text: <?php
  /*
   *  $Id: BufferedReader.php 3076 2006-12-18 08:52:12Z fabien $
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   *
   * This software consists of voluntary contributions made by many individuals
   * and is licensed under the LGPL. For more information please see
   * <http://phing.info>.
  */
  
  include_once 'phing/system/io/Reader.php';
  
  /*
   * Convenience class for reading files.
   *
   * @author    <a href="mailto:yl@seasonfive.com">Yannick Lecaillez</a>
   * @version   $Revision: 1.6 $ $Date: 2005/12/27 19:12:13 $
   * @access    public
   * @see       FilterReader
   * @package   phing.system.io
  */
  class BufferedReader extends Reader {
  
      private $bufferSize = 0;
      private $buffer     = null;
      private $bufferPos  = 0;
      
      /**
       * The Reader we are buffering for.
       */
      private $in;
      
      /**
       * 
       * @param object $reader The reader (e.g. FileReader).
       * @param integer $buffsize The size of the buffer we should use for reading files.
       *                             A large buffer ensures that most files (all scripts?) are parsed in 1 buffer.
       */     
      function __construct(Reader $reader, $buffsize = 65536) {
          $this->in = $reader;
          $this->bufferSize = $buffsize;
      }
  
      /**
       * Reads and returns $_bufferSize chunk of data.
       * @return mixed buffer or -1 if EOF.
       */
      function read($len = null) {
          // ignore $len param, not sure how to hanlde it, since 
          // this should only read bufferSize amount of data.
          if ($len !== null) {
              $this->currentPosition = ftell($this->fd);
          }
          
          if ( ($data = $this->in->read($this->bufferSize)) !== -1 ) {
  		
  			// not all files end with a newline character, so we also need to check EOF
  			if (!$this->in->eof()) {
  			
  	            $notValidPart = strrchr($data, "\n");
  	            $notValidPartSize = strlen($notValidPart);
  	        
  	            if ( $notValidPartSize > 1 ) {
  	                // Block doesn't finish on a EOL
  	                // Find the last EOL and forgot all following stuff
  	                $dataSize = strlen($data);
  	                $validSize = $dataSize - $notValidPartSize + 1;
  	            
  	                $data = substr($data, 0, $validSize);
  	
  	                // Rewind to the begining of the forgotten stuff.
  	                $this->in->skip(-$notValidPartSize+1);
  	            }
  				
  			} // if !EOF
          }
          return $data;
      }
      
      function skip($n) {
          return $this->in->skip($n);
      }
      
      function reset() {
          return $this->in->reset();
      }
      
      function close() {
          return $this->in->close();
      }
      
      function open() {
          return $this->in->open();
      }
      
      /**
       * Read a line from input stream.
       */
      function readLine() {
          $line = null;
          while ( ($ch = $this->readChar()) !== -1 ) {
              if ( $ch === "\n" ) {
                  break;
              }
              $line .= $ch;
          }
  
          // Warning : Not considering an empty line as an EOF
          if ( $line === null && $ch !== -1 )
              return "";
  
          return $line;
      }
      
      /**
       * Reads a single char from the reader.
       * @return string single char or -1 if EOF.
       */
      function readChar() {        
  
          if ( $this->buffer === null ) {
              // Buffer is empty, fill it ...
              $read = $this->in->read($this->bufferSize);
              if ($read === -1) {
                  $ch = -1;
              } else {
                  $this->buffer = $read;
                  return $this->readChar(); // recurse
              }
          } else {            
              // Get next buffered char ...
              // handle case where buffer is read-in, but is empty.  The next readChar() will return -1 EOF,
              // so we just return empty string (char) at this point.  (Probably could also return -1 ...?)
              $ch = ($this->buffer !== "") ? $this->buffer{$this->bufferPos} : '';
              $this->bufferPos++;
              if ( $this->bufferPos >= strlen($this->buffer) ) {
                  $this->buffer = null;
                  $this->bufferPos = 0;
              }
          }
  
          return $ch;
      }
      
      /**
       * Returns whether eof has been reached in stream.
       * This is important, because filters may want to know if the end of the file (and not just buffer)
       * has been reached.
       * @return boolean
       */ 
      function eof() {
          return $this->in->eof();
      }
  
      function getResource() {
          return $this->in->getResource();
      }    
  }
  ?>
  