cleanup context handling for wrappers

src/WrapperHandler.php

@@ -0,0 +1,108 @@
+<?php
+/**
+ * @copyright Copyright (c) 2019 Robin Appelman <robin@icewind.nl>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace Icewind\Streams;
+
+
+class WrapperHandler {
+	const NO_SOURCE_DIR = 1;
+
+	/**
+	 * get the protocol name that is generated for the class
+	 * @param string|null $class
+	 * @return string
+	 */
+	public static function getProtocol($class = null) {
+		if ($class === null) {
+			$class = static::class;
+		}
+
+		$parts = explode('\\', $class);
+		return strtolower(array_pop($parts));
+	}
+
+	/**
+	 * @param resource|int $source
+	 * @param resource|array $context
+	 * @param null $protocol deprecated, protocol is now automatically generated
+	 * @param null $class deprecated, class is now automatically generated
+	 * @return bool|resource
+	 */
+	protected static function wrapSource($source, $context = [], $protocol = null, $class = null) {
+		if ($class === null) {
+			$class = static::class;
+		}
+
+		$protocol = self::getProtocol($class);
+
+		if (is_array($context)) {
+			$context['source'] = $source;
+			$context = stream_context_create([$protocol => $context]);
+		}
+
+		if ($source !== self::NO_SOURCE_DIR && !is_resource($source)) {
+			throw new \BadMethodCallException();
+		}
+		try {
+			stream_wrapper_register($protocol, $class);
+			if (self::isDirectoryHandle($source)) {
+				$wrapped = opendir($protocol . '://', $context);
+			} else {
+				$wrapped = fopen($protocol . '://', 'r+', false, $context);
+			}
+		} catch (\BadMethodCallException $e) {
+			stream_wrapper_unregister($protocol);
+			throw $e;
+		}
+		stream_wrapper_unregister($protocol);
+		return $wrapped;
+	}
+
+	protected static function isDirectoryHandle($resource) {
+		if ($resource === self::NO_SOURCE_DIR) {
+			return true;
+		}
+		$meta = stream_get_meta_data($resource);
+		return $meta['stream_type'] === 'dir' || $meta['stream_type'] === 'user-space-dir';
+	}
+
+	/**
+	 * Load the source from the stream context and return the context options
+	 *
+	 * @param string|null $name if not set, the generated protocol name is used
+	 * @return array
+	 * @throws \BadMethodCallException
+	 */
+	protected function loadContext($name = null) {
+		if ($name === null) {
+			$parts = explode('\\', static::class);
+			$name = strtolower(array_pop($parts));
+		}
+
+		$context = stream_context_get_options($this->context);
+		if (isset($context[$name])) {
+			$context = $context[$name];
+		} else {
+			throw new \BadMethodCallException('Invalid context, "' . $name . '" options not set');
+		}
+		return $context;
+	}
+}