>.
(The only unknowns for the above are AIX and IRIX5.)
cc1: warnings being treated as errors
datum.c: In function `DatumGetSize':
datum.c:57: warning: unsigned value >= 0 is always 1
gmake[3]: *** [datum.o] Error 1
There was:
if (byVal) {
if (len >= 0 && len <= sizeof(Datum)) {
but len has type Size (unsigned int) and so now there is:
if (byVal) {
if (len <= sizeof(Datum)) {
When an acl item is added or updated the new entry is deleted if it has no
permissions and the acl array is shrinked. This is is done by decrementing
the number of items without updating the corresponding array size.
The array with the incorrect size is later read by pg_aclcheck and the entry
count is used to allocate a new array while the array size is used to copy
the old one. This causes a memory corruption and a backend crash.
This happens only to normal user as the administrator bypasses acl checks.
Massimo Dal Zotto
* Wrote max(date) and min(date) aggregates
* Wrote operator "-" for date; date - date yields number of days
difference
* Wrote operator+(date,int) and operator-(date,int); the int is the
number of days. Each operator returns a new date.
By: Tom Tromey <tromey@creche.cygnus.com>
