<?php
/**
- * This is a port of D.J. Bernstein's CDB to PHP. It's based on the copy that
+ * This is a port of D.J. Bernstein's CDB to PHP. It's based on the copy that
* appears in PHP 5.3. Changes are:
* * Error returns replaced with exceptions
* * Exception thrown if sizes or offsets are between 2GB and 4GB
* * Some variables renamed
*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
* @file
*/
/**
* Take a modulo of a signed integer as if it were an unsigned integer.
* $b must be less than 0x40000000 and greater than 0
+ *
+ * @param $a
+ * @param $b
+ *
+ * @return int
*/
public static function unsignedMod( $a, $b ) {
if ( $a & 0x80000000 ) {
return $a % $b;
}
}
-
+
/**
* Shift a signed integer right as if it were unsigned
+ * @param $a
+ * @param $b
+ * @return int
*/
public static function unsignedShiftRight( $a, $b ) {
if ( $b == 0 ) {
/**
* The CDB hash function.
+ *
+ * @param $s string
+ *
+ * @return
*/
public static function hash( $s ) {
$h = 5381;
// Do a 32-bit sum
// Inlined here for speed
$sum = ($h & 0x3fffffff) + ($h5 & 0x3fffffff);
- $h =
+ $h =
(
( $sum & 0x40000000 ? 1 : 0 )
+ ( $h & 0x80000000 ? 2 : 0 )
* CDB reader class
*/
class CdbReader_PHP extends CdbReader {
+ /** The filename */
+ var $fileName;
+
/** The file handle */
var $handle;
var $dpos;
/* initialized if cdb_findnext() returns 1 */
- var $dlen;
+ var $dlen;
+ /**
+ * @param $fileName string
+ * @throws MWException
+ */
function __construct( $fileName ) {
+ $this->fileName = $fileName;
$this->handle = fopen( $fileName, 'rb' );
if ( !$this->handle ) {
- throw new MWException( 'Unable to open DB file "' . $fileName . '"' );
+ throw new MWException( 'Unable to open CDB file "' . $this->fileName . '".' );
}
$this->findStart();
}
function close() {
- if( isset($this->handle) )
+ if( isset( $this->handle ) ) {
fclose( $this->handle );
+ }
unset( $this->handle );
}
+ /**
+ * @param $key
+ * @return bool|string
+ */
public function get( $key ) {
// strval is required
if ( $this->find( strval( $key ) ) ) {
}
}
+ /**
+ * @param $key
+ * @param $pos
+ * @return bool
+ */
protected function match( $key, $pos ) {
$buf = $this->read( strlen( $key ), $pos );
return $buf === $key;
$this->loop = 0;
}
+ /**
+ * @throws MWException
+ * @param $length
+ * @param $pos
+ * @return string
+ */
protected function read( $length, $pos ) {
if ( fseek( $this->handle, $pos ) == -1 ) {
// This can easily happen if the internal pointers are incorrect
- throw new MWException( __METHOD__.': seek failed, file may be corrupted.' );
+ throw new MWException(
+ 'Seek failed, file "' . $this->fileName . '" may be corrupted.' );
}
if ( $length == 0 ) {
$buf = fread( $this->handle, $length );
if ( $buf === false || strlen( $buf ) !== $length ) {
- throw new MWException( __METHOD__.': read from cdb file failed, file may be corrupted' );
+ throw new MWException(
+ 'Read from CDB file failed, file "' . $this->fileName . '" may be corrupted.' );
}
return $buf;
}
/**
* Unpack an unsigned integer and throw an exception if it needs more than 31 bits
+ * @param $s
+ * @throws MWException
+ * @return mixed
*/
protected function unpack31( $s ) {
$data = unpack( 'V', $s );
if ( $data[1] > 0x7fffffff ) {
- throw new MWException( __METHOD__.': error in CDB file, integer too big' );
+ throw new MWException(
+ 'Error in CDB file "' . $this->fileName . '", integer too big.' );
}
return $data[1];
}
/**
* Unpack a 32-bit signed integer
+ * @param $s
+ * @return int
*/
protected function unpackSigned( $s ) {
$data = unpack( 'va/vb', $s );
return $data['a'] | ( $data['b'] << 16 );
}
+ /**
+ * @param $key
+ * @return bool
+ */
protected function findNext( $key ) {
if ( !$this->loop ) {
$u = CdbFunctions::hash( $key );
return false;
}
+ /**
+ * @param $key
+ * @return bool
+ */
protected function find( $key ) {
$this->findStart();
return $this->findNext( $key );
var $handle, $realFileName, $tmpFileName;
var $hplist;
- var $numEntries, $pos;
+ var $numentries, $pos;
+ /**
+ * @param $fileName string
+ */
function __construct( $fileName ) {
$this->realFileName = $fileName;
$this->tmpFileName = $fileName . '.tmp.' . mt_rand( 0, 0x7fffffff );
$this->handle = fopen( $this->tmpFileName, 'wb' );
if ( !$this->handle ) {
- throw new MWException( 'Unable to open DB file for write "' . $fileName . '"' );
+ $this->throwException(
+ 'Unable to open CDB file "' . $this->tmpFileName . '" for write.' );
}
$this->hplist = array();
$this->numentries = 0;
$this->pos = 2048; // leaving space for the pointer array, 256 * 8
if ( fseek( $this->handle, $this->pos ) == -1 ) {
- throw new MWException( __METHOD__.': fseek failed' );
+ $this->throwException( 'fseek failed in file "' . $this->tmpFileName . '".' );
}
}
}
}
+ /**
+ * @param $key
+ * @param $value
+ * @return
+ */
public function set( $key, $value ) {
if ( strval( $key ) === '' ) {
// DBA cross-check hack
$this->addend( strlen( $key ), strlen( $value ), CdbFunctions::hash( $key ) );
}
+ /**
+ * @throws MWException
+ */
public function close() {
$this->finish();
- if( isset($this->handle) )
+ if( isset($this->handle) ) {
fclose( $this->handle );
+ }
if ( wfIsWindows() && file_exists($this->realFileName) ) {
unlink( $this->realFileName );
}
if ( !rename( $this->tmpFileName, $this->realFileName ) ) {
- throw new MWException( 'Unable to move the new CDB file into place.' );
+ $this->throwException( 'Unable to move the new CDB file into place.' );
}
unset( $this->handle );
}
+ /**
+ * @throws MWException
+ * @param $buf
+ */
protected function write( $buf ) {
$len = fwrite( $this->handle, $buf );
if ( $len !== strlen( $buf ) ) {
- throw new MWException( 'Error writing to CDB file.' );
+ $this->throwException( 'Error writing to CDB file "'.$this->tmpFileName.'".' );
}
}
+ /**
+ * @throws MWException
+ * @param $len
+ */
protected function posplus( $len ) {
$newpos = $this->pos + $len;
if ( $newpos > 0x7fffffff ) {
- throw new MWException( 'A value in the CDB file is too large' );
+ $this->throwException(
+ 'A value in the CDB file "'.$this->tmpFileName.'" is too large.' );
}
$this->pos = $newpos;
}
+ /**
+ * @param $keylen
+ * @param $datalen
+ * @param $h
+ */
protected function addend( $keylen, $datalen, $h ) {
$this->hplist[] = array(
'h' => $h,
$this->posplus( $datalen );
}
+ /**
+ * @throws MWException
+ * @param $keylen
+ * @param $datalen
+ */
protected function addbegin( $keylen, $datalen ) {
if ( $keylen > 0x7fffffff ) {
- throw new MWException( __METHOD__.': key length too long' );
+ $this->throwException( 'Key length too long in file "'.$this->tmpFileName.'".' );
}
if ( $datalen > 0x7fffffff ) {
- throw new MWException( __METHOD__.': data length too long' );
+ $this->throwException( 'Data length too long in file "'.$this->tmpFileName.'".' );
}
$buf = pack( 'VV', $keylen, $datalen );
$this->write( $buf );
}
+ /**
+ * @throws MWException
+ */
protected function finish() {
// Hack for DBA cross-check
$this->hplist = array_reverse( $this->hplist );
}
// Excessively clever and indulgent code to simultaneously fill $packedTables
- // with the packed hashtables, and adjust the elements of $starts
+ // with the packed hashtables, and adjust the elements of $starts
// to actually point to the starts instead of the ends.
$packedTables = array_fill( 0, $this->numentries, false );
foreach ( $this->hplist as $item ) {
// is taken.
for ( $u = 0; $u < $count; ++$u ) {
$hp = $packedTables[$starts[$i] + $u];
- $where = CdbFunctions::unsignedMod(
+ $where = CdbFunctions::unsignedMod(
CdbFunctions::unsignedShiftRight( $hp['h'], 8 ), $len );
while ( $hashtable[$where]['p'] )
if ( ++$where == $len )
// Write the hashtable
for ( $u = 0; $u < $len; ++$u ) {
- $buf = pack( 'vvV',
+ $buf = pack( 'vvV',
$hashtable[$u]['h'] & 0xffff,
CdbFunctions::unsignedShiftRight( $hashtable[$u]['h'], 16 ),
$hashtable[$u]['p'] );
// Write the pointer array at the start of the file
rewind( $this->handle );
if ( ftell( $this->handle ) != 0 ) {
- throw new MWException( __METHOD__.': Error rewinding to start of file' );
+ $this->throwException( 'Error rewinding to start of file "'.$this->tmpFileName.'".' );
}
$this->write( $final );
}
+
+ /**
+ * Clean up the temp file and throw an exception
+ *
+ * @param $msg string
+ * @throws MWException
+ */
+ protected function throwException( $msg ) {
+ if ( $this->handle ) {
+ fclose( $this->handle );
+ unlink( $this->tmpFileName );
+ }
+ throw new MWException( $msg );
+ }
}