1: <?php
  2: 
  3: /**
  4:  * Copyright (c) 2006- Facebook
  5:  * Distributed under the Thrift Software License
  6:  *
  7:  * See accompanying file LICENSE or visit the Thrift site at:
  8:  * http://developers.facebook.com/thrift/
  9:  *
 10:  * @package thrift.transport
 11:  * @author Mark Slee <mcslee@facebook.com>
 12:  */
 13: 
 14: /**
 15:  * Buffered transport. Stores data to an internal buffer that it doesn't
 16:  * actually write out until flush is called. For reading, we do a greedy
 17:  * read and then serve data out of the internal buffer.
 18:  *
 19:  * @package thrift.transport
 20:  * @author Mark Slee <mcslee@facebook.com>
 21:  */
 22: class TBufferedTransport extends TTransport {
 23: 
 24:   /**
 25:    * Constructor. Creates a buffered transport around an underlying transport
 26:    */
 27:   public function __construct($transport=null, $rBufSize=512, $wBufSize=512) {
 28:     $this->transport_ = $transport;
 29:     $this->rBufSize_ = $rBufSize;
 30:     $this->wBufSize_ = $wBufSize;
 31:   }
 32: 
 33:   /**
 34:    * The underlying transport
 35:    *
 36:    * @var TTransport
 37:    */
 38:   protected $transport_ = null;
 39: 
 40:   /**
 41:    * The receive buffer size
 42:    *
 43:    * @var int
 44:    */
 45:   protected $rBufSize_ = 512;
 46: 
 47:   /**
 48:    * The write buffer size
 49:    *
 50:    * @var int
 51:    */
 52:   protected $wBufSize_ = 512;
 53: 
 54:   /**
 55:    * The write buffer.
 56:    *
 57:    * @var string
 58:    */
 59:   protected $wBuf_ = '';
 60: 
 61:   /**
 62:    * The read buffer.
 63:    *
 64:    * @var string
 65:    */
 66:   protected $rBuf_ = '';
 67: 
 68:   public function isOpen() {
 69:     return $this->transport_->isOpen();
 70:   }
 71: 
 72:   public function open() {
 73:     $this->transport_->open();
 74:   }
 75: 
 76:   public function close() {
 77:     $this->transport_->close();
 78:   }
 79: 
 80:   public function putBack($data) {
 81:     if (strlen($this->rBuf_) === 0) {
 82:       $this->rBuf_ = $data;
 83:     } else {
 84:       $this->rBuf_ = ($data . $this->rBuf_);
 85:     }
 86:   }
 87: 
 88:   /**
 89:    * The reason that we customize readAll here is that the majority of PHP
 90:    * streams are already internally buffered by PHP. The socket stream, for
 91:    * example, buffers internally and blocks if you call read with $len greater
 92:    * than the amount of data available, unlike recv() in C.
 93:    *
 94:    * Therefore, use the readAll method of the wrapped transport inside
 95:    * the buffered readAll.
 96:    */
 97:   public function readAll($len) {
 98:     $have = strlen($this->rBuf_);
 99:     if ($have == 0) {
100:       $data = $this->transport_->readAll($len);
101:     } else if ($have < $len) {
102:       $data = $this->rBuf_;
103:       $this->rBuf_ = '';
104:       $data .= $this->transport_->readAll($len - $have);
105:     } else if ($have == $len) {
106:       $data = $this->rBuf_;
107:       $this->rBuf_ = '';
108:     } else if ($have > $len) {
109:       $data = substr($this->rBuf_, 0, $len);
110:       $this->rBuf_ = substr($this->rBuf_, $len);
111:     }
112:     return $data;
113:   }
114: 
115:   public function read($len) {
116:     if (strlen($this->rBuf_) === 0) {
117:       $this->rBuf_ = $this->transport_->read($this->rBufSize_);
118:     }
119: 
120:     if (strlen($this->rBuf_) <= $len) {
121:       $ret = $this->rBuf_;
122:       $this->rBuf_ = '';
123:       return $ret;
124:     }
125: 
126:     $ret = substr($this->rBuf_, 0, $len);
127:     $this->rBuf_ = substr($this->rBuf_, $len);
128:     return $ret;
129:   }
130: 
131:   public function write($buf) {
132:     $this->wBuf_ .= $buf;
133:     if (strlen($this->wBuf_) >= $this->wBufSize_) {
134:       $out = $this->wBuf_;
135: 
136:       // Note that we clear the internal wBuf_ prior to the underlying write
137:       // to ensure we're in a sane state (i.e. internal buffer cleaned)
138:       // if the underlying write throws up an exception
139:       $this->wBuf_ = '';
140:       $this->transport_->write($out);
141:     }
142:   }
143: 
144:   public function flush() {
145:     if (strlen($this->wBuf_) > 0) {
146:       $this->transport_->write($this->wBuf_);
147:       $this->wBuf_ = '';
148:     }
149:     $this->transport_->flush();
150:   }
151: 
152: }
153: 
154: ?>
155: