[PHP] PHP调用IMAP协议读取邮件类库

socket.php 为连接socket的类库

imap.php 基于socket的imap协议封装

test.php 进行测试

require_once 'socket.php';
require_once 'imap.php';
$imap=new Sina_Mail_Net_Imap("imap.sina.net:143",30,30);
$imap->capability();
$imap->id(array(
    'name'          => 'SinaMail OtherMail Client',
    'version'       => '1',
    'os'            => 'SinaMail OtherMail',
    'os-version'    => '1.0',
));
$imap->login("xxxx@xxxxx","xxxx");
$folders=$imap->getList('', '*');
var_dump($folders);
$status = $imap->select('SENT');
var_dump($status);
$ls = $imap->fetch(array(), array('uid', 'internaldate', 'rfc822.size'));




foreach($ls as $k=>$i){
    $info=$imap->fetch(array($k), array('rfc822'));
}

 

imap.php

<?php
class Sina_Mail_Net_Imap {
    const MAX_READ_SIZE = 100000000;
    const PATTERN_REQUEST_STRING_SEQUENCE   = '/{\d+}/';
    const PATTERN_RESPONSE_STRING_SEQUENCE  = '/{(\d+)}$/';
    const SEQUENCE_PARAM_NAME   = '[]';
    const PARTIAL_PARAM_NAME    = '<>';
    const PARAM_NO          = 1;
    const PARAM_SINGLE      = 2;
    const PARAM_PAIR        = 4;
    const PARAM_LIST        = 8;
    const PARAM_STRING      = 16;
    const PARAM_NUMBER      = 32;
    const PARAM_DATE        = 64;
    const PARAM_FLAG        = 128;
    const PARAM_SEQUENCE    = 256;
    const PARAM_SEARCH      = 512;
    const PARAM_BODY        = 1024;
    const PARAM_PARTIAL     = 2048;
    const PARAM_EXCLUSIVE   = 4096;
    private static $statusKeywords = array(
        'MESSAGES'      => self::PARAM_NO,
        'RECENT'        => self::PARAM_NO,
        'UIDNEXT'       => self::PARAM_NO,
        'UIDVALIDITY'   => self::PARAM_NO,
        'UNSEEN'        => self::PARAM_NO,
    );
    private static $searchKeywords = array(
        'ALL'           => self::PARAM_NO,
        'ANSWERED'      => self::PARAM_NO,
        'BCC'           => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'BEFORE'        => 66, // self::PARAM_SINGLE | self::PARAM_DATE,
        'BODY'          => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'CC'            => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'DELETED'       => self::PARAM_NO,
        'DRAFT'         => self::PARAM_NO,
        'FLAGGED'       => self::PARAM_NO,
        'FROM'          => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'HEADER'        => 20, // self::PARAM_PAIR | self::PARAM_STRING,
        'KEYWORD'       => 130, // self::PARAM_SINGLE | self::PARAM_FLAG,
        'LARGER'        => 34, // self::PARAM_SINGLE | self::PARAM_NUMBER,
        'NEW'           => self::PARAM_NO,
        'NOT'           => 514, // self::PARAM_SINGLE | self::PARAM_SEARCH,
        'OLD'           => self::PARAM_NO,
        'ON'            => 66, // self::PARAM_SINGLE | self::PARAM_DATE,
        'OR'            => 516, // self::PARAM_PAIR | self::PARAM_SEARCH,
        'RECENT'        => self::PARAM_NO,
        'SEEN'          => self::PARAM_NO,
        'SENTBEFORE'    => 66, // self::PARAM_SINGLE | self::PARAM_DATE,
        'SENTON'        => 66, // self::PARAM_SINGLE | self::PARAM_DATE,
        'SENTSINCE'     => 66, // self::PARAM_SINGLE | self::PARAM_DATE,
        'SINCE'         => 66, // self::PARAM_SINGLE | self::PARAM_DATE,
        'SMALLER'       => 34, // self::PARAM_SINGLE | self::PARAM_NUMBER,
        'SUBJECT'       => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'TEXT'          => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'TO'            => 18, // self::PARAM_SINGLE | self::PARAM_STRING,
        'UID'           => 258, // self::PARAM_SINGLE | self::PARAM_SEQUENCE,
        'UNANSWERED'    => self::PARAM_NO,
        'UNDELETED'     => self::PARAM_NO,
        'UNDRAFT'       => self::PARAM_NO,
        'UNFLAGGED'     => self::PARAM_NO,
        'UNKEYWORD'     => 130, // self::PARAM_SINGLE | self::PARAM_FLAG,
        'UNSEEN'        => self::PARAM_NO,
    );
    private static $fetchKeywords = array(
        'ALL'           => 4097, // self::PARAM_NO | self::PARAM_EXCLUSIVE,
        'FAST'          => 4097, // self::PARAM_NO | self::PARAM_EXCLUSIVE,
        'FULL'          => 4097, // self::PARAM_NO | self::PARAM_EXCLUSIVE,
        'BODY'          => 3075, // self::PARAM_NO | self::PARAM_SINGLE | self::PARAM_BODY | self::PARAM_PARTIAL,
        'BODY.PEEK'     => 3074, // self::PARAM_SINGLE | self::PARAM_BODY | self::PARAM_PARTIAL,
        'BODYSTRUCTURE' => self::PARAM_NO,
        'ENVELOPE'      => self::PARAM_NO,
        'FLAGS'         => self::PARAM_NO,
        'INTERNALDATE'  => self::PARAM_NO,
        'RFC822'        => self::PARAM_NO,
        'RFC822.HEADER' => self::PARAM_NO,
        'RFC822.SIZE'   => self::PARAM_NO,
        'RFC822.TEXT'   => self::PARAM_NO,
        'UID'           => self::PARAM_NO,
    );
    private $sock = null;
    private $timeout = 120;
    private $ts = 0;
    private $tagName = 'A';
    private $tagId = 0;
    private $capabilities = array();
    private $folders = array();
    private $currentFolder = null;
    private $currentCommand = null;
    private $lastSend = '';
    private $lastRecv = '';
    public function __construct($uri, $timeout = null, $connTimeout = null) {
        $this->sock = new Socket($uri, $timeout);        
//        $t = intval($timeout);
//        if ($t > 0) {
//            $this->timeout = $t;
//        }
        $this->connect($connTimeout);        
    }
    public function __destruct() {
    }

    public function connect($timeout) {        
        $this->sock->connect($timeout);        
        $this->getResponse();
    }
    
    public function capability() {
        $res = $this->request('capability');
        if (isset($res[0][0]) && $res[0][0] == '*' &&
            isset($res[0][1]) && strcasecmp($res[0][1], 'capability') == 0) {
            for ($i = 2, $n = count($res[0]); $i < $n; ++$i) {
                $this->capabilities[strtoupper($res[0][$i])] = true;
            }
        }        
    }
    
    public function id($data) {
        if (isset($this->capabilities['ID'])) {            
            $this->request('id', array($data));            
        }        
    }
    public function login($username, $password) {
        try {
            $this->request('login', array($username, $password));
        } catch (Exception $ex) {
            throw new Exception($ex->getMessage(), $ex->getCode());
        }
    }
    
    public function logout() {
        $this->request('logout');        
    }
    
    public function getList($reference = '', $wildcard = '') {
        $res = $this->request('list', array($reference, $wildcard));
        foreach ($res as &$r) {
            if (isset($r[0]) && $r[0] == '*' && 
                isset($r[1]) && strcasecmp($r[1], 'list') == 0 && 
                isset($r[4])) {
                $this->folders[$r[4]] = array(
                    'id'    => $r[4],
                    'name'  => mb_convert_encoding($r[4], 'UTF-8', 'UTF7-IMAP'),
                    'path'  => $r[3],
                    'attr'  => $r[2],
                );
            }
        }
        return $this->folders;
    }
    
    public function status($folder, $data) {
        $args = $this->formatArgsForCommand($data, self::$statusKeywords);
        $res = $this->request('status', array($folder, $args));
        $status = array();
        if (!empty($res)) {            
            foreach ($res as &$r) {
                if (isset($r[0]) && $r[0] == '*' && 
                    isset($r[1]) && strcasecmp($r[1], 'status') == 0 && 
                    isset($r[3]) && is_array($r[3])) {
                    for ($i = 0, $n = count($r[3]); $i < $n; $i += 2) {
                        $status[$r[3][$i]] = $r[3][$i + 1];
                    }
                }
            }
        }
        return $status;
    }
    public function select($folder) {
        $res = $this->request('select', array($folder));
        $status = array();
        if (!empty($res)) {
            foreach ($res as $r) {
                if (isset($r[0]) && $r[0] == '*') {
                    if (isset($r[1]) && isset($r[2])) {
                        if (strcasecmp($r[1], 'ok') == 0 && is_array($r[2])) {
                            for ($i = 0, $n = count($i); $i < $n; $i += 2) {
                                $status[$r[2][$i]] = $r[2][$i + 1];
                            }
                        } elseif (ctype_digit($r[1])) {
                            $status[$r[2]] = $r[1];
                        } else {
                            $status[$r[1]] = $r[2];
                        }    
                    }
                }
            }
        }
        $this->currentFolder = $folder;
        return $status;
    }
    public function search($data) {     
        $args = $this->formatArgsForCommand($data, self::$searchKeywords, true);                
        $res = $this->request('search', $args);
        $ls = array();
        foreach ($res as &$r) {
            if (isset($r[0]) && $r[0] == '*' && 
                isset($r[1]) && strcasecmp($r[1], 'search') == 0) {
                for ($i = 2, $n = count($r); $i < $n; ++$i) {
                    $ls[] = $r[$i];
                }
            }
        }
        return $ls;
    }
    public function fetch($seq, $data) {                        
        $seqStr = $this->formatSequence($seq);        
        $args = $this->formatArgsForCommand($data, self::$fetchKeywords);                                
        $res = $this->request('fetch', array($seqStr, $args));
//        var_dump($res);
        $ls = array();
        foreach ($res as &$r) {
            if (isset($r[0]) && $r[0] == '*' &&
                isset($r[1]) && is_numeric($r[1]) && 
                isset($r[2]) && strcasecmp($r[2], 'fetch') == 0 &&
                isset($r[3]) && is_array($r[3])) {
                $a = array();
                for ($i = 0, $n = count($r[3]); $i < $n; $i += 2) {
                    $key = $r[3][$i];
                    if (((strcasecmp($key, 'BODY') == 0 && isset($args['BODY']) && is_array($args['BODY'])) || 
                         (strcasecmp($key, 'BODY.PEEK') == 0 && isset($args['BODY.PEEK']) && is_array($args['BODY.PEEK']))) && 
                        is_array($r[3][$i + 1])) {
                        $key = trim($this->formatRequestArray(array($key => $r[3][$i + 1]), $placeHolder, 0), '()');
                        $i++;
                    } else {
                        $key = $r[3][$i];
                    }
                    $a[$key] = $r[3][$i + 1];
                }
                if (!empty($a)) {
                    $ls[$r[1]] = $a;
                }
            }
        }
        return $ls;
    }
    private function nextTag() {
        $this->tagId++;
        return sprintf('%s%d', $this->tagName, $this->tagId);
    }
    private function request($cmd, $args = array()) {                
        $this->currentCommand = strtoupper(trim($cmd));
        $tag = $this->nextTag();
        $req = $tag . ' ' . $this->currentCommand;
        
        // 格式化参数列表
        $strSeqList = array();
        if (is_array($args)) {
            $argStr = $this->formatRequestArray($args, $strSeqList);                
        } else {                
            $argStr = $this->formatRequestString($args, $strSeqList);
        }
        //$argStr = $this->makeRequest($args, $strSeqList);
        $subReqs = array();
        if (isset($argStr[0])) {
            $req .= ' ' . $argStr;
            // 如果参数中包括需要序列化的数据，根据序列化标识{length}将命令拆分成多条
            if (!empty($strSeqList) && preg_match_all(self::PATTERN_REQUEST_STRING_SEQUENCE, $req, $matches, PREG_OFFSET_CAPTURE)) {
                $p = 0;
                foreach ($matches[0] as $m) {
                    $e = $m[1] + strlen($m[0]);
                    $subReqs[] = substr($req, $p, $e - $p);                    
                    $p = $e;
                }
                $subReqs[] = substr($req, $p);
                // 校验序列化标识与需要序列化的参数列表数量是否一致
                if (count($subReqs) != count($strSeqList) + 1) {
                    $subReqs = null;
                }
            }
        }
                
        if (empty($subReqs)) {
            // 处理单条命令
            $this->sock->writeLine($req);
            $this->lastSend = $req;        
            $res = $this->getResponse($tag);
        } else {            
            // 处理多条命令
            $this->lastSend = '';
            foreach ($subReqs as $id => $req) {
                $this->sock->writeLine($req);                          
                $this->lastSend .= $req;
                $res = $this->getResponse($tag);                
                if (isset($res[0][0]) && $res[0][0] == '+') {
                    $this->sock->write($strSeqList[$id]);                
                    $this->lastSend .= "\r\n" . $strSeqList[$id];
                } else {
                    // 如果服务器端返回其他相应，则定制后续执行
                    break;
                }
            }                
        }
        return $res;
    }
        
    private function formatRequestString($s, &$strSeqList) {
        $s = trim($s);
        $needQuote = false;
        if (!isset($s[0])) {
            $needQuote = true;
        } elseif ($this->currentCommand == 'ID') {    
            $needQuote = true;
        } else {
            // 参数包含多行时，需要进行序列化
            if (strpos($s, "\r") !== false || strpos($s, "\n") !== false) {                
                $strSeqList[] = $s;
                $s = sprintf('{%d}', strlen($s));
            } else {
                // 参数包含双引号或空格时，需要将使用双引号括起来
                if (strpos($s, '"') !== false) {
                    $s = addcslashes($s, '"');
                    $needQuote = true;
                }
                if (strpos($s, ' ') !== false) {
                    $needQuote = true;
                }
            }
        }
        if ($needQuote) {
            return sprintf('"%s"', $s);
        } else {
            return $s;
        }
    }
    private function formatRequestArray($arr, &$strSeqList, $level = -1) {
        $a = array();
        foreach ($arr as $k => $v) {
            $isBody = false;
            $supportPartial = false;
            $partialStr = '';
            if ($this->currentCommand == 'FETCH') {
                // 识别是否body命令，是否可以包含<partial>
                $kw = strtoupper($k);            
                if (isset(self::$fetchKeywords[$kw]) && (self::$fetchKeywords[$kw] & self::PARAM_BODY) > 0) {
                    $isBody = true;
                }
                if (isset(self::$fetchKeywords[$kw]) && (self::$fetchKeywords[$kw] & self::PARAM_PARTIAL) > 0) {
                    $supportPartial = true;
                }
            }                        
            if (is_array($v)) {                        
                if ($supportPartial && isset($v[self::PARTIAL_PARAM_NAME]) && is_array($v[self::PARTIAL_PARAM_NAME])) {                    
                    // 处理包含<partial>的命令
                    foreach ($v[self::PARTIAL_PARAM_NAME] as $spos => $mlen) {
                        $partialStr =  sprintf('<%d.%d>', $spos, $mlen);
                    }                    
                    unset($v[self::PARTIAL_PARAM_NAME]);
                }
                $s = $this->formatRequestArray($v, $strSeqList, $level + 1);
            } else {
                $s = $this->formatRequestString($v, $strSeqList);
            }            
            if (!is_numeric($k)) {
                // 字典方式需要包含键名
                $k = $this->formatRequestString($k, $strSeqList);
                if ($isBody) {
                    $s = $k . $s;                    
                } else {
                    $s = $k . ' ' . $s;
                }
                // 包含<partial>
                if ($supportPartial) {
                    $s .= $partialStr;
                }
            }
            $a[] = $s;
        }
        if ($level < 0) {
            return implode(' ', $a);
        } elseif (($level % 2) == 0) {
            return sprintf('(%s)', implode(' ', $a));
        } else {
            return sprintf('[%s]', implode(' ', $a));
        }
    }
    private function formatSequence($seq) {
        $n = count($seq);
        if ($n == 0) {
            return '1:*';            
        } elseif ($n == 1) {
            if (isset($seq[0])) {
                return strval($seq[0]);
            } else {
                foreach ($seq as $k => $v) {
                    return $k . ':' . $v;
                }
            }
        } else {
            return implode(',', $seq);
        }
    }
    private function formatArgsForCommand(&$data, &$fields, $asList = false) {
        $args = array();
        foreach ($data as $k => $v) {            
            if (is_numeric($k)) {
                // 无值参数
                $name = strtoupper($v);
                if (isset($fields[$name])) {
                    // 对于排他性属性，直接返回
                    if (($fields[$name] & self::PARAM_EXCLUSIVE) > 0) {
                        return $name;
                    } elseif (($fields[$name] & self::PARAM_NO) > 0) {                
                        $args[] = $name;
                    }
                }
            } elseif ($k == self::SEQUENCE_PARAM_NAME) {
                // 序列
                $args[] = $this->formatSequence($v);                
            } else {
                $name = strtoupper($k);
                if (isset($fields[$name])) {
                    $paramType = $fields[$name];                    
                    // 格式化参数类型
                    if (($paramType & self::PARAM_DATE) > 0) {
                        $v = date('j-M-Y', $v);
                    } elseif (($paramType & self::PARAM_SEQUENCE) > 0) {
                        $v = $this->formatSequence($v);
                    }                        

                    // 根据参数定义拼组参数列表
                    if (($paramType & self::PARAM_SINGLE) > 0) {
                        // 单值参数
                        if ($asList) {
                            $args[] = $name;
                            $args[] = $v;
                        } else {
                            $args[$name] = $v;
                        }
                    } elseif (($paramType & self::PARAM_PAIR) > 0) {
                        // 键值对参数
                        if (is_array($v)) {
                            foreach ($v as $x => $y) {
                                $pk = $x;
                                $pv = $y;
                                break;
                            }
                        } else {
                            $pk = $v;
                            $pv = '';
                        }
                        if ($asList) {
                            $args[] = $name;
                            $args[] = $pk;
                            $args[] = $pv;
                        } else {
                            $args[$name] = array($pk => $pv);
                        }
                    } elseif (($paramType & self::PARAM_LIST) > 0) {
                        // 列表参数
                        if ($asList) {
                            $args[] = $name;
                            foreach ($v as $i) {
                                $args[] = $i;
                            }
                        } else {
                            $args[$name] = $v;
                        }
                    } elseif (($paramType & self::PARAM_NO) > 0) {
                        // 无值参数
                        $args[] = $name;
                    }
                }
            }
        }
        return $args;
    }
    private function getResponse($tag = null) {
        $r = array();
        $readMore = true;  
        while ($readMore) {
            $ln = trim($this->sock->readLine());            
            if (!isset($ln[0])) {
                // connection closed or read empty string, throw exception to avoid dead loop and reconnect
                throw new Exception('read response failed');
            }
            
            $matches = null;
            $strSeqKey = null;
            $strSeq = null;
            if (preg_match(self::PATTERN_RESPONSE_STRING_SEQUENCE, $ln, $matches)) {
                $strSeqKey = $matches[0];
                $this->readSequence($ln, $strSeq, $matches[1]);
            }
            $this->lastRecv = $ln;
            
            // 区分处理不同种响应
            switch ($ln[0]) {
                case '*':
                    $r[] = $this->parseLine($ln, $strSeqKey, $strSeq);                                        
                    if (!$tag) {
                        $readMore = false;
                    }
                    break;
                case $this->tagName:
                    $r[] = $this->parseLine($ln);
                    if ($tag) {
                        $readMore = false;
                    } else {
                        
                    }
                    break;
                case '+':
                    $r[] = $this->parseLine($ln);
                    $readMore = false;
                    break;
                default:
                    $r[] = $ln;
                    break;
            }                        
        }        
        
        //var_dump($this->lastSend, $this->lastRecv);
        
        // 无响应数据
        if (empty($r)) {
            throw new Exception('no response');
        }
                                                
        $last = $r[count($r) - 1];
        if (isset($last[0]) && $last[0] == '+') {
            // 继续发送请求数据
        } else {
            if ($tag) {
                if (!isset($last[0]) || strcasecmp($last[0], $tag) != 0) {                    
                    throw new Exception('tag no match');
                }           
            } else {
                if (!isset($last[0]) || strcasecmp($last[0], '*') != 0) {                    
                    throw new Exception('untag no match');
                }
            }
            if (isset($last[1])) {
                // 处理响应出错的情况
                if (strcasecmp($last[1], 'bad') == 0) {        
                    throw new Exception(implode(' ', $last));
                } elseif (strcasecmp($last[1], 'no') == 0) {
                    throw new Exception(implode(' ', $last));
                }
            }
            //$this->currentCommand = null;
        }
        
        return $r;
    }
    
    private function readSequence(&$ln, &$strSeq, $seqLength) {
        // 对于字符串序列，读取完整内容后再拼接响应        
        $readLen = 0;
        $st = microtime(true);
        // 网络请求多次读取字符串序列内容，直到读好为止
        while ($readLen < $seqLength) {
            $sb = $this->sock->read($seqLength - $readLen);
            if (isset($sb[0])) {
                $strSeq .= $sb;
                $readLen = strlen($strSeq);
            }                    
            if ((microtime(true) - $st) > $this->timeout) {
                throw new Exception('read sequence timeout');
            }
        }
        // 读取字符串序列后的剩余命令
        $leftLn = rtrim($this->sock->readLine());
        $ln = $ln . $leftLn;
    }
    
    private function parseLine($ln, $strSeqKey = null, $strSeq = null) {
        $r = array();
        $p =& $r;
        $stack = array();
        $token = '';
        $escape = false;
        $inQuote = false;
        for ($i = 0, $n = strlen($ln); $i < $n; ++$i) {
            $ch = $ln[$i];
            if ($ch == '"') {
                // 处理双引号括起的字符串
                if (!$inQuote) {
                    $inQuote = true;
                } else {
                    $inQuote = false;
                }
            } elseif ($inQuote) {
                // 对于括起的字符串，处理双引号转义
                if ($ch == '\\') {
                    if (!$escape && isset($ln[$i + 1]) && $ln[$i + 1] == '"') {               
                        $token .= '"';
                        $i++;
                    } else {
                        $token .= $ch;
                        $escape = !$escape;
                    }                    
                } else {
                    $token .= $ch;
                }
            } elseif ($ch == ' ' || 
                $ch == '(' || $ch == ')' || 
                $ch == '[' || $ch == ']') {
                // 处理子列表
                if (isset($token[0])) {
                    // 将字符串序列标识：{length}，替换为真实字符串
                    if ($strSeqKey && $token == $strSeqKey) {
                        $p[] = $strSeq;
                    } else {
                        $p[] = $token;
                    }
                    $token = '';
                }                
                if ($ch == '(' || $ch == '[') {                    
                    $p[] = array();
                    $stack[] =& $p;
                    $p =& $p[count($p) - 1];                                        
                } elseif ($ch == ')' || $ch == ']') {        
                    $p =& $stack[count($stack) - 1];
                    array_pop($stack);
                }
            } else {                
                // 处理字符串字面量
                $token .= $ch;
            }            
        }
        if (isset($token[0])) {
            // 将字符串序列标识：{length}，替换为真实字符串
            if ($strSeqKey && $token == $strSeqKey) {
                $p[] = $strSeq;
            } else {
                $p[] = $token;
            }
        }
        return $r;
    }
}

// end of php

 

socket.php

<?php
class Socket{
    const DEFAULT_READ_SIZE = 8192;
    const CRTL = "\r\n";
    private $uri = null;
    private $timeout = null;
    private $sock = null;
    private $connected = false;
    public function __construct($uri, $timeout = null){
        $this->uri = $uri;
        $this->timeout = $this->formatTimeout($timeout);
    }

    public function connect($timeout = null, $retryTimes = null){
        if ($this->connected) {
            $this->close();
        }

        $connTimeout = $this->formatTimeout($timeout, $this->timeout);
        $retryTimes = intval($retryTimes);
        if ($retryTimes < 1) {
            $retryTimes = 1;
        }
        for ($i = 0; $i < $retryTimes; ++$i) {
            $this->sock = stream_socket_client(
                $this->uri, $errno, $error, $connTimeout);
            if ($this->sock) {
                break;
            }
        }
        if (!$this->sock) {

        }
        stream_set_timeout($this->sock, $this->timeout);
        $this->connected = true;
    }

    public function read($size){
        assert($this->connected);

        $buf = fread($this->sock, $size);
        if ($buf === false) {
            $this->handleReadError();
        }

        return $buf;
    }

    public function readLine(){
        assert($this->connected);
        $buf = '';
        while (true) {
            $s = fgets($this->sock, self::DEFAULT_READ_SIZE);
            if ($s === false) {
                $this->checkReadTimeout();
                break;
            }
            $n = strlen($s);
            if (!$n) {
                break;
            }
            $buf .= $s;
            if ($s[$n - 1] == "\n") {
                break;
            }
        }

        return $buf;
    }

    public function readAll(){
        assert($this->connected);
        $buf = '';
        while (true) {
            $s = fread($this->sock, self::DEFAULT_READ_SIZE);
            if ($s === false) {
                $this->handleReadError();
            }

            if (!isset($s[0])) {
                break;
            }

            $buf .= $s;
        }

        return $buf;
    }

    public function write($s){
        assert($this->connected);
        $n = strlen($s);
        $w = 0;
        while ($w < $n) {
            $buf = substr($s, $w, self::DEFAULT_READ_SIZE);
            $r = fwrite($this->sock, $buf);
            if (!$r) {
                $this->close();
            }
            $w += $r;
        }
    }
    public function writeLine($s){
        $this->write($s . self::CRTL);
    }
    public function close() {
        if ($this->connected) {
            fclose($this->sock);
            $this->connected = false;
        }
    }
    private function formatTimeout($timeout, $default = null){
        $t = intval($timeout);
        if ($t <= 0) {
            if (!$default) {
                $t = ini_get('default_socket_timeout');
            } else {
                $t = $default;
            }
        }
        return $t;
    }

    private function checkReadTimeout(){
        $meta = stream_get_meta_data($this->sock);
        if (isset($meta['timed_out'])) {
            $this->close();
        }
    }

    private function handleReadError(){
        $this->checkReadTimeout();
        $this->close();
    }
}