zip.class.php

一款文件上传程序

<?php
if ( !function_exists ( 'gzinflate' ) ) exit ( 'Zip.class.php cannot be used because the zlib library is not available.' );

class zip
{
	var $_fp;
	var $_cdr;

	function zip ( )
	{
		$this->_fp = false;
		$this->_cdr = array();
	}

	function open ( $f )
	{
		if ( false === ( $this->_fp = @fopen ( $f, 'rb' ) ) ) return false;
		$this->_getCDR();
		if ( !is_array ( $this->_cdr ) || !count ( $this->_cdr ) ) return false;
		return true;
	}

	function getFile ( )
	{
		list ( $k, $v ) = each ( $this->_cdr );
		if ( is_array ( $v ) ) return $this->_getEntry ( $v['rel_offset'] );
		return false;
	}

	function _getCDR ( )
	{
		fseek ( $this->_fp, -22, SEEK_END );
		$stop_pos = ftell ( $this->_fp );
		$d = fread ( $this->_fp, 22 );
		if ( strlen ( $d ) != 22 ) return false;
		$cdr = unpack ( 'Ncdr_sig/nignore1/nignore2/nignore3/nignore4/Vcdr_size/Vdisk_num/ncomment_len', $d );
		if ( $cdr['cdr_sig'] !== 0x504b0506 ) return false;
		fseek ( $this->_fp, - ( $cdr['cdr_size'] + 22 ), SEEK_END );

		while ( ftell ( $this->_fp ) < $stop_pos )
		{
			// get all file headers
			$data = fread ( $this->_fp, 46 );
			if ( strlen ( $data ) != 46 ) return false;
			$fh = unpack ( 'Vcfh_sig/vversion_made_by/vv_extract/ngen_flag/vcomppression_method/vmod_time/vmode_date/Ncrc32/Vcompressed_size/Vuncompressed_size/vfilename_len/nxtr_len/nfilecomment_len/ndisk_num_start/ninternal_attrib/Vext_attrib/Vrel_offset', $data );
			if ( !is_array ( $fh ) || $fh['cfh_sig'] != 33639248 ) return false;
			$fh['filename'] = $fh['filename_len'] ? fread ( $this->_fp, $fh['filename_len'] ) : $fh['filename_len'];
			$fh['extra']    = $fh['xtr_len'] ? fread ( $this->_fp, $fh['xtr_len'] ) : '';
			$fh['comments'] = $fh['filecomment_len'] ? fread ( $this->_fp, $fh['filecomment_len'] ) : '';
			$this->_cdr[] = $fh;
		}
		return true;
	}

	function _getEntry ( $lfh_offset )
	{
		fseek ( $this->_fp, $lfh_offset, SEEK_SET );
		$lfh = unpack ( 'Vheader_sig/Sversion_extract/Sgen_purpose/Scompression_method/Slast_mod_time/Slast_mod_date/Vcrc_32/Vcompressed_size/Vuncompressed_size/Sfile_name_length/Sextra_field_length', fread ( $this->_fp, 30 ) );
		$lfh['name'] = $lfh['file_name_length'] ? fread ( $this->_fp, $lfh['file_name_length'] ) : '';
		$lfh['extra_field'] = $lfh['extra_field_length'] ? fread ( $this->_fp,$lfh['extra_field_length'] ) : '';
		if ( $lfh['compression_method'] == 8 ) $file_content = $lfh['compressed_size'] ? @gzinflate ( fread ( $this->_fp, $lfh['compressed_size'] ) ) : '';
		elseif ( $lfh['compression_method'] == 0 ) $file_content = $lfh['compressed_size'] ? fread ( $this->_fp, $lfh['compressed_size'] ) : '';
		else return false;
		$ldd = $lfh['gen_purpose'] & 8 ? unpack ( 'Vcrc_32/Vcompressed_size/Vuncompressed_size', fread ( $this->_fp, 12 ) ) : '';
		return array ( 'name' => $lfh['name'], 'size' => $lfh['uncompressed_size'], 'content' => &$file_content );
	}

	function close ( )
	{
		@fclose ( $this->_fp );
	}
}
?>