Add a ISeekableStream interface

Author: na2axl

src/Core/Streams/ISeekableStream.php

@@ -0,0 +1,85 @@
+<?php
+
+/**
+ * Streams
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * @category  Library
+ * @package   Streams
+ * @author    Axel Nana <ax.lnana@outlook.com>
+ * @copyright 2019 Aliens Group.
+ * @license   MIT <https://github.com/ElementaryFramework/Streams/blob/master/LICENSE>
+ * @version   GIT: 0.0.1
+ */
+
+namespace ElementaryFramework\Core\Streams;
+
+/**
+ * Seekable Stream Interface
+ *
+ * Interface with base methods to implement a
+ * stream with seekable cursor capabilities.
+ *
+ * @package    Streams
+ * @author     Axel Nana <ax.lnana@outlook.com>
+ */
+interface ISeekableStream extends IStream
+{
+    /**
+     * Seeks the stream cursor to the given position.
+     *
+     * @param int $offset The offset to move the cursor.
+     *
+     * The stream cursor's final position will depend of `$whence`.
+     * - If `$whence` is equal to `SEEK_SET`, `$offset` will represent
+     * the amount of bytes from the start of the stream.
+     * - If `$whence` is equal to `SEEK_CUR`, the final cursor position
+     * will be the current position plus `$offset`.
+     * - If `$whence` is equal to `SEEK_END`, the final cursor position
+     * will be the last possible position in the stream plus `$offset`.
+     *
+     * To move backward from the end of the stream, set `$offset` to an
+     * negative number and `$whence` to `SEEK_END`.
+     *
+     * @param int $whence The origin of `$offset`.
+     *
+     * Possible values are:
+     * - `SEEK_SET` to start from the beginning.
+     * - `SEEK_CUR` to start from the current position.
+     * - `SEEK_END` to start from the last position.
+     *
+     * @return void
+     */
+    function seekTo(int $offset, int $whence = SEEK_SET) : void;
+
+    /**
+     * Seeks the stream cursor to the beginning.
+     *
+     * @return void
+     */
+    function seekToStart() : void;
+
+    /**
+     * Seeks the stream cursor to the end.
+     *
+     * @return void
+     */
+    function seekToEnd() : void;
+}