summaryrefslogtreecommitdiff
path: root/src/backend/utils
AgeCommit message (Collapse)Author
2011-06-17Add overflow checks to int4 and int8 versions of generate_series().Robert Haas
The previous code went into an infinite loop after overflow. In fact, an overflow is not really an error; it just means that the current value is the last one we need to return. So, just arrange to stop immediately when overflow is detected. Back-patch all the way.
2011-06-15Fix failure to account for memory used by tuplestore_putvalues().Tom Lane
This oversight could result in a tuplestore using much more than the intended amount of memory. It would only happen in a code path that loaded a tuplestore via tuplestore_putvalues(), and many of those won't emit huge amounts of data; but cases such as holdable cursors and plpgsql's RETURN NEXT command could have the problem. The fix ensures that the tuplestore will switch to write-to-disk mode when it overruns work_mem. The potential overrun was finite, because we would still count the space used by the tuple pointer array, so the tuplestore code would eventually flip into write-to-disk mode anyway. When storing wide tuples we would go far past the expected work_mem usage before that happened; but this may account for the lack of prior reports. Back-patch to 8.4, where tuplestore_putvalues was introduced. Per bug #6061 from Yann Delorme.
2011-05-28Fix null-dereference crash in parse_xml_decl().Tom Lane
parse_xml_decl's header comment says you can pass NULL for any unwanted output parameter, but it failed to honor this contract for the "standalone" flag. The only currently-affected caller is xml_recv, so the net effect is that sending a binary XML value containing a standalone parameter in its xml declaration would crash the backend. Per bug #6044 from Christopher Dillard. In passing, remove useless initializations of parse_xml_decl's output parameters in xml_parse. Back-patch to 8.3, where this code was introduced.
2011-05-26Make decompilation of optimized CASE constructs more robust.Tom Lane
We had some hacks in ruleutils.c to cope with various odd transformations that the optimizer could do on a CASE foo WHEN "CaseTestExpr = RHS" clause. However, the fundamental impossibility of covering all cases was exposed by Heikki, who pointed out that the "=" operator could get replaced by an inlined SQL function, which could contain nearly anything at all. So give up on the hacks and just print the expression as-is if we fail to recognize it as "CaseTestExpr = RHS". (We must cover that case so that decompiled rules print correctly; but we are not under any obligation to make EXPLAIN output be 100% valid SQL in all cases, and already could not do so in some other cases.) This approach requires that we have some printable representation of the CaseTestExpr node type; I used "CASE_TEST_EXPR". Back-patch to all supported branches, since the problem case fails in all.
2011-05-24Avoid uninitialized bits in the result of QTN2QT().Tom Lane
Found with additional valgrind testing. Noah Misch
2011-04-29Remove special case for xmin == xmax in HeapTupleSatisfiesVacuum().Tom Lane
VACUUM was willing to remove a committed-dead tuple immediately if it was deleted by the same transaction that inserted it. The idea is that such a tuple could never have been visible to any other transaction, so we don't need to keep it around to satisfy MVCC snapshots. However, there was already an exception for tuples that are part of an update chain, and this exception created a problem: we might remove TOAST tuples (which are never part of an update chain) while their parent tuple stayed around (if it was part of an update chain). This didn't pose a problem for most things, since the parent tuple is indeed dead: no snapshot will ever consider it visible. But MVCC-safe CLUSTER had a problem, since it will try to copy RECENTLY_DEAD tuples to the new table. It then has to copy their TOAST data too, and would fail if VACUUM had already removed the toast tuples. Easiest fix is to get rid of the special case for xmin == xmax. This may delay reclaiming dead space for a little bit in some cases, but it's by far the most reliable way to fix the issue. Per bug #5998 from Mark Reid. Back-patch to 8.3, which is the oldest version with MVCC-safe CLUSTER.
2011-04-29Rewrite pg_size_pretty() to avoid compiler bug.Tom Lane
Convert it to use successive shifts right instead of increasing a divisor. This is probably a tad more efficient than the original coding, and it's nicer-looking than the previous patch because we don't need a special case to avoid overflow in the last branch. But the real reason to do it is to avoid a Solaris compiler bug, as per results from buildfarm member moa.
2011-04-27Fix array- and path-creating functions to ensure padding bytes are zeroes.Tom Lane
Per recent discussion, it's important for all computed datums (not only the results of input functions) to not contain any ill-defined (uninitialized) bits. Failing to ensure that can result in equal() reporting that semantically indistinguishable Consts are not equal, which in turn leads to bizarre and undesirable planner behavior, such as in a recent example from David Johnston. We might eventually try to fix this in a general manner by allowing datatypes to define identity-testing functions, but for now the path of least resistance is to expect datatypes to force all unused bits into consistent states. Per some testing by Noah Misch, array and path functions seem to be the only ones presenting risks at the moment, so I looked through all the functions in adt/array*.c and geo_ops.c and fixed them as necessary. In the array functions, the easiest/safest fix is to allocate result arrays with palloc0 instead of palloc. Possibly in future someone will want to look into whether we can just zero the padding bytes, but that looks too complex for a back-patchable fix. In the path functions, we already had a precedent in path_in for just zeroing the one known pad field, so duplicate that code as needed. Back-patch to all supported branches.
2011-04-25Fix pg_size_pretty() to avoid overflow for inputs close to INT64_MAX.Tom Lane
The expression that tried to round the value to the nearest TB could overflow, leading to bogus output as reported in bug #5993 from Nicola Cossu. This isn't likely to ever happen in the intended usage of the function (if it could, we'd be needing to use a wider datatype instead); but it's not hard to give the expected output, so let's do so.
2011-04-12Be more wary of missing statistics in eqjoinsel_semi().Tom Lane
In particular, if we don't have real ndistinct estimates for both sides, fall back to assuming that half of the left-hand rows have join partners. This is what was done in 8.2 and 8.3 (cf nulltestsel() in those versions). It's pretty stupid but it won't lead us to think that an antijoin produces no rows out, as seen in recent example from Uwe Schroeder.
2011-04-01Avoid palloc before CurrentMemoryContext is set up on win32Magnus Hagander
Instead, write the unconverted output - it will be in the wrong encoding, but at least we don't crash. Rushabh Lathia
2011-03-22Avoid potential deadlock in InitCatCachePhase2().Tom Lane
Opening a catcache's index could require reading from that cache's own catalog, which of course would acquire AccessShareLock on the catalog. So the original coding here risks locking index before heap, which could deadlock against another backend trying to get exclusive locks in the normal order. Because InitCatCachePhase2 is only called when a backend has to start up without a relcache init file, the deadlock was seldom seen in the field. (And by the same token, there's no need to worry about any performance disadvantage; so not much point in trying to distinguish exactly which catalogs have the risk.) Bug report, diagnosis, and patch by Nikhil Sontakke. Additional commentary by me. Back-patch to all supported branches.
2011-03-11On further reflection, we'd better do the same in int.c.Tom Lane
We previously heard of the same problem in int24div(), so there's not a good reason to suppose the problem is confined to cases involving int8.
2011-03-11Put in some more safeguards against executing a division-by-zero.Tom Lane
Add dummy returns before every potential division-by-zero in int8.c, because apparently further "improvements" in gcc's optimizer have enabled it to break functions that weren't broken before. Aurelien Jarno, via Martin Pitt
2011-02-16Fix bogus test for hypothetical indexes in get_actual_variable_range().Tom Lane
That function was supposing that indexoid == 0 for a hypothetical index, but that is not likely to be true in any non-toy implementation of an index adviser, since assigning a fake OID is the only way to know at EXPLAIN time which hypothetical index got selected. Fix by adding a flag to IndexOptInfo to mark hypothetical indexes. Back-patch to 9.0 where get_actual_variable_range() was added. Gurjeet Singh
2011-02-01Fix wrong error reports in 'number of array dimensions exceeds theItagaki Takahiro
maximum allowed' messages, that have reported one-less dimensions. Alexey Klyukin
2011-01-17Fix miscalculation of itemsafter in array_set_slice().Tom Lane
If the slice to be assigned to was before the existing array lower bound (requiring at least one null element to spring into existence to fill the gap), the code miscalculated how many entries needed to be copied from the old array's null bitmap. This could result in trashing the array's data area (as seen in bug #5840 from Karsten Loesing), or worse. This has been broken since we first allowed the behavior of assigning to non-adjacent slices, in 8.2. Back-patch to all affected versions.
2010-12-28Avoid unexpected conversion overflow in planner for distant date values.Tom Lane
The "date" type supports a wider range of dates than int64 timestamps do. However, there is pre-int64-timestamp code in the planner that assumes that all date values can be converted to timestamp with impunity. Fortunately, what we really need out of the conversion is always a double (float8) value; so even when the date is out of timestamp's range it's possible to produce a sane answer. All we need is a code path that doesn't try to force the result into int64. Per trouble report from David Rericha. Back-patch to all supported versions. Although this is surely a corner case, there's not much point in advertising a date range wider than timestamp's if we will choke on such values in unexpected places.
2010-12-19Fix up handling of simple-form CASE with constant test expression.Tom Lane
eval_const_expressions() can replace CaseTestExprs with constants when the surrounding CASE's test expression is a constant. This confuses ruleutils.c's heuristic for deparsing simple-form CASEs, leading to Assert failures or "unexpected CASE WHEN clause" errors. I had put in a hack solution for that years ago (see commit 514ce7a331c5bea8e55b106d624e55732a002295 of 2006-10-01), but bug #5794 from Peter Speck shows that that solution failed to cover all cases. Fortunately, there's a much better way, which came to me upon reflecting that Peter's "CASE TRUE WHEN" seemed pretty redundant: we can "simplify" the simple-form CASE to the general form of CASE, by simply omitting the constant test expression from the rebuilt CASE construct. This is intuitively valid because there is no need for the executor to evaluate the test expression at runtime; it will never be referenced, because any CaseTestExprs that would have referenced it are now replaced by constants. This won't save a whole lot of cycles, since evaluating a Const is pretty cheap, but a cycle saved is a cycle earned. In any case it beats kluging ruleutils.c still further. So this patch improves const-simplification and reverts the previous change in ruleutils.c. Back-patch to all supported branches. The bug exists in 8.1 too, but it's out of warranty.
2010-12-19Fix erroneous parsing of tsquery input "... & !(subexpression) | ..."Tom Lane
After parsing a parenthesized subexpression, we must pop all pending ANDs and NOTs off the stack, just like the case for a simple operand. Per bug #5793. Also fix clones of this routine in contrib/intarray and contrib/ltree, where input of types query_int and ltxtquery had the same problem. Back-patch to all supported versions.
2010-12-10Fix efficiency problems in tuplestore_trim().Tom Lane
The original coding in tuplestore_trim() was only meant to work efficiently in cases where each trim call deleted most of the tuples in the store. Which, in fact, was the pattern of the original usage with a Material node supporting mark/restore operations underneath a MergeJoin. However, WindowAgg now uses tuplestores and it has considerably less friendly trimming behavior. In particular it can attempt to trim one tuple at a time off a large tuplestore. tuplestore_trim() had O(N^2) runtime in this situation because of repeatedly shifting its tuple pointer array. Fix by avoiding shifting the array until a reasonably large number of tuples have been deleted. This can waste some pointer space, but we do still reclaim the tuples themselves, so the percentage wastage should be pretty small. Per Jie Li's report of slow percent_rank() evaluation. cume_dist() and ntile() would certainly be affected as well, along with any other window function that has a moving frame start and requires reading substantially ahead of the current row. Back-patch to 8.4, where window functions were introduced. There's no need to tweak it before that.
2010-12-08Force default wal_sync_method to be fdatasync on Linux.Tom Lane
Recent versions of the Linux system header files cause xlogdefs.h to believe that open_datasync should be the default sync method, whereas formerly fdatasync was the default on Linux. open_datasync is a bad choice, first because it doesn't actually outperform fdatasync (in fact the reverse), and second because we try to use O_DIRECT with it, causing failures on certain filesystems (e.g., ext4 with data=journal option). This part of the patch is largely per a proposal from Marti Raudsepp. More extensive changes are likely to follow in HEAD, but this is as much change as we want to back-patch. Also clean up confusing code and incorrect documentation surrounding the fsync_writethrough option. Those changes shouldn't result in any actual behavioral change, but I chose to back-patch them anyway to keep the branches looking similar in this area. In 9.0 and HEAD, also do some copy-editing on the WAL Reliability documentation section. Back-patch to all supported branches, since any of them might get used on modern Linux versions.
2010-11-10Fix line_construct_pm() for the case of "infinite" (DBL_MAX) slope.Tom Lane
This code was just plain wrong: what you got was not a line through the given point but a line almost indistinguishable from the Y-axis, although not truly vertical. The only caller that tries to use this function with m == DBL_MAX is dist_ps_internal for the case where the lseg is horizontal; it would end up producing the distance from the given point to the place where the lseg's line crosses the Y-axis. That function is used by other operators too, so there are several operators that could compute wrong distances from a line segment to something else. Per bug #5745 from jindiax. Back-patch to all supported branches.
2010-11-02Ensure an index that uses a whole-row Var still depends on its table.Tom Lane
We failed to record any dependency on the underlying table for an index declared like "create index i on t (foo(t.*))". This would create trouble if the table were dropped without previously dropping the index. To fix, simplify some overly-cute code in index_create(), accepting the possibility that sometimes the whole-table dependency will be redundant. Also document this hazard in dependency.c. Per report from Kevin Grittner. In passing, prevent a core dump in pg_get_indexdef() if the index's table can't be found. I came across this while experimenting with Kevin's example. Not sure it's a real issue when the catalogs aren't corrupt, but might as well be cautious. Back-patch to all supported versions.
2010-09-27Add "(change requires restart)" note to some postgresql.conf parameters.Robert Haas
Devrim GÜNDÜZ
2010-09-22Re-allow input of Julian dates prior to 0001-01-01 AD.Tom Lane
This was unintentionally broken in 8.4 while tightening up checking of ordinary non-Julian date inputs to forbid references to "year zero". Per bug #5672 from Benjamin Gigot.
2010-09-22Convert cvsignore to gitignore, and add .gitignore for build targets.Magnus Hagander
2010-09-13Process options from the startup packed in walsender. Only few optionsHeikki Linnakangas
make sense for walsender, but for example application_name and client_encoding do. We still don't apply per-role settings from pg_db_role_setting, because that would require connecting to a database to read the table. Fujii Masao
2010-09-04Pad the ps_status display with nulls, not blanks, on Darwin.Tom Lane
A long time ago, this didn't work nicely, but it seems to work on all recent versions of OS X. The blank-pad method is less desirable since it results in lots of extra space in ps' output. Per Alexey Klyukin.
2010-09-02Fix up flushing of composite-type typcache entries to be driven directly byTom Lane
SI invalidation events, rather than indirectly through the relcache. In the previous coding, we had to flush a composite-type typcache entry whenever we discarded the corresponding relcache entry. This caused problems at least when testing with RELCACHE_FORCE_RELEASE, as shown in recent report from Jeff Davis, and might result in real-world problems given the kind of unexpected relcache flush that that test mechanism is intended to model. The new coding decouples relcache and typcache management, which is a good thing anyway from a structural perspective. The cost is that we have to search the typcache linearly to find entries that need to be flushed. There are a couple of ways we could avoid that, but at the moment it's not clear it's worth any extra trouble, because the typcache contains very few entries in typical operation. Back-patch to 8.2, the same as some other recent fixes in this general area. The patch could be carried back to 8.0 with some additional work, but given that it's only hypothetical whether we're fixing any problem observable in the field, it doesn't seem worth the work now.
2010-08-21Use a non-locale-dependent definition of isspace() in array_in/array_out.Tom Lane
array_in discards unquoted leading and trailing whitespace in array values, while array_out is careful to quote array elements that contain whitespace. This is problematic when the definition of "whitespace" varies between locales: array_in could drop characters that were meant to be part of the value. To avoid that, lock down "whitespace" to mean only the traditional six ASCII space characters. This change also works around a bug in OS X and some older BSD systems, in which isspace() could return true for character fragments in UTF8 locales. (There may be other places in PG where that bug could cause problems, but this is the only one complained of so far; see recent report from Steven Schlansker.) Back-patch to 9.0, but not further. Given the lack of previous reports of trouble, changing this behavior in stable branches seems to offer more risk of breaking applications than reward of avoiding problems.
2010-08-19Bring some sanity to the trace_recovery_messages code and docs.Tom Lane
Per gripe from Fujii Masao, though this is not exactly his proposed patch. Categorize as DEVELOPER_OPTIONS and set context PGC_SIGHUP, as per Fujii, but set the default to LOG because higher values aren't really sensible (see the code for trace_recovery()). Fix the documentation to agree with the code and to try to explain what the variable actually does. Get rid of no-op calls trace_recovery(LOG), which accomplish nothing except to demonstrate that this option confuses even its author.
2010-08-16Arrange to fsync the contents of lockfiles (both postmaster.pid and theTom Lane
socket lockfile) when writing them. The lack of an fsync here may well explain two different reports we've seen of corrupted lockfile contents, which doesn't particularly bother the running server but can prevent a new server from starting if the old one crashes. Per suggestion from Alvaro. Back-patch to all supported versions.
2010-08-13Fix Assert failure in PushOverrideSearchPath when trying to restore a searchTom Lane
path that specifies useTemp, but there is no active temp schema in the current session. (This can happen if the path was saved during a transaction that created a temp schema and was later rolled back.) For existing callers it's sufficient to ignore the useTemp flag in this case, though we might later want to offer an option to create a fresh temp schema. So far as I can tell this is just an Assert failure: in a non-assert build, the code would push a zero onto the new search path, which is useless but not very harmful. Per bug report from Heikki. Back-patch to 8.3; prior versions don't have this code.
2010-08-11The sanity check added to array_recv() wa a bit too tight; we mustHeikki Linnakangas
continue to accept an empty array with dimension information. array_send() can output such arrays. Per report from Vladimir Shakhov.
2010-08-05Remove the single-argument form of string_agg(). It added nothing much inTom Lane
functionality, while creating an ambiguity in usage with ORDER BY that at least two people have already gotten seriously confused by. Also, add an opr_sanity test to check that we don't in future violate the newly minted policy of not having built-in aggregates with the same name and different numbers of parameters. Per discussion of a complaint from Thom Brown.
2010-08-03Fix core dump in QTNodeCompare when tsquery_cmp() is applied to two emptyTom Lane
tsqueries. CompareTSQ has to have a guard for the case rather than blindly applying QTNodeCompare to random data past the end of the datums. Also, change QTNodeCompare to be a little less trusting: use an actual test rather than just Assert'ing that the input is sane. Problem encountered while investigating another issue (I saw a core dump in autoanalyze on a table containing multiple empty tsquery values). Back-patch to all branches with tsquery support. In HEAD, also fix some bizarre (though not outright wrong) coding in tsq_mcontains().
2010-08-02Fix an ancient typo that prevented the detection of conflicting fields whenTom Lane
interval input "invalid" was specified together with other fields. Spotted by Neil Conway with the help of a clang warning. Although this has been wrong since the interval code was written more than 10 years ago, it doesn't affect anything beyond which error message you get for a wrong input, so not worth back-patching very far.
2010-08-01Rewrite the rbtree routines so that an RBNode is the first field of theTom Lane
struct representing a tree entry, rather than being a separately allocated piece of storage. This API is at least as clean as the old one (if not more so --- there were some bizarre choices in there) and it permits a very substantial memory savings, on the order of 2X in ginbulk.c's usage. Also, fix minor memory leaks in code called by ginEntryInsert, in particular in ginInsertValue and entryFillRoot, as well as ginEntryInsert itself. These leaks resulted in the GIN index build context continuing to bloat even after we'd filled it to maintenance_work_mem and started to dump data out to the index. In combination these fixes restore the GIN index build code to honoring the maintenance_work_mem limit about as well as it did in 8.4. Speed seems on par with 8.4 too, maybe even a bit faster, for a non-pathological case in which HEAD was formerly slower. Back-patch to 9.0 so we don't have a performance regression from 8.4.
2010-07-18Remove unnecessary "Not safe to send CSV data" complaint from elog.c's fallbackTom Lane
path when CSV logging is configured but not yet operational. It's sufficient to send the message to stderr, as we were already doing, and the "Not safe" gripe has already confused at least two core members ... Backpatch to 9.0, but not further --- doesn't seem appropriate to change this behavior in stable branches.
2010-07-13Oops, in the previous fix to prevent a cursor that's being used in a FORHeikki Linnakangas
loop from being dropped, I missed subtransaction cleanup. Pinned portals must be dropped at subtransaction cleanup just as they are at main transaction cleanup. Per bug #5556 by Robert Walker. Backpatch to 8.0, 7.4 didn't have subtransactions.
2010-07-09Avoid an Assert failure in deconstruct_array() by making get_attstatsslot()Tom Lane
use the actual element type of the array it's disassembling, rather than trusting the type OID passed in by its caller. This is needed because sometimes the planner passes in a type OID that's only binary-compatible with the target column's type, rather than being an exact match. Per an example from Bernd Helmle. Possibly we should refactor get_attstatsslot/free_attstatsslot to not expect the caller to supply type ID data at all, but for now I'll just do the minimum-change fix. Back-patch to 7.4. Bernd's test case only crashes back to 8.0, but since these subroutines are the same in 7.4, I suspect there may be variant cases that would crash 7.4 as well.
2010-07-09Fix ruleutils' get_variable() to print something useful for Vars referencingTom Lane
resjunk outputs of subquery tlists, instead of throwing an error. Per bug #5548 from Daniel Grace. We might at some point find we ought to back-patch this further than 9.0, but I think that such Vars can only occur as resjunk members of upper-level tlists, in which case the problem can't arise because prior versions didn't print resjunk tlist items in EXPLAIN VERBOSE.
2010-07-07Adjust mbutils.c so it won't get broken by future pgindent runs.Tom Lane
To do that, replace L'\0' by (WCHAR) 0. Perhaps someday we should teach pgindent about wide-character literals, but so long as this is the only use-case in the entire Postgres sources, a workaround seems easier.
2010-07-06Make log_temp_files based on kB, and revert docs & comments to match.Robert Haas
Per extensive discussion on pgsql-hackers. We are deliberately not back-patching this even though the behavior of 8.3 and 8.4 is unquestionably broken, for fear of breaking existing users of this parameter. This incompatibility should be release-noted.
2010-07-06Undo pgindent breakage (again). Per buildfarm.Tom Lane
2010-07-06pgindent run for 9.0, second runBruce Momjian
2010-07-05The previous fix in CVS HEAD and 8.4 for handling the case where a cursorHeikki Linnakangas
being used in a PL/pgSQL FOR loop is closed was inadequate, as Tom Lane pointed out. The bug affects FOR statement variants too, because you can close an implicitly created cursor too by guessing the "<unnamed portal X>" name created for it. To fix that, "pin" the portal to prevent it from being dropped while it's being used in a PL/pgSQL FOR loop. Backpatch all the way to 7.4 which is the oldest supported version.
2010-07-03Make vacuum_defer_cleanup_age be PGC_SIGHUP level, since it's not sensibleTom Lane
to have different values in different processes of the primary server. Also put it into the "Streaming Replication" GUC category; it doesn't belong in "Standby Servers" because you use it on the master not the standby. In passing also correct guc.c's idea of wal_keep_segments' category.
2010-07-03Replace max_standby_delay with two parameters, max_standby_archive_delay andTom Lane
max_standby_streaming_delay, and revise the implementation to avoid assuming that timestamps found in WAL records can meaningfully be compared to clock time on the standby server. Instead, the delay limits are compared to the elapsed time since we last obtained a new WAL segment from archive or since we were last "caught up" to WAL data arriving via streaming replication. This avoids problems with clock skew between primary and standby, as well as other corner cases that the original coding would misbehave in, such as the primary server having significant idle time between transactions. Per my complaint some time ago and considerable ensuing discussion. Do some desultory editing on the hot standby documentation, too.