file.php

<?php
/* ----------------------------------------------------------------------------
Copyright (c) 2007 Woody Gilk

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
---------------------------------------------------------------------------- */

class file {

	public static function split($filename, $output_dir = FALSE, $piece_size = 10)
	{
		// Find output dir
		$output_dir = ($output_dir == FALSE) ? pathinfo(realpath($filename), PATHINFO_DIRNAME) : realpath($output_dir);
		$output_dir = rtrim($output_dir, '/').'/';

		// Open files for writing
		$input_file = @fopen($filename, 'rb') or die($filename.' is not readable');

		// Change the piece size to bytes
		$piece_size = 1024 * 1024 * (int) $piece_size; // Size in bytes

		// Set up reading variables
		$read  = 0; // Number of bytes read
		$piece = 1; // Current piece
		$chunk = 1024 * 8; // Chunk size to read

		// Split the file
		while ( ! feof($input_file))
		{
			// Open a new piece
			$piece_name = $filename.'.'.str_pad($piece, 3, '0', STR_PAD_LEFT);
			$piece_open = @fopen($piece_name, 'wb+') or die('Could not write piece '.$piece_name);

			// Fill the current piece
			while ($read < $piece_size AND $data = fread($input_file, $chunk))
			{
				fwrite($piece_open, $data) or die('Could not write to open piece '.$piece_name);
				$read += $chunk;
			}
			// Close the current piece
			fclose($piece_open);
			print ".";
			// Prepare to open a new piece
			$read = 0;
			$piece++;
			// Make sure that piece is valid
			($piece < 999) or die('Maximum of 999 pieces exceeded, try a larger piece size');
		}
		// Close input file
		fclose($input_file);

		print "\nSplit $filename into ".($piece-1)." pieces\n";
	}

	public static function join($filename, $output = FALSE)
	{
		if ($output == FALSE)
			$output = $filename;

		// Set up reading variables
		$piece = 1; // Current piece
		$chunk = 1024 * 8; // Chunk size to read

		// Open output file
		$output_file = @fopen($output, 'wb+') or die('Could not open output file '.$output);

		// Read each piece
		while ($piece_open = @fopen(($piece_name = $filename.'.'.str_pad($piece, 3, '0', STR_PAD_LEFT)), 'rb'))
		{
			// Write the piece into the output file
			while( ! feof($piece_open))
			{
				fwrite($output_file, fread($piece_open, $chunk));
			}
			// Close the current piece
			fclose($piece_open);
			print ".";
			// Prepare for a new piece
			$piece++;
			// Make sure piece is valid
			($piece < 999) or die('Maximum of 999 pieces exceeded');
		}
		// Close the output file
		fclose($output_file);

		print "\nJoined ".($piece-1)." pieces into $output\n";
	}

} // End file Class