Subversion-Projekte lars-tiefland.php_share

<?php

/*

 *  $Id: FileReader.php 123 2006-09-14 20:19:08Z mrook $

 *

 * 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>.

 */

/**

 * Wrapper class for PHP stream that supports read operations.

 *

 * @package   phing.system.io

 */

class InputStream {

	/**

	 * @var resource The attached PHP stream.

	 */

	protected $stream;

	/**

	 * @var int Position of stream cursor.

	 */

    protected $currentPosition = 0;

    /**

     * @var int Marked position of stream cursor.

     */

    protected $mark = 0;

	/**

     * Construct a new InputStream.

     * @param resource $stream Configured PHP stream for writing.

     */

    public function __construct($stream) {

    	if (!is_resource($stream)) {

    		throw new IOException("Passed argument is not a valid stream.");

    	}

    	$this->stream = $stream;

    }

    /**

     * Skip over $n bytes.

     * @param int $n

     */

    public function skip($n) {

        $start = $this->currentPosition;

        $ret = @fseek($this->stream, $n, SEEK_CUR);

        if ( $ret === -1 )

            return -1;

        $this->currentPosition = ftell($this->stream);

        if ( $start > $this->currentPosition )

            $skipped = $start - $this->currentPosition;

        else

            $skipped = $this->currentPosition - $start;

        return $skipped;

    }

    /**

     * Read data from stream until $len chars or EOF.

     * @param int $len Num chars to read.  If not specified this stream will read until EOF.

     * @return string chars read or -1 if eof.

     */

    public function read($len = null) {

        if ($this->eof()) {

            return -1;

        }

        if ($len === null) { // we want to keep reading until we get an eof

			$out = "";

        	while(!$this->eof()) {

        		$out .= fread($this->stream, 8192);

        		$this->currentPosition = ftell($this->stream);

        	}

        } else {

			$out = fread($this->stream, $len); // adding 1 seems to ensure that next call to read() will return EOF (-1)

        	$this->currentPosition = ftell($this->stream);

        }

        return $out;

    }

    /**

     * Marks the current position in this input stream.

     * @throws IOException - if the underlying stream doesn't support this method.

     */

    public function mark() {

    	if (!$this->markSupported()) {

    		throw new IOException(get_class($this) . " does not support mark() and reset() methods.");

    	}

        $this->mark = $this->currentPosition;

    }

    /**

     * Whether the input stream supports mark and reset methods.

     * @return boolean

     */

    public function markSupported() {

    	return false;

    }

    /**

     * Repositions this stream to the position at the time the mark method was last called on this input stream.

     * @throws IOException - if the underlying stream doesn't support this method.

     */

    function reset() {

    	if (!$this->markSupported()) {

    		throw new IOException(get_class($this) . " does not support mark() and reset() methods.");

    	}

        // goes back to last mark, by default this would be 0 (i.e. rewind file).

        fseek($this->stream, SEEK_SET, $this->mark);

        $this->mark = 0;

    }

    /**

     * Closes stream.

     * @throws IOException if stream cannot be closed (note that calling close() on an already-closed stream will not raise an exception)

     */

    public function close() {

        if ($this->stream === null) {

            return;

        }

        if (false === @fclose($this->stream)) {

            // FAILED.

            $msg = "Cannot fclose " . $this->file->__toString() . " $php_errormsg";

            throw new IOException($msg);

        }

        $this->stream = null;

    }

    /**

     * Whether eof has been reached with stream.

     * @return boolean

     */

    public function eof() {

        return feof($this->stream);

    }

    /**

     * Reads a entire until EOF and places contents in passed-in variable.  Stream is closed after read.

     *

     * @param string &$rBuffer String variable where read contents will be put.

     * @return TRUE on success.

     * @author  Charlie Killian, charlie@tizac.com

     * @throws IOException - if there is an error reading from stream.

     * @deprecated - Instead, use the read() method or a BufferedReader.

     */

    public function readInto(&$rBuffer) {

		$rBuffer = $this->read();

		$this->close();

    }

    /**

     * Returns string representation of attached stream.

     * @return string

     */

    public function __toString() {

        return (string) $this->stream;

    }

}