This is a backpatch to branches 10-14 of the following commits:
7170f2159fb2 Allow "in place" tablespaces.
c6f2f01611d4 Fix pg_basebackup with in-place tablespaces.
f6f0db4d6240 Fix pg_tablespace_location() with in-place tablespaces
7a7cd84893e0 doc: Remove mention to in-place tablespaces for pg_tablespace_location()
5344723755bd Remove unnecessary Windows-specific basebackup code.
In-place tablespaces were introduced as a testing helper mechanism, but
they are going to be used for a bugfix in WAL replay to be backpatched
to all stable branches.
I (Álvaro) had to adjust some code to account for lack of
get_dirent_type() in branches prior to 14.
Author: Thomas Munro <thomas.munro@gmail.com>
Author: Michaël Paquier <michael@paquier.xyz>
Author: Álvaro Herrera <alvherre@alvh.no-ip.org>
Discussion: https://postgr.es/m/
20220722081858.omhn2in5zt3g4nek@alvherre.pgsql
</para>
<variablelist>
+ <varlistentry id="guc-allow-in-place-tablespaces" xreflabel="allow_in_place_tablespaces">
+ <term><varname>allow_in_place_tablespaces</varname> (<type>boolean</type>)
+ <indexterm>
+ <primary><varname>allow_in_place_tablespaces</varname> configuration parameter</primary>
+ </indexterm>
+ </term>
+ <listitem>
+ <para>
+ Allows tablespaces to be created as directories inside
+ <filename>pg_tblspc</filename>, when an empty location string
+ is provided to the <command>CREATE TABLESPACE</command> command. This
+ is intended to allow testing replication scenarios where primary and
+ standby servers are running on the same machine. Such directories
+ are likely to confuse backup tools that expect to find only symbolic
+ links in that location. Only superusers can change this setting.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="guc-allow-system-table-mods" xreflabel="allow_system_table_mods">
<term><varname>allow_system_table_mods</varname> (<type>boolean</type>)
<indexterm>
int rllen;
StringInfoData buflinkpath;
char *s = linkpath;
+#ifndef WIN32
+ struct stat st;
+#endif
/* Skip special stuff */
if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0)
snprintf(fullpath, sizeof(fullpath), "pg_tblspc/%s", de->d_name);
+ /*
+ * Skip anything that isn't a symlink/junction. For testing only,
+ * we sometimes use allow_in_place_tablespaces to create
+ * directories directly under pg_tblspc, which would fail below.
+ */
+#ifndef WIN32
+ if (lstat(fullpath, &st) < 0)
+ ereport(LOG,
+ (errcode_for_file_access(),
+ errmsg("could not stat file \"%s\": %m",
+ fullpath)));
+ else if (!S_ISLNK(st.st_mode))
+#else /* WIN32 */
+ if (!pgwin32_is_junction(fullpath))
+#endif
+ continue;
+
#if defined(HAVE_READLINK) || defined(WIN32)
rllen = readlink(fullpath, linkpath, sizeof(linkpath));
if (rllen < 0)
/* GUC variables */
char *default_tablespace = NULL;
char *temp_tablespaces = NULL;
+bool allow_in_place_tablespaces = false;
static void create_tablespace_directories(const char *location,
char *location;
Oid ownerId;
Datum newOptions;
+ bool in_place;
/* Must be super user */
if (!superuser())
(errcode(ERRCODE_INVALID_NAME),
errmsg("tablespace location cannot contain single quotes")));
+ in_place = allow_in_place_tablespaces && strlen(location) == 0;
+
/*
* Allowing relative paths seems risky
*
- * this also helps us ensure that location is not empty or whitespace
+ * This also helps us ensure that location is not empty or whitespace,
+ * unless specifying a developer-only in-place tablespace.
*/
- if (!is_absolute_path(location))
+ if (!in_place && !is_absolute_path(location))
ereport(ERROR,
(errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
errmsg("tablespace location must be an absolute path")));
char *linkloc;
char *location_with_version_dir;
struct stat st;
+ bool in_place;
linkloc = psprintf("pg_tblspc/%u", tablespaceoid);
- location_with_version_dir = psprintf("%s/%s", location,
+
+ /*
+ * If we're asked to make an 'in place' tablespace, create the directory
+ * directly where the symlink would normally go. This is a developer-only
+ * option for now, to facilitate regression testing.
+ */
+ in_place = strlen(location) == 0;
+
+ if (in_place)
+ {
+ if (mkdir(linkloc, S_IRWXU) < 0 && errno != EEXIST)
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not create directory \"%s\": %m",
+ linkloc)));
+ }
+
+ location_with_version_dir = psprintf("%s/%s", in_place ? linkloc : location,
TABLESPACE_VERSION_DIRECTORY);
/*
* Attempt to coerce target directory to safe permissions. If this fails,
- * it doesn't exist or has the wrong owner.
+ * it doesn't exist or has the wrong owner. Not needed for in-place mode,
+ * because in that case we created the directory with the desired
+ * permissions.
*/
- if (chmod(location, S_IRWXU) != 0)
+ if (!in_place && chmod(location, S_IRWXU) != 0)
{
if (errno == ENOENT)
ereport(ERROR,
/*
* In recovery, remove old symlink, in case it points to the wrong place.
*/
- if (InRecovery)
+ if (!in_place && InRecovery)
remove_tablespace_symlink(linkloc);
/*
* Create the symlink under PGDATA
*/
- if (symlink(location, linkloc) < 0)
+ if (!in_place && symlink(location, linkloc) < 0)
ereport(ERROR,
(errcode_for_file_access(),
errmsg("could not create symbolic link \"%s\": %m",
#include <sys/file.h>
#include <signal.h>
+#include <sys/stat.h>
#include <dirent.h>
#include <fcntl.h>
#include <math.h>
char sourcepath[MAXPGPATH];
char targetpath[MAXPGPATH];
int rllen;
+#ifndef WIN32
+ struct stat st;
+#endif
/*
* It's useful to apply this function to pg_class.reltablespace, wherein
*/
snprintf(sourcepath, sizeof(sourcepath), "pg_tblspc/%u", tablespaceOid);
+ /*
+ * Before reading the link, check if the source path is a link or a
+ * junction point. Note that a directory is possible for a tablespace
+ * created with allow_in_place_tablespaces enabled. If a directory is
+ * found, a relative path to the data directory is returned.
+ */
+#ifdef WIN32
+ if (!pgwin32_is_junction(sourcepath))
+ PG_RETURN_TEXT_P(cstring_to_text(sourcepath));
+#else
+ if (lstat(sourcepath, &st) < 0)
+ {
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not stat file \"%s\": %m",
+ sourcepath)));
+ }
+
+ if (!S_ISLNK(st.st_mode))
+ PG_RETURN_TEXT_P(cstring_to_text(sourcepath));
+#endif
+
+ /*
+ * In presence of a link or a junction point, return the path pointing to.
+ */
rllen = readlink(sourcepath, targetpath, sizeof(targetpath));
if (rllen < 0)
ereport(ERROR,
#include "catalog/pg_authid.h"
#include "commands/async.h"
#include "commands/prepare.h"
+#include "commands/tablespace.h"
#include "commands/user.h"
#include "commands/vacuum.h"
#include "commands/variable.h"
NULL, NULL, NULL
},
+ {
+ {"allow_in_place_tablespaces", PGC_SUSET, DEVELOPER_OPTIONS,
+ gettext_noop("Allows tablespaces directly inside pg_tblspc, for testing."),
+ NULL,
+ GUC_NOT_IN_SAMPLE
+ },
+ &allow_in_place_tablespaces,
+ false,
+ NULL, NULL, NULL
+ },
+
{
{"lo_compat_privileges", PGC_SUSET, COMPAT_OPTIONS_PREVIOUS,
gettext_noop("Enables backward compatibility mode for privilege checks on large objects."),
#include "lib/stringinfo.h"
#include "nodes/parsenodes.h"
+extern bool allow_in_place_tablespaces;
+
/* XLOG stuff */
#define XLOG_TBLSPC_CREATE 0x00
#define XLOG_TBLSPC_DROP 0x10
projects / thirdparty / postgresql.git / commitdiff
