/* 函数名称:ipCity 参数说明:$userip——用户IP地址 函数功能:PHP通过IP地址判断用户所在城市 author:lee contact:xpsem2010@gmail.com */ function ipCity($userip) { //IP数据库路径,这里用的是QQ IP数据库 20110405 纯真版 $dat_path = 'QQWry.dat';
//判断IP地址是否有效 if(!ereg("^([0-9]{1,3}.){3}[0-9]{1,3}$", $userip)){ return 'IP Address Invalid'; } //打开IP数据库 if(!$fd = @fopen($dat_path, 'rb')){ return 'IP data file not exists or access denied'; } //explode函数分解IP地址,运算得出整数形结果 $userip = explode('.', $userip); $useripNum = $userip[0] * 16777216 + $userip[1] * 65536 + $userip[2] * 256 + $userip[3]; //获取IP地址索引开始和结束位置 $DataBegin = fread($fd, 4); $DataEnd = fread($fd, 4); $useripbegin = implode('', unpack('L', $DataBegin)); if($useripbegin < 0) $useripbegin += pow(2, 32); $useripend = implode('', unpack('L', $DataEnd)); if($useripend < 0) $useripend += pow(2, 32); $useripAllNum = ($useripend - $useripbegin) / 7 + 1; $BeginNum = 0; $EndNum = $useripAllNum; //使用二分查找法从索引记录中搜索匹配的IP地址记录 while($userip1num>$useripNum || $userip2num<$useripNum) { $Middle= intval(($EndNum + $BeginNum) / 2); //偏移指针到索引位置读取4个字节 fseek($fd, $useripbegin + 7 * $Middle); $useripData1 = fread($fd, 4); if(strlen($useripData1) < 4) { fclose($fd); return 'File Error'; } //提取出来的数据转换成长整形,如果数据是负数则加上2的32次幂 $userip1num = implode('', unpack('L', $useripData1)); if($userip1num < 0) $userip1num += pow(2, 32); //提取的长整型数大于我们IP地址则修改结束位置进行下一次循环 if($userip1num > $useripNum) { $EndNum = $Middle; continue; } //取完上一个索引后取下一个索引 $DataSeek = fread($fd, 3); if(strlen($DataSeek) < 3) { fclose($fd); return 'File Error'; } $DataSeek = implode('', unpack('L', $DataSeek.chr(0))); fseek($fd, $DataSeek); $useripData2 = fread($fd, 4); if(strlen($useripData2) < 4) { fclose($fd); return 'File Error'; } $userip2num = implode('', unpack('L', $useripData2)); if($userip2num < 0) $userip2num += pow(2, 32); //找不到IP地址对应城市 if($userip2num < $useripNum) { if($Middle == $BeginNum) { fclose($fd); return 'No Data'; } $BeginNum = $Middle; } } $useripFlag = fread($fd, 1); if($useripFlag == chr(1)) { $useripSeek = fread($fd, 3); if(strlen($useripSeek) < 3) { fclose($fd); return 'System Error'; } $useripSeek = implode('', unpack('L', $useripSeek.chr(0))); fseek($fd, $useripSeek); $useripFlag = fread($fd, 1); } if($useripFlag == chr(2)) { $AddrSeek = fread($fd, 3); if(strlen($AddrSeek) < 3) { fclose($fd); return 'System Error'; } $useripFlag = fread($fd, 1); if($useripFlag == chr(2)) { $AddrSeek2 = fread($fd, 3); if(strlen($AddrSeek2) < 3) { fclose($fd); return 'System Error'; } $AddrSeek2 = implode('', unpack('L', $AddrSeek2.chr(0))); fseek($fd, $AddrSeek2); } else { fseek($fd, -1, SEEK_CUR); } while(($char = fread($fd, 1)) != chr(0)) $useripAddr2 .= $char; $AddrSeek = implode('', unpack('L', $AddrSeek.chr(0))); fseek($fd, $AddrSeek); while(($char = fread($fd, 1)) != chr(0)) $useripAddr1 .= $char; } else { fseek($fd, -1, SEEK_CUR); while(($char = fread($fd, 1)) != chr(0)) $useripAddr1 .= $char; $useripFlag = fread($fd, 1); if($useripFlag == chr(2)) { $AddrSeek2 = fread($fd, 3); if(strlen($AddrSeek2) < 3) { fclose($fd); return 'System Error'; } $AddrSeek2 = implode('', unpack('L', $AddrSeek2.chr(0))); fseek($fd, $AddrSeek2); } else { fseek($fd, -1, SEEK_CUR); } while(($char = fread($fd, 1)) != chr(0)){ $useripAddr2 .= $char; } } fclose($fd); //返回IP地址对应的城市结果 if(preg_match('/http/i', $useripAddr2)) { $useripAddr2 = ''; } $useripaddr = "$useripAddr1 $useripAddr2"; $useripaddr = preg_replace('/CZ88.Net/is', '', $useripaddr); $useripaddr = preg_replace('/^s*/is', '', $useripaddr); $useripaddr = preg_replace('/s*$/is', '', $useripaddr); if(preg_match('/http/i', $useripaddr) || $useripaddr == '') { $useripaddr = 'No Data'; } return $useripaddr; } ?> |