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Diffstat (limited to 'includes/utils/CdbPHP.php')
-rw-r--r-- | includes/utils/CdbPHP.php | 494 |
1 files changed, 0 insertions, 494 deletions
diff --git a/includes/utils/CdbPHP.php b/includes/utils/CdbPHP.php deleted file mode 100644 index 19d747a7..00000000 --- a/includes/utils/CdbPHP.php +++ /dev/null @@ -1,494 +0,0 @@ -<?php -/** - * 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 - */ - -/** - * Common functions for readers and writers - */ -class CdbFunctions { - /** - * 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 int $a - * @param int $b - * - * @return int - */ - public static function unsignedMod( $a, $b ) { - 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 int $a - * @param int $b - * @return int - */ - public static function unsignedShiftRight( $a, $b ) { - if ( $b == 0 ) { - return $a; - } - if ( $a & 0x80000000 ) { - return ( ( $a & 0x7fffffff ) >> $b ) | ( 0x40000000 >> ( $b - 1 ) ); - } else { - return $a >> $b; - } - } - - /** - * The CDB hash function. - * - * @param string $s - * - * @return int - */ - public static function hash( $s ) { - $h = 5381; - $len = strlen( $s ); - for ( $i = 0; $i < $len; $i++ ) { - $h5 = ( $h << 5 ) & 0xffffffff; - // Do a 32-bit sum - // Inlined here for speed - $sum = ( $h & 0x3fffffff ) + ( $h5 & 0x3fffffff ); - $h = - ( - ( $sum & 0x40000000 ? 1 : 0 ) - + ( $h & 0x80000000 ? 2 : 0 ) - + ( $h & 0x40000000 ? 1 : 0 ) - + ( $h5 & 0x80000000 ? 2 : 0 ) - + ( $h5 & 0x40000000 ? 1 : 0 ) - ) << 30 - | ( $sum & 0x3fffffff ); - $h ^= ord( $s[$i] ); - $h &= 0xffffffff; - } - - return $h; - } -} - -/** - * CDB reader class - */ -class CdbReaderPHP extends CdbReader { - /** The filename */ - protected $fileName; - - /* number of hash slots searched under this key */ - protected $loop; - - /* initialized if loop is nonzero */ - protected $khash; - - /* initialized if loop is nonzero */ - protected $kpos; - - /* initialized if loop is nonzero */ - protected $hpos; - - /* initialized if loop is nonzero */ - protected $hslots; - - /* initialized if findNext() returns true */ - protected $dpos; - - /* initialized if cdb_findnext() returns 1 */ - protected $dlen; - - /** - * @param string $fileName - * @throws CdbException - */ - public function __construct( $fileName ) { - $this->fileName = $fileName; - $this->handle = fopen( $fileName, 'rb' ); - if ( !$this->handle ) { - throw new CdbException( 'Unable to open CDB file "' . $this->fileName . '".' ); - } - $this->findStart(); - } - - public function close() { - if ( isset( $this->handle ) ) { - fclose( $this->handle ); - } - unset( $this->handle ); - } - - /** - * @param mixed $key - * @return bool|string - */ - public function get( $key ) { - // strval is required - if ( $this->find( strval( $key ) ) ) { - return $this->read( $this->dlen, $this->dpos ); - } else { - return false; - } - } - - /** - * @param string $key - * @param int $pos - * @return bool - */ - protected function match( $key, $pos ) { - $buf = $this->read( strlen( $key ), $pos ); - - return $buf === $key; - } - - protected function findStart() { - $this->loop = 0; - } - - /** - * @throws CdbException - * @param int $length - * @param int $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 CdbException( - 'Seek failed, file "' . $this->fileName . '" may be corrupted.' ); - } - - if ( $length == 0 ) { - return ''; - } - - $buf = fread( $this->handle, $length ); - if ( $buf === false || strlen( $buf ) !== $length ) { - throw new CdbException( - '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 string $s - * @throws CdbException - * @return mixed - */ - protected function unpack31( $s ) { - $data = unpack( 'V', $s ); - if ( $data[1] > 0x7fffffff ) { - throw new CdbException( - 'Error in CDB file "' . $this->fileName . '", integer too big.' ); - } - - return $data[1]; - } - - /** - * Unpack a 32-bit signed integer - * @param string $s - * @return int - */ - protected function unpackSigned( $s ) { - $data = unpack( 'va/vb', $s ); - - return $data['a'] | ( $data['b'] << 16 ); - } - - /** - * @param string $key - * @return bool - */ - protected function findNext( $key ) { - if ( !$this->loop ) { - $u = CdbFunctions::hash( $key ); - $buf = $this->read( 8, ( $u << 3 ) & 2047 ); - $this->hslots = $this->unpack31( substr( $buf, 4 ) ); - if ( !$this->hslots ) { - return false; - } - $this->hpos = $this->unpack31( substr( $buf, 0, 4 ) ); - $this->khash = $u; - $u = CdbFunctions::unsignedShiftRight( $u, 8 ); - $u = CdbFunctions::unsignedMod( $u, $this->hslots ); - $u <<= 3; - $this->kpos = $this->hpos + $u; - } - - while ( $this->loop < $this->hslots ) { - $buf = $this->read( 8, $this->kpos ); - $pos = $this->unpack31( substr( $buf, 4 ) ); - if ( !$pos ) { - return false; - } - $this->loop += 1; - $this->kpos += 8; - if ( $this->kpos == $this->hpos + ( $this->hslots << 3 ) ) { - $this->kpos = $this->hpos; - } - $u = $this->unpackSigned( substr( $buf, 0, 4 ) ); - if ( $u === $this->khash ) { - $buf = $this->read( 8, $pos ); - $keyLen = $this->unpack31( substr( $buf, 0, 4 ) ); - if ( $keyLen == strlen( $key ) && $this->match( $key, $pos + 8 ) ) { - // Found - $this->dlen = $this->unpack31( substr( $buf, 4 ) ); - $this->dpos = $pos + 8 + $keyLen; - - return true; - } - } - } - - return false; - } - - /** - * @param mixed $key - * @return bool - */ - protected function find( $key ) { - $this->findStart(); - - return $this->findNext( $key ); - } -} - -/** - * CDB writer class - */ -class CdbWriterPHP extends CdbWriter { - protected $hplist; - - protected $numentries; - - protected $pos; - - /** - * @param string $fileName - */ - public function __construct( $fileName ) { - $this->realFileName = $fileName; - $this->tmpFileName = $fileName . '.tmp.' . mt_rand( 0, 0x7fffffff ); - $this->handle = fopen( $this->tmpFileName, 'wb' ); - if ( !$this->handle ) { - $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 ) { - $this->throwException( 'fseek failed in file "' . $this->tmpFileName . '".' ); - } - } - - /** - * @param string $key - * @param string $value - */ - public function set( $key, $value ) { - if ( strval( $key ) === '' ) { - // DBA cross-check hack - return; - } - $this->addbegin( strlen( $key ), strlen( $value ) ); - $this->write( $key ); - $this->write( $value ); - $this->addend( strlen( $key ), strlen( $value ), CdbFunctions::hash( $key ) ); - } - - /** - * @throws CdbException - */ - public function close() { - $this->finish(); - if ( isset( $this->handle ) ) { - fclose( $this->handle ); - } - if ( $this->isWindows() && file_exists( $this->realFileName ) ) { - unlink( $this->realFileName ); - } - if ( !rename( $this->tmpFileName, $this->realFileName ) ) { - $this->throwException( 'Unable to move the new CDB file into place.' ); - } - unset( $this->handle ); - } - - /** - * @throws CdbException - * @param string $buf - */ - protected function write( $buf ) { - $len = fwrite( $this->handle, $buf ); - if ( $len !== strlen( $buf ) ) { - $this->throwException( 'Error writing to CDB file "' . $this->tmpFileName . '".' ); - } - } - - /** - * @throws CdbException - * @param int $len - */ - protected function posplus( $len ) { - $newpos = $this->pos + $len; - if ( $newpos > 0x7fffffff ) { - $this->throwException( - 'A value in the CDB file "' . $this->tmpFileName . '" is too large.' ); - } - $this->pos = $newpos; - } - - /** - * @param int $keylen - * @param int $datalen - * @param int $h - */ - protected function addend( $keylen, $datalen, $h ) { - $this->hplist[] = array( - 'h' => $h, - 'p' => $this->pos - ); - - $this->numentries++; - $this->posplus( 8 ); - $this->posplus( $keylen ); - $this->posplus( $datalen ); - } - - /** - * @throws CdbException - * @param int $keylen - * @param int $datalen - */ - protected function addbegin( $keylen, $datalen ) { - if ( $keylen > 0x7fffffff ) { - $this->throwException( 'Key length too long in file "' . $this->tmpFileName . '".' ); - } - if ( $datalen > 0x7fffffff ) { - $this->throwException( 'Data length too long in file "' . $this->tmpFileName . '".' ); - } - $buf = pack( 'VV', $keylen, $datalen ); - $this->write( $buf ); - } - - /** - * @throws CdbException - */ - protected function finish() { - // Hack for DBA cross-check - $this->hplist = array_reverse( $this->hplist ); - - // Calculate the number of items that will be in each hashtable - $counts = array_fill( 0, 256, 0 ); - foreach ( $this->hplist as $item ) { - ++$counts[255 & $item['h']]; - } - - // Fill in $starts with the *end* indexes - $starts = array(); - $pos = 0; - for ( $i = 0; $i < 256; ++$i ) { - $pos += $counts[$i]; - $starts[$i] = $pos; - } - - // Excessively clever and indulgent code to simultaneously fill $packedTables - // 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 ) { - $packedTables[--$starts[255 & $item['h']]] = $item; - } - - $final = ''; - for ( $i = 0; $i < 256; ++$i ) { - $count = $counts[$i]; - - // The size of the hashtable will be double the item count. - // The rest of the slots will be empty. - $len = $count + $count; - $final .= pack( 'VV', $this->pos, $len ); - - $hashtable = array(); - for ( $u = 0; $u < $len; ++$u ) { - $hashtable[$u] = array( 'h' => 0, 'p' => 0 ); - } - - // Fill the hashtable, using the next empty slot if the hashed slot - // is taken. - for ( $u = 0; $u < $count; ++$u ) { - $hp = $packedTables[$starts[$i] + $u]; - $where = CdbFunctions::unsignedMod( - CdbFunctions::unsignedShiftRight( $hp['h'], 8 ), $len ); - while ( $hashtable[$where]['p'] ) { - if ( ++$where == $len ) { - $where = 0; - } - } - $hashtable[$where] = $hp; - } - - // Write the hashtable - for ( $u = 0; $u < $len; ++$u ) { - $buf = pack( 'vvV', - $hashtable[$u]['h'] & 0xffff, - CdbFunctions::unsignedShiftRight( $hashtable[$u]['h'], 16 ), - $hashtable[$u]['p'] ); - $this->write( $buf ); - $this->posplus( 8 ); - } - } - - // Write the pointer array at the start of the file - rewind( $this->handle ); - if ( ftell( $this->handle ) != 0 ) { - $this->throwException( 'Error rewinding to start of file "' . $this->tmpFileName . '".' ); - } - $this->write( $final ); - } - - /** - * Clean up the temp file and throw an exception - * - * @param string $msg - * @throws CdbException - */ - protected function throwException( $msg ) { - if ( $this->handle ) { - fclose( $this->handle ); - unlink( $this->tmpFileName ); - } - throw new CdbException( $msg ); - } -} |