Older versions of GCC appear to report these with the current standard
option set, newer versions need -Wformat-security.

This way errors from fetching tuples are correctly reported as errors
in the SPI call.  While at it, avoid palloc(0).

Jan Urbański

Instead of checking whether the arglist is NULL and then if its length
is 0, do it in one step, and outside of the try/catch block.

Jan Urbański

This reverts commit 740e54ca, which seems
to have tickled an optimization bug in gcc 4.5.x, as reported upstream at
https://bugzilla.redhat.com/show_bug.cgi?id=671899
Since this patch had no purpose beyond code beautification, it's not
worth expending a lot of effort to look for another workaround.

Global error handling led to confusion and was hard to manage.  With
this change, errors from PostgreSQL are immediately reported to Python
as exceptions.  This requires setting a Python exception after
reporting the caught PostgreSQL error as a warning, because PLy_elog
destroys the Python exception state.

Ideally, all places where PostgreSQL errors need to be reported back
to Python should be wrapped in subtransactions, to make going back to
Python from a longjmp safe.  This will be handled in a separate patch.

Jan Urbański

The way the exception types where added to the module was wrong for
Python 3.  Exception classes were not actually available from plpy.
Fix that by factoring out code that is responsible for defining new
Python exceptions and make it work with Python 3.  New regression test
makes sure the plpy module has the expected contents.

Jan Urbanśki, slightly revised by me

Hitoshi Harada

Hitoshi Harada

This makes PLy_procedure_create a bit more manageable.

Jan Urbański

Jan Urbański, reviewed by Peter Eisentraut, Álvaro Herrera, Tom Lane :-)

Jan Urbański

The previous code would try to print out a null pointer.

Jan Urbański

The latter is undocumented and the speed gain is negligible.

Jan Urbański

Pay attention to the attisdropped field and skip over TupleDesc fields
that have it set.  Not a real problem until we get table returning
functions, but it's the right thing to do anyway.

Jan Urbański

As discussed, even if the PL needs a permanent memory location, it
should use palloc, not malloc.  It also makes error handling easier.

Jan Urbański

If the function using yield to return rows fails halfway, the iterator
stays open and subsequent calls to the function will resume reading
from it.  The fix is to unref the iterator and set it to NULL if there
has been an error.

Jan Urbański

Two separate hash tables are used for regular procedures and for
trigger procedures, since the way trigger procedures work is quite
different from normal stored procedures.  Change the signatures of
PLy_procedure_{get,create} to accept the function OID and a Boolean
flag indicating whether it's a trigger.  This should make implementing
a PL/Python validator easier.

Using HTABs instead of Python dictionaries makes error recovery
easier, and allows for procedures to be cached based on their OIDs,
not their names.  It also allows getting rid of the PyCObject field
that used to hold a pointer to PLyProcedure, since PyCObjects are
deprecated in Python 2.7 and replaced by Capsules in Python 3.

Jan Urbański

Per bug #5835 by Julien Demoor
Author: Alex Hunsaker

We must stay in the function's SPI context until done calling the iterator
that returns the set result.  Otherwise, any attempt to invoke SPI features
in the python code called by the iterator will malfunction.  Diagnosis and
patch by Jan Urbanski, per bug report from Jean-Baptiste Quenot.

Back-patch to 8.2; there was no support for SRFs in previous versions of
plpython.

This was broken in 9.0 while improving plpython's conversion behavior for
bytea and boolean.  Per bug report from maizi.

This patch adds the SQL-standard concept of an INSTEAD OF trigger, which
is fired instead of performing a physical insert/update/delete.  The
trigger function is passed the entire old and/or new rows of the view,
and must figure out what to do to the underlying tables to implement
the update.  So this feature can be used to implement updatable views
using trigger programming style rather than rule hacking.

In passing, this patch corrects the names of some columns in the
information_schema.triggers view.  It seems the SQL committee renamed
them somewhere between SQL:99 and SQL:2003.

Dean Rasheed, reviewed by Bernd Helmle; some additional hacking by me.

Various places were testing TRIGGER_FIRED_BEFORE() where what they really
meant was !TRIGGER_FIRED_AFTER(), or vice versa.  This needs to be cleaned
up because there are about to be more than two possible states.

We might want to note this in the 9.1 release notes as something for
trigger authors to double-check.

For consistency's sake I also changed some places that assumed that
TRIGGER_FIRED_FOR_ROW and TRIGGER_FIRED_FOR_STATEMENT are necessarily
mutually exclusive; that's not in immediate danger of breaking, but
it's still sloppier than it should be.

Extracted from Dean Rasheed's patch for triggers on views.  I'm committing
this separately since it's an identifiable separate issue, and is the
only reason for the patch to touch most of these particular files.

This is reproducibly possible in Python 2.7 if the user turned
PendingDeprecationWarning into an error, but it's theoretically also possible
in earlier versions in case of exceptional conditions.

backpatched to 8.0

(_PG_init should be called only once anyway, but as long as it's got an
internal guard against repeat calls, that should be in front of the
version check.)

pg_pltemplate

This should have a catversion bump, but it's still being debated whether
it's worth it during beta.

conversion.  Per bug #5497 from David Gardner.

Per report from Andres Freund.

memory if the result had zero rows, and also if there was any sort of error
while converting the result tuples into Python data.  Reported and partially
fixed by Andres Freund.

Back-patch to all supported versions.  Note: I haven't tested the 7.4 fix.
7.4's configure check for python is so obsolete it doesn't work on my
current machines :-(.  The logic change is pretty straightforward though.

with a few strategically placed pg_verifymbstr calls.

In PLy_spi_execute_plan, use the data-type specific Python-to-PostgreSQL
conversion function instead of passing everything through InputFunctionCall
as a string.  The equivalent fix was already done months ago for function
parameters and return values, but this other gateway between Python and
PostgreSQL was apparently forgotten.  As a result, data types that need
special treatment, such as bytea, would misbehave when used with
plpy.execute.

old memory context in plpython.  Before only one of them was marked
volatile, but per report from Zdenek Kotala, some compilers do the
wrong thing here.

The purpose of this change is to eliminate the need for every caller
of SearchSysCache, SearchSysCacheCopy, SearchSysCacheExists,
GetSysCacheOid, and SearchSysCacheList to know the maximum number
of allowable keys for a syscache entry (currently 4).  This will
make it far easier to increase the maximum number of keys in a
future release should we choose to do so, and it makes the code
shorter, too.

Design and review by Tom Lane.

Also cleaned up some redundancies between the primary error messages and the
error context in PL/Python.

Hannu Valtonen

Mimic the Python interpreter's own logic for printing exceptions instead
of just using the straight str() call, so that
you get

    plpy.SPIError

instead of

    <class 'plpy.SPIError'>

and for built-in exceptions merely

    UnicodeEncodeError

Besides looking better this cuts down on the endless version differences
in the regression test expected files.

Behaves more or less unchanged compared to Python 2, but the new language
variant is called plpython3u.  Documentation describing the naming scheme
is included.

Support arrays as parameters and return values of PL/Python functions.