upgrade to sabre32

23 files changed, 1204 insertions, 88 deletions

diff --git a/vendor/sabre/dav/lib/DAV/Auth/Backend/AbstractDigest.php b/vendor/sabre/dav/lib/DAV/Auth/Backend/AbstractDigest.php
index 0251decc1..85c5f30d5 100644
--- a/vendor/sabre/dav/lib/DAV/Auth/Backend/AbstractDigest.php
+++ b/vendor/sabre/dav/lib/DAV/Auth/Backend/AbstractDigest.php
@@ -155,8 +155,14 @@ abstract class AbstractDigest implements BackendInterface {
             $response
         );
         $auth->init();
+
+        $oldStatus = $response->getStatus() ?: 200;
         $auth->requireLogin();
 
+        // Preventing the digest utility from modifying the http status code,
+        // this should be handled by the main plugin.
+        $response->setStatus($oldStatus);
+
     }
 
 }
diff --git a/vendor/sabre/dav/lib/DAV/Auth/Plugin.php b/vendor/sabre/dav/lib/DAV/Auth/Plugin.php
index 818d8a4ad..4b5f35ac3 100644
--- a/vendor/sabre/dav/lib/DAV/Auth/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Auth/Plugin.php
@@ -4,7 +4,6 @@ namespace Sabre\DAV\Auth;
 
 use Sabre\HTTP\RequestInterface;
 use Sabre\HTTP\ResponseInterface;
-use Sabre\HTTP\URLUtil;
 use Sabre\DAV\Exception\NotAuthenticated;
 use Sabre\DAV\Server;
 use Sabre\DAV\ServerPlugin;
@@ -26,6 +25,20 @@ use Sabre\DAV\ServerPlugin;
 class Plugin extends ServerPlugin {
 
     /**
+     * By default this plugin will require that the user is authenticated,
+     * and refuse any access if the user is not authenticated.
+     *
+     * If this setting is set to false, we let the user through, whether they
+     * are authenticated or not.
+     *
+     * This is useful if you want to allow both authenticated and
+     * unauthenticated access to your server.
+     *
+     * @param bool
+     */
+    public $autoRequireLogin = true;
+
+    /**
      * authentication backends
      */
     protected $backends;
@@ -108,27 +121,6 @@ class Plugin extends ServerPlugin {
     }
 
     /**
-     * Returns the current username.
-     *
-     * This method is deprecated and is only kept for backwards compatibility
-     * purposes. Please switch to getCurrentPrincipal().
-     *
-     * @deprecated Will be removed in a future version!
-     * @return string|null
-     */
-    function getCurrentUser() {
-
-        // We just do a 'basename' on the principal to give back a sane value
-        // here.
-        list(, $userName) = URLUtil::splitPath(
-            $this->getCurrentPrincipal()
-        );
-
-        return $userName;
-
-    }
-
-    /**
      * This method is called before any HTTP method and forces users to be authenticated
      *
      * @param RequestInterface $request
@@ -154,6 +146,50 @@ class Plugin extends ServerPlugin {
             return;
 
         }
+
+        $authResult = $this->check($request, $response);
+
+        if ($authResult[0]) {
+            // Auth was successful
+            $this->currentPrincipal = $authResult[1];
+            $this->loginFailedReasons = null;
+            return;
+        }
+
+
+
+        // If we got here, it means that no authentication backend was
+        // successful in authenticating the user.
+        $this->currentPrincipal = null;
+        $this->loginFailedReasons = $authResult[1];
+
+        if ($this->autoRequireLogin) {
+            $this->challenge($request, $response);
+            throw new NotAuthenticated(implode(', ', $authResult[1]));
+        }
+
+    }
+
+    /**
+     * Checks authentication credentials, and logs the user in if possible.
+     *
+     * This method returns an array. The first item in the array is a boolean
+     * indicating if login was successful.
+     *
+     * If login was successful, the second item in the array will contain the
+     * current principal url/path of the logged in user.
+     *
+     * If login was not successful, the second item in the array will contain a
+     * an array with strings. The strings are a list of reasons why login was
+     * unsuccesful. For every auth backend there will be one reason, so usually
+     * there's just one.
+     *
+     * @param RequestInterface $request
+     * @param ResponseInterface $response
+     * @return array
+     */
+    function check(RequestInterface $request, ResponseInterface $response) {
+
         if (!$this->backends) {
             throw new \Sabre\DAV\Exception('No authentication backends were configured on this server.');
         }
@@ -172,20 +208,56 @@ class Plugin extends ServerPlugin {
             if ($result[0]) {
                 $this->currentPrincipal = $result[1];
                 // Exit early
-                return;
+                return [true, $result[1]];
             }
             $reasons[] = $result[1];
 
         }
 
-        // If we got here, it means that no authentication backend was
-        // successful in authenticating the user.
-        $this->currentPrincipal = null;
+        return [false, $reasons];
+
+    }
+
+    /**
+     * This method sends authentication challenges to the user.
+     *
+     * This method will for example cause a HTTP Basic backend to set a
+     * WWW-Authorization header, indicating to the client that it should
+     * authenticate.
+     *
+     * @param RequestInterface $request
+     * @param ResponseInterface $response
+     * @return array
+     */
+    function challenge(RequestInterface $request, ResponseInterface $response) {
 
         foreach ($this->backends as $backend) {
             $backend->challenge($request, $response);
         }
-        throw new NotAuthenticated(implode(', ', $reasons));
+
+    }
+
+    /**
+     * List of reasons why login failed for the last login operation.
+     *
+     * @var string[]|null
+     */
+    protected $loginFailedReasons;
+
+    /**
+     * Returns a list of reasons why login was unsuccessful.
+     *
+     * This method will return the login failed reasons for the last login
+     * operation. One for each auth backend.
+     *
+     * This method returns null if the last authentication attempt was
+     * successful, or if there was no authentication attempt yet.
+     *
+     * @return string[]|null
+     */
+    function getLoginFailedReasons() {
+
+        return $this->loginFailedReasons;
 
     }
 
diff --git a/vendor/sabre/dav/lib/DAV/Browser/Plugin.php b/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
index 07ca6c3e5..49359a045 100644
--- a/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
+++ b/vendor/sabre/dav/lib/DAV/Browser/Plugin.php
@@ -48,7 +48,7 @@ class Plugin extends DAV\ServerPlugin {
     public $uninterestingProperties = [
         '{DAV:}supportedlock',
         '{DAV:}acl-restrictions',
-        '{DAV:}supported-privilege-set',
+//        '{DAV:}supported-privilege-set',
         '{DAV:}supported-method-set',
     ];
 
@@ -112,7 +112,7 @@ class Plugin extends DAV\ServerPlugin {
         $getVars = $request->getQueryParameters();
 
         // CSP headers
-        $this->server->httpResponse->setHeader('Content-Security-Policy', "img-src 'self'; style-src 'self';");
+        $this->server->httpResponse->setHeader('Content-Security-Policy', "default-src 'none'; img-src 'self'; style-src 'self'; font-src 'self';");
 
         $sabreAction = isset($getVars['sabreAction']) ? $getVars['sabreAction'] : null;
 
@@ -354,7 +354,7 @@ class Plugin extends DAV\ServerPlugin {
 
         $output = '';
         if ($this->enablePost) {
-            $this->server->emit('onHTMLActionsPanel', [$node, &$output]);
+            $this->server->emit('onHTMLActionsPanel', [$node, &$output, $path]);
         }
 
         if ($output) {
@@ -368,7 +368,7 @@ class Plugin extends DAV\ServerPlugin {
 
         $html .= $this->generateFooter();
 
-        $this->server->httpResponse->setHeader('Content-Security-Policy', "img-src 'self'; style-src 'self';");
+        $this->server->httpResponse->setHeader('Content-Security-Policy', "default-src 'none'; img-src 'self'; style-src 'self'; font-src 'self';");
 
         return $html;
 
@@ -477,7 +477,7 @@ HTML;
 
         $version = DAV\Version::VERSION;
         return <<<HTML
-<footer>Generated by SabreDAV $version (c)2007-2015 <a href="http://sabre.io/">http://sabre.io/</a></footer>
+<footer>Generated by SabreDAV $version (c)2007-2016 <a href="http://sabre.io/">http://sabre.io/</a></footer>
 </body>
 </html>
 HTML;
@@ -493,9 +493,10 @@ HTML;
      *
      * @param DAV\INode $node
      * @param mixed $output
+     * @param string $path
      * @return void
      */
-    function htmlActionsPanel(DAV\INode $node, &$output) {
+    function htmlActionsPanel(DAV\INode $node, &$output, $path) {
 
         if (!$node instanceof DAV\ICollection)
             return;
diff --git a/vendor/sabre/dav/lib/DAV/Browser/assets/sabredav.css b/vendor/sabre/dav/lib/DAV/Browser/assets/sabredav.css
index c9ab2c74f..8869597f0 100644
--- a/vendor/sabre/dav/lib/DAV/Browser/assets/sabredav.css
+++ b/vendor/sabre/dav/lib/DAV/Browser/assets/sabredav.css
@@ -96,12 +96,12 @@ header a {
   vertical-align: middle;
   border: 0;
 }
-input, button {
+input, button, select {
     font: inherit;
     color: inherit;
 }
 
-input[type=text] {
+input[type=text], select {
   border: 1px solid #bbbbbb;
   line-height: 22px;
   padding: 5px 10px;
@@ -200,7 +200,7 @@ section table {
     line-height: 40px;
 }
 
-.actions input[type=text] {
+.actions input[type=text], select {
     width: 450px;
 }
 
diff --git a/vendor/sabre/dav/lib/DAV/Client.php b/vendor/sabre/dav/lib/DAV/Client.php
index d46b397b6..08d5d4702 100644
--- a/vendor/sabre/dav/lib/DAV/Client.php
+++ b/vendor/sabre/dav/lib/DAV/Client.php
@@ -3,6 +3,7 @@
 namespace Sabre\DAV;
 
 use Sabre\HTTP;
+use Sabre\Uri;
 
 /**
  * SabreDAV DAV client
@@ -387,20 +388,10 @@ class Client extends HTTP\Client {
      */
     function getAbsoluteUrl($url) {
 
-        // If the url starts with http:// or https://, the url is already absolute.
-        if (preg_match('/^http(s?):\/\//', $url)) {
-            return $url;
-        }
-
-        // If the url starts with a slash, we must calculate the url based off
-        // the root of the base url.
-        if (strpos($url, '/') === 0) {
-            $parts = parse_url($this->baseUri);
-            return $parts['scheme'] . '://' . $parts['host'] . (isset($parts['port']) ? ':' . $parts['port'] : '') . $url;
-        }
-
-        // Otherwise...
-        return $this->baseUri . $url;
+        return Uri\resolve(
+            $this->baseUri,
+            $url
+        );
 
     }
 
diff --git a/vendor/sabre/dav/lib/DAV/CorePlugin.php b/vendor/sabre/dav/lib/DAV/CorePlugin.php
index 3a70b2a7e..a1b052915 100644
--- a/vendor/sabre/dav/lib/DAV/CorePlugin.php
+++ b/vendor/sabre/dav/lib/DAV/CorePlugin.php
@@ -50,6 +50,8 @@ class CorePlugin extends ServerPlugin {
         $server->on('propFind',         [$this, 'propFindNode'], 120);
         $server->on('propFind',         [$this, 'propFindLate'], 200);
 
+        $server->on('exception',        [$this, 'exception']);
+
     }
 
     /**
@@ -844,10 +846,8 @@ class CorePlugin extends ServerPlugin {
         if ($node instanceof IProperties && $propertyNames = $propFind->get404Properties()) {
 
             $nodeProperties = $node->getProperties($propertyNames);
-            foreach ($propertyNames as $propertyName) {
-                if (array_key_exists($propertyName, $nodeProperties)) {
-                    $propFind->set($propertyName, $nodeProperties[$propertyName], 200);
-                }
+            foreach ($nodeProperties as $propertyName => $propertyValue) {
+                $propFind->set($propertyName, $propertyValue, 200);
             }
 
         }
@@ -905,6 +905,38 @@ class CorePlugin extends ServerPlugin {
     }
 
     /**
+     * Listens for exception events, and automatically logs them.
+     *
+     * @param Exception $e
+     */
+    function exception($e) {
+
+        $logLevel = \Psr\Log\LogLevel::CRITICAL;
+        if ($e instanceof \Sabre\DAV\Exception) {
+            // If it's a standard sabre/dav exception, it means we have a http
+            // status code available.
+            $code = $e->getHTTPCode();
+
+            if ($code >= 400 && $code < 500) {
+                // user error
+                $logLevel = \Psr\Log\LogLevel::INFO;
+            } else {
+                // Server-side error. We mark it's as an error, but it's not
+                // critical.
+                $logLevel = \Psr\Log\LogLevel::ERROR;
+            }
+        }
+
+        $this->server->getLogger()->log(
+            $logLevel,
+            'Uncaught exception',
+            [
+                'exception' => $e,
+            ]
+        );
+    }
+
+    /**
      * Returns a bunch of meta-data about the plugin.
      *
      * Providing this information is optional, and is mainly displayed by the
diff --git a/vendor/sabre/dav/lib/DAV/FS/Directory.php b/vendor/sabre/dav/lib/DAV/FS/Directory.php
index 963e5554c..362f7a411 100644
--- a/vendor/sabre/dav/lib/DAV/FS/Directory.php
+++ b/vendor/sabre/dav/lib/DAV/FS/Directory.php
@@ -140,10 +140,10 @@ class Directory extends Node implements DAV\ICollection, DAV\IQuota {
      * @return array
      */
     function getQuotaInfo() {
-
+        $absolute = realpath($this->path);
         return [
-            disk_total_space($this->path) - disk_free_space($this->path),
-            disk_free_space($this->path)
+            disk_total_space($absolute) - disk_free_space($absolute),
+            disk_free_space($absolute)
         ];
 
     }
diff --git a/vendor/sabre/dav/lib/DAV/File.php b/vendor/sabre/dav/lib/DAV/File.php
index e0a0391db..675956b22 100644
--- a/vendor/sabre/dav/lib/DAV/File.php
+++ b/vendor/sabre/dav/lib/DAV/File.php
@@ -15,12 +15,24 @@ namespace Sabre\DAV;
 abstract class File extends Node implements IFile {
 
     /**
-     * Updates the data
+     * Replaces the contents of the file.
      *
-     * data is a readable stream resource.
+     * The data argument is a readable stream resource.
      *
-     * @param resource $data
-     * @return void
+     * After a succesful put operation, you may choose to return an ETag. The
+     * etag must always be surrounded by double-quotes. These quotes must
+     * appear in the actual string you're returning.
+     *
+     * Clients may use the ETag from a PUT request to later on make sure that
+     * when they update the file, the contents haven't changed in the mean
+     * time.
+     *
+     * If you don't plan to store the file byte-by-byte, and you return a
+     * different object on a subsequent GET you are strongly recommended to not
+     * return an ETag, and just return null.
+     *
+     * @param string|resource $data
+     * @return string|null
      */
     function put($data) {
 
diff --git a/vendor/sabre/dav/lib/DAV/ICollection.php b/vendor/sabre/dav/lib/DAV/ICollection.php
index 390d9b741..7793070d3 100644
--- a/vendor/sabre/dav/lib/DAV/ICollection.php
+++ b/vendor/sabre/dav/lib/DAV/ICollection.php
@@ -54,14 +54,14 @@ interface ICollection extends INode {
      * exist.
      *
      * @param string $name
-     * @return DAV\INode
+     * @return INode
      */
     function getChild($name);
 
     /**
      * Returns an array with all the child nodes
      *
-     * @return DAV\INode[]
+     * @return INode[]
      */
     function getChildren();
 
diff --git a/vendor/sabre/dav/lib/DAV/IFile.php b/vendor/sabre/dav/lib/DAV/IFile.php
index e16a3a58a..37e7cd33c 100644
--- a/vendor/sabre/dav/lib/DAV/IFile.php
+++ b/vendor/sabre/dav/lib/DAV/IFile.php
@@ -32,7 +32,7 @@ interface IFile extends INode {
      * different object on a subsequent GET you are strongly recommended to not
      * return an ETag, and just return null.
      *
-     * @param resource $data
+     * @param resource|data $data
      * @return string|null
      */
     function put($data);
diff --git a/vendor/sabre/dav/lib/DAV/INode.php b/vendor/sabre/dav/lib/DAV/INode.php
index b5e6cb9ef..bb884934d 100644
--- a/vendor/sabre/dav/lib/DAV/INode.php
+++ b/vendor/sabre/dav/lib/DAV/INode.php
@@ -36,9 +36,10 @@ interface INode {
     function setName($name);
 
     /**
-     * Returns the last modification time, as a unix timestamp
+     * Returns the last modification time, as a unix timestamp. Return null
+     * if the information is not available.
      *
-     * @return int
+     * @return int|null
      */
     function getLastModified();
 
diff --git a/vendor/sabre/dav/lib/DAV/PropertyStorage/Backend/PDO.php b/vendor/sabre/dav/lib/DAV/PropertyStorage/Backend/PDO.php
index 910e4979d..2fe843884 100644
--- a/vendor/sabre/dav/lib/DAV/PropertyStorage/Backend/PDO.php
+++ b/vendor/sabre/dav/lib/DAV/PropertyStorage/Backend/PDO.php
@@ -88,6 +88,9 @@ class PDO implements BackendInterface {
         $stmt->execute([$path]);
 
         while ($row = $stmt->fetch(\PDO::FETCH_ASSOC)) {
+            if (gettype($row['value']) === 'resource') {
+                $row['value'] = stream_get_contents($row['value']);
+            }
             switch ($row['valuetype']) {
                 case null :
                 case self::VT_STRING :
@@ -121,7 +124,26 @@ class PDO implements BackendInterface {
 
         $propPatch->handleRemaining(function($properties) use ($path) {
 
-            $updateStmt = $this->pdo->prepare("REPLACE INTO " . $this->tableName . " (path, name, valuetype, value) VALUES (?, ?, ?, ?)");
+
+            if ($this->pdo->getAttribute(\PDO::ATTR_DRIVER_NAME) === 'pgsql') {
+
+                $updateSql = <<<SQL
+INSERT INTO {$this->tableName} (path, name, valuetype, value)
+VALUES (:path, :name, :valuetype, :value)
+ON CONFLICT (path, name)
+DO UPDATE SET valuetype = :valuetype, value = :value
+SQL;
+
+
+            } else {
+                $updateSql = <<<SQL
+REPLACE INTO {$this->tableName} (path, name, valuetype, value)
+VALUES (:path, :name, :valuetype, :value)
+SQL;
+
+            }
+
+            $updateStmt = $this->pdo->prepare($updateSql);
             $deleteStmt = $this->pdo->prepare("DELETE FROM " . $this->tableName . " WHERE path = ? AND name = ?");
 
             foreach ($properties as $name => $value) {
@@ -136,7 +158,14 @@ class PDO implements BackendInterface {
                         $valueType = self::VT_OBJECT;
                         $value = serialize($value);
                     }
-                    $updateStmt->execute([$path, $name, $valueType, $value]);
+
+                    $updateStmt->bindParam('path', $path, \PDO::PARAM_STR);
+                    $updateStmt->bindParam('name', $name, \PDO::PARAM_STR);
+                    $updateStmt->bindParam('valuetype', $valueType, \PDO::PARAM_INT);
+                    $updateStmt->bindParam('value', $value, \PDO::PARAM_LOB);
+
+                    $updateStmt->execute();
+
                 } else {
                     $deleteStmt->execute([$path, $name]);
                 }
diff --git a/vendor/sabre/dav/lib/DAV/Server.php b/vendor/sabre/dav/lib/DAV/Server.php
index b37652812..024b7a557 100644
--- a/vendor/sabre/dav/lib/DAV/Server.php
+++ b/vendor/sabre/dav/lib/DAV/Server.php
@@ -8,6 +8,10 @@ use Sabre\HTTP\RequestInterface;
 use Sabre\HTTP\ResponseInterface;
 use Sabre\HTTP\URLUtil;
 use Sabre\Uri;
+use Psr\Log\LoggerAwareInterface;
+use Psr\Log\LoggerAwareTrait;
+use Psr\Log\LoggerInterface;
+use Psr\Log\NullLogger;
 
 /**
  * Main DAV server class
@@ -16,7 +20,9 @@ use Sabre\Uri;
  * @author Evert Pot (http://evertpot.com/)
  * @license http://sabre.io/license/ Modified BSD License
  */
-class Server extends EventEmitter {
+class Server extends EventEmitter implements LoggerAwareInterface {
+
+    use LoggerAwareTrait;
 
     /**
      * Infinity is used for some request supporting the HTTP Depth header and indicates that the operation should traverse the entire tree
@@ -431,6 +437,20 @@ class Server extends EventEmitter {
     }
 
     /**
+     * Returns the PSR-3 logger objcet.
+     *
+     * @return LoggerInterface
+     */
+    function getLogger() {
+
+        if (!$this->logger) {
+            $this->logger = new NullLogger();
+        }
+        return $this->logger;
+
+    }
+
+    /**
      * Handles a http request, and execute a method based on its name
      *
      * @param RequestInterface $request
@@ -1177,9 +1197,20 @@ class Server extends EventEmitter {
 
         if (!$success) {
             $result = $mkCol->getResult();
-            // generateMkCol needs the href key to exist.
-            $result['href'] = $uri;
-            return $result;
+
+            $formattedResult = [
+                'href' => $uri,
+            ];
+
+            foreach ($result as $propertyName => $status) {
+
+                if (!isset($formattedResult[$status])) {
+                    $formattedResult[$status] = [];
+                }
+                $formattedResult[$status][$propertyName] = null;
+
+            }
+            return $formattedResult;
         }
 
         $this->tree->markDirty($parentUri);
diff --git a/vendor/sabre/dav/lib/DAV/Sharing/ISharedNode.php b/vendor/sabre/dav/lib/DAV/Sharing/ISharedNode.php
new file mode 100644
index 000000000..034aefbdc
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Sharing/ISharedNode.php
@@ -0,0 +1,69 @@
+<?php
+
+namespace Sabre\DAV\Sharing;
+
+use Sabre\DAV\INode;
+
+/**
+ * This interface represents a resource that has sharing capabilities, either
+ * because it's possible for an owner to share the resource, or because this is
+ * an instance of a shared resource.
+ *
+ * @copyright Copyright (C) fruux GmbH. (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+interface ISharedNode extends INode {
+
+    /**
+     * Returns the 'access level' for the instance of this shared resource.
+     *
+     * The value should be one of the Sabre\DAV\Sharing\Plugin::ACCESS_
+     * constants.
+     *
+     * @return int
+     */
+    function getShareAccess();
+
+    /**
+     * This function must return a URI that uniquely identifies the shared
+     * resource. This URI should be identical across instances, and is
+     * also used in several other XML bodies to connect invites to
+     * resources.
+     *
+     * This may simply be a relative reference to the original shared instance,
+     * but it could also be a urn. As long as it's a valid URI and unique.
+     *
+     * @return string
+     */
+    function getShareResourceUri();
+
+    /**
+     * Updates the list of sharees.
+     *
+     * Every item must be a Sharee object.
+     *
+     * @param \Sabre\DAV\Xml\Element\Sharee[] $sharees
+     * @return void
+     */
+    function updateInvites(array $sharees);
+
+    /**
+     * Returns the list of people whom this resource is shared with.
+     *
+     * Every item in the returned array must be a Sharee object with
+     * at least the following properties set:
+     *
+     * * $href
+     * * $shareAccess
+     * * $inviteStatus
+     *
+     * and optionally:
+     *
+     * * $properties
+     *
+     * @return \Sabre\DAV\Xml\Element\Sharee[]
+     */
+    function getInvites();
+
+}
diff --git a/vendor/sabre/dav/lib/DAV/Sharing/Plugin.php b/vendor/sabre/dav/lib/DAV/Sharing/Plugin.php
new file mode 100644
index 000000000..354d06a56
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Sharing/Plugin.php
@@ -0,0 +1,342 @@
+<?php
+
+namespace Sabre\DAV\Sharing;
+
+use Sabre\DAV\Exception\BadRequest;
+use Sabre\DAV\Exception\Forbidden;
+use Sabre\DAV\INode;
+use Sabre\DAV\PropFind;
+use Sabre\DAV\Server;
+use Sabre\DAV\ServerPlugin;
+use Sabre\DAV\Xml\Property;
+use Sabre\DAV\Xml\Element\Sharee;
+use Sabre\HTTP\RequestInterface;
+use Sabre\HTTP\ResponseInterface;
+
+/**
+ * This plugin implements HTTP requests and properties related to:
+ *
+ * draft-pot-webdav-resource-sharing
+ *
+ * This specification allows people to share webdav resources with others.
+ *
+ * @copyright Copyright (C) 2007-2015 fruux GmbH. (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Plugin extends ServerPlugin {
+
+    const ACCESS_NOTSHARED = 0;
+    const ACCESS_SHAREDOWNER = 1;
+    const ACCESS_READ = 2;
+    const ACCESS_READWRITE = 3;
+    const ACCESS_NOACCESS = 4;
+
+    const INVITE_NORESPONSE = 1;
+    const INVITE_ACCEPTED = 2;
+    const INVITE_DECLINED = 3;
+    const INVITE_INVALID = 4;
+
+    /**
+     * Reference to SabreDAV server object.
+     *
+     * @var Sabre\DAV\Server
+     */
+    protected $server;
+
+    /**
+     * This method should return a list of server-features.
+     *
+     * This is for example 'versioning' and is added to the DAV: header
+     * in an OPTIONS response.
+     *
+     * @return array
+     */
+    function getFeatures() {
+
+        return ['resource-sharing'];
+
+    }
+
+    /**
+     * Returns a plugin name.
+     *
+     * Using this name other plugins will be able to access other plugins
+     * using \Sabre\DAV\Server::getPlugin
+     *
+     * @return string
+     */
+    function getPluginName() {
+
+        return 'sharing';
+
+    }
+
+    /**
+     * This initializes the plugin.
+     *
+     * This function is called by Sabre\DAV\Server, after
+     * addPlugin is called.
+     *
+     * This method should set up the required event subscriptions.
+     *
+     * @param Server $server
+     * @return void
+     */
+    function initialize(Server $server) {
+
+        $this->server = $server;
+
+        $server->xml->elementMap['{DAV:}share-resource'] = 'Sabre\\DAV\\Xml\\Request\\ShareResource';
+
+        array_push(
+            $server->protectedProperties,
+            '{DAV:}share-mode'
+        );
+
+        $server->on('method:POST',              [$this, 'httpPost']);
+        $server->on('propFind',                 [$this, 'propFind']);
+        $server->on('getSupportedPrivilegeSet', [$this, 'getSupportedPrivilegeSet']);
+        $server->on('onHTMLActionsPanel',       [$this, 'htmlActionsPanel']);
+        $server->on('onBrowserPostAction',      [$this, 'browserPostAction']);
+
+    }
+
+    /**
+     * Updates the list of sharees on a shared resource.
+     *
+     * The sharees  array is a list of people that are to be added modified
+     * or removed in the list of shares.
+     *
+     * @param string $path
+     * @param Sharee[] $sharees
+     * @return void
+     */
+    function shareResource($path, array $sharees) {
+
+        $node = $this->server->tree->getNodeForPath($path);
+
+        if (!$node instanceof ISharedNode) {
+
+            throw new Forbidden('Sharing is not allowed on this node');
+
+        }
+
+        // Getting ACL info
+        $acl = $this->server->getPlugin('acl');
+
+        // If there's no ACL support, we allow everything
+        if ($acl) {
+            $acl->checkPrivileges($path, '{DAV:}share');
+        }
+
+        foreach ($sharees as $sharee) {
+            // We're going to attempt to get a local principal uri for a share
+            // href by emitting the getPrincipalByUri event.
+            $principal = null;
+            $this->server->emit('getPrincipalByUri', [$sharee->href, &$principal]);
+            $sharee->principal = $principal;
+        }
+        $node->updateInvites($sharees);
+
+    }
+
+    /**
+     * This event is triggered when properties are requested for nodes.
+     *
+     * This allows us to inject any sharings-specific properties.
+     *
+     * @param PropFind $propFind
+     * @param INode $node
+     * @return void
+     */
+    function propFind(PropFind $propFind, INode $node) {
+
+        if ($node instanceof ISharedNode) {
+
+            $propFind->handle('{DAV:}share-access', function() use ($node) {
+
+                return new Property\ShareAccess($node->getShareAccess());
+
+            });
+            $propFind->handle('{DAV:}invite', function() use ($node) {
+
+                return new Property\Invite($node->getInvites());
+
+            });
+            $propFind->handle('{DAV:}share-resource-uri', function() use ($node) {
+
+                return new Property\Href($node->getShareResourceUri());
+
+            });
+
+        }
+
+    }
+
+    /**
+     * We intercept this to handle POST requests on shared resources
+     *
+     * @param RequestInterface $request
+     * @param ResponseInterface $response
+     * @return null|bool
+     */
+    function httpPost(RequestInterface $request, ResponseInterface $response) {
+
+        $path = $request->getPath();
+        $contentType = $request->getHeader('Content-Type');
+
+        // We're only interested in the davsharing content type.
+        if (strpos($contentType, 'application/davsharing+xml') === false) {
+            return;
+        }
+
+        $message = $this->server->xml->parse(
+            $request->getBody(),
+            $request->getUrl(),
+            $documentType
+        );
+
+        switch ($documentType) {
+
+            case '{DAV:}share-resource':
+
+                $this->shareResource($path, $message->sharees);
+                $response->setStatus(200);
+                // Adding this because sending a response body may cause issues,
+                // and I wanted some type of indicator the response was handled.
+                $response->setHeader('X-Sabre-Status', 'everything-went-well');
+
+                // Breaking the event chain
+                return false;
+
+            default :
+                throw new BadRequest('Unexpected document type: ' . $documentType . ' for this Content-Type');
+
+        }
+
+    }
+
+    /**
+     * This method is triggered whenever a subsystem reqeuests the privileges
+     * hat are supported on a particular node.
+     *
+     * We need to add a number of privileges for scheduling purposes.
+     *
+     * @param INode $node
+     * @param array $supportedPrivilegeSet
+     */
+    function getSupportedPrivilegeSet(INode $node, array &$supportedPrivilegeSet) {
+
+        if ($node instanceof ISharedNode) {
+            $supportedPrivilegeSet['{DAV:}share'] = [
+                'abstract'   => false,
+                'aggregates' => [],
+            ];
+        }
+    }
+
+    /**
+     * Returns a bunch of meta-data about the plugin.
+     *
+     * Providing this information is optional, and is mainly displayed by the
+     * Browser plugin.
+     *
+     * The description key in the returned array may contain html and will not
+     * be sanitized.
+     *
+     * @return array
+     */
+    function getPluginInfo() {
+
+        return [
+            'name'        => $this->getPluginName(),
+            'description' => 'This plugin implements WebDAV resource sharing',
+            'link'        => 'https://github.com/evert/webdav-sharing'
+        ];
+
+    }
+
+    /**
+     * This method is used to generate HTML output for the
+     * DAV\Browser\Plugin.
+     *
+     * @param INode $node
+     * @param string $output
+     * @param string $path
+     * @return bool|null
+     */
+    function htmlActionsPanel(INode $node, &$output, $path) {
+
+        if (!$node instanceof ISharedNode) {
+            return;
+        }
+
+        $aclPlugin = $this->server->getPlugin('acl');
+        if ($aclPlugin) {
+            if (!$aclPlugin->checkPrivileges($path, '{DAV:}share', \Sabre\DAVACL\Plugin::R_PARENT, false)) {
+                // Sharing is not permitted, we will not draw this interface.
+                return;
+            }
+        }
+
+        $output .= '<tr><td colspan="2"><form method="post" action="">
+            <h3>Share this resource</h3>
+            <input type="hidden" name="sabreAction" value="share" />
+            <label>Share with (uri):</label> <input type="text" name="href" placeholder="mailto:user@example.org"/><br />
+            <label>Access</label>
+                <select name="access">
+                    <option value="readwrite">Read-write</option>
+                    <option value="read">Read-only</option>
+                    <option value="no-access">Revoke access</option>
+                </select><br />
+             <input type="submit" value="share" />
+            </form>
+            </td></tr>';
+
+    }
+
+    /**
+     * This method is triggered for POST actions generated by the browser
+     * plugin.
+     *
+     * @param string $path
+     * @param string $action
+     * @param array $postVars
+     */
+    function browserPostAction($path, $action, $postVars) {
+
+        if ($action !== 'share') {
+            return;
+        }
+
+        if (empty($postVars['href'])) {
+            throw new BadRequest('The "href" POST parameter is required');
+        }
+        if (empty($postVars['access'])) {
+            throw new BadRequest('The "access" POST parameter is required');
+        }
+
+        $accessMap = [
+            'readwrite' => self::ACCESS_READWRITE,
+            'read'      => self::ACCESS_READ,
+            'no-access' => self::ACCESS_NOACCESS,
+        ];
+
+        if (!isset($accessMap[$postVars['access']])) {
+            throw new BadRequest('The "access" POST must be readwrite, read or no-access');
+        }
+        $sharee = new Sharee([
+            'href'   => $postVars['href'],
+            'access' => $accessMap[$postVars['access']],
+        ]);
+
+        $this->shareResource(
+            $path,
+            [$sharee]
+        );
+        return false;
+
+    }
+
+}
diff --git a/vendor/sabre/dav/lib/DAV/Tree.php b/vendor/sabre/dav/lib/DAV/Tree.php
index 4563f7c72..5d2792503 100644
--- a/vendor/sabre/dav/lib/DAV/Tree.php
+++ b/vendor/sabre/dav/lib/DAV/Tree.php
@@ -229,7 +229,7 @@ class Tree {
         // flushing the entire cache
         $path = trim($path, '/');
         foreach ($this->cache as $nodePath => $node) {
-            if ($nodePath == $path || strpos($nodePath, $path . '/') === 0)
+            if ($path === '' || $nodePath == $path || strpos($nodePath, $path . '/') === 0)
                 unset($this->cache[$nodePath]);
 
         }
diff --git a/vendor/sabre/dav/lib/DAV/Version.php b/vendor/sabre/dav/lib/DAV/Version.php
index f9331943a..5430b967c 100644
--- a/vendor/sabre/dav/lib/DAV/Version.php
+++ b/vendor/sabre/dav/lib/DAV/Version.php
@@ -14,6 +14,6 @@ class Version {
     /**
      * Full version number
      */
-    const VERSION = '3.1.3';
+    const VERSION = '3.2.0-beta1';
 
 }
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Element/Sharee.php b/vendor/sabre/dav/lib/DAV/Xml/Element/Sharee.php
new file mode 100644
index 000000000..dcfd7bd2e
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Xml/Element/Sharee.php
@@ -0,0 +1,199 @@
+<?php
+
+namespace Sabre\DAV\Xml\Element;
+
+use Sabre\DAV\Exception\BadRequest;
+use Sabre\DAV\Sharing\Plugin;
+use Sabre\DAV\Xml\Property\Href;
+use Sabre\DAV\Xml\Property\ShareAccess;
+use Sabre\Xml\Deserializer;
+use Sabre\Xml\Element;
+use Sabre\Xml\Reader;
+use Sabre\Xml\Writer;
+
+/**
+ * This class represents the {DAV:}sharee element.
+ *
+ * @copyright Copyright (C) fruux GmbH. (https://fruux.com/)
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Sharee implements Element {
+
+    /**
+     * A URL. Usually a mailto: address, could also be a principal url.
+     * This uniquely identifies the sharee.
+     *
+     * @var string
+     */
+    public $href;
+
+    /**
+     * A local principal path. The server will do its best to locate the
+     * principal uri based on the given uri. If we could find a local matching
+     * principal uri, this property will contain the value.
+     *
+     * @var string|null
+     */
+    public $principal;
+
+    /**
+     * A list of WebDAV properties that describe the sharee. This might for
+     * example contain a {DAV:}displayname with the real name of the user.
+     *
+     * @var array
+     */
+    public $properties = [];
+
+    /**
+     * Share access level. One of the Sabre\DAV\Sharing\Plugin::ACCESS
+     * constants.
+     *
+     * Can be one of:
+     *
+     * ACCESS_READ
+     * ACCESS_READWRITE
+     * ACCESS_SHAREDOWNER
+     * ACCESS_NOACCESS
+     *
+     * depending on context.
+     *
+     * @var int
+     */
+    public $access;
+
+    /**
+     * When a sharee is originally invited to a share, the sharer may add
+     * a comment. This will be placed in this property.
+     *
+     * @var string
+     */
+    public $comment;
+
+    /**
+     * The status of the invite, should be one of the
+     * Sabre\DAV\Sharing\Plugin::INVITE constants.
+     *
+     * @var int
+     */
+    public $inviteStatus;
+
+    /**
+     * Creates the object
+     *
+     * $properties will be used to populate all internal properties.
+     *
+     * @param array $properties
+     */
+    function __construct(array $properties = []) {
+
+        foreach ($properties as $k => $v) {
+
+            if (property_exists($this, $k)) {
+                $this->$k = $v;
+            } else {
+                throw new \InvalidArgumentException('Unknown property: ' . $k);
+            }
+
+        }
+
+    }
+
+    /**
+     * The xmlSerialize method is called during xml writing.
+     *
+     * Use the $writer argument to write its own xml serialization.
+     *
+     * An important note: do _not_ create a parent element. Any element
+     * implementing XmlSerializble should only ever write what's considered
+     * its 'inner xml'.
+     *
+     * The parent of the current element is responsible for writing a
+     * containing element.
+     *
+     * This allows serializers to be re-used for different element names.
+     *
+     * If you are opening new elements, you must also close them again.
+     *
+     * @param Writer $writer
+     * @return void
+     */
+    function xmlSerialize(Writer $writer) {
+
+
+        $writer->write([
+            new Href($this->href),
+            '{DAV:}prop'         => $this->properties,
+            '{DAV:}share-access' => new ShareAccess($this->access),
+        ]);
+        switch ($this->inviteStatus) {
+            case Plugin::INVITE_NORESPONSE :
+                $writer->writeElement('{DAV:}invite-noresponse');
+                break;
+            case Plugin::INVITE_ACCEPTED :
+                $writer->writeElement('{DAV:}invite-accepted');
+                break;
+            case Plugin::INVITE_DECLINED :
+                $writer->writeElement('{DAV:}invite-declined');
+                break;
+            case Plugin::INVITE_INVALID :
+                $writer->writeElement('{DAV:}invite-invalid');
+                break;
+        }
+
+    }
+
+    /**
+     * The deserialize method is called during xml parsing.
+     *
+     * This method is called statictly, this is because in theory this method
+     * may be used as a type of constructor, or factory method.
+     *
+     * Often you want to return an instance of the current class, but you are
+     * free to return other data as well.
+     *
+     * You are responsible for advancing the reader to the next element. Not
+     * doing anything will result in a never-ending loop.
+     *
+     * If you just want to skip parsing for this element altogether, you can
+     * just call $reader->next();
+     *
+     * $reader->parseInnerTree() will parse the entire sub-tree, and advance to
+     * the next element.
+     *
+     * @param Reader $reader
+     * @return mixed
+     */
+    static function xmlDeserialize(Reader $reader) {
+
+        // Temporarily override configuration
+        $reader->pushContext();
+        $reader->elementMap['{DAV:}share-access'] = 'Sabre\DAV\Xml\Property\ShareAccess';
+        $reader->elementMap['{DAV:}prop'] = 'Sabre\Xml\Deserializer\keyValue';
+
+        $elems = Deserializer\keyValue($reader, 'DAV:');
+
+        // Restore previous configuration
+        $reader->popContext();
+
+        $sharee = new self();
+        if (!isset($elems['href'])) {
+            throw new BadRequest('Every {DAV:}sharee must have a {DAV:}href child-element');
+        }
+        $sharee->href = $elems['href'];
+
+        if (isset($elems['prop'])) {
+            $sharee->properties = $elems['prop'];
+        }
+        if (isset($elems['comment'])) {
+            $sharee->comment = $elems['comment'];
+        }
+        if (!isset($elems['share-access'])) {
+            throw new BadRequest('Every {DAV:}sharee must have a {DAV:}share-access child element');
+        }
+        $sharee->access = $elems['share-access']->getValue();
+        return $sharee;
+
+    }
+
+}
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Property/Href.php b/vendor/sabre/dav/lib/DAV/Xml/Property/Href.php
index 538e98d0f..0027f72e1 100644
--- a/vendor/sabre/dav/lib/DAV/Xml/Property/Href.php
+++ b/vendor/sabre/dav/lib/DAV/Xml/Property/Href.php
@@ -7,6 +7,7 @@ use Sabre\DAV\Browser\HtmlOutputHelper;
 use Sabre\Xml\Element;
 use Sabre\Xml\Reader;
 use Sabre\Xml\Writer;
+use Sabre\Uri;
 
 /**
  * Href property
@@ -32,13 +33,6 @@ class Href implements Element, HtmlOutput {
     protected $hrefs;
 
     /**
-     * Automatically prefix the url with the server base directory
-     *
-     * @var bool
-     */
-    protected $autoPrefix = true;
-
-    /**
      * Constructor
      *
      * You must either pass a string for a single href, or an array of hrefs.
@@ -47,16 +41,13 @@ class Href implements Element, HtmlOutput {
      * and not relative to the servers base uri.
      *
      * @param string|string[] $href
-     * @param bool $autoPrefix
      */
-    function __construct($hrefs, $autoPrefix = true) {
+    function __construct($hrefs) {
 
         if (is_string($hrefs)) {
             $hrefs = [$hrefs];
         }
         $this->hrefs = $hrefs;
-        $this->autoPrefix = $autoPrefix;
-
 
     }
 
@@ -104,9 +95,7 @@ class Href implements Element, HtmlOutput {
     function xmlSerialize(Writer $writer) {
 
         foreach ($this->getHrefs() as $href) {
-            if ($this->autoPrefix) {
-                $href = $writer->contextUri . \Sabre\HTTP\encodePath($href);
-            }
+            $href = Uri\resolve($writer->contextUri, $href);
             $writer->writeElement('{DAV:}href', $href);
         }
 
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Property/Invite.php b/vendor/sabre/dav/lib/DAV/Xml/Property/Invite.php
new file mode 100644
index 000000000..0616ff113
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Xml/Property/Invite.php
@@ -0,0 +1,70 @@
+<?php
+
+namespace Sabre\DAV\Xml\Property;
+
+use Sabre\DAV\Sharing\Sharee;
+use Sabre\Xml\XmlSerializable;
+use Sabre\Xml\Writer;
+
+/**
+ * This class represents the {DAV:}invite property.
+ *
+ * This property is defined here:
+ * https://tools.ietf.org/html/draft-pot-webdav-resource-sharing-03#section-4.4.2
+ *
+ * This property is used by clients to determine who currently has access to
+ * a shared resource, what their access level is and what their invite status
+ * is.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/).
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class Invite implements XmlSerializable {
+
+    /**
+     * A list of sharees
+     *
+     * @var Sharee[]
+     */
+    public $sharees = [];
+
+    /**
+     * Creates the property.
+     *
+     * @param Sharee[] $sharees
+     */
+    function __construct(array $sharees) {
+
+        $this->sharees = $sharees;
+
+    }
+
+    /**
+     * The xmlSerialize method is called during xml writing.
+     *
+     * Use the $writer argument to write its own xml serialization.
+     *
+     * An important note: do _not_ create a parent element. Any element
+     * implementing XmlSerializble should only ever write what's considered
+     * its 'inner xml'.
+     *
+     * The parent of the current element is responsible for writing a
+     * containing element.
+     *
+     * This allows serializers to be re-used for different element names.
+     *
+     * If you are opening new elements, you must also close them again.
+     *
+     * @param Writer $writer
+     * @return void
+     */
+    function xmlSerialize(Writer $writer) {
+
+        foreach ($this->sharees as $sharee) {
+            $writer->writeElement('{DAV:}sharee', $sharee);
+        }
+
+    }
+
+}
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Property/LocalHref.php b/vendor/sabre/dav/lib/DAV/Xml/Property/LocalHref.php
new file mode 100644
index 000000000..76a27b95d
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Xml/Property/LocalHref.php
@@ -0,0 +1,48 @@
+<?php
+
+namespace Sabre\DAV\Xml\Property;
+
+use Sabre\HTTP;
+
+/**
+ * LocalHref property
+ *
+ * Like the Href property, this element represents {DAV:}href. The difference
+ * is that this is used stricly for paths on the server. The LocalHref property
+ * will prepare the path so it's a valid URI.
+ *
+ * These two objects behave identically:
+ *    new LocalHref($path)
+ *    new Href(\Sabre\HTTP\encodePath($path))
+ *
+ * LocalPath basically ensures that your spaces are %20, and everything that
+ * needs to be is uri encoded.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/)
+ * @author Evert Pot (http://www.rooftopsolutions.nl/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class LocalHref extends Href {
+
+    /**
+     * Constructor
+     *
+     * You must either pass a string for a single href, or an array of hrefs.
+     *
+     * If auto-prefix is set to false, the hrefs will be treated as absolute
+     * and not relative to the servers base uri.
+     *
+     * @param string|string[] $href
+     */
+    function __construct($hrefs) {
+
+        parent::__construct(array_map(
+            function($href) {
+                return \Sabre\HTTP\encodePath($href);
+            },
+            (array)$hrefs
+        ));
+
+    }
+
+}
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Property/ShareAccess.php b/vendor/sabre/dav/lib/DAV/Xml/Property/ShareAccess.php
new file mode 100644
index 000000000..f27af5415
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Xml/Property/ShareAccess.php
@@ -0,0 +1,143 @@
+<?php
+
+namespace Sabre\DAV\Xml\Property;
+
+use Sabre\DAV\Sharing\Plugin as SharingPlugin;
+use Sabre\DAV\Exception\BadRequest;
+use Sabre\Xml\Element;
+use Sabre\Xml\Reader;
+use Sabre\Xml\Writer;
+
+/**
+ * This class represents the {DAV:}share-access property.
+ *
+ * This property is defined here:
+ * https://tools.ietf.org/html/draft-pot-webdav-resource-sharing-03#section-4.4.1
+ *
+ * This property is used to indicate if a resource is a shared resource, and
+ * whether the instance of the shared resource is the original instance, or
+ * an instance belonging to a sharee.
+ *
+ * @copyright Copyright (C) fruux GmbH (https://fruux.com/).
+ * @author Evert Pot (http://evertpot.com/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class ShareAccess implements Element {
+
+    /**
+     * Either SHARED or SHAREDOWNER
+     *
+     * @var int
+     */
+    protected $value;
+
+    /**
+     * Creates the property.
+     *
+     * The constructor value must be one of the
+     * \Sabre\DAV\Sharing\Plugin::ACCESS_ constants.
+     *
+     * @param int $shareAccess
+     */
+    function __construct($shareAccess) {
+
+        $this->value = $shareAccess;
+
+    }
+
+    /**
+     * Returns the current value.
+     *
+     * @return int
+     */
+    function getValue() {
+
+        return $this->value;
+
+    }
+
+    /**
+     * The xmlSerialize method is called during xml writing.
+     *
+     * Use the $writer argument to write its own xml serialization.
+     *
+     * An important note: do _not_ create a parent element. Any element
+     * implementing XmlSerializble should only ever write what's considered
+     * its 'inner xml'.
+     *
+     * The parent of the current element is responsible for writing a
+     * containing element.
+     *
+     * This allows serializers to be re-used for different element names.
+     *
+     * If you are opening new elements, you must also close them again.
+     *
+     * @param Writer $writer
+     * @return void
+     */
+    function xmlSerialize(Writer $writer) {
+
+        switch ($this->value) {
+
+            case SharingPlugin::ACCESS_NOTSHARED :
+                $writer->writeElement('{DAV:}not-shared');
+                break;
+            case SharingPlugin::ACCESS_SHAREDOWNER :
+                $writer->writeElement('{DAV:}shared-owner');
+                break;
+            case SharingPlugin::ACCESS_READ :
+                $writer->writeElement('{DAV:}read');
+                break;
+            case SharingPlugin::ACCESS_READWRITE :
+                $writer->writeElement('{DAV:}read-write');
+                break;
+            case SharingPlugin::ACCESS_NOACCESS :
+                $writer->writeElement('{DAV:}no-access');
+                break;
+
+        }
+
+    }
+
+    /**
+     * The deserialize method is called during xml parsing.
+     *
+     * This method is called statictly, this is because in theory this method
+     * may be used as a type of constructor, or factory method.
+     *
+     * Often you want to return an instance of the current class, but you are
+     * free to return other data as well.
+     *
+     * You are responsible for advancing the reader to the next element. Not
+     * doing anything will result in a never-ending loop.
+     *
+     * If you just want to skip parsing for this element altogether, you can
+     * just call $reader->next();
+     *
+     * $reader->parseInnerTree() will parse the entire sub-tree, and advance to
+     * the next element.
+     *
+     * @param Reader $reader
+     * @return mixed
+     */
+    static function xmlDeserialize(Reader $reader) {
+
+        $elems = $reader->parseInnerTree();
+        foreach ($elems as $elem) {
+            switch ($elem['name']) {
+                case '{DAV:}not-shared' :
+                    return new self(SharingPlugin::ACCESS_NOTSHARED);
+                case '{DAV:}sharedowner' :
+                    return new self(SharingPlugin::ACCESS_SHAREDOWNER);
+                case '{DAV:}read' :
+                    return new self(SharingPlugin::ACCESS_READ);
+                case '{DAV:}read-write' :
+                    return new self(SharingPlugin::ACCESS_READWRITE);
+                case '{DAV:}no-access' :
+                    return new self(SharingPlugin::ACCESS_NOACCESS);
+            }
+        }
+        throw new BadRequest('Invalid value for {DAV:}share-access element');
+
+    }
+}
diff --git a/vendor/sabre/dav/lib/DAV/Xml/Request/ShareResource.php b/vendor/sabre/dav/lib/DAV/Xml/Request/ShareResource.php
new file mode 100644
index 000000000..965e5857c
--- /dev/null
+++ b/vendor/sabre/dav/lib/DAV/Xml/Request/ShareResource.php
@@ -0,0 +1,81 @@
+<?php
+
+namespace Sabre\DAV\Xml\Request;
+
+use Sabre\Xml\Reader;
+use Sabre\Xml\XmlDeserializable;
+use Sabre\DAV\Xml\Element\Sharee;
+
+/**
+ * ShareResource request parser.
+ *
+ * This class parses the {DAV:}share-resource POST request as defined in:
+ *
+ * https://tools.ietf.org/html/draft-pot-webdav-resource-sharing-01#section-5.3.2.1
+ *
+ * @copyright Copyright (C) 2007-2015 fruux GmbH (https://fruux.com/).
+ * @author Evert Pot (http://www.rooftopsolutions.nl/)
+ * @license http://sabre.io/license/ Modified BSD License
+ */
+class ShareResource implements XmlDeserializable {
+
+    /**
+     * The list of new people added or updated or removed from the share.
+     *
+     * @var Sharee[]
+     */
+    public $sharees = [];
+
+    /**
+     * Constructor
+     *
+     * @param Sharee[] $sharees
+     */
+    function __construct(array $sharees) {
+
+        $this->sharees = $sharees;
+
+    }
+
+    /**
+     * The deserialize method is called during xml parsing.
+     *
+     * This method is called statictly, this is because in theory this method
+     * may be used as a type of constructor, or factory method.
+     *
+     * Often you want to return an instance of the current class, but you are
+     * free to return other data as well.
+     *
+     * You are responsible for advancing the reader to the next element. Not
+     * doing anything will result in a never-ending loop.
+     *
+     * If you just want to skip parsing for this element altogether, you can
+     * just call $reader->next();
+     *
+     * $reader->parseInnerTree() will parse the entire sub-tree, and advance to
+     * the next element.
+     *
+     * @param Reader $reader
+     * @return mixed
+     */
+    static function xmlDeserialize(Reader $reader) {
+
+        $elems = $reader->parseInnerTree([
+            '{DAV:}sharee'       => 'Sabre\DAV\Xml\Element\Sharee',
+            '{DAV:}share-access' => 'Sabre\DAV\Xml\Property\ShareAccess',
+            '{DAV:}prop'         => 'Sabre\Xml\Deserializer\keyValue',
+        ]);
+
+        $sharees = [];
+
+        foreach ($elems as $elem) {
+            if ($elem['name'] !== '{DAV:}sharee') continue;
+            $sharees[] = $elem['value'];
+
+        }
+
+        return new self($sharees);
+
+    }
+
+}