change saves a great deal of space in pg_proc and its primary index,
and it eliminates the former requirement that INDEX_MAX_KEYS and
FUNC_MAX_ARGS have the same value. INDEX_MAX_KEYS is still embedded
in the on-disk representation (because it affects index tuple header
size), but FUNC_MAX_ARGS is not. I believe it would now be possible
to increase FUNC_MAX_ARGS at little cost, but haven't experimented yet.
There are still a lot of vestigial references to FUNC_MAX_ARGS, which
I will clean up in a separate pass. However, getting rid of it
altogether would require changing the FunctionCallInfoData struct,
and I'm not sure I want to buy into that.
Document use of macros for pg_printf functions.
Bump major versions of all interfaces to handle movement of get_progname
from libpq to libpgport in 8.0, and probably other libpgport changes in 8.1.
and parsing work in PL/PgSQL:
- memory management is now done via palloc(). The compiled representation
of each function now has its own memory context. Therefore, the storage
consumed by a function can be reclaimed via MemoryContextDelete().
During compilation, the CurrentMemoryContext is the function's memory
context. This means that a palloc() is sufficient to allocate memory
that will have the same lifetime as the function itself. As a result,
code invoked during compilation should be careful to pfree() temporary
allocations to avoid leaking memory. Since a lot of the code in the
backend is not careful about releasing palloc'ed memory, that means
we should switch into a temporary memory context before invoking
backend functions. A temporary context appropriate for such allocations
is `compile_tmp_cxt'.
- The ability to use palloc() allows us to simply a lot of the code in
the parser. Rather than representing lists of elements via ad hoc
linked lists or arrays, we can use the List type. Rather than doing
malloc followed by memset(0), we can just use palloc0().
- We now check that the user has supplied the right number of parameters
to a RAISE statement. Supplying either too few or too many results in
an error (at runtime).
- PL/PgSQL's parser needs to accept arbitrary SQL statements. Since we
do not want to duplicate the SQL grammar in the PL/PgSQL grammar, this
means we need to be quite lax in what the PL/PgSQL grammar considers
a "SQL statement". This can lead to misleading behavior if there is a
syntax error in the function definition, since we assume a malformed
PL/PgSQL construct is a SQL statement. Furthermore, these errors were
only detected at runtime (when we tried to execute the alleged "SQL
statement" via SPI).
To rectify this, the patch changes the parser to invoke the main SQL
parser when it sees a string it believes to be a SQL expression. This
means that synctically-invalid SQL will be rejected during the
compilation of the PL/PgSQL function. This is only done when compiling
for "validation" purposes (i.e. at CREATE FUNCTION time), so it should
not impose a runtime overhead.
- Fixes for the various buffer overruns I've patched in stable branches
in the past few weeks. I've rewritten code where I thought it was
warranted (unlike the patches applied to older branches, which were
minimally invasive).
- Various other minor changes and cleanups.
- Updates to the regression tests.
initially NULL. For 8.0 we changed the main executor to have this
behavior in an UPDATE of an array column, but plpgsql's equivalent case
was overlooked. Per report from Sven Willenberger.
MemoryContextAllocZero back to MemoryContextAlloc, same as it was in 7.4.
The zeroing is unnecessary since all the meaningful fields are filled in
just below. I had made it do that out of neatnik-ism, but some testing
with an example provided by Pavel Stehule showed that the zeroing was
accounting for about 5% of the runtime in a compute-intensive plpgsql
function. That seems a bit high of a price for neatnik-ism...
advancing ActiveSnapshot when we are inside a volatile function.
Per example from Gaetano Mendola. Add a regression test to catch
similar problems in future.
several reports of users being confused when they attempt to use ELSEIF
and run into trouble due to PL/PgSQL's lax parser. The parser will be
improved for 8.1, but we can fix most of the problem by allowing ELSEIF
for now.
of an inheritance child table is binary-compatible with the rowtype of
its parent, invent an expression node type that does the conversion
correctly. Fixes the new bug exhibited by Kris Shannon as well as a
lot of old bugs that would only show up when using multiple inheritance
or after altering the parent table.
data returned from Perl. Consolidate multiple bits of code to convert
a Perl hash to a tuple, and drive the conversion off the keys present
in the hash rather than the tuple column names, so we detect error if
the hash contains keys it shouldn't. (This means keys not in the hash
will silently default to NULL, which seems ok to me.) Fix a bunch of
reference-count leaks too.
subtransactions quite right either: the ReleaseCurrentSubTransaction
call should occur inside the PG_TRY, so that the proper path is taken
if an error occurs during subtransaction commit. This assumes that
AbortSubTransaction can cope with the state left behind if
CommitSubTransaction fails partway through, but we were already
requiring that.
operations are now run as subtransactions, so that errors in them
can be reported as ordinary Perl or Tcl errors and caught by the
normal error handling convention of those languages. Also do some
minor code cleanup in pltcl.c: extract a large chunk of duplicated
code in pltcl_SPI_execute and pltcl_SPI_execute_plan into a shared
subroutine.
rather than longjmp'ing clear out of Perl and thereby leaving Perl in
a broken state. Also some minor prettification of error messages.
Still need to do something with spi_exec_query() error handling.
for the languages even when not installed in a standard directory.
pltcl may need this treatment as well, but we don't have the right path
conveniently available, so I'll leave it alone as long as there aren't
actual reports of trouble.
may expand the Perl stack, therefore we must SPAGAIN to reload the local
stack pointer after calling it. Also a couple other marginal readability
improvements.
some of the bugs exposed thereby. The remaining 'might be used uninitialized'
warnings look like live bugs, but I am not familiar enough with Perl/C hacking
to tell how to fix them.
We don't really want to start a new SPI connection, just keep using the old
one; otherwise we have memory management problems as illustrated by
John Kennedy's bug report of today. This requires a bit of a hack to
ensure the SPI stack state is properly restored, but then again what we
were doing before was a hack too, strictly speaking. Add a regression
test to cover this case.
1. Two minor cleanups:
- We don't need to call hv_exists+hv_fetch; we should just check the
return value of hv_fetch.
- newSVpv("undef",0) is the string "undef", not a real undef.
2. This should fix the bug Andrew Dunstan described in a recent -hackers
post. It replaces three bogus "eval_pv(key, 0)" calls with newSVpv,
and eliminates another redundant hv_exists+hv_fetch pair.
3. plperl_build_tuple_argument builds up a string of Perl code to create
a hash representing the tuple. This patch creates the hash directly.
4. Another minor cleanup: replace a couple of av_store()s with av_push.
5. Analogous to #3 for plperl_trigger_build_args. This patch removes the
static sv_add_tuple_value function, which does much the same as two
other utility functions defined later, and merges the functionality
into plperl_hash_from_tuple.
I have tested the patches to the best of my limited ability, but I would
appreciate it very much if someone else could review and test them too.
(Thanks to Andrew and David Fetter for their help with some testing.)
Abhijit Menon-Sen
argument, leading to label matching failures at run-time. Per report from
Patrick Fiche. Also, fix it so that an unrecognized label argument draws
a more useful error message than 'syntax error'.
-L spec rather than assuming libpython is in the standard search path
(this returns to the way 7.4 did it). But check the distutils output
to see if it looks like Python has built a shared library, and if so
link with that instead of the probably-not-shared library found in
configdir.
- replace some function signatures of the form "some_type foo()" with
"some_type foo(void)"
- replace a few instances of a literal 0 being used as a NULL pointer;
there are more instances of this in the code, but I just fixed a few
- in src/backend/utils/mb/wstrncmp.c, replace K&R style function
declarations with ANSI style, remove use of 'register' keyword
- remove an "extern" modifier that was applied to a function definition
(rather than a declaration)
to unreserved keyword, use ereport not elog, assign a separate error code
for 'could not obtain lock' so that applications will be able to detect
that case cleanly.
