Starting on 2023-08-03, this intermittently terminated a "pgbench -C"
test in CI. It could affect a high-client-count "pgbench" without "-C".
While parallel reindexdb and vacuumdb reach the same problematic check,
sufficient client count and/or connection turnover is less plausible for
them. Given the lack of examples from the buildfarm or from manual
builds, reproducing this must entail rare operating system
configurations. Also correct the associated error message, which was
wrong for non-Windows. Back-patch to v12, where the pgbench check first
appeared. While v11 vacuumdb has the problematic check, reaching it
with typical vacuumdb usage is implausible.
Reviewed by Thomas Munro.
Discussion: https://postgr.es/m/CA+hUKG+JwvTNdcyJTriy9BbtzF1veSRQ=9M_ZKFn9_LqE7Kp7Q@mail.gmail.com
While waiting for slots to become available in wait_on_slots() in
parallel_slot.c, the cancellation always relied on the first connection
in the set to do the job. This could cause problems when this slot's
socket is gone as PQgetCancel() would return NULL in this case. Rather
than always using the first connection, this changes the logic to use
the first valid connection for the cancellation.
Author: Ranier Vilela
Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/CAEudQAokk1h_pUwGXsYS4oVOuf35s1O2o3TXGHpV8=AWikvgHA@mail.gmail.com
Backpatch-through: 14
psql, pg_dump, and pg_amcheck share code to process object name
patterns like 'foo*.bar*' to match all tables with names starting in
'bar' that are in schemas starting with 'foo'. Before v14, any number
of extra name parts were silently ignored, so a command line '\d
foo.bar.baz.bletch.quux' was interpreted as '\d bletch.quux'. In v14,
as a result of commit 2c8726c4b0, we
instead treated this as a request for table quux in a schema named
'foo.bar.baz.bletch'. That caused problems for people like Justin
Pryzby who were accustomed to copying strings of the form
db.schema.table from messages generated by PostgreSQL itself and using
them as arguments to \d.
Accordingly, revise things so that if an object name pattern contains
more parts than we're expecting, we throw an error, unless there's
exactly one extra part and it matches the current database name.
That way, thisdb.myschema.mytable is accepted as meaning just
myschema.mytable, but otherdb.myschema.mytable is an error, and so
is some.random.garbage.myschema.mytable.
Mark Dilger, per report from Justin Pryzby and discussion among
various people.
Discussion: https://www.postgresql.org/message-id/20211013165426.GD27491%40telsasoft.com
Most of these are cases where we could call memcpy() or other libc
functions with a NULL pointer and a zero count, which is forbidden
by POSIX even though every production version of libc allows it.
We've fixed such things before in a piecemeal way, but apparently
never made an effort to try to get them all. I don't claim that
this patch does so either, but it gets every failure I observe in
check-world, using clang 12.0.1 on current RHEL8.
numeric.c has a different issue that the sanitizer doesn't like:
"ln(-1.0)" will compute log10(0) and then try to assign the
resulting -Inf to an integer variable. We don't actually use the
result in such a case, so there's no live bug.
Back-patch to all supported branches, with the idea that we might
start running a buildfarm member that tests this case. This includes
back-patching c1132aae3 (Check the size in COPY_POINTER_FIELD),
which previously silenced some of these issues in copyfuncs.c.
Discussion: https://postgr.es/m/CALNJ-vT9r0DSsAOw9OXVJFxLENoVS_68kJ5x0p44atoYH+H4dg@mail.gmail.com
It seems highly unlikely that gettext() can be relied on to be
async-signal-safe. psql used to understand that, but someone got
it wrong long ago in the src/bin/scripts/ version of handle_sigint,
and then the bad idea was perpetuated when those two versions were
unified into src/fe_utils/cancel.c.
I'm unsure why there have not been field complaints about this
... maybe gettext() is signal-safe once it's translated at least
one message? But we have no business assuming any such thing.
In cancel.c (v13 and up), I preserved our ability to localize
"Cancel request sent" messages by invoking gettext() before
the signal handler is set up. In earlier branches I just made
src/bin/scripts/ not localize those messages, as psql did then.
(Just for extra unsafety, the src/bin/scripts/ version was
invoking fprintf() from a signal handler. Sigh.)
Noted while fixing signal-safety issues in PQcancel() itself.
Back-patch to all supported branches.
Discussion: https://postgr.es/m/2937814.1641960929@sss.pgh.pa.us
An incorrectly-encoded multibyte character near the end of a string
could cause various processing loops to run past the string's
terminating NUL, with results ranging from no detectable issue to
a program crash, depending on what happens to be in the following
memory.
This isn't an issue in the server, because we take care to verify
the encoding of strings before doing any interesting processing
on them. However, that lack of care leaked into client-side code
which shouldn't assume that anyone has validated the encoding of
its input.
Although this is certainly a bug worth fixing, the PG security team
elected not to regard it as a security issue, primarily because
any untrusted text should be sanitized by PQescapeLiteral or
the like before being incorporated into a SQL or psql command.
(If an app fails to do so, the same technique can be used to
cause SQL injection, with probably much more dire consequences
than a mere client-program crash.) Those functions were already
made proof against this class of problem, cf CVE-2006-2313.
To fix, invent PQmblenBounded() which is like PQmblen() except it
won't return more than the number of bytes remaining in the string.
In HEAD we can make this a new libpq function, as PQmblen() is.
It seems imprudent to change libpq's API in stable branches though,
so in the back branches define PQmblenBounded as a macro in the files
that need it. (Note that just changing PQmblen's behavior would not
be a good idea; notably, it would completely break the escaping
functions' defense against this exact problem. So we just want a
version for those callers that don't have any better way of handling
this issue.)
Per private report from houjingyi. Back-patch to all supported branches.
When dealing with overloaded function or operator names, having
to look through a long list of matches is tedious. Let's extend
these commands to allow specification of (input) argument types
to let such results be trimmed down. Each additional argument
is treated the same as the pattern argument of \dT and matched
against the appropriate argument's type name.
While at it, fix \dT (and these new options) to recognize the
usual notation of "foo[]" for "the array type over foo", and
to handle the special abbreviations allowed by the backend
grammar, such as "int" for "integer".
Greg Sabino Mullane, revised rather significantly by me
Discussion: https://postgr.es/m/CAKAnmmLF9Hhu02N+s7uAyLc5J1xZReg72HQUoiKhNiJV3_jACQ@mail.gmail.com
This adds support for writing CREATE FUNCTION and CREATE PROCEDURE
statements for language SQL with a function body that conforms to the
SQL standard and is portable to other implementations.
Instead of the PostgreSQL-specific AS $$ string literal $$ syntax,
this allows writing out the SQL statements making up the body
unquoted, either as a single statement:
CREATE FUNCTION add(a integer, b integer) RETURNS integer
LANGUAGE SQL
RETURN a + b;
or as a block
CREATE PROCEDURE insert_data(a integer, b integer)
LANGUAGE SQL
BEGIN ATOMIC
INSERT INTO tbl VALUES (a);
INSERT INTO tbl VALUES (b);
END;
The function body is parsed at function definition time and stored as
expression nodes in a new pg_proc column prosqlbody. So at run time,
no further parsing is required.
However, this form does not support polymorphic arguments, because
there is no more parse analysis done at call time.
Dependencies between the function and the objects it uses are fully
tracked.
A new RETURN statement is introduced. This can only be used inside
function bodies. Internally, it is treated much like a SELECT
statement.
psql needs some new intelligence to keep track of function body
boundaries so that it doesn't send off statements when it sees
semicolons that are inside a function body.
Tested-by: Jaime Casanova <jcasanov@systemguards.com.ec>
Reviewed-by: Julien Rouhaud <rjuju123@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/1c11f1eb-f00c-43b7-799d-2d44132c02d7@2ndquadrant.com
We were never doing clearerr() on the output stream, which results in a
message being printed after each result once an EOF is seen:
could not print result table: Success
This message was added by commit b03436994b (in the pg13 era); before
that, the error indicator would never be examined. So backpatch only
that far back, even though the actual bug (to wit: the fact that the
error indicator is never cleared) is older.
Create a wrapper object, ParallelSlotArray, to encapsulate the
number of slots and the slot array itself, plus some other relevant
bits of information. This reduces the number of parameters we have
to pass around all over the place.
Allow for a ParallelSlotArray to contain slots connected to
different databases within a single cluster. The current clients
of this mechanism don't need this, but it is expected to be used
by future patches.
Defer connecting to databases until we actually need the connection
for something. This is a slight behavior change for vacuumdb and
reindexdb. If you specify a number of jobs that is larger than the
number of objects, the extra connections will now not be used.
But, on the other hand, if you specify a number of jobs that is
so large that it's going to fail, the failure would previously have
happened before any operations were actually started, and now it
won't.
Mark Dilger, reviewed by me.
Discussion: http://postgr.es/m/12ED3DA8-25F0-4B68-937D-D907CFBF08E7@enterprisedb.com
Discussion: http://postgr.es/m/BA592F2D-F928-46FF-9516-2B827F067F57@enterprisedb.com
The parallel slots infrastructure (which implements client-side
multiplexing of server connections doing similar things, not
threading or multiple processes or anything like that) are moved from
src/bin/scripts/scripts_parallel.c to src/fe_utils/parallel_slot.c.
The functions consumeQueryResult() and processQueryResult() which were
previously part of src/bin/scripts/common.c are now moved into that
file as well, becoming static helper functions. This might need to be
changed in the future, but currently they're not used for anything
else.
Some other functions from src/bin/scripts/common.c are moved to to
src/fe_utils and are split up among several files. connectDatabase(),
connectMaintenanceDatabase(), and disconnectDatabase() are moved to
connect_utils.c. executeQuery(), executeCommand(), and
executeMaintenanceCommand() are move to query_utils.c.
handle_help_version_opts() is moved to option_utils.c.
Mark Dilger, reviewed by me. The larger patch series of which this is
a part has also had review from Peter Geoghegan, Andres Freund, Álvaro
Herrera, Michael Paquier, and Amul Sul, but I don't know whether any
of them have reviewed this bit specifically.
Discussion: http://postgr.es/m/12ED3DA8-25F0-4B68-937D-D907CFBF08E7@enterprisedb.com
Discussion: http://postgr.es/m/5F743835-3399-419C-8324-2D424237E999@enterprisedb.com
Discussion: http://postgr.es/m/70655DF3-33CE-4527-9A4D-DDEB582B6BA0@enterprisedb.com
The logic for converting the shell-glob-like syntax supported by
utilities like psql and pg_dump to regular expression is
extracted into a new function patternToSQLRegex. The existing
function processSQLNamePattern now uses this function as a
subroutine.
patternToSQLRegex is a little more general than what is required
by processSQLNamePattern. That function is only interested in
patterns that can have up to 2 parts, a schema and a relation;
but patternToSQLRegex can limit the maximum number of parts to
between 1 and 3, so that patterns can look like either
"database.schema.relation", "schema.relation", or "relation"
depending on how it's invoked and what the user specifies.
processSQLNamePattern only passes two buffers, so works exactly
the same as before, always interpreting the pattern as either
a "schema.relation" pattern or a "relation" pattern. But,
future callers can use this function in other ways.
Mark Dilger, reviewed by me. The larger patch series of which this is
a part has also had review from Peter Geoghegan, Andres Freund, Álvaro
Herrera, Michael Paquier, and Amul Sul, but I don't know whether
any of them have reviewed this bit specifically.
Discussion: http://postgr.es/m/12ED3DA8-25F0-4B68-937D-D907CFBF08E7@enterprisedb.com
Discussion: http://postgr.es/m/5F743835-3399-419C-8324-2D424237E999@enterprisedb.com
Discussion: http://postgr.es/m/70655DF3-33CE-4527-9A4D-DDEB582B6BA0@enterprisedb.com
On the same reasoning as in commit 36b931214, forbid using custom
oid_symbol macros in pg_type as well as pg_proc, so that we always
rely on the predictable macro names generated by genbki.pl.
We do continue to grant grandfather status to the names CASHOID and
LSNOID, although those are now considered deprecated aliases for the
preferred names MONEYOID and PG_LSNOID. This is because there's
likely to be client-side code using the old names, and this bout of
neatnik-ism doesn't quite seem worth breaking client code.
There might be a case for grandfathering EVTTRIGGEROID, too, since
externally-maintained PLs may reference that symbol. But renaming
such references to EVENT_TRIGGEROID doesn't seem like a particularly
heavy lift --- we make far more significant backend API changes in
every major release. For now I didn't add that, but we could
reconsider if there's pushback.
The other names changed here seem pretty unlikely to have any outside
uses. Again, we could add alias macros if there are complaints, but
for now I didn't.
As before, no need for a catversion bump.
John Naylor
Discussion: https://postgr.es/m/CAFBsxsHpCbjfoddNGpnnnY5pHwckWfiYkMYSF74PmP1su0+ZOw@mail.gmail.com
Existing code used various inconsistent ways to printf struct stat's
st_size member. The type of that is off_t, which is in most cases a
signed 64-bit integer, so use the long long int format for it.
Any libpq client can use the header. Clients include backend components
postgres_fdw, dblink, and logical replication apply worker. Back-patch
to v10, because another fix needs this. In released branches, just copy
the header and keep the original.
Commit 54cd4f045 added some kluges to work around an old glibc bug,
namely that %.*s could misbehave if glibc thought any characters in
the supplied string were incorrectly encoded. Now that we use our
own snprintf.c implementation, we need not worry about that bug (even
if it still exists in the wild). Revert a couple of particularly
ugly hacks, and remove or improve assorted comments.
Note that there can still be encoding-related hazards here: blindly
clipping at a fixed length risks producing wrongly-encoded output
if the clip splits a multibyte character. However, code that's
doing correct multibyte-aware clipping doesn't really need a comment
about that, while code that isn't needs an explanation why not,
rather than a red-herring comment about an obsolete bug.
Discussion: https://postgr.es/m/279428.1593373684@sss.pgh.pa.us
fe_archive.c was compiled only for the frontend in src/common/, but as
it will never share anything with the backend, it makes most sense to
move this file to src/fe_utils/.
Reported-by: Peter Eisentraut
Discussion: https://postgr.es/m/e9766d71-8655-ac86-bdf6-77e0e7169977@2ndquadrant.com
Backpatch-through: 13
As it stands, this flag is only set when we've successfully sent a
cancel request, not if we get SIGINT and then fail to send a cancel.
However, for almost all callers, that's the Wrong Thing: we'd prefer
to abort processing after control-C even if no cancel could be sent.
As an example, since commit 1d468b9ad "pgbench -i" fails to give up
sending COPY data even after control-C, if the postmaster has been
stopped, which is clearly not what the code intends and not what anyone
would want. (The fact that it keeps going at all is the fault of a
separate bug in libpq, but not letting CancelRequested become set is
clearly not what we want here.)
The sole exception, as far as I can find, is that scripts_parallel.c's
ParallelSlotsGetIdle tries to consume a query result after issuing a
cancel, which of course might not terminate quickly if no cancel
happened. But that behavior was poorly thought out too. No user of
ParallelSlotsGetIdle tries to continue processing after a cancel,
so there is really no point in trying to clear the connection's state.
Moreover this has the same defect as for other users of cancel.c,
that if the cancel request fails for some reason then we end up with
control-C being completely ignored. (On top of that, select_loop failed
to distinguish clearly between SIGINT and other reasons for select(2)
failing, which means that it's possible that the existing code would
think that a cancel has been sent when it hasn't.)
Hence, redefine CancelRequested as simply meaning that SIGINT was
received. We could add a second flag with the other meaning, but
in the absence of any compelling argument why such a flag is needed,
I think it would just offer an opportunity for future callers to
get it wrong. Also remove the consumeQueryResult call in
ParallelSlotsGetIdle's failure exit. In passing, simplify the
API of select_loop.
It would now be possible to re-unify psql's cancel_pressed with
CancelRequested, partly undoing 5d43c3c54. But I'm not really
convinced that that's worth the trouble, so I left psql alone,
other than fixing a misleading comment.
This code is new in v13 (cf a4fd3aa71), so no need for back-patch.
Per investigation of a complaint from Andres Freund.
Discussion: https://postgr.es/m/20200603201242.ofvm4jztpqytwfye@alap3.anarazel.de
Similar to xid, but 64 bits wide. This new type is suitable for use in
various system views and administration functions.
Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com>
Reviewed-by: Takao Fujii <btfujiitkp@oss.nttdata.com>
Reviewed-by: Yoshikazu Imai <imai.yoshikazu@fujitsu.com>
Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com>
Discussion: https://postgr.es/m/20190725000636.666m5mad25wfbrri%40alap3.anarazel.de
Commit caba97a9d9 changed pg_basebackup -F plain -R so that
it overwrote postgresql.auto.conf in the backup, with new connection
setting. This could cause the existing postgresql.auto.conf settings
in the server to get lost unexpectedly. This is a bug.
This commit fixes the bug by making pg_basebackup -F plain -R
append the connection setting into postgresql.auto.conf in the backup.
Author: Fujii Masao
Reviewed-by: Sergei Kornilov
Discussion: https://postgr.es/m/250dcf2a-94e7-c05e-824a-73cfb38a48a4@oss.nttdata.com
Previously, the core scanner's yy_transition[] array had 37045 elements.
Since that number is larger than INT16_MAX, Flex generated the array to
contain 32-bit integers. By reimplementing some of the bulkier scanner
rules, this patch reduces the array to 20495 elements. The much smaller
total length, combined with the consequent use of 16-bit integers for
the array elements reduces the binary size by over 200kB. This was
accomplished in two ways:
1. Consolidate handling of quote continuations into a new start condition,
rather than duplicating that logic for five different string types.
2. Treat Unicode strings and identifiers followed by a UESCAPE sequence
as three separate tokens, rather than one. The logic to de-escape
Unicode strings is moved to the filter code in parser.c, which already
had the ability to provide special processing for token sequences.
While we could have implemented the conversion in the grammar, that
approach was rejected for performance and maintainability reasons.
Performance in microbenchmarks of raw parsing seems equal or slightly
faster in most cases, and it's reasonable to expect that in real-world
usage (with more competition for the CPU cache) there will be a larger
win. The exception is UESCAPE sequences; lexing those is about 10%
slower, primarily because the scanner now has to be called three times
rather than one. This seems acceptable since that feature is very
rarely used.
The psql and epcg lexers are likewise modified, primarily because we
want to keep them all in sync. Since those lexers don't use the
space-hogging -CF option, the space savings is much less, but it's
still good for perhaps 10kB apiece.
While at it, merge the ecpg lexer's handling of C-style comments used
in SQL and in C. Those have different rules regarding nested comments,
but since we already have the ability to keep track of the previous
start condition, we can use that to handle both cases within a single
start condition. This matches the core scanner more closely.
John Naylor
Discussion: https://postgr.es/m/CACPNZCvaoa3EgVWm5yZhcSTX6RAtaLgniCPcBVOCwm8h3xpWkw@mail.gmail.com
The refactoring done in a4fd3aa for query cancellation has messed up
with the logic in psql by mixing CancelRequested and cancel_pressed,
breaking for example \watch. The former would be switched to true if a
cancellation request has been attempted and that it actually succeeded,
and the latter tracks if a cancellation attempt has been done.
This commit brings back the code of psql to a state consistent to what
it was before a4fd3aa, without giving up on the refactoring pieces
introduced. It should be actually possible to merge more both flags as
their concepts are close enough, however note that psql's --single-step
mode relies on cancel_pressed to be always set, so this requires more
careful analysis left for later.
While on it, fix the declarations of CancelRequested (in cancel.c) and
cancel_pressed (in psql) to be volatile sig_atomic_t. Previously,
both were declared as booleans, which should be fine on modern
platforms, but the C standard recommends the use of sig_atomic_t for
variables used in signal handlers. Note that since its introduction in
a1792320, CancelRequested declaration was not volatile.
Reported-by: Jeff Janes
Author: Michael Paquier
Discussion: https://postgr.es/m/CAMkU=1zpoUDGKqWKuMWkj7t-bOCaJDx0r=5te_-d0B2HVLABXg@mail.gmail.com
Originally, this code was duplicated in src/bin/psql/ and
src/bin/scripts/, but it can be useful for other frontend applications,
like pgbench. This refactoring offers the possibility to setup a custom
callback which would get called in the signal handler for SIGINT or when
the interruption console events happen on Windows.
Author: Fabien Coelho, with contributions from Michael Paquier
Reviewed-by: Álvaro Herrera, Ibrar Ahmed
Discussion: https://postgr.es/m/alpine.DEB.2.21.1910311939430.27369@lancre
When maintaining or merging patches, one of the most common sources
for conflicts are the list of objects in makefiles. Especially when
the split across lines has been changed on both sides, which is
somewhat common due to attempting to stay below 80 columns, those
conflicts are unnecessarily laborious to resolve.
By splitting, and alphabetically sorting, OBJS style lines into one
object per line, conflicts should be less frequent, and easier to
resolve when they still occur.
Author: Andres Freund
Discussion: https://postgr.es/m/20191029200901.vww4idgcxv74cwes@alap3.anarazel.de
When an FK constraint is created, it needs the index on the referenced
table to exist and be valid. When doing parallel pg_restore and the
referenced table was partitioned, this condition can sometimes not be
met, because pg_dump didn't emit sufficient object dependencies to
ensure so; this means that parallel pg_restore would fail in certain
conditions. Fix by having pg_dump make the FK constraint object
dependent on the partition attachment objects for the constraint's
referenced index.
This has been broken since f56f8f8da6, so backpatch to Postgres 12.
Discussion: https://postgr.es/m/20191005224333.GA9738@alvherre.pgsql
When building a list of relations for a parallel processing of a schema
or a database (or just a single-entry list for the non-parallel case
with the database name), the list is allocated and built on-the-fly for
each database processed, leaking after one database-level reindex is
done. This accumulates leaks when processing all databases, and could
become a visible issue with thousands of relations.
This is fixed by introducing a new routine in simple_list.c to free all
the elements in a simple list made of strings or OIDs. The header of
the list may be using a variable declaration or an allocated pointer,
so we don't have a routine to free this part to keep the interface
simple.
Per report from coverity for an issue introduced by 5ab892c, and
valgrind complains about the leak as well. The idea to introduce a new
routine in simple_list.c is from Tom Lane.
Author: Michael Paquier
Reviewed-by: Tom Lane
This changes various places where appendPQExpBuffer was used in places
where it was possible to use appendPQExpBufferStr, and likewise for
appendStringInfo and appendStringInfoString. This is really just a
stylistic improvement, but there are also small performance gains to be
had from doing this.
Discussion: http://postgr.es/m/CAKJS1f9P=M-3ULmPvr8iCno8yvfDViHibJjpriHU8+SXUgeZ=w@mail.gmail.com
The original placement of this module in src/fe_utils/ is ill-considered,
because several src/common/ modules have dependencies on it, meaning that
libpgcommon and libpgfeutils now have mutual dependencies. That makes it
pointless to have distinct libraries at all. The intended design is that
libpgcommon is lower-level than libpgfeutils, so only dependencies from
the latter to the former are acceptable.
We already have the precedent that fe_memutils and a couple of other
modules in src/common/ are frontend-only, so it's not stretching anything
out of whack to treat logging.c as a frontend-only module in src/common/.
To the extent that such modules help provide a common frontend/backend
environment for the rest of common/ to use, it's a reasonable design.
(logging.c does not yet provide an ereport() emulation, but one can
dream.)
Hence, move these files over, and revert basically all of the build-system
changes made by commit cc8d41511. There are no places that need to grow
new dependencies on libpgcommon, further reinforcing the idea that this
is the right solution.
Discussion: https://postgr.es/m/a912ffff-f6e4-778a-c86a-cf5c47a12933@2ndquadrant.com
Prior to v12, if you used a collation-sensitive regex feature in a
pattern handled by processSQLNamePattern() (for instance, \d '\\w+'
in psql), the behavior you got matched the database's default collation.
Since commit 586b98fdf you'd usually get C-collation behavior, because
the catalog "name"-type columns are now marked as COLLATE "C". Add
explicit COLLATE specifications to restore the prior behavior.
(Note for whoever writes the v12 release notes: the need for this shows
that while 586b98fdf preserved pre-v12 behavior of "name" columns for
simple comparison operators, it changed the behavior of regex operators
on those columns. Although this patch fixes it for pattern matches
generated by our own tools, user-written queries will still be affected.
So we'd better mention this issue as a compatibility item.)
Daniel Vérité
Discussion: https://postgr.es/m/701e51f0-0ec0-4e70-a365-1958d66dd8d2@manitou-mail.org
This unifies the various ad hoc logging (message printing, error
printing) systems used throughout the command-line programs.
Features:
- Program name is automatically prefixed.
- Message string does not end with newline. This removes a common
source of inconsistencies and omissions.
- Additionally, a final newline is automatically stripped, simplifying
use of PQerrorMessage() etc., another common source of mistakes.
- I converted error message strings to use %m where possible.
- As a result of the above several points, more translatable message
strings can be shared between different components and between
frontends and backend, without gratuitous punctuation or whitespace
differences.
- There is support for setting a "log level". This is not meant to be
user-facing, but can be used internally to implement debug or
verbose modes.
- Lazy argument evaluation, so no significant overhead if logging at
some level is disabled.
- Some color in the messages, similar to gcc and clang. Set
PG_COLOR=auto to try it out. Some colors are predefined, but can be
customized by setting PG_COLORS.
- Common files (common/, fe_utils/, etc.) can handle logging much more
simply by just using one API without worrying too much about the
context of the calling program, requiring callbacks, or having to
pass "progname" around everywhere.
- Some programs called setvbuf() to make sure that stderr is
unbuffered, even on Windows. But not all programs did that. This
is now done centrally.
Soft goals:
- Reduces vertical space use and visual complexity of error reporting
in the source code.
- Encourages more deliberate classification of messages. For example,
in some cases it wasn't clear without analyzing the surrounding code
whether a message was meant as an error or just an info.
- Concepts and terms are vaguely aligned with popular logging
frameworks such as log4j and Python logging.
This is all just about printing stuff out. Nothing affects program
flow (e.g., fatal exits). The uses are just too varied to do that.
Some existing code had wrappers that do some kind of print-and-exit,
and I adapted those.
I tried to keep the output mostly the same, but there is a lot of
historical baggage to unwind and special cases to consider, and I
might not always have succeeded. One significant change is that
pg_rewind used to write all error messages to stdout. That is now
changed to stderr.
Reviewed-by: Donald Dong <xdong@csumb.edu>
Reviewed-by: Arthur Zakirov <a.zakirov@postgrespro.ru>
Discussion: https://www.postgresql.org/message-id/flat/6a609b43-4f57-7348-6480-bd022f924310@2ndquadrant.com
Partial revert of commit 6260cc550b, "pgbench: add \cset and \gset
commands".
While \gset is widely considered a useful and necessary tool for user-
defined benchmarks, \cset does not have as much value, and its
implementation was considered "not to be up to project standards"
(though I, Álvaro, can't quite understand exactly how). Therefore,
remove \cset.
Author: Fabien Coelho
Discussion: https://postgr.es/m/alpine.DEB.2.21.1903230716030.18811@lancre
Discussion: https://postgr.es/m/201901101900.mv7zduch6sad@alvherre.pgsql
These commands allow assignment of values produced by queries to pgbench
variables, where they can be used by further commands. \gset terminates
a command sequence (just like a bare semicolon); \cset separates
multiple queries in a compound command, like an escaped semicolon (\;).
A prefix can be provided to the \-command and is prepended to the name
of each output column to produce the final variable name.
This feature allows pgbench scripts to react meaningfully to the actual
database contents, allowing more powerful benchmarks to be written.
Authors: Fabien Coelho, Álvaro Herrera
Reviewed-by: Amit Langote <Langote_Amit_f8@lab.ntt.co.jp>
Reviewed-by: Stephen Frost <sfrost@snowman.net>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Tatsuo Ishii <ishii@sraoss.co.jp>
Reviewed-by: Rafia Sabih <rafia.sabih@enterprisedb.com>
Discussion: https://postgr.es/m/alpine.DEB.2.20.1607091005330.3412@sto
Previously, ScanKeywordLookup was passed an array of string pointers.
This had some performance deficiencies: the strings themselves might
be scattered all over the place depending on the compiler (and some
quick checking shows that at least with gcc-on-Linux, they indeed
weren't reliably close together). That led to very cache-unfriendly
behavior as the binary search touched strings in many different pages.
Also, depending on the platform, the string pointers might need to
be adjusted at program start, so that they couldn't be simple constant
data. And the ScanKeyword struct had been designed with an eye to
32-bit machines originally; on 64-bit it requires 16 bytes per
keyword, making it even more cache-unfriendly.
Redesign so that the keyword strings themselves are allocated
consecutively (as part of one big char-string constant), thereby
eliminating the touch-lots-of-unrelated-pages syndrome. And get
rid of the ScanKeyword array in favor of three separate arrays:
uint16 offsets into the keyword array, uint16 token codes, and
uint8 keyword categories. That reduces the overhead per keyword
to 5 bytes instead of 16 (even less in programs that only need
one of the token codes and categories); moreover, the binary search
only touches the offsets array, further reducing its cache footprint.
This also lets us put the token codes somewhere else than the
keyword strings are, which avoids some unpleasant build dependencies.
While we're at it, wrap the data used by ScanKeywordLookup into
a struct that can be treated as an opaque type by most callers.
That doesn't change things much right now, but it will make it
less painful to switch to a hash-based lookup method, as is being
discussed in the mailing list thread.
Most of the change here is associated with adding a generator
script that can build the new data structure from the same
list-of-PG_KEYWORD header representation we used before.
The PG_KEYWORD lists that plpgsql and ecpg used to embed in
their scanner .c files have to be moved into headers, and the
Makefiles have to be taught to invoke the generator script.
This work is also necessary if we're to consider hash-based lookup,
since the generator script is what would be responsible for
constructing a hash table.
Aside from saving a few kilobytes in each program that includes
the keyword table, this seems to speed up raw parsing (flex+bison)
by a few percent. So it's worth doing even as it stands, though
we think we can gain even more with a follow-on patch to switch
to hash-based lookup.
John Naylor, with further hacking by me
Discussion: https://postgr.es/m/CAJVSVGXdFVU2sgym89XPL=Lv1zOS5=EHHQ8XWNzFL=mTXkKMLw@mail.gmail.com
latex_escaped_print() mistranslated \ and failed to provide any translation
for # ^ and ~, all of which would typically lead to LaTeX document syntax
errors. In addition it didn't translate < > and |, which would typically
render as unexpected characters.
To some extent this represents shortcomings in ancient versions of LaTeX,
which if memory serves had no easy way to render these control characters
as ASCII text. But that's been fixed for, um, decades. In any case there
is no value in emitting guaranteed-to-fail output for these characters.
Noted while fooling with test cases added by commit 9a98984f4. Back-patch
the code change to all supported versions.
"\pset format csv", or --csv, selects comma-separated values table format.
This is compliant with RFC 4180, except that we aren't too picky about
whether the record separator is LF or CRLF; also, the user may choose a
field separator other than comma.
This output format is directly compatible with the server's COPY CSV
format, and will also be useful as input to other programs. It's
considerably safer for that purpose than the old recommendation to
use "unaligned" format, since the latter couldn't handle data
containing the field separator character.
Daniel Vérité, reviewed by Fabien Coelho and David Fetter, some
tweaking by me
Discussion: https://postgr.es/m/a8de371e-006f-4f92-ab72-2bbe3ee78f03@manitou-mail.org
The realfail1 and realfail2 backup-prevention rules always returned
token type FCONST, ignoring the possibility that what we've scanned
is more appropriately described as ICONST. I think that at the
time that code was added, it might actually have been safe to not
distinguish; but since we started allowing AS-less aliases in SELECT
target lists, it's definitely legal to have a number immediately
followed by an identifier.
In the SELECT case, it seems there's no visible consequence because
make_const() will change the type back to integer anyway. But I'm
worried that there are other contexts, or will be in future, where
it's more important to get the constant's type right.
Hence, use process_integer_literal to correctly determine which
token type to return.
Arguably this is a bug fix, but given the lack of evidence of
user-visible problems, I'll refrain from back-patching.
Discussion: https://postgr.es/m/21364.1542136808@sss.pgh.pa.us
Noah Misch