<?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
+ *
+ * @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 < 0 ) {
+ if ( $a & 0x80000000 ) {
$m = ( $a & 0x7fffffff ) % $b + 2 * ( 0x40000000 % $b );
return $m % $b;
} else {
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 ) {
return $a;
}
- if ( $a < 0 ) {
+ if ( $a & 0x80000000 ) {
return ( ( $a & 0x7fffffff ) >> $b ) | ( 0x40000000 >> ( $b - 1 ) );
} else {
return $a >> $b;
/**
* The CDB hash function.
+ *
+ * @param $s
+ *
+ * @return
*/
public static function hash( $s ) {
$h = 5381;
for ( $i = 0; $i < strlen( $s ); $i++ ) {
- $h5 = $h << 5;
+ $h5 = ($h << 5) & 0xffffffff;
// Do a 32-bit sum
// Inlined here for speed
$sum = ($h & 0x3fffffff) + ($h5 & 0x3fffffff);
- $h =
+ $h =
(
( $sum & 0x40000000 ? 1 : 0 )
- + ( $h < 0 ? 2 : 0 )
+ + ( $h & 0x80000000 ? 2 : 0 )
+ ( $h & 0x40000000 ? 1 : 0 )
- + ( $h5 < 0 ? 2 : 0 )
+ + ( $h5 & 0x80000000 ? 2 : 0 )
+ ( $h5 & 0x40000000 ? 1 : 0 )
) << 30
| ( $sum & 0x3fffffff );
$h ^= ord( $s[$i] );
+ $h &= 0xffffffff;
}
return $h;
}
var $dpos;
/* initialized if cdb_findnext() returns 1 */
- var $dlen;
+ var $dlen;
+ /**
+ * @param $fileName string
+ */
function __construct( $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 "' . $fileName . '"' );
}
$this->findStart();
}
function close() {
- fclose( $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
$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( __METHOD__.': read from CDB file failed, file may be corrupted' );
}
return $buf;
}
/**
* Unpack an unsigned integer and throw an exception if it needs more than 31 bits
+ * @param $s
+ * @return
*/
protected function unpack31( $s ) {
$data = unpack( 'V', $s );
/**
* 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 . '"' );
+ throw new MWException( 'Unable to open CDB file for write "' . $fileName . '"' );
}
$this->hplist = array();
$this->numentries = 0;
}
}
+ /**
+ * @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();
- fclose( $this->handle );
+ if( isset($this->handle) ) {
+ fclose( $this->handle );
+ }
if ( wfIsWindows() && file_exists($this->realFileName) ) {
unlink( $this->realFileName );
}
unset( $this->handle );
}
+ /**
+ * @throws MWException
+ * @param $buf
+ */
protected function write( $buf ) {
$len = fwrite( $this->handle, $buf );
if ( $len !== strlen( $buf ) ) {
}
}
+ /**
+ * @throws MWException
+ * @param $len
+ */
protected function posplus( $len ) {
$newpos = $this->pos + $len;
if ( $newpos > 0x7fffffff ) {
$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->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'] );