Hi,
Am Dienstag, den 19.02.2019, 14:02 +0900 schrieb Michael Paquier:
> On Sun, Feb 17, 2019 at 07:31:38PM +0100, Michael Banck wrote:
> > New patch attached.
>
> - * src/bin/pg_verify_checksums/pg_verify_checksums.c
> + * src/bin/pg_checksums/pg_checksums.c
> That's lacking a rename, or this comment is incorrect.
Right, I started the rename, but then backed off pending further
discussion whether I should submit that or whether the committer will
just do it.
I've backed those 4 in-file renames out for now.
> +#if PG_VERSION_NUM >= 100000
> + StaticAssertStmt(sizeof(ControlFileData) <= PG_CONTROL_MAX_SAFE_SIZE,
> + "pg_control is too large for atomic disk writes");
> +#endif
> This is compiled with only one version of the control file data, so
> you don't need that.
Oops, yeah.
> Any reason why we don't refactor updateControlFile() into
> controldata_utils.c? This duplicates the code, at the exception of
> some details.
Ok, I've done that now, and migrated pg_rewind as well, do you know of
any other programs that might benefit here?
This could/should probably be committed separately beforehand.
New patch attached.
Michael
--
Michael Banck
Projektleiter / Senior Berater
Tel.: +49 2166 9901-171
Fax: +49 2166 9901-100
Email: michael.ba...@credativ.de
credativ GmbH, HRB Mönchengladbach 12080
USt-ID-Nummer: DE204566209
Trompeterallee 108, 41189 Mönchengladbach
Geschäftsführung: Dr. Michael Meskes, Jörg Folz, Sascha Heuer
Unser Umgang mit personenbezogenen Daten unterliegt
folgenden Bestimmungen: https://www.credativ.de/datenschutz
diff --git a/doc/src/sgml/ref/pg_verify_checksums.sgml b/doc/src/sgml/ref/pg_verify_checksums.sgml
index 905b8f1222..a565cb52ae 100644
--- a/doc/src/sgml/ref/pg_verify_checksums.sgml
+++ b/doc/src/sgml/ref/pg_verify_checksums.sgml
@@ -16,7 +16,7 @@ PostgreSQL documentation
<refnamediv>
<refname>pg_verify_checksums</refname>
- <refpurpose>verify data checksums in a <productname>PostgreSQL</productname> database cluster</refpurpose>
+ <refpurpose>enable, disable or verify data checksums in a <productname>PostgreSQL</productname> database cluster</refpurpose>
</refnamediv>
<refsynopsisdiv>
@@ -25,6 +25,11 @@ PostgreSQL documentation
<arg rep="repeat" choice="opt"><replaceable class="parameter">option</replaceable></arg>
<group choice="opt">
<group choice="opt">
+ <arg choice="plain"><option>--check</option></arg>
+ <arg choice="plain"><option>--disable</option></arg>
+ <arg choice="plain"><option>--enable</option></arg>
+ </group>
+ <group choice="opt">
<arg choice="plain"><option>-D</option></arg>
<arg choice="plain"><option>--pgdata</option></arg>
</group>
@@ -36,10 +41,18 @@ PostgreSQL documentation
<refsect1 id="r1-app-pg_verify_checksums-1">
<title>Description</title>
<para>
- <command>pg_verify_checksums</command> verifies data checksums in a
- <productname>PostgreSQL</productname> cluster. The server must be shut
- down cleanly before running <application>pg_verify_checksums</application>.
- The exit status is zero if there are no checksum errors, otherwise nonzero.
+ <command>pg_verify_checksums</command> enable, disable or verifies data
+ checksums in a <productname>PostgreSQL</productname> cluster. The server
+ must be shut down cleanly before running
+ <application>pg_verify_checksums</application> .
+ The exit status is zero if there are no checksum errors or checksum
+ enabling/disabled was successful, otherwise nonzero.
+ </para>
+
+ <para>
+ While checking or enabling checksums needs to scan or write every file in
+ the cluster, disabling will only update the <filename>pg_control</filename>
+ file.
</para>
</refsect1>
@@ -61,6 +74,36 @@ PostgreSQL documentation
</varlistentry>
<varlistentry>
+ <term><option>-c</option></term>
+ <term><option>--check</option></term>
+ <listitem>
+ <para>
+ Verify checksums.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>-d</option></term>
+ <term><option>--disable</option></term>
+ <listitem>
+ <para>
+ Disable checksums.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>-e</option></term>
+ <term><option>--enable</option></term>
+ <listitem>
+ <para>
+ Enable checksums.
+ </para>
+ </listitem>
+ </varlistentry>
+
+ <varlistentry>
<term><option>-v</option></term>
<term><option>--verbose</option></term>
<listitem>
diff --git a/src/bin/pg_rewind/pg_rewind.c b/src/bin/pg_rewind/pg_rewind.c
index aa753bb315..2420aef870 100644
--- a/src/bin/pg_rewind/pg_rewind.c
+++ b/src/bin/pg_rewind/pg_rewind.c
@@ -37,7 +37,6 @@ static void createBackupLabel(XLogRecPtr startpoint, TimeLineID starttli,
static void digestControlFile(ControlFileData *ControlFile, char *source,
size_t size);
-static void updateControlFile(ControlFileData *ControlFile);
static void syncTargetDirectory(void);
static void sanityChecks(void);
static void findCommonAncestorTimeline(XLogRecPtr *recptr, int *tliIndex);
@@ -377,7 +376,7 @@ main(int argc, char **argv)
ControlFile_new.minRecoveryPoint = endrec;
ControlFile_new.minRecoveryPointTLI = endtli;
ControlFile_new.state = DB_IN_ARCHIVE_RECOVERY;
- updateControlFile(&ControlFile_new);
+ update_controlfile(datadir_target, progname, &ControlFile_new);
pg_log(PG_PROGRESS, "syncing target data directory\n");
syncTargetDirectory();
@@ -667,45 +666,6 @@ digestControlFile(ControlFileData *ControlFile, char *src, size_t size)
}
/*
- * Update the target's control file.
- */
-static void
-updateControlFile(ControlFileData *ControlFile)
-{
- char buffer[PG_CONTROL_FILE_SIZE];
-
- /*
- * For good luck, apply the same static assertions as in backend's
- * WriteControlFile().
- */
- StaticAssertStmt(sizeof(ControlFileData) <= PG_CONTROL_MAX_SAFE_SIZE,
- "pg_control is too large for atomic disk writes");
- StaticAssertStmt(sizeof(ControlFileData) <= PG_CONTROL_FILE_SIZE,
- "sizeof(ControlFileData) exceeds PG_CONTROL_FILE_SIZE");
-
- /* Recalculate CRC of control file */
- INIT_CRC32C(ControlFile->crc);
- COMP_CRC32C(ControlFile->crc,
- (char *) ControlFile,
- offsetof(ControlFileData, crc));
- FIN_CRC32C(ControlFile->crc);
-
- /*
- * Write out PG_CONTROL_FILE_SIZE bytes into pg_control by zero-padding
- * the excess over sizeof(ControlFileData), to avoid premature EOF related
- * errors when reading it.
- */
- memset(buffer, 0, PG_CONTROL_FILE_SIZE);
- memcpy(buffer, ControlFile, sizeof(ControlFileData));
-
- open_target_file("global/pg_control", false);
-
- write_target_range(buffer, 0, PG_CONTROL_FILE_SIZE);
-
- close_target_file();
-}
-
-/*
* Sync target data directory to ensure that modifications are safely on disk.
*
* We do this once, for the whole data directory, for performance reasons. At
diff --git a/src/bin/pg_verify_checksums/pg_verify_checksums.c b/src/bin/pg_verify_checksums/pg_verify_checksums.c
index 511262ab5f..f75bf9fcf5 100644
--- a/src/bin/pg_verify_checksums/pg_verify_checksums.c
+++ b/src/bin/pg_verify_checksums/pg_verify_checksums.c
@@ -1,7 +1,7 @@
/*
* pg_verify_checksums
*
- * Verifies page level checksums in an offline cluster
+ * Verifies/enables/disables page level checksums in an offline cluster
*
* Copyright (c) 2010-2019, PostgreSQL Global Development Group
*
@@ -13,14 +13,16 @@
#include <sys/stat.h>
#include <unistd.h>
+#include "access/xlog_internal.h"
#include "catalog/pg_control.h"
#include "common/controldata_utils.h"
+#include "common/file_perm.h"
+#include "common/file_utils.h"
#include "getopt_long.h"
#include "pg_getopt.h"
#include "storage/bufpage.h"
#include "storage/checksum.h"
#include "storage/checksum_impl.h"
-#include "storage/fd.h"
static int64 files = 0;
@@ -31,16 +33,33 @@ static ControlFileData *ControlFile;
static char *only_relfilenode = NULL;
static bool verbose = false;
+typedef enum
+{
+ PG_ACTION_CHECK,
+ PG_ACTION_DISABLE,
+ PG_ACTION_ENABLE
+} ChecksumAction;
+
+/* Filename components */
+#define PG_TEMP_FILES_DIR "pgsql_tmp"
+#define PG_TEMP_FILE_PREFIX "pgsql_tmp"
+
+static ChecksumAction action = PG_ACTION_CHECK;
+
static const char *progname;
static void
usage(void)
{
- printf(_("%s verifies data checksums in a PostgreSQL database cluster.\n\n"), progname);
+ printf(_("%s enables/disables/verifies data checksums in a PostgreSQL database cluster.\n\n"), progname);
printf(_("Usage:\n"));
printf(_(" %s [OPTION]... [DATADIR]\n"), progname);
printf(_("\nOptions:\n"));
printf(_(" [-D, --pgdata=]DATADIR data directory\n"));
+ printf(_(" -c, --check check data checksums\n"));
+ printf(_(" -d, --disable disable data checksums\n"));
+ printf(_(" -e, --enable enable data checksums\n"));
+ printf(_(" \"check\", \"enable\" and \"disable\"\n"));
printf(_(" -v, --verbose output verbose messages\n"));
printf(_(" -r RELFILENODE check only relation with specified relfilenode\n"));
printf(_(" -V, --version output version information, then exit\n"));
@@ -87,7 +106,11 @@ scan_file(const char *fn, BlockNumber segmentno)
int f;
BlockNumber blockno;
- f = open(fn, O_RDONLY | PG_BINARY, 0);
+ Assert(action == PG_ACTION_ENABLE ||
+ action == PG_ACTION_CHECK);
+
+ f = open(fn, action == PG_ACTION_ENABLE ? O_RDWR : O_RDONLY | PG_BINARY, 0);
+
if (f < 0)
{
fprintf(stderr, _("%s: could not open file \"%s\": %s\n"),
@@ -117,18 +140,47 @@ scan_file(const char *fn, BlockNumber segmentno)
continue;
csum = pg_checksum_page(buf.data, blockno + segmentno * RELSEG_SIZE);
- if (csum != header->pd_checksum)
+ if (action == PG_ACTION_CHECK)
{
- if (ControlFile->data_checksum_version == PG_DATA_CHECKSUM_VERSION)
- fprintf(stderr, _("%s: checksum verification failed in file \"%s\", block %u: calculated checksum %X but block contains %X\n"),
- progname, fn, blockno, csum, header->pd_checksum);
- badblocks++;
+ if (csum != header->pd_checksum)
+ {
+ if (ControlFile->data_checksum_version == PG_DATA_CHECKSUM_VERSION)
+ fprintf(stderr, _("%s: checksum verification failed in file \"%s\", block %u: calculated checksum %X but block contains %X\n"),
+ progname, fn, blockno, csum, header->pd_checksum);
+ badblocks++;
+ }
+ }
+ else if (action == PG_ACTION_ENABLE)
+ {
+ /* Set checksum in page header */
+ header->pd_checksum = csum;
+
+ /* Seek back to beginning of block */
+ if (lseek(f, -BLCKSZ, SEEK_CUR) < 0)
+ {
+ fprintf(stderr, _("%s: seek failed for block %d in file \"%s\": %s\n"), progname, blockno, fn, strerror(errno));
+ exit(1);
+ }
+
+ /* Write block with checksum */
+ if (write(f, buf.data, BLCKSZ) != BLCKSZ)
+ {
+ fprintf(stderr, "%s: could not update checksum of block %d in file \"%s\": %s\n",
+ progname, blockno, fn, strerror(errno));
+ exit(1);
+ }
}
}
if (verbose)
- fprintf(stderr,
- _("%s: checksums verified in file \"%s\"\n"), progname, fn);
+ {
+ if (action == PG_ACTION_CHECK)
+ fprintf(stderr,
+ _("%s: checksums verified in file \"%s\"\n"), progname, fn);
+ if (action == PG_ACTION_ENABLE)
+ fprintf(stderr,
+ _("%s: checksums enabled in file \"%s\"\n"), progname, fn);
+ }
close(f);
}
@@ -230,14 +282,19 @@ int
main(int argc, char *argv[])
{
static struct option long_options[] = {
+ {"check", no_argument, NULL, 'c'},
{"pgdata", required_argument, NULL, 'D'},
+ {"disable", no_argument, NULL, 'd'},
+ {"enable", no_argument, NULL, 'e'},
{"verbose", no_argument, NULL, 'v'},
{NULL, 0, NULL, 0}
};
char *DataDir = NULL;
+ char pid_file[MAXPGPATH];
int c;
int option_index;
+ int pidf;
bool crc_ok;
set_pglocale_pgservice(argv[0], PG_TEXTDOMAIN("pg_verify_checksums"));
@@ -258,10 +315,19 @@ main(int argc, char *argv[])
}
}
- while ((c = getopt_long(argc, argv, "D:r:v", long_options, &option_index)) != -1)
+ while ((c = getopt_long(argc, argv, "cD:der:v", long_options, &option_index)) != -1)
{
switch (c)
{
+ case 'c':
+ action = PG_ACTION_CHECK;
+ break;
+ case 'd':
+ action = PG_ACTION_DISABLE;
+ break;
+ case 'e':
+ action = PG_ACTION_ENABLE;
+ break;
case 'v':
verbose = true;
break;
@@ -308,6 +374,16 @@ main(int argc, char *argv[])
exit(1);
}
+ /* Relfilenode checking only works in check mode */
+ if (action != PG_ACTION_CHECK &&
+ only_relfilenode)
+ {
+ fprintf(stderr, _("%s: relfilenode option only possible with check action\n"), progname);
+ fprintf(stderr, _("Try \"%s --help\" for more information.\n"),
+ progname);
+ exit(1);
+ }
+
/* Check if cluster is running */
ControlFile = get_controlfile(DataDir, progname, &crc_ok);
if (!crc_ok)
@@ -319,29 +395,85 @@ main(int argc, char *argv[])
if (ControlFile->state != DB_SHUTDOWNED &&
ControlFile->state != DB_SHUTDOWNED_IN_RECOVERY)
{
- fprintf(stderr, _("%s: cluster must be shut down to verify checksums\n"), progname);
+ fprintf(stderr, _("%s: cluster must be shut down\n"), progname);
exit(1);
}
- if (ControlFile->data_checksum_version == 0)
+ /* Also check for postmaster.pid file */
+ snprintf(pid_file, sizeof(pid_file), "%s/postmaster.pid", DataDir);
+ pidf = open(pid_file, O_RDONLY, 0);
+ if (pidf < 0)
+ {
+ /*
+ * if the errno is ENOENT, there is no pid file which is what we
+ * expect. Otherwise, it exits but we cannot open it so exit with
+ * failure.
+ */
+ if (errno != ENOENT)
+ {
+ fprintf(stderr, _("%s: postmaster.pid cannot be opened for reading: %s\n"),
+ progname, strerror(errno));
+ exit(1);
+ }
+ }
+ else
+ {
+ fprintf(stderr, _("%s: postmaster.pid exists, cluster must be shut down\n"), progname);
+ exit(1);
+ }
+
+ if (ControlFile->data_checksum_version == 0 &&
+ action == PG_ACTION_CHECK)
{
fprintf(stderr, _("%s: data checksums are not enabled in cluster\n"), progname);
exit(1);
}
+ if (ControlFile->data_checksum_version == 0 &&
+ action == PG_ACTION_DISABLE)
+ {
+ fprintf(stderr, _("%s: data checksums are already disabled in cluster.\n"), progname);
+ exit(1);
+ }
+ if (ControlFile->data_checksum_version == PG_DATA_CHECKSUM_VERSION &&
+ action == PG_ACTION_ENABLE)
+ {
+ fprintf(stderr, _("%s: data checksums are already enabled in cluster.\n"), progname);
+ exit(1);
+ }
- /* Scan all files */
- scan_directory(DataDir, "global");
- scan_directory(DataDir, "base");
- scan_directory(DataDir, "pg_tblspc");
+ if (action == PG_ACTION_CHECK || action == PG_ACTION_ENABLE)
+ {
+ /* Operate on all files */
+ scan_directory(DataDir, "global");
+ scan_directory(DataDir, "base");
+ scan_directory(DataDir, "pg_tblspc");
+
+ printf(_("Checksum operation completed\n"));
+ printf(_("Files scanned: %s\n"), psprintf(INT64_FORMAT, files));
+ printf(_("Blocks scanned: %s\n"), psprintf(INT64_FORMAT, blocks));
+ if (action == PG_ACTION_CHECK)
+ {
+ printf(_("Bad checksums: %s\n"), psprintf(INT64_FORMAT, badblocks));
+ printf(_("Data checksum version: %d\n"), ControlFile->data_checksum_version);
- printf(_("Checksum scan completed\n"));
- printf(_("Data checksum version: %d\n"), ControlFile->data_checksum_version);
- printf(_("Files scanned: %s\n"), psprintf(INT64_FORMAT, files));
- printf(_("Blocks scanned: %s\n"), psprintf(INT64_FORMAT, blocks));
- printf(_("Bad checksums: %s\n"), psprintf(INT64_FORMAT, badblocks));
+ if (badblocks > 0)
+ return 1;
+ }
+ }
- if (badblocks > 0)
- return 1;
+ if (action == PG_ACTION_ENABLE || action == PG_ACTION_DISABLE)
+ {
+ /* Update control file */
+ ControlFile->data_checksum_version = action == PG_ACTION_ENABLE ? PG_DATA_CHECKSUM_VERSION : 0;
+ update_controlfile(DataDir, progname, ControlFile);
+ fsync_pgdata(DataDir, progname, PG_VERSION_NUM);
+ if (verbose)
+ printf(_("Data checksum version: %d\n"), ControlFile->data_checksum_version);
+ if (action == PG_ACTION_ENABLE)
+ printf(_("Checksums enabled in cluster\n"));
+ else
+ printf(_("Checksums disabled in cluster\n"));
+ }
return 0;
}
diff --git a/src/bin/pg_verify_checksums/t/002_actions.pl b/src/bin/pg_verify_checksums/t/002_actions.pl
index 74ad5ad723..364c215cba 100644
--- a/src/bin/pg_verify_checksums/t/002_actions.pl
+++ b/src/bin/pg_verify_checksums/t/002_actions.pl
@@ -5,7 +5,7 @@ use strict;
use warnings;
use PostgresNode;
use TestLib;
-use Test::More tests => 45;
+use Test::More tests => 59;
# Utility routine to create and check a table with corrupted checksums
@@ -38,8 +38,8 @@ sub check_relation_corruption
# Checksums are correct for single relfilenode as the table is not
# corrupted yet.
- command_ok(['pg_verify_checksums', '-D', $pgdata,
- '-r', $relfilenode_corrupted],
+ command_ok(['pg_verify_checksums', '-c', '-D', $pgdata, '-r',
+ $relfilenode_corrupted],
"succeeds for single relfilenode on tablespace $tablespace with offline cluster");
# Time to create some corruption
@@ -49,15 +49,15 @@ sub check_relation_corruption
close $file;
# Checksum checks on single relfilenode fail
- $node->command_checks_all([ 'pg_verify_checksums', '-D', $pgdata, '-r',
- $relfilenode_corrupted],
+ $node->command_checks_all([ 'pg_verify_checksums', '-c', '-D', $pgdata,
+ '-r', $relfilenode_corrupted],
1,
[qr/Bad checksums:.*1/],
[qr/checksum verification failed/],
"fails with corrupted data for single relfilenode on tablespace $tablespace");
# Global checksum checks fail as well
- $node->command_checks_all([ 'pg_verify_checksums', '-D', $pgdata],
+ $node->command_checks_all([ 'pg_verify_checksums', '-c', '-D', $pgdata],
1,
[qr/Bad checksums:.*1/],
[qr/checksum verification failed/],
@@ -67,22 +67,22 @@ sub check_relation_corruption
$node->start;
$node->safe_psql('postgres', "DROP TABLE $table;");
$node->stop;
- $node->command_ok(['pg_verify_checksums', '-D', $pgdata],
+ $node->command_ok(['pg_verify_checksums', '-c', '-D', $pgdata],
"succeeds again after table drop on tablespace $tablespace");
$node->start;
return;
}
-# Initialize node with checksums enabled.
+# Initialize node with checksums disabled.
my $node = get_new_node('node_checksum');
-$node->init(extra => ['--data-checksums']);
+$node->init();
my $pgdata = $node->data_dir;
-# Control file should know that checksums are enabled.
+# Control file should know that checksums are disabled.
command_like(['pg_controldata', $pgdata],
- qr/Data page checksum version:.*1/,
- 'checksums enabled in control file');
+ qr/Data page checksum version:.*0/,
+ 'checksums disabled in control file');
# These are correct but empty files, so they should pass through.
append_to_file "$pgdata/global/99999", "";
@@ -100,13 +100,49 @@ append_to_file "$pgdata/global/pgsql_tmp_123", "foo";
mkdir "$pgdata/global/pgsql_tmp";
append_to_file "$pgdata/global/pgsql_tmp/1.1", "foo";
+# Enable checksums
+command_ok(['pg_verify_checksums', '-e', '-D', $pgdata],
+ "checksums successfully enabled in cluster");
+
+# Control file should know that checksums are enabled.
+command_like(['pg_controldata', $pgdata],
+ qr/Data page checksum version:.*1/,
+ 'checksums enabled in control file');
+
+# Disable checksums again
+command_ok(['pg_verify_checksums', '-d', '-D', $pgdata],
+ "checksums successfully disabled in cluster");
+
+# Control file should know that checksums are disabled.
+command_like(['pg_controldata', $pgdata],
+ qr/Data page checksum version:.*0/,
+ 'checksums disabled in control file');
+
+# Enable checksums again with long option
+command_ok(['pg_verify_checksums', '--enable', '-D', $pgdata],
+ "checksums successfully enabled in cluster");
+
+# Control file should know that checksums are enabled.
+command_like(['pg_controldata', $pgdata],
+ qr/Data page checksum version:.*1/,
+ 'checksums enabled in control file');
+
# Checksums pass on a newly-created cluster
-command_ok(['pg_verify_checksums', '-D', $pgdata],
+command_ok(['pg_verify_checksums', '-c', '-D', $pgdata],
"succeeds with offline cluster");
+# Checksums are verified if no other arguments are specified
+command_ok(['pg_verify_checksums', '-D', $pgdata],
+ "verifies checksums as default action");
+
+# Specific relation files cannot be requested when action is disable
+command_fails(['pg_verify_checksums', '-d', '-r', '1234', '-D',
+ $pgdata],
+ "fails when relfilnodes are requested and action is not verify");
+
# Checks cannot happen with an online cluster
$node->start;
-command_fails(['pg_verify_checksums', '-D', $pgdata],
+command_fails(['pg_verify_checksums', '-c', '-D', $pgdata],
"fails with online cluster");
# Check corruption of table on default tablespace.
@@ -133,7 +169,7 @@ sub fail_corrupt
my $file_name = "$pgdata/global/$file";
append_to_file $file_name, "foo";
- $node->command_checks_all([ 'pg_verify_checksums', '-D', $pgdata],
+ $node->command_checks_all([ 'pg_verify_checksums', '-c', '-D', $pgdata],
1,
[qr/^$/],
[qr/could not read block 0 in file.*$file\":/],
diff --git a/src/common/controldata_utils.c b/src/common/controldata_utils.c
index abfe7065f5..3d9b190dff 100644
--- a/src/common/controldata_utils.c
+++ b/src/common/controldata_utils.c
@@ -24,12 +24,14 @@
#include <sys/stat.h>
#include <fcntl.h>
+#include "access/xlog_internal.h"
#include "catalog/pg_control.h"
#include "common/controldata_utils.h"
+#include "common/file_perm.h"
#include "port/pg_crc32c.h"
/*
- * get_controlfile(char *DataDir, const char *progname, bool *crc_ok_p)
+ * get_controlfile(const char *DataDir, const char *progname, bool *crc_ok_p)
*
* Get controlfile values. The result is returned as a palloc'd copy of the
* control file data.
@@ -120,3 +122,75 @@ get_controlfile(const char *DataDir, const char *progname, bool *crc_ok_p)
return ControlFile;
}
+
+/*
+ * update_controlfile(const char *DataDir, const char *progname,
+ * ControlFileData *ControlFile)
+ *
+ * Update controlfile values with the content of ControlFile.
+ */
+void
+update_controlfile(const char *DataDir, const char *progname, ControlFileData *ControlFile)
+{
+ int fd;
+ char buffer[PG_CONTROL_FILE_SIZE];
+ char ControlFilePath[MAXPGPATH];
+
+ /*
+ * For good luck, apply the same static assertions as in backend's
+ * WriteControlFile().
+ */
+ StaticAssertStmt(sizeof(ControlFileData) <= PG_CONTROL_MAX_SAFE_SIZE,
+ "pg_control is too large for atomic disk writes");
+ StaticAssertStmt(sizeof(ControlFileData) <= PG_CONTROL_FILE_SIZE,
+ "sizeof(ControlFileData) exceeds PG_CONTROL_FILE_SIZE");
+
+ /* Recalculate CRC of control file */
+ INIT_CRC32C(ControlFile->crc);
+ COMP_CRC32C(ControlFile->crc,
+ (char *) ControlFile,
+ offsetof(ControlFileData, crc));
+ FIN_CRC32C(ControlFile->crc);
+
+ /*
+ * Write out PG_CONTROL_FILE_SIZE bytes into pg_control by zero-padding
+ * the excess over sizeof(ControlFileData), to avoid premature EOF related
+ * errors when reading it.
+ */
+ memset(buffer, 0, PG_CONTROL_FILE_SIZE);
+ memcpy(buffer, ControlFile, sizeof(ControlFileData));
+
+ snprintf(ControlFilePath, sizeof(ControlFilePath), "%s/%s", DataDir, XLOG_CONTROL_FILE);
+
+ fd = open(ControlFilePath, O_WRONLY | PG_BINARY,
+ pg_file_create_mode);
+ if (fd < 0)
+ {
+ fprintf(stderr, _("%s: could not open control file: %s\n"),
+ progname, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+
+ errno = 0;
+ if (write(fd, buffer, PG_CONTROL_FILE_SIZE) != PG_CONTROL_FILE_SIZE)
+ {
+ /* if write didn't set errno, assume problem is no disk space */
+ if (errno == 0)
+ errno = ENOSPC;
+ fprintf(stderr, _("%s: could not write control file: %s\n"),
+ progname, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+
+ if (fsync(fd) != 0)
+ {
+ fprintf(stderr, _("%s: fsync error: %s\n"), progname, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+
+ if (close(fd) < 0)
+ {
+ fprintf(stderr, _("%s: could not close control file: %s\n"), progname, strerror(errno));
+ exit(EXIT_FAILURE);
+ }
+}
diff --git a/src/include/common/controldata_utils.h b/src/include/common/controldata_utils.h
index 0ffa2000fc..0308f131e0 100644
--- a/src/include/common/controldata_utils.h
+++ b/src/include/common/controldata_utils.h
@@ -13,5 +13,6 @@
#include "catalog/pg_control.h"
extern ControlFileData *get_controlfile(const char *DataDir, const char *progname, bool *crc_ok_p);
+extern void update_controlfile(const char *DataDir, const char *progname, ControlFileData *ControlFile);
#endif /* COMMON_CONTROLDATA_UTILS_H */
