AIO will need a resource owner to do IO. Right now we create a resowner
on-demand during basebackup, and we could do the same for AIO. But it seems
easier to just always create an aux process resowner.
Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>
Reviewed-by: Noah Misch <noah@leadboat.com>
Discussion: https://postgr.es/m/1f6b50a7-38ef-4d87-8246-786d39f46ab9@iki.fi
Similarly to 2065ddf5e3, this introduces a define for "pg_tblspc".
This makes the style more consistent with the existing PG_STAT_TMP_DIR,
for example.
There is a difference with the other cases with the introduction of
PG_TBLSPC_DIR_SLASH, required in two places for recovery and backups.
Author: Bertrand Drouvot
Reviewed-by: Ashutosh Bapat, Álvaro Herrera, Yugo Nagata, Michael
Paquier
Discussion: https://postgr.es/m/ZryVvjqS9SnV1GPP@ip-10-97-1-34.eu-west-3.compute.internal
This commit replaces most of the hardcoded values of "pg_replslot" by a
new PG_REPLSLOT_DIR #define. This makes the style more consistent with
the existing PG_STAT_TMP_DIR, for example. More places will follow a
similar change.
Author: Bertrand Drouvot
Reviewed-by: Ashutosh Bapat, Yugo Nagata, Michael Paquier
Discussion: https://postgr.es/m/ZryVvjqS9SnV1GPP@ip-10-97-1-34.eu-west-3.compute.internal
All the errors triggered in the code paths patched here would cause the
backend to issue an internal_error errcode, which is a state that should
be used only for "can't happen" situations. However, these code paths
are reachable by the regression tests, and could be seen by users in
valid cases. Some regression tests expect internal errcodes as they
manipulate the backend state to cause corruption (like checksums), or
use elog() because it is more convenient (like injection points), these
have no need to change.
This reduces the number of internal failures triggered in a check-world
by more than half, while providing correct errcodes for these valid
cases.
Reviewed-by: Robert Haas
Discussion: https://postgr.es/m/Zic_GNgos5sMxKoa@paquier.xyz
Commit 10e3226ba1 added padding to incremental backups to ensure the
block data is properly aligned. The code in sendFile() however failed to
consider that the header may be a multiple of BLCKSZ and thus already
aligned, adding a full BLCKSZ of unnecessary padding.
Not only does this make the incremental file a bit larger, but the other
places calculating the amount of padding did realize it's not needed and
did not include it in the formula. This resulted in pg_basebackup
getting confused while parsing the data stream, trying to access files
with invalid filenames (e.g. with binary data etc.) and failing.
Align blocks stored in incremental files to BLCKSZ, so that the
incremental backups work well with CoW filesystems.
The header of the incremental file is padded with \0 to a multiple of
BLCKSZ, so that the block data (also BLCKSZ) is aligned to BLCKSZ. The
padding is added only to files containing block data, so files with just
the header remain small. This adds a bit of extra space, but as the
number of blocks increases the overhead gets negligible very quickly.
And as the padding is \0 bytes, it does compress extremely well.
The alignment is important for CoW filesystems that usually require the
blocks to be aligned to filesystem page size for features like block
sharing, deduplication etc. to work well. With the variable sized header
the blocks in the increments were not aligned at all, negating the
benefits of the CoW filesystems.
This matters even for non-CoW filesystems, for example when placed on a
RAID array. If the block is not aligned, it may easily span multiple
devices, causing read and write amplification.
It might be better to align the blocks to the filesystem page, not
BLCKSZ, but we have no good way to determine that. Even if we determine
the page size at the time of taking the backup, the backup may move. For
now the BLCKSZ seems sufficient - the filesystem page is usually 4K, so
the default BLCKSZ (8K by default) is aligned to that.
Author: Tomas Vondra
Reviewed-by: Robert Haas, Jakub Wartak
Discussion: https://postgr.es/m/3024283a-7491-4240-80d0-421575f6bb23%40enterprisedb.com
destroyStringInfo() is a counterpart to makeStringInfo(), freeing a
palloc'd StringInfo and its data. This is a convenience function to
align the StringInfo API with the PQExpBuffer API. Originally added
in the OAuth patchset, it was extracted and committed separately in
order to aid upcoming JSON work.
Author: Daniel Gustafsson <daniel@yesql.se>
Author: Jacob Champion <jacob.champion@enterprisedb.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Discussion: https://postgr.es/m/CAOYmi+mWdTd6ujtyF7MsvXvk7ToLRVG_tYAcaGbQLvf=N4KrQw@mail.gmail.com
as determined by include-what-you-use (IWYU)
While IWYU also suggests to *add* a bunch of #include's (which is its
main purpose), this patch does not do that. In some cases, a more
specific #include replaces another less specific one.
Some manual adjustments of the automatic result:
- IWYU currently doesn't know about includes that provide global
variable declarations (like -Wmissing-variable-declarations), so
those includes are being kept manually.
- All includes for port(ability) headers are being kept for now, to
play it safe.
- No changes of catalog/pg_foo.h to catalog/pg_foo_d.h, to keep the
patch from exploding in size.
Note that this patch touches just *.c files, so nothing declared in
header files changes in hidden ways.
As a small example, in src/backend/access/transam/rmgr.c, some IWYU
pragma annotations are added to handle a special case there.
Discussion: https://www.postgresql.org/message-id/flat/af837490-6b2f-46df-ba05-37ea6a6653fc%40eisentraut.org
The macOS Finder application creates .DS_Store files in directories
when opened, which creates problems for serverside utilities which
expect all files to be PostgreSQL specific files. Skip these files
when encountered in pg_checksums, pg_rewind and pg_basebackup.
This was extracted from a larger patchset for skipping hidden files
and system files, where the concencus was to just skip these. Since
this is equally likely to happen in every version, backpatch to all
supported versions.
Reported-by: Mark Guertin <markguertin@gmail.com>
Reviewed-by: Michael Paquier <michael@paquier.xyz>
Reviewed-by: Tobias Bussmann <t.bussmann@gmx.net>
Discussion: https://postgr.es/m/E258CE50-AB0E-455D-8AAD-BB4FE8F882FB@gmail.com
Backpatch-through: v12
Recently-introduced code in reconstruct.c was using "unsigned"
to store the result of read(), pg_pread(), or write(). This is
completely bogus: it breaks subsequent tests for the result being
negative, as we're being reminded of by a chorus of buildfarm
warnings. Switch to "int" as was doubtless intended. (There are
several other uses of "unsigned" in this file that also look poorly
chosen to me, but for now I'm just trying to clean up the buildfarm.)
A larger problem is that "int" is not necessarily wide enough to hold
the result: per POSIX, all these functions return ssize_t. In places
where the requested read or write length clearly fits in int, that's
academic. It may be academic anyway as long as we constrain
individual data files to 1GB, since even a readv or writev-like
operation would then not be responsible for transferring more than
1GB. Nonetheless it seems like trouble waiting to happen, so I made
a pass over readv and writev calls and fixed the result variables
where that seemed appropriate. We might want to think about changing
some of the fd.c functions to return ssize_t too, for future-proofing;
but I didn't tackle that here.
Discussion: https://postgr.es/m/1672202.1703441340@sss.pgh.pa.us
To take an incremental backup, you use the new replication command
UPLOAD_MANIFEST to upload the manifest for the prior backup. This
prior backup could either be a full backup or another incremental
backup. You then use BASE_BACKUP with the INCREMENTAL option to take
the backup. pg_basebackup now has an --incremental=PATH_TO_MANIFEST
option to trigger this behavior.
An incremental backup is like a regular full backup except that
some relation files are replaced with files with names like
INCREMENTAL.${ORIGINAL_NAME}, and the backup_label file contains
additional lines identifying it as an incremental backup. The new
pg_combinebackup tool can be used to reconstruct a data directory
from a full backup and a series of incremental backups.
Patch by me. Reviewed by Matthias van de Meent, Dilip Kumar, Jakub
Wartak, Peter Eisentraut, and Álvaro Herrera. Thanks especially to
Jakub for incredibly helpful and extensive testing.
Discussion: http://postgr.es/m/CA+TgmoYOYZfMCyOXFyC-P+-mdrZqm5pP2N7S-r0z3_402h9rsA@mail.gmail.com
Previously, it thought that any plain file located under global, base,
or a tablespace directory had checksums unless it was in a short list
of excluded files. Now, it thinks that files in those directories have
checksums if parse_filename_for_nontemp_relation says that they are
relation files. (Temporary relation files don't matter because they're
excluded from the backup anyway.)
This changes the behavior if you have stray files not managed by
PostgreSQL in the relevant directories. Previously, you'd get some
kind of checksum-related complaint if such files existed, assuming
that the cluster had checksums enabled and that the base backup
wasn't run with NOVERIFY_CHECKSUMS. Now, you won't get those
complaints any more. That seems like an improvement to me, because
those files were presumably not created by PostgreSQL and so there
is no reason to think that they would be checksummed like a
PostgreSQL relation file. (If we want to complain about such files,
we should complain about them existing at all, not just about their
checksums.)
The point of this change is to make the code more consistent.
sendDir() was already calling parse_filename_for_nontemp_relation()
as part of an effort to determine which files to include in the
backup. So, it already had the information about whether a certain
file was a relation file. sendFile() then used a separate method,
embodied in is_checksummed_file(), to make what is essentially
the same determination. It's better not to make the same decision
using two different methods, especially in closely-related code.
Patch by me. Reviewed by Dilip Kumar and Álvaro Herrera. Thanks
also to Jakub Wartak and Peter Eisentraut for comments, suggestions,
and testing on the larger patch set of which this is a part.
Discussion: http://postgr.es/m/CAFiTN-snhaKkWhi2Gz5i3cZeKefun6sYL==wBoqqnTXxX4_mFA@mail.gmail.com
Discussion: http://postgr.es/m/202311141312.u4qx5gtpvfq3@alvherre.pgsql
sendFileWithContent() previously got the content length by using
strlen(), assuming that the content given is always a string. Some
patches are under discussion to pass binary contents to a base backup
stream, where an arbitrary length needs to be given by the caller
instead.
The patch extends sendFileWithContent() to be able to handle this case,
where len < 0 can be used to indicate an arbitrary length rather than
rely on strlen() for the content length.
A comment in sendFileWithContent() mentioned the backup_label file.
However, this routine is used by more file types, like the tablespace
map, so adjust it in passing.
Author: David Steele
Discussion: https://postgr.es/m/2daf8adc-8db7-4204-a7f2-a7e94e2bfa4b@pgmasters.net
This shouldn't change behavior except in the unusual case where
there are file in the tablespace directory that have entirely
numeric names but are nevertheless not possible names for a
tablespace directory, either because their names have leading zeroes
that shouldn't be there, or the value is actually zero, or because
the value is too large to represent as an OID.
In those cases, the directory would previously have made it into
the list of tablespaceinfo objects and no longer will. Thus, base
backups will now ignore such directories, instead of treating them
as legitimate tablespace directories. Similarly, if entries for
such tablespaces occur in a tablespace_map file, they will now
be rejected as erroneous, instead of being honored.
This is infrastructure for future work that wants to be able to
know the tablespace of each relation that is part of a backup
*as an OID*. By strengthening the up-front validation, we don't
have to worry about weird cases later, and can more easily avoid
repeated string->integer conversions.
Patch by me, reviewed by David Steele.
Discussion: http://postgr.es/m/CA+TgmoZNVeBzoqDL8xvr-nkaepq815jtDR4nJzPew7=3iEuM1g@mail.gmail.com
Instead of returning the number of characters in the RelFileNumber,
return the RelFileNumber itself. Continue to return the fork number,
as before, and additionally return the segment number.
parse_filename_for_nontemp_relation now rejects a RelFileNumber or
segment number that begins with a leading zero. Before, we accepted
such cases as relation filenames, but if we continued to do so after
this change, the function might return the same values for two
different files (e.g. 1234.5 and 001234.5 or 1234.005) which could be
annoying for callers. Since we don't actually ever generate filenames
with leading zeroes in the names, any such files that we find must
have been created by something other than PostgreSQL, and it is
therefore reasonable to treat them as non-relation files.
Along the way, change unlogged_relation_entry to store a RelFileNumber
rather than an OID. This update should have been made in
851f4cc75c, but it was overlooked.
It's trivial to make the update as part of this commit, perhaps more
trivial than it would have been without it, so do that.
Patch by me, reviewed by David Steele.
Discussion: http://postgr.es/m/CA+TgmoZNVeBzoqDL8xvr-nkaepq815jtDR4nJzPew7=3iEuM1g@mail.gmail.com
This further reduces the length and complexity of sendFile(),
hopefully make it easier to understand and modify. In addition
to moving some logic into a new function, I took this opportunity
to make a few slight adjustments to sendFile() itself, including
renaming the 'len' variable to 'bytes_done', since we use it to represent
the number of bytes we've already handled so far, not the total
length of the file.
Patch by me, reviewed by David Steele.
Discussion: http://postgr.es/m/CA+TgmoYt5jXH4U6cu1dm9Oe2FTn1aae6hBNhZzJJjyjbE_zYig@mail.gmail.com
If checksum verification fails for a particular page, we reread the
page and try one more time. The code that does this somewhat complex
and difficult to follow. Move some of the logic into a new function
and rearrange the code a bit to try to make it clearer. This way,
we don't need the block_retry Boolean, a couple of other variables
move from sendFile() into the new function, and some code is now less
deeply indented.
Patch by me, reviewed by David Steele.
Discussion: http://postgr.es/m/CA+TgmoYt5jXH4U6cu1dm9Oe2FTn1aae6hBNhZzJJjyjbE_zYig@mail.gmail.com
Presently, frontend code that needs to use these macros must either
include storage/fd.h, which declares several frontend-unsafe
functions, or duplicate the macros. This commit moves these macros
to common/file_utils.h, which is safe for both frontend and backend
code. Consequently, we can also remove the duplicated macros in
pg_checksums and stop including storage/fd.h in pg_rewind.
Reviewed-by: Michael Paquier
Discussion: https://postgr.es/m/ZOP5qoUualu5xl2Z%40paquier.xyz
Run pgindent, pgperltidy, and reformat-dat-files.
This set of diffs is a bit larger than typical. We've updated to
pg_bsd_indent 2.1.2, which properly indents variable declarations that
have multi-line initialization expressions (the continuation lines are
now indented one tab stop). We've also updated to perltidy version
20230309 and changed some of its settings, which reduces its desire to
add whitespace to lines to make assignments etc. line up. Going
forward, that should make for fewer random-seeming changes to existing
code.
Discussion: https://postgr.es/m/20230428092545.qfb3y5wcu4cm75ur@alvherre.pgsql
This fixes many spelling mistakes in comments, but a few references to
invalid parameter names, function names and option names too in comments
and also some in string constants
Also, fix an #undef that was undefining the incorrect definition
Author: Alexander Lakhin
Reviewed-by: Justin Pryzby
Discussion: https://postgr.es/m/d5f68d19-c0fc-91a9-118d-7c6a5a3f5fad@gmail.com
The functions that follow are concerned with various things, of
which the tar format is only one, so this comment doesn't really
seem helpful. The file isn't really divided into sections in the
way that this comment seems to contemplate -- or at least, not
any more.
Patch by me, reviewed by Michael Paquier.
Discussion: http://postgr.es/m/CA+TgmoZ_fFAoU6mrHt9QBs+dcYhN6yXenGTTMRebZNhtwPwHyg@mail.gmail.com
We read blocks of data from files that we're backing up in chunks,
some multiple of BLCKSZ for each read. If checksum verification fails,
we then try rereading just the one block for which validation failed.
If that block happened to be the first block of the chunk, and if
the file was concurrently truncated to remove that block, then we'd
reach a call to bbsink_archive_contents() with a buffer length of 0.
That causes an assertion failure.
As far as I can see, there are no particularly bad consequences if
this happens in a non-assert build, and it's pretty unlikely to happen
in the first place because it requires a series of somewhat unlikely
things to happen in very quick succession. However, assertion failures
are bad, so rearrange the code to avoid that possibility.
Patch by me, reviewed by Michael Paquier.
Discussion: http://postgr.es/m/CA+TgmoZ_fFAoU6mrHt9QBs+dcYhN6yXenGTTMRebZNhtwPwHyg@mail.gmail.com
Because we added StaticAssertStmt() first before StaticAssertDecl(),
some uses as well as the instructions in c.h are now a bit backwards
from the "native" way static assertions are meant to be used in C.
This updates the guidance and moves some static assertions to better
places.
Specifically, since the addition of StaticAssertDecl(), we can put
static assertions at the file level. This moves a number of static
assertions out of function bodies, where they might have been stuck
out of necessity, to perhaps better places at the file level or in
header files.
Also, when the static assertion appears in a position where a
declaration is allowed, then using StaticAssertDecl() is more native
than StaticAssertStmt().
Reviewed-by: John Naylor <john.naylor@enterprisedb.com>
Discussion: https://www.postgresql.org/message-id/flat/941a04e7-dd6f-c0e4-8cdf-a33b3338cbda%40enterprisedb.com
If sendFileWithContent were used to send a file larger than the
bbsink buffer size, this would result in corruption. The only
files that are sent via sendFileWithContent are the backup label
file, the tablespace map file, and .done files for WAL segments
included in the backup. Of these, it seems that only the
tablespace_map file can become large enough to cause a problem,
and then only if you have a lot of tablespaces. If you do have
that situation, you might end up with a corrupted
tablespace_map file, which would be bad.
My commit bef47ff85d introduced
this problem.
Report and patch by Antonin Houska.
Discussion: http://postgr.es/m/15764.1670528645@antos
In a similar effort to f01592f91, here we mostly rename shadowed local
variables to remove the warnings produced when compiling with
-Wshadow=compatible-local.
This fixes 63 warnings and leaves just 5.
Author: Justin Pryzby, David Rowley
Reviewed-by: Justin Pryzby
Discussion https://postgr.es/m/20220817145434.GC26426%40telsasoft.com
Commits cf112c12 and a0dc8271 were a little too hasty in getting rid of
the pg_ prefixes where we use pread(), pwrite() and vectored variants.
We dropped support for ancient Unixes where we needed to use lseek() to
implement replacements for those, but it turns out that Windows also
changes the current position even when you pass in an offset to
ReadFile() and WriteFile() if the file handle is synchronous, despite
its documentation saying otherwise.
Switching to asynchronous file handles would fix that, but have other
complications. For now let's just put back the pg_ prefix and add some
comments to highlight the non-standard side-effect, which we can now
describe as Windows-only.
Reported-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Reviewed-by: Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>
Discussion: https://postgr.es/m/20220923202439.GA1156054%40nathanxps13
There are still some alignment-related failures in the buildfarm,
which might or might not be able to be fixed quickly, but I've also
just realized that it increased the size of many WAL records by 4 bytes
because a block reference contains a RelFileLocator. The effect of that
hasn't been studied or discussed, so revert for now.
RelFileNumbers are now assigned using a separate counter, instead of
being assigned from the OID counter. This counter never wraps around:
if all 2^56 possible RelFileNumbers are used, an internal error
occurs. As the cluster is limited to 2^64 total bytes of WAL, this
limitation should not cause a problem in practice.
If the counter were 64 bits wide rather than 56 bits wide, we would
need to increase the width of the BufferTag, which might adversely
impact buffer lookup performance. Also, this lets us use bigint for
pg_class.relfilenode and other places where these values are exposed
at the SQL level without worrying about overflow.
This should remove the need to keep "tombstone" files around until
the next checkpoint when relations are removed. We do that to keep
RelFileNumbers from being recycled, but now that won't happen
anyway. However, this patch doesn't actually change anything in
this area; it just makes it possible for a future patch to do so.
Dilip Kumar, based on an idea from Andres Freund, who also reviewed
some earlier versions of the patch. Further review and some
wordsmithing by me. Also reviewed at various points by Ashutosh
Sharma, Vignesh C, Amul Sul, Álvaro Herrera, and Tom Lane.
Discussion: http://postgr.es/m/CA+Tgmobp7+7kmi4gkq7Y+4AM9fTvL+O1oQ4-5gFTT+6Ng-dQ=g@mail.gmail.com
This was used as the returned result type of the generated contents for
the backup_label and backup history files. This is replaced by a simple
string, reducing the cleanup burden of all the callers of
build_backup_content().
Reviewed-by: Bharath Rupireddy
Discussion: https://postgr.es/m/YzERvNPaZivHEKZJ@paquier.xyz
This change simplifies some of the logic related to the generation and
creation of the backup_label and backup history files, which has become
unnecessarily complicated since the removal of the exclusive backup mode
in commit 39969e2. The code was previously generating the contents of
these files as a string (start phase for the backup_label and stop phase
for the backup history file), one problem being that the contents of the
backup_label string were scanned to grab some of its internal contents
at the stop phase.
This commit changes the logic so as we store the data required to build
these files in an intermediate structure named BackupState. The
backup_label file and backup history file strings are generated when
they are ready to be sent back to the client. Both files are now
generated with the same code path. While on it, this commit renames
some variables for clarity.
Two new files named xlogbackup.{c,h} are introduced in this commit, to
remove from xlog.c some of the logic around base backups. Note that
more could be moved to this new set of files.
Author: Bharath Rupireddy, Michael Paquier
Reviewed-by: Fujii Masao
Discussion: https://postgr.es/m/CALj2ACXWwTDgJqCjdaPyfR7djwm6SrybGcrZyrvojzcsmt4FFw@mail.gmail.com
Make sure that function declarations use names that exactly match the
corresponding names from function definitions in optimizer, parser,
utility, libpq, and "commands" code, as well as in remaining library
code. Do the same for all code related to frontend programs (with the
exception of pg_dump/pg_dumpall related code).
Like other recent commits that cleaned up function parameter names, this
commit was written with help from clang-tidy. Later commits will handle
ecpg and pg_dump/pg_dumpall.
Author: Peter Geoghegan <pg@bowt.ie>
Reviewed-By: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/CAH2-WznJt9CMM9KJTMjJh_zbL5hD9oX44qdJ4aqZtjFi-zA3Tg@mail.gmail.com
guc.c has grown to be one of our largest .c files, making it
a bottleneck for compilation. It's also acquired a bunch of
knowledge that'd be better kept elsewhere, because of our not
very good habit of putting variable-specific check hooks here.
Hence, split it up along these lines:
* guc.c itself retains just the core GUC housekeeping mechanisms.
* New file guc_funcs.c contains the SET/SHOW interfaces and some
SQL-accessible functions for GUC manipulation.
* New file guc_tables.c contains the data arrays that define the
built-in GUC variables, along with some already-exported constant
tables.
* GUC check/assign/show hook functions are moved to the variable's
home module, whenever that's clearly identifiable. A few hard-
to-classify hooks ended up in commands/variable.c, which was
already a home for miscellaneous GUC hook functions.
To avoid cluttering a lot more header files with #include "guc.h",
I also invented a new header file utils/guc_hooks.h and put all
the GUC hook functions' declarations there, regardless of their
originating module. That allowed removal of #include "guc.h"
from some existing headers. The fallout from that (hopefully
all caught here) demonstrates clearly why such inclusions are
best minimized: there are a lot of files that, for example,
were getting array.h at two or more levels of remove, despite
not having any connection at all to GUCs in themselves.
There is some very minor code beautification here, such as
renaming a couple of inconsistently-named hook functions
and improving some comments. But mostly this just moves
code from point A to point B and deals with the ensuing
needs for #include adjustments and exporting a few functions
that previously weren't exported.
Patch by me, per a suggestion from Andres Freund; thanks also
to Michael Paquier for the idea to invent guc_funcs.c.
Discussion: https://postgr.es/m/587607.1662836699@sss.pgh.pa.us
The comment in basebackup.c updated by 33bd4698c1 was actually
obsolete to begin with, since the symbols it was referring to haven't
existed in that header file for quite some time. The header file is
still needed for other reasons, though, so keep the #include, just
drop the comment.
Now that lstat() reports junction points with S_IFLNK/S_ISLINK(), and
unlink() can unlink them, there is no need for conditional code for
Windows in a few places. That was expressed by testing for WIN32 or
S_ISLNK, which we can now constant-fold.
The coding around pgwin32_is_junction() was a bit suspect anyway, as we
never checked for errors, and we also know that errors can be spuriously
reported because of transient sharing violations on this OS. The
lstat()-based code has handling for that.
This also reverts 4fc6b6ee on master only. That was done because
lstat() didn't previously work for symlinks (junction points), but now
it does.
Tested-by: Andrew Dunstan <andrew@dunslane.net>
Discussion: https://postgr.es/m/CA%2BhUKGLfOOeyZpm5ByVcAt7x5Pn-%3DxGRNCvgiUPVVzjFLtnY0w%40mail.gmail.com
pread() and pwrite() are in SUSv2, and all targeted Unix systems have
them.
Previously, we defined pg_pread and pg_pwrite to emulate these function
with lseek() on old Unixen. The names with a pg_ prefix were a reminder
of a portability hazard: they might change the current file position.
That hazard is gone, so we can drop the prefixes.
Since the remaining replacement code is Windows-only, move it into
src/port/win32p{read,write}.c, and move the declarations into
src/include/port/win32_port.h.
No need for vestigial HAVE_PREAD, HAVE_PWRITE macros as they were only
used for declarations in port.h which have now moved into win32_port.h.
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Greg Stark <stark@mit.edu>
Reviewed-by: Robert Haas <robertmhaas@gmail.com>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
symlink() and readlink() are in SUSv2 and all targeted Unix systems have
them. We have partial emulation on Windows. Code that raised runtime
errors on systems without it has been dead for years, so we can remove
that and also references to such systems in the documentation.
Define HAVE_READLINK and HAVE_SYMLINK macros on Unix. Our Windows
replacement functions based on junction points can't be used for
relative paths or for non-directories, so the macros can be used to
check for full symlink support. The places that deal with tablespaces
can just use symlink functions without checking the macros. (If they
did check the macros, they'd need to provide an #else branch with a
runtime or compile time error, and it'd be dead code.)
Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://postgr.es/m/CA+hUKGJ3LHeP9w5Fgzdr4G8AnEtJ=z=p6hGDEm4qYGEUX5B6fQ@mail.gmail.com
Commit b0a55e4329 missed a few places
where we are referring to the number used as a part of the relation
filename as an "OID". We now want to call that a "RelFileNumber".
Some of these places actually made it sound like the OID in question
is pg_class.oid rather than pg_class.relfilenode, which is especially
good to clean up.
Dilip Kumar with some editing by me.
Multiple non-exclusive backups are able to be run conrrently in different
sessions. But, in the same session, only one non-exclusive backup can be
run at the same moment. If pg_backup_start (pg_start_backup in v14 or before)
is called in the middle of another non-exclusive backup in the same session,
an error is thrown.
However, previously, in logical replication walsender mode, even if that
walsender session had already called pg_backup_start and started
a non-exclusive backup, it could execute BASE_BACKUP command and
start another non-exclusive backup. Which caused subsequent pg_backup_stop
to throw an error because BASE_BACKUP unexpectedly reset the session state
marked by pg_backup_start.
This commit prevents BASE_BACKUP command in the middle of another
non-exclusive backup in the same session.
Back-patch to all supported branches.
Author: Fujii Masao
Reviewed-by: Kyotaro Horiguchi, Masahiko Sawada, Michael Paquier, Robert Haas
Discussion: https://postgr.es/m/3374718f-9fbf-a950-6d66-d973e027f44c@oss.nttdata.com
pg_start_backup() and pg_stop_backup() have been respectively renamed to
pg_backup_start() and pg_backup_stop() as of 39969e2, but a few comments
did not get the call.
Reviewed-by: Kyotaro Horiguchi, David Steele
Discussion: https://postgr.es/m/YrqGlj1+4DF3dbZ/@paquier.xyz
Compression option handling (level, algorithm or even workers) can be
used across several parts of the system and not only base backups.
Structures, objects and routines are renamed in consequence, to remove
the concept of base backups from this part of the code making this
change straight-forward.
pg_receivewal, that has gained support for LZ4 since babbbb5, will make
use of this infrastructure for its set of compression options, bringing
more consistency with pg_basebackup. This cleanup needs to be done
before releasing a beta of 15. pg_dump is a potential future target, as
well, and adding more compression options to it may happen in 16~.
Author: Michael Paquier
Reviewed-by: Robert Haas, Georgios Kokolatos
Discussion: https://postgr.es/m/YlPQGNAAa04raObK@paquier.xyz
Bruce Momjian