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PHK Manager |  |
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| Size: | 6627 |
| Storage flags: |
<?php
//=============================================================================
//
// Copyright Francois Laupretre <phk@tekwire.net>
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//=============================================================================
/**
* @copyright Francois Laupretre <phk@tekwire.net>
* @license http://www.apache.org/licenses/LICENSE-2.0 Apache License, V 2.0
* @category PHK
* @package PHK
*///==========================================================================
namespace PHK {
if (!class_exists('PHK\PkgFile',false))
{
//=============================================================================
/**
* Contains the code to physically access PHK package files.
*
* API status: Private
* Included in the PHK PHP runtime: Yes
* Implemented in the extension: No
*///==========================================================================
class PkgFile
{
private $fp=null;
private $path;
private $size;
private $open_count=0;
private $keep_open_flag;
//------
// Special case : keep sub-PHKs open (in stream wrapper memory)
public function __construct($path,$flags)
{
$this->setParams($path,$flags);
if (($this->size=filesize($path))===false)
throw new \Exception($path.': Cannot get file size');
}
//------
public function setParams($path,$flags)
{
$this->path=$path;
$this->keep_open_flag=\PHK\Mgr::isPhkUri($path);
}
//---
public function __sleep()
{
return array('size');
}
//------
public function __destruct()
{
$this->reallyClose();
}
//------
private function reallyClose()
{
if (!is_null($this->fp))
{
fclose($this->fp);
$this->fp=null;
$this->open_count=0;
}
}
//------
// Open in read-only mode. Maintains a count for close(), throws exceptions,
// and force 'b' mode (for Windows).
// Called from self or \PHK\PkgFileSpace only
public function _open()
{
if (is_null($this->fp))
{
if (!($this->fp=fopen($this->path,'rb',false))) //-- 'b' mode is for Windows
throw new \Exception($this->path.': Cannot open for reading');
$this->open_count=1;
}
else $this->open_count++;
}
//-----
// fclose() the file pointer. Maintains an open count.
// Called from self or \PHK\PkgFileSpace only
public function _close()
{
$this->open_count--;
if (($this->open_count <= 0) && (!$this->keep_open_flag)) $this->reallyClose();
}
//-----
// Same as PHP fread() but reads any size, throws exceptions, and checks size
// I don't use stream_get_contents() because, sometimes, it crashes
// on Windows (detected with PHP 5.1.4).
private function read($size)
{
$data='';
$nb_chunks=intval($size/8192);
$rest=$size % 8192;
\PHK\Tools\Util::disableMQR();
while ($nb_chunks > 0)
{
$data .= $this->readChunk(8192);
$nb_chunks--;
}
if ($rest) $data .= $this->readChunk($rest);
\PHK\Tools\Util::restoreMQR();
return $data;
}
//-----
// Read up to 8192 bytes
private function readChunk($size)
{
$buf=fread($this->fp,$size);
if ($buf===false) throw new \Exception('Cannot read');
if (($bsize=strlen($buf))!=$size)
throw new \Exception("Short read ($bsize/$size)");
return $buf;
}
//-----
// Reads a block from file.
// Called only from \PHK\PkgFileSpace. So:
// - we don't need to check bounds,
// - we don't provide default args,
// - we are sure that size is > 0
public function _readBlock($offset,$size)
{
try
{
$this->_open();
if (fseek($this->fp,$offset,SEEK_SET) == -1)
throw new \Exception('Cannot seek');
$buf=$this->read($size);
$this->_close(); // At the end. Everything before can raise an exception
} // and we don't want to close it twice
catch (\Exception $e)
{
$this->_close();
throw new \Exception($e->getMessage());
}
return $buf;
}
//------
public function size()
{
return $this->size;
}
//------
public function path()
{
return $this->path;
}
} // End of class PHK\PkgFile
//-------------------------
} // End of class_exists
//=============================================================================
if (!class_exists('PHK\PkgFileSpace',false))
{
//-------------------------
class PkgFileSpace
{
public $file; // underlying \PHK\PkgFile object
private $offset;
private $size;
//------
// Two possibles syntaxes :
// new \PHK\PkgFileSpace(string $path,int $flags) : creates a first space for a file
// new \PHK\PkgFileSpace(PkgFileSpace $parent, int $offset, int $size) :
// creates a subspace inside an existing FileSpace.
public function __construct($arg1,$arg2,$size=null)
{
if (is_string($arg1))
{
$this->file=new \PHK\PkgFile($arg1,$arg2);
$this->offset=0;
$this->size=$this->file->size();
}
else
{
if ((!($arg1 instanceof self))
|| (!is_numeric($arg2))
|| (!is_numeric($size))
|| ($arg2 < 0)
|| (($arg2+$size) > $arg1->size))
throw new \Exception("PkgFileSpace: cannot create - invalid arguments");
$this->file=$arg1->file;
$this->offset=$arg1->offset + $arg2;
$this->size=$size;
}
}
//------
// Default args so that readBlock() without args returns the whole filespace
public function readBlock($offset=0,$size=null)
{
//\PHK\Tools\Util::trace("Starting PkgFileSpace::read_block - offset=$offset - size=$size");//TRACE
if (is_null($size)) $size=$this->size-$offset; // Read up to the end
if (($offset<0)||($size<0)||($offset+$size>$this->size))
throw new \Exception('PkgFileSpace: Read out of bound');
if ($size==0) return '';
$data=$this->file->_readBlock($this->offset+$offset,$size);
//\PHK\Tools\Util::trace("Ending PkgFileSpace::read_block");//TRACE
return $data;
}
//------
// Used to force the file to remain open temporarily
public function open()
{
$this->file->_open();
}
//------
public function close()
{
$this->file->_close();
}
//------
public function size()
{
return $this->size;
}
//------
// Returns path of underlying file (can be a PHK URI)
public function path()
{
return $this->file->path();
}
//---
} // End of class
//===========================================================================
} // End of class_exists
//===========================================================================
} // End of namespace
//===========================================================================
?>