The original code was a bit clunky; make it more amenable for further
reuse by creating a new Perl package PostgresNode, which is an
object-oriented representation of a single server, with some support
routines such as init, start, stop, psql. This serves as a better basis
on which to build further test code, and enables writing tests that use
more than one server without too much complication.
This commit modifies a lot of the existing test files, mostly to remove
explicit calls to system commands (pg_ctl) replacing them with method
calls of a PostgresNode object. The result is quite a bit more
straightforward.
Also move some initialization code to BEGIN and INIT blocks instead of
having it straight in as top-level code.
This commit also introduces package RecursiveCopy so that we can copy
whole directories without having to depend on packages that may not be
present on vanilla Perl 5.8 installations.
I also ran perltidy on the modified files, which changes some code sites
that are not otherwise touched by this patch. I tried to avoid this,
but it ended up being more trouble than it's worth.
Authors: Michael Paquier, Álvaro Herrera
Review: Noah Misch
The POSIX standard for tar headers requires archive member sizes to be
printed in octal with at most 11 digits, limiting the representable file
size to 8GB. However, GNU tar and apparently most other modern tars
support a convention in which oversized values can be stored in base-256,
allowing any practical file to be a tar member. Adopt this convention
to remove two limitations:
* pg_dump with -Ft output format failed if the contents of any one table
exceeded 8GB.
* pg_basebackup failed if the data directory contained any file exceeding
8GB. (This would be a fatal problem for installations configured with a
table segment size of 8GB or more, and it has also been seen to fail when
large core dump files exist in the data directory.)
File sizes under 8GB are still printed in octal, so that no compatibility
issues are created except in cases that would have failed entirely before.
In addition, this patch fixes several bugs in the same area:
* In 9.3 and later, we'd defined tarCreateHeader's file-size argument as
size_t, which meant that on 32-bit machines it would write a corrupt tar
header for file sizes between 4GB and 8GB, even though no error was raised.
This broke both "pg_dump -Ft" and pg_basebackup for such cases.
* pg_restore from a tar archive would fail on tables of size between 4GB
and 8GB, on machines where either "size_t" or "unsigned long" is 32 bits.
This happened even with an archive file not affected by the previous bug.
* pg_basebackup would fail if there were files of size between 4GB and 8GB,
even on 64-bit machines.
* In 9.3 and later, "pg_basebackup -Ft" failed entirely, for any file size,
on 64-bit big-endian machines.
In view of these potential data-loss bugs, back-patch to all supported
branches, even though removal of the documented 8GB limit might otherwise
be considered a new feature rather than a bug fix.
Several versions of the perl that comes with the Msys DTK have been
found to have a bug that fails to recognize a ' before a multiline $ in
some circumstances. To work around the problem, use a character class
for the '. Another solution would have been to use \n instead of $, but
that would have changed the test semantics very slightly.
Immediately starting to stream after --create-slot is inconvenient in a
number of situations (e.g. when configuring a slot for use in
recovery.conf) and it's easy to just call pg_receivexlog twice in the
rest of the cases.
Author: Michael Paquier
Discussion: CAB7nPqQ9qEtuDiKY3OpNzHcz5iUA+DUX9FcN9K8GUkCZvG7+Ew@mail.gmail.com
Backpatch: 9.5, where the option was introduced
The Msys DTK perl, which is required to run TAP tests under Msys as a
native perl won't recognize the correct virtual paths, has its osname
recorded in the Config module as 'msys' instead of 'MSWin32'. To avoid
having to repeat the test a variable is created that is true iff the
osname is either of these values, and is then used everywhere that
matters.
On Windows, use listen_address=127.0.0.1 to allow TCP connections. We were
already using "pg_regress --config-auth" to set up HBA appropriately. The
standard_initdb helper function now sets up the server's
unix_socket_directories or listen_addresses in the config file, so that
they don't need to be specified in the pg_ctl command line anymore. That
way, the pg_ctl invocations in test programs don't need to differ between
Windows and Unix.
Add another helper function to configure the server's pg_hba.conf to allow
replication connections. The configuration is done similarly to "pg_regress
--config-auth": trust on domain sockets on Unix, and SSPI authentication on
Windows.
Replace calls to "cat" and "touch" programs with built-in perl code, as
those programs don't normally exist on Windows.
Add instructions in the docs on how to install IPC::Run on Windows. Adjust
vcregress.pl to not replace PERL5LIB completely in vcregress.pl, because
otherwise cannot install IPC::Run in a non-standard location easily.
Michael Paquier, reviewed by Noah Misch, some additional tweaking by me.
This option specifies a replication slot for WAL streaming (-X stream),
so that there can be continuous replication slot use between WAL
streaming during the base backup and the start of regular streaming
replication.
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>
Per Coverity (not that any of these are so non-obvious that they should not
have been caught before commit). The extent of leakage is probably minor
to unnoticeable, but a leak is a leak. Back-patch as necessary.
Michael Paquier
pg_receivexlog and pg_recvlogical error out when --create-slot is
specified and a slot with the same name already exists. In some cases,
especially with pg_receivexlog, that's rather annoying and requires
additional scripting.
Backpatch to 9.5 as slot control functions have newly been added to
pg_receivexlog, and there doesn't seem much point leaving it in a less
useful state.
Discussion: 20150619144755.GG29350@alap3.anarazel.de
Create a log file for each test run. Stdout and stderr of the test script,
as well as any subprocesses run as part of the test, are redirected to
the log file. This makes it a lot easier to debug test failures. Also print
the test output (ok 12 - ... messages) to the log file, and the command
line of any external programs executed with the system_or_bail and run_log
functions. This makes it a lot easier to debug failing tests.
Modify some of the pg_ctl and other command invocations to not use 'silent'
or 'quiet' options, and don't redirect output to /dev/null, so that you get
all the information in the log instead.
In the passing, construct some command lines in a way that works if $tempdir
contains quote-characters. I haven't systematically gone through all of
them or tested that, so I don't know if this is enough to make that work.
pg_rewind tests had a custom mechanism for creating a similar log file. Use
the new generic facility instead.
Michael Paquier and me.
The previous coding tried to handle possible failures when fsyncing a
tty or pipe fd by accepting EINVAL - but apparently some
platforms (windows, OSX) don't reliably return that. So instead check
whether the output fd refers to a pipe or a tty when opening it.
Reported-By: Olivier Gosseaume, Marko Tiikkaja
Discussion: 559AF98B.3050901@joh.to
Backpatch to 9.4, where pg_recvlogical was added.
Patch by David Rowley. Backpatch to 9.5, as some of the calls were new in
9.5, and keeping the code in sync with master makes future backpatching
easier.
This supplements the GNU libc bug #6530 workarounds introduced in commit
54cd4f0457. On affected systems, a
tar-format pg_basebackup failed when some filename beneath the data
directory was not valid character data in the postmaster/walsender
locale. Back-patch to 9.1, where pg_basebackup was introduced. Extant,
bug-prone conversion specifications receive only ASCII bytes or involve
low-importance messages.
Windows can't reliably restore symbolic links from a tar format, so
instead during backup start we create a tablespace_map file, which is
used by the restoring postgres to create the correct links in pg_tblspc.
The backup protocol also now has an option to request this file to be
included in the backup stream, and this is used by pg_basebackup when
operating in tar mode.
This is done on all platforms, not just Windows.
This means that pg_basebackup will not not work in tar mode against 9.4
and older servers, as this protocol option isn't implemented there.
Amit Kapila, reviewed by Dilip Kumar, with a little editing from me.
The "check" target no longer needs to depend on "all", because it now
runs "install" directly, which in turn depends on "all". Doing both
will cause problems with parallel make, because two builds will run next
to each other.
Also remove the redirection of the temp-install output into a log file.
This was appropriate when this was done from within pg_regress, but now
it's just a regular make run, and especially with the above changes this
will now take the place of running the "all" target before the test
suites.
problem report by Jeff Janes, patch in part by Michael Paquier
The tar format (at least the version we are using), does not support
file names or symlink targets longer than 99 bytes. Until now, the tar
creation code would silently truncate any names that are too long. (Its
original application was pg_dump, where this never happens.) This
creates problems when running base backups over the replication
protocol.
The most important problem is when a tablespace path is longer than 99
bytes, which will result in a truncated tablespace path being backed up.
Less importantly, the basebackup protocol also promises to back up any
other files it happens to find in the data directory, which would also
lead to file name truncation if someone put a file with a long name in
there.
Now both of these cases result in an error during the backup.
Add tests that fail when a too-long file name or symlink is attempted to
be backed up.
Reviewed-by: Robert Hass <robertmhaas@gmail.com>
A oversight in 2c0a485896 causes 'could not create archive status file
"...": No such file or directory' errors in pg_receivexlog if the
target directory doesn't happen to contain a archive_status
directory. That's due to a stupidly left over 'true' constant instead
of mark_done being passed down to ProcessXLogDataMsg().
The bug is only present in the master branch, and luckily wasn't
released.
Spotted by Fujii Masao.
As every error in mark_file_as_archived() will lead to a failure of
pg_basebackup the FD leak couldn't ever lead to a real problem. It
seems better to fix the leak anyway though, rather than silence
Coverity, as the usage of the function might get extended or copied at
some point in the future.
Pointed out by Coverity.
Backpatch to 9.2, like the relevant part of the previous patch.
WAL (and timeline history) files created by pg_basebackup did not
maintain the new base backup's archive status. That's currently not a
problem if the new node is used as a standby - but if that node is
promoted all still existing files can get archived again. With a high
wal_keep_segment settings that can happen a significant time later -
which is quite confusing.
Change both the backend (for the -x/-X fetch case) and pg_basebackup
(for -X stream) itself to always mark WAL/timeline files included in
the base backup as .done. That's in line with walreceiver.c doing so.
The verbosity of the pg_basebackup changes show pretty clearly that it
needs some refactoring, but that'd result in not be backpatchable
changes.
Backpatch to 9.1 where pg_basebackup was introduced.
Discussion: 20141205002854.GE21964@awork2.anarazel.de
In pg_receivexlog, in order to check whether the current WAL file is
being opened or not, its file descriptor has to be checked against -1
as an invalid value. But, oops, 7900e94 added the incorrect test
checking the descriptor against 1. This commit fixes that bug.
Back-patch to 9.4 where the bug was added.
Spotted by Magnus Hagander
When pg_receivexlog --slot is connecting to the server, at the shutdown
of the server, walsender keeps waiting for the last WAL record to be
replicated and flushed in pg_receivexlog. But previously pg_receivexlog
issued sync command only when WAL file was switched. So there was
the case where the last WAL was never flushed and walsender had to
keep waiting infinitely. This caused the server shutdown to get stuck.
pg_recvlogical handles this problem by calling fsync() when it receives
the request of immediate reply from the server. That is, at shutdown,
walsender sends the request, pg_recvlogical receives it, flushes the last
WAL record, and sends the flush location back to the server. Since
walsender can see that the last WAL record is successfully flushed, it can
exit cleanly.
This commit introduces the same logic as pg_recvlogical has,
to pg_receivexlog.
Back-patch to 9.4 where pg_receivexlog was changed so that it can use
the replication slot.
Original patch by Michael Paquier, rewritten by me.
Bug report by Furuya Osamu.
Previously pg_receivexlog flushed WAL data only when WAL file was switched.
Then 3dad73e added -F option to pg_receivexlog so that users could control
how frequently sync commands were issued to WAL files. It also allowed users
to make pg_receivexlog flush WAL data immediately after writing by
specifying 0 in -F option. However feedback messages were not sent back
immediately even after a flush location was updated. So even if WAL data
was flushed in real time, the server could not see that for a while.
This commit removes -F option from and adds --synchronous to pg_receivexlog.
If --synchronous is specified, like the standby's wal receiver, pg_receivexlog
flushes WAL data as soon as there is WAL data which has not been flushed yet.
Then it sends back the feedback message identifying the latest flush location
to the server. This option is useful to make pg_receivexlog behave as sync
standby by using replication slot, for example.
Original patch by Furuya Osamu, heavily rewritten by me.
Reviewed by Heikki Linnakangas, Alvaro Herrera and Sawada Masahiko.
Work around accidental test failures because the working directory path
is too long by creating a temporary directory in the (hopefully shorter)
system location, symlinking that to the working directory, and creating
the tablespaces using the shorter path.
Previously pg_receivexlog created new connection for WAL streaming
even though another connection which had been established to create
or delete the replication slot was being left. This caused the unused
connection to be left uselessly until pg_receivexlog exited.
This bug was introduced by the commit d9f38c7.
This patch changes pg_receivexlog so that the connection for
the replication slot is reused for WAL streaming.
Andres Freund, slightly modified by me, reviewed by Michael Paquier
List the actions first, as they are the most important options. Group
the other options more sensibly, consistent with the man page. Correct
a few typographical errors, clarify some things.
Also update the pg_receivexlog --help output to make it a bit more
consistent with that of pg_recvlogical.
CreateReplicationSlot() and DropReplicationSlot() were not cleaning up
the query buffer in some cases (mostly error conditions) which meant a
small leak. Not generally an issue as the error case would result in an
immediate exit, but not difficult to fix either and reduces the number
of false positives from code analyzers.
In passing, also add appropriate PQclear() calls to RunIdentifySystem().
Pointed out by Coverity.
pg_receivexlog already has the capability to use a replication slot to
reserve WAL on the upstream node. But the used slot currently has to
be created via SQL.
To allow using slots directly, without involving SQL, add
--create-slot and --drop-slot actions, analogous to the logical slot
manipulation support in pg_recvlogical.
Author: Michael Paquier
Discussion: CABUevEx+zrOHZOQg+dPapNPFRJdsk59b=TSVf30Z71GnFXhQaw@mail.gmail.com
A future patch (9.5 only) adds slot management to pg_receivexlog. The
verbs create/drop don't seem descriptive enough there. It seems better
to rename pg_recvlogical's commands now, in beta, than live with the
inconsistency forever.
The old form (e.g. --drop) will still be accepted by virtue of most
getopt_long() options accepting abbreviations for long commands.
Backpatch to 9.4 where pg_recvlogical was introduced.
Author: Michael Paquier and Andres Freund
Discussion: CAB7nPqQtt79U6FmhwvgqJmNyWcVCbbV-nS72j_jyPEopERg9rg@mail.gmail.com
Move some more code to manage replication connection command to
streamutil.c. A later patch will introduce replication slot via
pg_receivexlog and this avoid duplicating relevant code between
pg_receivexlog and pg_recvlogical.
Author: Michael Paquier, with some editing by me.
Several comments still referred to 'initiating', 'freeing', 'stopping'
replication slots. These were terms used during different phases of
the development of logical decoding, but are no long accurate.
Also rename StreamLog() to StreamLogicalLog() and add 'void' to the
prototype.
Author: Michael Paquier, with some editing by me.
Backpatch to 9.4 where pg_recvlogical was introduced.
Previously, we would first create the symlinks the way they are in the
original system, and at the end replace them with the mapped symlinks.
That never really made much sense, so now we create the symlink pointing
to the correct location to begin with, so that there's no need to fix
them at the end.
The old coding didn't work correctly on Windows, because Windows junction
points look more like directories than files, and ought to be removed with
rmdir rather than unlink. Also, it incorrectly used "%d" rather than "%u"
to print an Oid, but that's gone now.
Report and patch by Amit Kapila, with minor changes by me. Reviewed by
MauMau. Backpatch to 9.4, where the --tablespace feature was added.
This reverts commit 083d29c65b.
The commit changed the code so that it causes an errors when
IDENTIFY_SYSTEM returns three columns. But which prevents us
from using the replication-related utilities against the server
with older version. This is not what we want. For that
compatibility, we allow the utilities to receive three columns
as the result of IDENTIFY_SYSTEM eventhough it actually returns
four columns in 9.4 or later.
Pointed out by Andres Freund.
5a991ef869 added new column into
the result of IDENTIFY_SYSTEM command. But it was not reflected into
several codes checking that result. Specifically though the number of
columns in the result was increased to 4, it was still compared with 3
in some replication codes.
Back-patch to 9.4 where the number of columns in IDENTIFY_SYSTEM
result was increased.
Report from Michael Paquier
This option is equivalent to --slot option which pg_receivexlog has
already supported, which specifies the replication slot to use for
WAL streaming. pg_recvlogical has already supported both options,
and this commit makes pg_receivexlog consistent with pg_recvlogical
regarding the slot option.
Back-patch to 9.4 where the slot option was added.
Michael Paquier
Some error messages complained about --init and --stop being used
whereas the --create and --drop are the correct verbs. Fix that.
Also a XLogRecPtr was tested in a boolean fashion instead of being
compared to InvalidXLogRecPtr.
Backpatch to 9.4 where pg_recvlogical was introduced.
Michael Paquier
This allows us to specify the maximum time to issue fsync to ensure
the received WAL file is safely flushed to disk. Without this,
pg_receivexlog always flushes WAL file only when it's closed and
which can cause WAL data to be lost at the event of a crash.
Furuya Osamu, heavily modified by me.
Previously the source codes for processing the received data and handling
the end of stream were included in pg_receivexlog main loop. This commit
splits out them as separate functions. This is useful for improving the
readability of main loop code and making the future pg_receivexlog-related
patch simpler.
In 9.2, pg_receivexlog with verbose option has emitted the messages
at the end of each WAL file. But the commit 0b63291 suppressed such
messages by mistake. This commit fixes the bug so that pg_receivexlog
--verbose outputs such messages again.
Back-patch to 9.3 where the bug was added.
The problem is that pg_receivexlog calls select(2) with timeout=0 and
goes into busy loop when --status-interval option is set to 0. This bug
was introduced by the commit,
74cbe966fe.
Per report from Sawada Masahiko
Prominent binaries already had this metadata. A handful of minor
binaries, such as pg_regress.exe, still lack it; efforts to eliminate
such exceptions are welcome.
Michael Paquier, reviewed by MauMau.
Previously the source codes for receiving the data and for
polling the socket were included in pg_receivexlog main loop.
This commit splits out them as separate functions. This is
useful for improving the readability of main loop code and
making the future pg_receivexlog-related patch simpler.
Previously there's been a mix between 'slotname' and 'slot_name'. It's
not nice to be unneccessarily inconsistent in a new feature. As a post
beta1 initdb now is required in the wake of eeca4cd35e, fix the
inconsistencies.
Most the changes won't affect usage of replication slots because the
majority of changes is around function parameter names. The prominent
exception to that is that the recovery.conf parameter
'primary_slotname' is now named 'primary_slot_name'.
The bug was caused by omitting 'I:' from the short argument list to
getopt_long(). To make similar bugs in the future less likely reorder
options in --help, long and short option lists to be in the same,
alphabetical within groups, order.
Report and fix by Michael Paquier, some additional reordering by me.
Let's complain about e.g an invalid path or permission problem sooner rather
than later. Before this patch, we would only try to open the output file
after receiving the first decoded message from the server.
Don't close stdout on SIGHUP. Also, when a SIGHUP is received, close the
file immediately, rather than only after receiving some more data from
the server. Rename a variable, to avoid mentally dealing with double
negatives (not unsynced means synced).
The leak is fairly small and rare, but a leak nevertheless.
Per Coverity report. Backpatch to 9.2, where pg_receivexlog was added.
pg_basebackup shares the code, but it always exits on error, so there is
no real leak.
Commit d298b50a3b by Heikki Linnakangas
requested that the version check message be updated at next release, suggesting
that the appropriate text would be “9.3 or later”. The logic used for the check
indicates that the correct text for 9.4 is “9.3 or 9.4”, since the logic would
cause this to fail for later releases.
Commit 7d0f493f19 added infrastructure
to perform tests in assorted src/bin/ subdirectories, but forgot to
teach "make clean" to clean up the detritus the tests leave behind.
Clear errno before calling readdir() and handle old MinGW errno bug
while adding full test coverage for readdir/closedir failures.
Backpatch through 8.4.
In order for this to work, walsenders need the optional ability to
connect to a database, so the "replication" keyword now allows true
or false, for backward-compatibility, and the new value "database"
(which causes the "dbname" parameter to be respected).
walsender needs to loop not only when idle but also when sending
decoded data to the user and when waiting for more xlog data to decode.
This means that there are now three separate loops inside walsender.c;
although some refactoring has been done here, this is still a bit ugly.
Andres Freund, with contributions from Álvaro Herrera, and further
review by me.
A new MAX_RATE option allows imposing a limit to the network transfer
rate from the server side. This is useful to limit the stress that
taking a base backup has on the server.
pg_basebackup is now able to specify a value to the server, too.
Author: Antonin Houska
Patch reviewed by Stefan Radomski, Andres Freund, Zoltán Böszörményi,
Fujii Masao, and Álvaro Herrera.
Tablespaces can be relocated in plain backup mode by specifying one or
more -T olddir=newdir options.
Author: Steeve Lennmark <steevel@handeldsbanken.se>
Reviewed-by: Peter Eisentraut <peter_e@gmx.net>
Coverity identified a number of places in which it couldn't prove that a
string being copied into a fixed-size buffer would fit. We believe that
most, perhaps all of these are in fact safe, or are copying data that is
coming from a trusted source so that any overrun is not really a security
issue. Nonetheless it seems prudent to forestall any risk by using
strlcpy() and similar functions.
Fixes by Peter Eisentraut and Jozef Mlich based on Coverity reports.
In addition, fix a potential null-pointer-dereference crash in
contrib/chkpass. The crypt(3) function is defined to return NULL on
failure, but chkpass.c didn't check for that before using the result.
The main practical case in which this could be an issue is if libc is
configured to refuse to execute unapproved hashing algorithms (e.g.,
"FIPS mode"). This ideally should've been a separate commit, but
since it touches code adjacent to one of the buffer overrun changes,
I included it in this commit to avoid last-minute merge issues.
This issue was reported by Honza Horak.
Security: CVE-2014-0065 for buffer overruns, CVE-2014-0066 for crypt()
If an error occurs in the foreground (backup) process of pg_basebackup,
and we exit in a controlled way, the background process (streaming
xlog process) would stay around and keep streaming.
This prevents pg_basebackup from generating excessive output when
dumping large clusters. The status is now updated once / second,
still making it possible to see that there is progress happening,
but limiting the total bandwidth.
Mika Eloranta, reviewed by Sawada Masahiko and Oskari Saarenmaa
When using verbose mode for pg_basebackup, in tar format sent to
stdout, we'd print an unitialized buffer as the filename.
Reported by Pontus Lundkvist
Replication slots are a crash-safe data structure which can be created
on either a master or a standby to prevent premature removal of
write-ahead log segments needed by a standby, as well as (with
hot_standby_feedback=on) pruning of tuples whose removal would cause
replication conflicts. Slots have some advantages over existing
techniques, as explained in the documentation.
In a few places, we refer to the type of replication slots introduced
by this patch as "physical" slots, because forthcoming patches for
logical decoding will also have slots, but with somewhat different
properties.
Andres Freund and Robert Haas
The previous coding was fairly unreadable and drew double-free warnings
from clang. I believe the double free was actually not reachable, because
PQconnectionNeedsPassword is coded to not return true if a password was
provided, so that the loop can't iterate more than twice. Nonetheless
it seems worth rewriting. No back-patch since this is just cosmetic.
This is a similar fix as c6ec8793aa
9.2. This should never happen in 9.3 and newer since the special case
cannot happen there, but this patch synchronizes up the code so there
is no confusion on why they're different. An empty block is as harmless
in 9.3 as it was in 9.2, and can safely be ignored.
The parsing of WAL filenames of segments larger than > 255 was broken,
making pg_receivexlog unable to restart streaming after stopping it.
The bug was introduced by the changes in 9.3 to represent WAL segment number
as a 64-bit integer instead of two ints, log and seg. To fix, replace the
plain sscanf call with XLogFromFileName macro, which does the conversion
from log+seg to a 64-bit integer correcly.
Reported by Mika Eloranta.
Now that msgfmt is run with -c by default, older versions of gettext are
complaining about the PO headers Last-Translator and Language-Team
still having their default values. Newer gettext versions fail to catch
this because of a bug (https://savannah.gnu.org/bugs/?40261), which is
why this hasn't been noticed before.
Copy updated versions of affected translation files from the
pgtranslations repository, were those files have been fixed.
When a timeline history file is fetched from server, it is initially created
with a temporary file name, and renamed to place. However, the temporary
file name was constructed using an uninitialized buffer. Usually that meant
that the file was created in current directory instead of the target, which
usually goes unnoticed, but if the target is on a different filesystem than
the current dir, the rename() would fail. Fix that.
The second issue is that pg_receivexlog would not take .partial files into
account when determining when scanning the target directory for existing
WAL files. If the timeline has switched in the server several times in the
last WAL segment, and pg_receivexlog is restarted, it would choose a too
old starting point. That's not a problem as long as the old WAL segment
exists in the server and can be streamed over, but will cause a failure if
it's not.
Backpatch to 9.3, where this timeline handling code was written.
Analysed by Andrew Gierth, bug #8453, based on a bug report on IRC.
In pg_basebackup.c:reached_end_position(), we're reading from an
internal pipe with our own background process but we're possibly
reading more bytes than will actually fit into our buffer due to
an off-by-one error. As we're reading from an internal pipe
there's no real risk here, but it's good form to not depend on
such convenient arrangements.
Bug spotted by the Coverity scanner.
Back-patch to 9.2 where this showed up.
In receivelog.c:writeTimeLineHistoryFile(), we were not properly
closing the open'd file descriptor in error cases. While this
wouldn't matter much if we were about to exit due to such an
error, that's not the case with pg_receivexlog as it can be a
long-running process and these errors are non-fatal.
This resource leak was found by the Coverity scanner.
Back-patch to 9.3 where this issue first appeared.
In streamutil.c:GetConnection(), upgrade failure to parse the
connection string to an exit(1) instead of simply returning NULL.
Most callers already immediately exited, but pg_receivexlog would
loop on this case, continually trying to re-parse the connection
string (which can't be changed after pg_receivexlog has started).
GetConnection() was already expected to exit(1) in some cases
(eg: failure to allocate memory or if unable to determine the
integer_datetimes flag), so this change shouldn't surprise anyone.
Began looking at this due to the Coverity scanner complaining that
we were leaking err_msg in this case- no longer an issue since we
just exit(1) immediately.
In the primary_conninfo line that "pg_basebackup -R" generates, single
quotes in parameter values need to be escaped into \\'; the libpq parser
requires the quotes to be escaped into \', and recovery.conf parser requires
the \ to be escaped into \\.
Also, don't quote parameter values unnecessarily, to make the connection
string prettier. Most options in a libpq connection string don't need
quoting.
Reported by Hari Babu, closer analysis by Zoltan Boszormenyi, although I
didn't use his patch.
If a standby server has a cascading standby server connected to it, it's
possible that WAL has already been sent up to the next WAL page boundary,
splitting a WAL record in the middle, when the first standby server is
promoted. Don't throw an assertion failure or error in walsender if that
happens.
Also, fix a variant of the same bug in pg_receivexlog: if it had already
received WAL on previous timeline up to a segment boundary, when the
upstream standby server is promoted so that the timeline switch record falls
on the previous segment, pg_receivexlog would miss the segment containing
the timeline switch. To fix that, have walsender send the position of the
timeline switch at end-of-streaming, in addition to the next timeline's ID.
It was previously assumed that the switch happened exactly where the
streaming stopped.
Note: this is an incompatible change in the streaming protocol. You might
get an error if you try to stream over timeline switches, if the client is
running 9.3beta1 and the server is more recent. It should be fine after a
reconnect, however.
Reported by Fujii Masao.
Very old versions of msgfmt choke on these specific messages, for reasons
that are unclear at the moment. Remove them so that we can ship a beta
release and not get complaints from testers (these messages will just go
untranslated, instead, and we're hardly at 100% coverage anyway).
Peter Eisentraut will look for a better fix later.
Previously, libpq and the backend had opposite ideas about whether
it was necessary for the client to send a CopyDone message after
receiving an ErrorResponse, making it impossible to cleanly exit
COPY BOTH mode. Fix libpq so that works correctly, adopting the
backend's notion that an ErrorResponse kills the copy in both
directions.
Adjust receivelog.c to avoid a degradation in the quality of the
resulting error messages. libpqwalreceiver.c is already doing
the right thing, so no adjustment needed there.
Add an explicit statement to the documentation explaining how
this part of the protocol is supposed to work, in the hopes of
avoiding future confusion in this area.
Since the consequences of all this confusion are very limited,
especially in the back-branches where no client ever attempts
to exit COPY BOTH mode without closing the connection entirely,
no back-patch.
A new 'starttli' field was added to the response of BASE_BACKUP command.
Make pg_basebackup tolerate the case that it's missing, so that it still
works with older servers.
Add an explicit check for the server version, so that you get a nicer error
message if you try to use it with a pre-9.1 server.
The streaming protocol message format changed in 9.3, so -X stream still won't
work with pre-9.3 servers. I added a version check to ReceiveXLogStream()
earlier, but write that slightly differently, so that in 9.4, it will still
work with a 9.3 server. (In 9.4, the error message needs to be adjusted to
"9.3 or above", though). Also, if the version check fails, don't retry.
We had two copies of this function in the backend and libpq, which was
already pretty bogus, but it turns out that we need it in some other
programs that don't use libpq (such as pg_test_fsync). So put it where
it probably should have been all along. The signal-mask-initialization
support in src/backend/libpq/pqsignal.c stays where it is, though, since
we only need that in the backend.
Without this, there's no way to pass arbitrary libpq connection parameters
to these applications. It's a bit strange that the option is called
-d/--dbname, when in fact you can *not* pass a database name in it, but it's
consistent with other client applications where a connection string is also
passed using -d.
Original patch by Amit Kapila, heavily modified by me.
libpgcommon is a new static library to allow sharing code among the
various frontend programs and backend; this lets us eliminate duplicate
implementations of common routines. We avoid libpgport, because that's
intended as a place for porting issues; per discussion, it seems better
to keep them separate.
The first use case, and the only implemented by this patch, is pg_malloc
and friends, which many frontend programs were already using.
At the same time, we can use this to provide palloc emulation functions
for the frontend; this way, some palloc-using files in the backend can
also be used by the frontend cleanly. To do this, we change palloc() in
the backend to be a function instead of a macro on top of
MemoryContextAlloc(). This was previously believed to cause loss of
performance, but this implementation has been tweaked by Tom and Andres
so that on modern compilers it provides a slight improvement over the
previous one.
This lets us clean up some places that were already with
localized hacks.
Most of the pg_malloc/palloc changes in this patch were authored by
Andres Freund. Zoltán Böszörményi also independently provided a form of
that. libpgcommon infrastructure was authored by Álvaro.
This mirrors the changes done earlier to the server in standby mode. When
receivelog reaches the end of a timeline, as reported by the server, it
fetches the timeline history file of the next timeline, and restarts
streaming from the new timeline by issuing a new START_STREAMING command.
When pg_receivexlog crosses a timeline, it leaves the .partial suffix on the
last segment on the old timeline. This helps you to tell apart a partial
segment left in the directory because of a timeline switch, and a completed
segment. If you just follow a single server, it won't make a difference, but
it can be significant in more complicated scenarios where new WAL is still
generated on the old timeline.
This includes two small changes to the streaming replication protocol:
First, when you reach the end of timeline while streaming, the server now
sends the TLI of the next timeline in the server's history to the client.
pg_receivexlog uses that as the next timeline, so that it doesn't need to
parse the timeline history file like a standby server does. Second, when
BASE_BACKUP command sends the begin and end WAL positions, it now also sends
the timeline IDs corresponding the positions.
When truncating at the end, like before, the output would often end up
just showing the path instead of the filename.
Also increase the length of the filename by 5, which still keeps us at
less than 80 characters in most outputs.
Adds commandline option -R to pg_basebackup that creates a recovery.conf which
enables standby mode using the same parameters that pg_basebackup used to
connect to the master, and writes it into the output directory (or injects it
in the tar file when tar format is used).
Zoltan Boszormenyi, modified by Magnus Hagander, reviewed by Amit Kapila & Fujii Masao
This gets rid of XLByteLT, XLByteLE, XLByteEQ and XLByteAdvance.
These were useful for brevity when XLogRecPtrs were split in
xlogid/xrecoff; but now that they are simple uint64's, they are just
clutter. The only downside to making this change would be ease of
backporting patches, but that has been negated by other substantive
changes to the involved code anyway. The clarity of simpler expressions
makes the change worthwhile.
Most of the changes are mechanical, but in a couple of places, the patch
author chose to invert the operator sense, making the code flow more
logical (and more in line with preceding comments).
Author: Andres Freund
Eyeballed by Dimitri Fontaine and Alvaro Herrera
Without this, the connection will be killed after timeout if
wal_sender_timeout is set in the server.
Original patch by Amit Kapila, modified by me to fit recent changes in the
code.
We used to send structs wrapped in CopyData messages, which works as long as
the client and server agree on things like endianess, timestamp format and
alignment. That's good enough for running a standby server, which has to run
on the same platform anyway, but it's useful for tools like pg_receivexlog
to work across platforms.
This breaks protocol compatibility of streaming replication, but we never
promised that to be compatible across versions, anyway.
On some platforms these functions return NULL, rather than the more common
practice of returning a pointer to a zero-sized block of memory. Hack our
various wrapper functions to hide the difference by substituting a size
request of 1. This is probably not so important for the callers, who
should never touch the block anyway if they asked for size 0 --- but it's
important for the wrapper functions themselves, which mistakenly treated
the NULL result as an out-of-memory failure. This broke at least pg_dump
for the case of no user-defined aggregates, as per report from
Matthew Carrington.
Back-patch to 9.2 to fix the pg_dump issue. Given the lack of previous
complaints, it seems likely that there is no live bug in previous releases,
even though some of these functions were in place before that.
We had a number of variants on the theme of "malloc or die", with the
majority named like "pg_malloc", but by no means all. Standardize on the
names pg_malloc, pg_malloc0, pg_realloc, pg_strdup. Get rid of pg_calloc
entirely in favor of using pg_malloc0.
This is an essentially cosmetic change, so no back-patch. (I did find
a couple of places where psql and pg_dump were using plain malloc or
strdup instead of the pg_ versions, but they don't look significant
enough to bother back-patching.)
timeval.t_sec is of type time_t, which is not always compatible with long.
I'm not sure if this was just harmless warning or a real bug, but this
fixes it, anyway.
In particular, with a controlled shutdown of the master, pg_basebackup
with streaming log could terminate without an error message, even though
the backup is not consistent.
In passing, fix a few cases where walfile wasn't properly set to -1 after
closing.
Fujii Masao
The most user-visible part of this is to change the long options
--statusint and --noloop to --status-interval and --no-loop,
respectively, per discussion.
Also, consistently enclose file names in double quotes, per our
conventions; and consistently use the term "transaction log file" to
talk about WAL segments. (Someday we may need to go over this
terminology and make it consistent across the whole source code.)
Finally, reflow the code to better fit in 80 columns, and have pgindent
fix it up some more.
The Solaris Studio compiler warns about these instances, unlike more
mainstream compilers such as gcc. But manual inspection showed that
the code is clearly not reachable, and we hope no worthy compiler will
complain about removing this code.
When the internal loop mode was added, freeing memory and closing
filedescriptors before returning became important, and a few cases
in the code missed that.
Fujii Masao
This makes it possible for the master to track how much data has
actually been written my pg_receivexlog - and not just how much
has been sent towards it.
This simplifies code that needs to do arithmetic on XLogRecPtrs.
To avoid changing on-disk format of data pages, the LSN on data pages is
still stored in the old format. That should keep pg_upgrade happy. However,
we have XLogRecPtrs embedded in the control file, and in the structs that
are sent over the replication protocol, so this changes breaks compatibility
of pg_basebackup and server. I didn't do anything about this in this patch,
per discussion on -hackers, the right thing to do would to be to change the
replication protocol to be architecture-independent, so that you could use
a newer version of pg_receivexlog, for example, against an older server
version.
The comments claimed that wasting the last segment made it easier to do
calculations with XLogRecPtrs, because you don't have problems representing
last-byte-position-plus-1 that way. In my experience, however, it only made
things more complicated, because the there was two ways to represent the
boundary at the beginning of a logical log file: logid = n+1 and xrecoff = 0,
or as xlogid = n and xrecoff = 4GB - XLOG_SEG_SIZE. Some functions were
picky about which representation was used.
Also, use a 64-bit segment number instead of the log/seg combination, to
point to a certain WAL segment. We assume that all platforms have a working
64-bit integer type nowadays.
This is an incompatible change in WAL format, so bumping WAL version number.
Before, some places didn't document the short options (-? and -V),
some documented both, some documented nothing, and they were listed in
various orders. Now this is hopefully more consistent and complete.
getopt_long() allows abbreviating long options, so we might as well
give the option the full name, and users can abbreviate it how they
like.
Do some general polishing of the --help output at the same time.
To replace it, add -X/--xlog-method that allows the specification
of fetch or stream.
Do this to avoid unnecessary backwards-incompatiblity. Spotted and
suggested by Peter Eisentraut.
Since the replication protocol deals with TimestampTz, we need to
care for the floating point case as well in the frontend tools.
Fujii Masao, with changes from Magnus Hagander
When backing up from a standby server, the backup process
will not automatically switch xlog segment. So we must
accept a partially transferred xlog file in this case, but
rename it into position anyway.
In passing, merge the two callbacks for segment end and
stop stream into a single callback, since their implementations
were close to identical, and rename this callback to
reflect that it stops streaming rather than continues it.
Patch by Magnus Hagander, review by Fujii Masao
Some of these are newly added, some are older and were forgotten, some
don't contain any translatable strings right now but look like they
could in the future.
gzFile is already a pointer, so code like
gzFile *handle = gzopen(...)
is wrong.
This used to pass silently because gzFile used to be defined as void*,
and you can assign a void* to a void**. But somewhere between zlib
versions 1.2.3.4 and 1.2.6, the definition of gzFile was changed to
struct gzFile_s *, and with that new definition this usage causes
compiler warnings.
So remove all those extra pointer decorations.
There is a related issue in pg_backup_archiver.h, where
FILE *FH; /* General purpose file handle */
is used throughout pg_dump as sometimes a real FILE* and sometimes a
gzFile handle, which also causes warnings now. This is not yet fixed
here, because it might need more code restructuring.
Teach pg_basebackup in streaming mode to deal with keepalive messages.
Also change the order of checks to complain at the message rather than
block size when a new message is introduced.
In passing, switch to using sizeof() instead of hardcoded sizes for
WAL protocol structs.
Instead of filling files as they appear, pre-pad the
WAL files received when streaming xlog the same way
that the server does. Data is streamed into a .partial
file which is then renamed()d into palce when it's complete,
but it will always be 16MB.
This also means that the starting position for pg_receivexlog
is now simply right after the last complete segment, and we
never need to deal with partial segments there.
Patch by me, review by Fujii Masao
Add option for parallel streaming of the transaction log while a
base backup is running, to get the logfiles before the server has
removed them.
Also add a tool called pg_receivexlog, which streams the transaction
log into files, creating a log archive without having to wait for
segments to complete, thus decreasing the window of data loss without
having to waste space using archive_timeout. This works best in
combination with archive_command - suggested usage docs etc coming later.
When streaming including WAL, the size estimate will always be incorrect,
since we don't know how much WAL is included. To make sure the output doesn't
look completely unreasonable, this patch increases the total size whenever we
go past the estimate, to make sure we never go above 100%.
It currently doesn't make a difference, but it's inconsistent with
most other usage, and it might interfere with a future patch, so I'll
change it all in a separate commit.
Also, replace tabs with spaces for alignment.
The short-form -z switch didn't work, for lack of telling getopt_long
about it; and even if specified long-form, it failed to do anything,
because the various tests elsewhere in the file would take
Z_DEFAULT_COMPRESSION (which is -1) as meaning "don't compress".
Per bug #6060 from Shigehiro Honda, though I editorialized on his patch
a bit.
This code was accidentally part of the patch, it's only
needed for the code that's for 9.2. Not needing the timeline
also removes the need to call IDENTIFY_SYSTEM.
Noted by Peter E.
Add the current xlog insert location to the response of
IDENTIFY_SYSTEM, and adds result sets containing start
and stop location of backups to BASE_BACKUP responses.
When included, this makes the base backup a complete working
"clone" of the initial database, ready to have a postmaster
started against it without the need to set up any log archiving
or similar.
Magnus Hagander, reviewed by Fujii Masao and Heikki Linnakangas
The target of sscanf with a %o format had better be of integer width,
but "mode_t" conceivably isn't that. Another compiler warning seen
only on some platforms; this one I think is potentially a real bug
and not just a warning.
This tool makes it possible to do the pg_start_backup/
copy files/pg_stop_backup step in a single command.
There are still some steps to be done before this is a
complete backup solution, such as the ability to stream
the required WAL logs, but it's still usable, and
could do with some buildfarm coverage.
In passing, make the checkpoint request optionally
fast instead of hardcoding it.
Magnus Hagander, reviewed by Fujii Masao and Dimitri Fontaine
Alvaro Herrera
Tom Lane
Peter Eisentraut
Andres Freund
Andrew Dunstan
Heikki Linnakangas
Noah Misch
Bruce Momjian
Fujii Masao
Robert Haas
Stephen Frost
Simon Riggs
Magnus Hagander
Greg Stark