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mirror of https://github.com/pgbackrest/pgbackrest.git synced 2024-12-14 10:13:05 +02:00
pgbackrest/lib/pgBackRest/BackupFile.pm
David Steele 36a5349b1c Added the --checksum-page option.
This option allows pgBackRest to validate page checksums in data files when checksums are enabled on PostgreSQL >= 9.3. Note that this functionality requires a C library which may not initially be available in OS packages. The option will automatically be enabled when the library is present and checksums are enabled on the cluster.
2016-12-12 18:54:07 -05:00

457 lines
19 KiB
Perl

####################################################################################################################################
# BACKUP FILE MODULE
####################################################################################################################################
package pgBackRest::BackupFile;
use strict;
use warnings FATAL => qw(all);
use Carp qw(confess);
use Exporter qw(import);
our @EXPORT = qw();
use File::Basename qw(dirname);
use Storable qw(dclone);
use pgBackRest::DbVersion;
use pgBackRest::Common::Exception;
use pgBackRest::Common::Log;
use pgBackRest::Common::String;
use pgBackRest::File;
use pgBackRest::FileCommon;
use pgBackRest::Manifest;
use pgBackRest::Protocol::Common;
####################################################################################################################################
# Result constants
####################################################################################################################################
use constant BACKUP_FILE_CHECKSUM => 0;
push @EXPORT, qw(BACKUP_FILE_CHECKSUM);
use constant BACKUP_FILE_COPY => 1;
push @EXPORT, qw(BACKUP_FILE_COPY);
use constant BACKUP_FILE_RECOPY => 2;
push @EXPORT, qw(BACKUP_FILE_RECOPY);
use constant BACKUP_FILE_SKIP => 3;
push @EXPORT, qw(BACKUP_FILE_SKIP);
####################################################################################################################################
# Load the C library if present
####################################################################################################################################
my $bLibC = false;
eval
{
# Load the C library only if page checksums are required
require pgBackRest::LibC;
pgBackRest::LibC->import(qw(:checksum));
$bLibC = true;
return 1;
} or do {};
####################################################################################################################################
# isLibC
#
# Does the C library exist?
####################################################################################################################################
sub isLibC
{
return $bLibC;
}
push @EXPORT, qw(isLibC);
####################################################################################################################################
# backupChecksumPage
####################################################################################################################################
sub backupChecksumPage
{
my $tBufferRef = shift;
my $iBufferSize = shift;
my $iBufferOffset = shift;
my $hExtra = shift;
# Initialize the extra hash
if (!defined($hExtra->{bValid}))
{
$hExtra->{bValid} = true;
}
# Return when buffer is 0
if ($iBufferSize == 0)
{
# Make sure valid is set for 0 length files
if ($iBufferOffset == 0 && !defined($hExtra->{bValid}))
{
$hExtra->{bValid} = true;
}
return;
}
# Error if offset is not divisible by page size
if ($iBufferOffset % PG_PAGE_SIZE != 0)
{
confess &log(ASSERT, "should not be possible to see misaligned buffer offset ${iBufferOffset}, buffer size ${iBufferSize}");
}
# If the buffer is not divisible by 0 then it's not valid
if ($iBufferSize % PG_PAGE_SIZE != 0)
{
if (defined($hExtra->{bAlign}))
{
confess &log(ASSERT, "should not be possible to see two misaligned blocks in a row");
}
$hExtra->{bValid} = false;
$hExtra->{bAlign} = false;
delete($hExtra->{iyPageError});
}
elsif ($iBufferSize > 0)
{
if (!pageChecksumBuffer($$tBufferRef, $iBufferSize, int($iBufferOffset / PG_PAGE_SIZE), PG_PAGE_SIZE))
{
$hExtra->{bValid} = false;
# Now figure out exactly where the errors occurred. It would be more efficient if the checksum function returned an
# array, but we're hoping there won't be that many errors to scan so this should work fine.
for (my $iBlockNo = 0; $iBlockNo < int($iBufferSize / PG_PAGE_SIZE); $iBlockNo++)
{
my $iBlockNoStart = int($iBufferOffset / PG_PAGE_SIZE) + $iBlockNo;
if (!pageChecksumTest(
substr($$tBufferRef, $iBlockNo * PG_PAGE_SIZE, PG_PAGE_SIZE), $iBlockNoStart, PG_PAGE_SIZE))
{
my $iLastIdx = defined($hExtra->{iyPageError}) ? @{$hExtra->{iyPageError}} - 1 : 0;
my $iyLast = defined($hExtra->{iyPageError}) ? $hExtra->{iyPageError}[$iLastIdx] : undef;
if (!defined($iyLast) || (!ref($iyLast) && $iyLast != $iBlockNoStart - 1) ||
(ref($iyLast) && $iyLast->[1] != $iBlockNoStart - 1))
{
push(@{$hExtra->{iyPageError}}, $iBlockNoStart);
}
elsif (!ref($iyLast))
{
$hExtra->{iyPageError}[$iLastIdx] = undef;
push(@{$hExtra->{iyPageError}[$iLastIdx]}, $iyLast);
push(@{$hExtra->{iyPageError}[$iLastIdx]}, $iBlockNoStart);
}
else
{
$hExtra->{iyPageError}[$iLastIdx][1] = $iBlockNoStart;
}
}
}
}
}
}
####################################################################################################################################
# backupFile
####################################################################################################################################
sub backupFile
{
# Assign function parameters, defaults, and log debug info
my
(
$strOperation,
$oFile, # File object
$strDbFile, # Database file to backup
$strRepoFile, # Location in the repository to copy to
$lSizeFile, # File size
$strChecksum, # File checksum to be checked
$bChecksumPage, # Should page checksums be calculated?
$bDestinationCompress, # Compress destination file
$lModificationTime, # File modification time
$bIgnoreMissing, # Is it OK if the file is missing?
) =
logDebugParam
(
__PACKAGE__ . '::backupFile', \@_,
{name => 'oFile', trace => true},
{name => 'strDbFile', trace => true},
{name => 'strRepoFile', trace => true},
{name => 'lSizeFile', trace => true},
{name => 'strChecksum', required => false, trace => true},
{name => 'bChecksumPage', trace => true},
{name => 'bDestinationCompress', trace => true},
{name => 'lModificationTime', trace => true},
{name => 'bIgnoreMissing', default => true, trace => true},
);
my $iCopyResult = BACKUP_FILE_COPY; # Copy result
my $strCopyChecksum; # Copy checksum
my $rExtra; # Page checksum result
my $lCopySize; # Copy Size
my $lRepoSize; # Repo size
# If checksum is defined then the file already exists but needs to be checked
my $bCopy = true;
# Add compression suffix if needed
my $strFileOp = $strRepoFile . ($bDestinationCompress ? '.' . $oFile->{strCompressExtension} : '');
if (defined($strChecksum))
{
($strCopyChecksum, $lCopySize) =
$oFile->hashSize(PATH_BACKUP_TMP, $strFileOp, $bDestinationCompress);
$bCopy = !($strCopyChecksum eq $strChecksum && $lCopySize == $lSizeFile);
if ($bCopy)
{
$iCopyResult = BACKUP_FILE_RECOPY;
}
else
{
$iCopyResult = BACKUP_FILE_CHECKSUM;
}
}
if ($bCopy)
{
# Copy the file from the database to the backup (will return false if the source file is missing)
(my $bCopyResult, $strCopyChecksum, $lCopySize, $rExtra) = $oFile->copy(
PATH_DB_ABSOLUTE, $strDbFile,
PATH_BACKUP_TMP, $strFileOp,
false, # Source is not compressed since it is the db directory
$bDestinationCompress, # Destination should be compressed based on backup settings
$bIgnoreMissing, # Ignore missing files
$lModificationTime, # Set modification time - this is required for resume
undef, # Do not set original mode
true, # Create the destination directory if it does not exist
undef, undef, undef, undef, # Unused
$bChecksumPage ? # Function to process page checksums
'pgBackRest::BackupFile::backupChecksumPage' : undef);
# If source file is missing then assume the database removed it (else corruption and nothing we can do!)
if (!$bCopyResult)
{
$iCopyResult = BACKUP_FILE_SKIP;
}
}
# If file was copied or checksum'd then get size in repo. This has to be checked after the file is at rest because filesystem
# compression may affect the actual repo size and this cannot be calculated in stream.
if ($iCopyResult == BACKUP_FILE_COPY || $iCopyResult == BACKUP_FILE_RECOPY || $iCopyResult == BACKUP_FILE_CHECKSUM)
{
$lRepoSize = (fileStat($oFile->pathGet(PATH_BACKUP_TMP, $strFileOp)))->size;
}
# Return from function and log return values if any
return logDebugReturn
(
$strOperation,
{name => 'iCopyResult', value => $iCopyResult, trace => true},
{name => 'lCopySize', value => $lCopySize, trace => true},
{name => 'lRepoSize', value => $lRepoSize, trace => true},
{name => 'strCopyChecksum', value => $strCopyChecksum, trace => true},
{name => 'rExtra', value => $rExtra, trace => true},
);
}
push @EXPORT, qw(backupFile);
####################################################################################################################################
# backupManifestUpdate
####################################################################################################################################
sub backupManifestUpdate
{
# Assign function parameters, defaults, and log debug info
my
(
$strOperation,
$oManifest,
$strHost,
$iLocalId,
$strDbFile,
$strRepoFile,
$lSize,
$strChecksum,
$bChecksumPage,
$iCopyResult,
$lSizeCopy,
$lSizeRepo,
$strChecksumCopy,
$rExtra,
$lSizeTotal,
$lSizeCurrent,
$lManifestSaveSize,
$lManifestSaveCurrent
) =
logDebugParam
(
__PACKAGE__ . '::backupManifestUpdate', \@_,
{name => 'oManifest', trace => true},
{name => 'strHost', required => false, trace => true},
{name => 'iLocalId', required => false, trace => true},
# Parameters to backupFile()
{name => 'strDbFile', trace => true},
{name => 'strRepoFile', trace => true},
{name => 'lSize', required => false, trace => true},
{name => 'strChecksum', required => false, trace => true},
{name => 'bChecksumPage', trace => true},
# Results from backupFile()
{name => 'iCopyResult', trace => true},
{name => 'lSizeCopy', required => false, trace => true},
{name => 'lSizeRepo', required => false, trace => true},
{name => 'strChecksumCopy', required => false, trace => true},
{name => 'rExtra', required => false, trace => true},
# Accumulators
{name => 'lSizeTotal', trace => true},
{name => 'lSizeCurrent', trace => true},
{name => 'lManifestSaveSize', trace => true},
{name => 'lManifestSaveCurrent', trace => true}
);
# Increment current backup progress
$lSizeCurrent += $lSize;
# Log invalid checksum
if ($iCopyResult == BACKUP_FILE_RECOPY)
{
&log(
WARN,
"resumed backup file ${strRepoFile} should have checksum ${strChecksum} but actually has checksum ${strChecksumCopy}." .
" The file will be recopied and backup will continue but this may be an issue unless the backup temp path is known to" .
" be corrupted.");
}
# If copy was successful store the checksum and size
if ($iCopyResult == BACKUP_FILE_COPY || $iCopyResult == BACKUP_FILE_RECOPY || $iCopyResult == BACKUP_FILE_CHECKSUM)
{
# Log copy or checksum
&log($iCopyResult == BACKUP_FILE_CHECKSUM ? DETAIL : INFO,
($iCopyResult == BACKUP_FILE_CHECKSUM ?
'checksum resumed file ' : 'backup file ' . (defined($strHost) ? "${strHost}:" : '')) .
"${strDbFile} (" . fileSizeFormat($lSizeCopy) .
', ' . int($lSizeCurrent * 100 / $lSizeTotal) . '%)' .
($lSizeCopy != 0 ? " checksum ${strChecksumCopy}" : ''), undef, undef, undef, $iLocalId);
$oManifest->numericSet(MANIFEST_SECTION_TARGET_FILE, $strRepoFile, MANIFEST_SUBKEY_SIZE, $lSizeCopy);
if ($lSizeRepo != $lSizeCopy)
{
$oManifest->numericSet(MANIFEST_SECTION_TARGET_FILE, $strRepoFile, MANIFEST_SUBKEY_REPO_SIZE, $lSizeRepo);
}
if ($lSizeCopy > 0)
{
$oManifest->set(MANIFEST_SECTION_TARGET_FILE, $strRepoFile, MANIFEST_SUBKEY_CHECKSUM, $strChecksumCopy);
}
# If the file had page checksums calculated during the copy
if ($bChecksumPage)
{
# The valid flag should be set
if (defined($rExtra->{bValid}))
{
# Store the valid flag
$oManifest->boolSet(MANIFEST_SECTION_TARGET_FILE, $strRepoFile, MANIFEST_SUBKEY_CHECKSUM_PAGE, $rExtra->{bValid});
# If the page was not valid
if (!$rExtra->{bValid})
{
# Check for a page misalignment
if ($lSizeCopy % PG_PAGE_SIZE != 0)
{
# Make sure the align flag was set, otherwise there is a bug
if (!defined($rExtra->{bAlign}) || $rExtra->{bAlign})
{
confess &log(ASSERT, 'bAlign flag should have been set for misaligned page');
}
# Emit a warning so the user knows something is amiss
&log(WARN,
'page misalignment in file ' . (defined($strHost) ? "${strHost}:" : '') .
"${strDbFile}: file size ${lSizeCopy} is not divisible by page size " . PG_PAGE_SIZE);
}
# Else process the page check errors
else
{
$oManifest->set(
MANIFEST_SECTION_TARGET_FILE, $strRepoFile, MANIFEST_SUBKEY_CHECKSUM_PAGE_ERROR,
dclone($rExtra->{iyPageError}));
# Build a pretty list of the page errors
my $strPageError;
my $iPageErrorTotal = 0;
foreach my $iyPage (@{$rExtra->{iyPageError}})
{
$strPageError .= (defined($strPageError) ? ', ' : '');
# If a range of pages
if (ref($iyPage))
{
$strPageError .= $$iyPage[0] . '-' . $$iyPage[1];
$iPageErrorTotal += ($$iyPage[1] - $$iyPage[0]) + 1;
}
# Else a single page
else
{
$strPageError .= $iyPage;
$iPageErrorTotal += 1;
}
}
# There should be at least one page in the error list
if ($iPageErrorTotal == 0)
{
confess &log(ASSERT, 'page checksum error list should have at least one entry');
}
# Emit a warning so the user knows something is amiss
&log(WARN,
'invalid page checksum' . ($iPageErrorTotal > 1 ? 's' : '') .
' found in file ' . (defined($strHost) ? "${strHost}:" : '') . "${strDbFile} at page" .
($iPageErrorTotal > 1 ? 's' : '') . " ${strPageError}");
}
}
}
# If it's not set that's a bug in the code
elsif (!$oManifest->test(MANIFEST_SECTION_TARGET_FILE, $strRepoFile, MANIFEST_SUBKEY_CHECKSUM_PAGE))
{
confess &log(ASSERT, "${strDbFile} should have calculated page checksums");
}
}
}
# Else the file was removed during backup so remove from manifest
elsif ($iCopyResult == BACKUP_FILE_SKIP)
{
&log(DETAIL, 'skip file removed by database ' . (defined($strHost) ? "${strHost}:" : '') . $strDbFile);
$oManifest->remove(MANIFEST_SECTION_TARGET_FILE, $strRepoFile);
}
# Determine whether to save the manifest
$lManifestSaveCurrent += $lSize;
if ($lManifestSaveCurrent >= $lManifestSaveSize)
{
$oManifest->save();
logDebugMisc
(
$strOperation, 'save manifest',
{name => 'lManifestSaveSize', value => $lManifestSaveSize},
{name => 'lManifestSaveCurrent', value => $lManifestSaveCurrent}
);
$lManifestSaveCurrent = 0;
}
# Return from function and log return values if any
return logDebugReturn
(
$strOperation,
{name => 'lSizeCurrent', value => $lSizeCurrent, trace => true},
{name => 'lManifestSaveCurrent', value => $lManifestSaveCurrent, trace => true},
);
}
push @EXPORT, qw(backupManifestUpdate);
1;