<?php
/**
* Zend Framework
*
* LICENSE
*
* This source file is subject to the new BSD license that is bundled
* with this package in the file LICENSE.txt.
* It is also available through the world-wide-web at this URL:
* http://framework.zend.com/license/new-bsd
* If you did not receive a copy of the license and are unable to
* obtain it through the world-wide-web, please send an email
* to license@zend.com so we can send you a copy immediately.
*
* @category Zend
* @package Zend_Search_Lucene
* @subpackage Storage
* @copyright Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
/** Zend_Search_Lucene_Exception */
require_once 'Zend/Search/Lucene/Exception.php';
/**
* @category Zend
* @package Zend_Search_Lucene
* @subpackage Storage
* @copyright Copyright (c) 2005-2008 Zend Technologies USA Inc. (http://www.zend.com)
* @license http://framework.zend.com/license/new-bsd New BSD License
*/
abstract class Zend_Search_Lucene_Storage_File
{
/**
* Reads $length number of bytes at the current position in the
* file and advances the file pointer.
*
* @param integer $length
* @return string
*/
abstract protected function _fread($length=1);
/**
* Sets the file position indicator and advances the file pointer.
* The new position, measured in bytes from the beginning of the file,
* is obtained by adding offset to the position specified by whence,
* whose values are defined as follows:
* SEEK_SET - Set position equal to offset bytes.
* SEEK_CUR - Set position to current location plus offset.
* SEEK_END - Set position to end-of-file plus offset. (To move to
* a position before the end-of-file, you need to pass a negative value
* in offset.)
* Upon success, returns 0; otherwise, returns -1
*
* @param integer $offset
* @param integer $whence
* @return integer
*/
abstract public function seek($offset, $whence=SEEK_SET);
/**
* Get file position.
*
* @return integer
*/
abstract public function tell();
/**
* Flush output.
*
* Returns true on success or false on failure.
*
* @return boolean
*/
abstract public function flush();
/**
* Writes $length number of bytes (all, if $length===null) to the end
* of the file.
*
* @param string $data
* @param integer $length
*/
abstract protected function _fwrite($data, $length=null);
/**
* Lock file
*
* Lock type may be a LOCK_SH (shared lock) or a LOCK_EX (exclusive lock)
*
* @param integer $lockType
* @return boolean
*/
abstract public function lock($lockType, $nonBlockinLock = false);
/**
* Unlock file
*/
abstract public function unlock();
/**
* Reads a byte from the current position in the file
* and advances the file pointer.
*
* @return integer
*/
public function readByte()
{
return ord($this->_fread(1));
}
/**
* Writes a byte to the end of the file.
*
* @param integer $byte
*/
public function writeByte($byte)
{
return $this->_fwrite(chr($byte), 1);
}
/**
* Read num bytes from the current position in the file
* and advances the file pointer.
*
* @param integer $num
* @return string
*/
public function readBytes($num)
{
return $this->_fread($num);
}
/**
* Writes num bytes of data (all, if $num===null) to the end
* of the string.
*
* @param string $data
* @param integer $num
*/
public function writeBytes($data, $num=null)
{
$this->_fwrite($data, $num);
}
/**
* Reads an integer from the current position in the file
* and advances the file pointer.
*
* @return integer
*/
public function readInt()
{
$str = $this->_fread(4);
return ord($str[0]) << 24 |
ord($str[1]) << 16 |
ord($str[2]) << 8 |
ord($str[3]);
}
/**
* Writes an integer to the end of file.
*
* @param integer $value
*/
public function writeInt($value)
{
settype($value, 'integer');
$this->_fwrite( chr($value>>24 & 0xFF) .
chr($value>>16 & 0xFF) .
chr($value>>8 & 0xFF) .
chr($value & 0xFF), 4 );
}
/**
* Returns a long integer from the current position in the file
* and advances the file pointer.
*
* @return integer
* @throws Zend_Search_Lucene_Exception
*/
public function readLong()
{
$str = $this->_fread(8);
/**
* Check, that we work in 64-bit mode.
* fseek() uses long for offset. Thus, largest index segment file size in 32bit mode is 2Gb
*/
if (PHP_INT_SIZE > 4) {
return ord($str[0]) << 56 |
ord($str[1]) << 48 |
ord($str[2]) << 40 |
ord($str[3]) << 32 |
ord($str[4]) << 24 |
ord($str[5]) << 16 |
ord($str[6]) << 8 |
ord($str[7]);
} else {
if ((ord($str[0]) != 0) ||
(ord($str[1]) != 0) ||
(ord($str[2]) != 0) ||
(ord($str[3]) != 0) ||
((ord($str[0]) & 0x80) != 0)) {
throw new Zend_Search_Lucene_Exception('Largest supported segment size (for 32-bit mode) is 2Gb');
}
return ord($str[4]) << 24 |
ord($str[5]) << 16 |
ord($str[6]) << 8 |
ord($str[7]);
}
}
/**
* Writes long integer to the end of file
*
* @param integer $value
* @throws Zend_Search_Lucene_Exception
*/
public function writeLong($value)
{
/**
* Check, that we work in 64-bit mode.
* fseek() and ftell() use long for offset. Thus, largest index segment file size in 32bit mode is 2Gb
*/
if (PHP_INT_SIZE > 4) {
settype($value, 'integer');
$this->_fwrite( chr($value>>56 & 0xFF) .
chr($value>>48 & 0xFF) .
chr($value>>40 & 0xFF) .
chr($value>>32 & 0xFF) .
chr($value>>24 & 0xFF) .
chr($value>>16 & 0xFF) .
chr($value>>8 & 0xFF) .
chr($value & 0xFF), 8 );
} else {
if ($value > 0x7FFFFFFF) {
throw new Zend_Search_Lucene_Exception('Largest supported segment size (for 32-bit mode) is 2Gb');
}
$this->_fwrite( "\x00\x00\x00\x00" .
chr($value>>24 & 0xFF) .
chr($value>>16 & 0xFF) .
chr($value>>8 & 0xFF) .
chr($value & 0xFF), 8 );
}
}
/**
* Returns a variable-length integer from the current
* position in the file and advances the file pointer.
*
* @return integer
*/
public function readVInt()
{
$nextByte = ord($this->_fread(1));
$val = $nextByte & 0x7F;
for ($shift=7; ($nextByte & 0x80) != 0; $shift += 7) {
$nextByte = ord($this->_fread(1));
$val |= ($nextByte & 0x7F) << $shift;
}
return $val;
}
/**
* Writes a variable-length integer to the end of file.
*
* @param integer $value
*/
public function writeVInt($value)
{
settype($value, 'integer');
while ($value > 0x7F) {
$this->_fwrite(chr( ($value & 0x7F)|0x80 ));
$value >>= 7;
}
$this->_fwrite(chr($value));
}
/**
* Reads a string from the current position in the file
* and advances the file pointer.
*
* @return string
*/
public function readString()
{
$strlen = $this->readVInt();
if ($strlen == 0) {
return '';
} else {
/**
* This implementation supports only Basic Multilingual Plane
* (BMP) characters (from 0x0000 to 0xFFFF) and doesn't support
* "supplementary characters" (characters whose code points are
* greater than 0xFFFF)
* Java 2 represents these characters as a pair of char (16-bit)
* values, the first from the high-surrogates range (0xD800-0xDBFF),
* the second from the low-surrogates range (0xDC00-0xDFFF). Then
* they are encoded as usual UTF-8 characters in six bytes.
* Standard UTF-8 representation uses four bytes for supplementary
* characters.
*/
$str_val = $this->_fread($strlen);
for ($count = 0; $count < $strlen; $count++ ) {
if (( ord($str_val[$count]) & 0xC0 ) == 0xC0) {
$addBytes = 1;
if (ord($str_val[$count]) & 0x20 ) {
$addBytes++;
// Never used. Java2 doesn't encode strings in four bytes
if (ord($str_val[$count]) & 0x10 ) {
$addBytes++;
}
}
$str_val .= $this->_fread($addBytes);
$strlen += $addBytes;
// Check for null character. Java2 encodes null character
// in two bytes.
if (ord($str_val[$count]) == 0xC0 &&
ord($str_val[$count+1]) == 0x80 ) {
$str_val[$count] = 0;
$str_val = substr($str_val,0,$count+1)
. substr($str_val,$count+2);
}
$count += $addBytes;
}
}
return $str_val;
}
}
/**
* Writes a string to the end of file.
*
* @param string $str
* @throws Zend_Search_Lucene_Exception
*/
public function writeString($str)
{
/**
* This implementation supports only Basic Multilingual Plane
* (BMP) characters (from 0x0000 to 0xFFFF) and doesn't support
* "supplementary characters" (characters whose code points are
* greater than 0xFFFF)
* Java 2 represents these characters as a pair of char (16-bit)
* values, the first from the high-surrogates range (0xD800-0xDBFF),
* the second from the low-surrogates range (0xDC00-0xDFFF). Then
* they are encoded as usual UTF-8 characters in six bytes.
* Standard UTF-8 representation uses four bytes for supplementary
* characters.
*/
// convert input to a string before iterating string characters
settype($str, 'string');
$chars = $strlen = strlen($str);
$containNullChars = false;
for ($count = 0; $count < $strlen; $count++ ) {
/**
* String is already in Java 2 representation.
* We should only calculate actual string length and replace
* \x00 by \xC0\x80
*/
if ((ord($str[$count]) & 0xC0) == 0xC0) {
$addBytes = 1;
if (ord($str[$count]) & 0x20 ) {
$addBytes++;
// Never used. Java2 doesn't encode strings in four bytes
// and we dont't support non-BMP characters
if (ord($str[$count]) & 0x10 ) {
$addBytes++;
}
}
$chars -= $addBytes;
if (ord($str[$count]) == 0 ) {
$containNullChars = true;
}
$count += $addBytes;
}
}
if ($chars < 0) {
throw new Zend_Search_Lucene_Exception('Invalid UTF-8 string');
}
$this->writeVInt($chars);
if ($containNullChars) {
$this->_fwrite(str_replace($str, "\x00", "\xC0\x80"));
} else {
$this->_fwrite($str);
}
}
/**
* Reads binary data from the current position in the file
* and advances the file pointer.
*
* @return string
*/
public function readBinary()
{
return $this->_fread($this->readVInt());
}
}