initial implementation for symlinks, see #89

In order to make this work you need to compile your own PHP from
https://github.com/thekid/php-src branch rfc/linking_in_stream_wrappers

src/main/php/org/bovigo/vfs/Symlink.php

@@ -0,0 +1,310 @@
+<?php
+/**
+ * This file is part of vfsStream.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ *
+ * @package  org\bovigo\vfs
+ */
+namespace org\bovigo\vfs;
+/**
+ * Represents a symbolic link.
+ *
+ * @since  1.?.0
+ */
+class Symlink implements vfsStreamContent
+{
+    /**
+     * name of the link
+     *
+     * @type  string
+     */
+    private $name;
+    /**
+     * target where link points to
+     *
+     * @type  \org\bovigo\vfs\vfsStreamContent
+     */
+    private $target;
+    /**
+     * path to to this content
+     *
+     * @type  string
+     */
+    private $parentPath;
+
+    /**
+     * constructor
+     *
+     * @param  string                            $name    name of link
+     * @param  \org\bovigo\vfs\vfsStreamContent  $target  target where link points to
+     */
+    public function __construct($name, vfsStreamContent $target)
+    {
+        $this->name   = $name;
+        $this->target = $target;
+    }
+
+    /**
+     * resolves the link
+     *
+     * @return  \org\bovigo\vfs\vfsStreamContent
+     */
+    public function resolve()
+    {
+        return $this->target;
+    }
+
+    public function targetName()
+    {
+        return $this->target->getName();
+    }
+
+    /**
+     * returns the file name of the content
+     *
+     * @return  string
+     */
+    public function getName()
+    {
+        return $this->name;
+    }
+
+    /**
+     * renames the content
+     *
+     * @param  string  $newName
+     */
+    public function rename($newName)
+    {
+        $this->name = $newName;
+    }
+
+    /**
+     * checks whether the container can be applied to given name
+     *
+     * @param   string  $name
+     * @return  bool
+     */
+    public function appliesTo($name)
+    {
+        if ($name === $this->name) {
+            return true;
+        }
+
+        $segment_name = $this->name.'/';
+        return (strncmp($segment_name, $name, strlen($segment_name)) == 0);
+    }
+
+    /**
+     * returns the type of the container
+     *
+     * @return  int
+     */
+    public function getType()
+    {
+        return vfsStreamContent::TYPE_LINK;
+    }
+
+    /**
+     * returns size of content
+     *
+     * @return  int
+     */
+    public function size()
+    {
+        return $this->target->size();
+    }
+
+    /**
+     * sets the last modification time of the stream content
+     *
+     * @param   int  $filemtime
+     * @return  vfsStreamContent
+     */
+    public function lastModified($filemtime)
+    {
+        $this->target->lastModified($filemtime);
+        return $this;
+    }
+
+    /**
+     * returns the last modification time of the stream content
+     *
+     * @return  int
+     */
+    public function filemtime()
+    {
+        return $this->target->filemtime();
+    }
+
+    /**
+     * adds content to given container
+     *
+     * @param   vfsStreamContainer  $container
+     * @return  vfsStreamContent
+     */
+    public function at(vfsStreamContainer $container)
+    {
+        $container->addChild($this);
+        return $this;
+    }
+
+    /**
+     * change file mode to given permissions
+     *
+     * @param   int  $permissions
+     * @return  vfsStreamContent
+     */
+    public function chmod($permissions)
+    {
+        $this->target->chmod($permissions);
+        return $this;
+    }
+
+    /**
+     * returns permissions
+     *
+     * @return  int
+     */
+    public function getPermissions()
+    {
+        return $this->target->getPermissions();
+    }
+
+    /**
+     * checks whether content is readable
+     *
+     * @param   int   $user   id of user to check for
+     * @param   int   $group  id of group to check for
+     * @return  bool
+     */
+    public function isReadable($user, $group)
+    {
+        # self or target?
+    }
+
+    /**
+     * checks whether content is writable
+     *
+     * @param   int   $user   id of user to check for
+     * @param   int   $group  id of group to check for
+     * @return  bool
+     */
+    public function isWritable($user, $group)
+    {
+        # self or target?
+    }
+
+    /**
+     * checks whether content is executable
+     *
+     * @param   int   $user   id of user to check for
+     * @param   int   $group  id of group to check for
+     * @return  bool
+     */
+    public function isExecutable($user, $group)
+    {
+        # self or target?
+    }
+
+    /**
+     * change owner of file to given user
+     *
+     * @param   int  $user
+     * @return  vfsStreamContent
+     */
+    public function chown($user)
+    {
+        # self or target?
+    }
+
+    /**
+     * checks whether file is owned by given user
+     *
+     * @param   int  $user
+     * @return  bool
+     */
+    public function isOwnedByUser($user)
+    {
+        # self or target?
+    }
+
+    /**
+     * returns owner of file
+     *
+     * @return  int
+     */
+    public function getUser()
+    {
+        # self or target?
+    }
+
+    /**
+     * change owner group of file to given group
+     *
+     * @param   int  $group
+     * @return  vfsStreamContent
+     */
+    public function chgrp($group)
+    {
+        # self or target?
+    }
+
+    /**
+     * checks whether file is owned by group
+     *
+     * @param   int   $group
+     * @return  bool
+     */
+    public function isOwnedByGroup($group)
+    {
+        # self or target?
+    }
+
+    /**
+     * returns owner group of file
+     *
+     * @return  int
+     */
+    public function getGroup()
+    {
+        # self or target?
+    }
+
+    /**
+     * sets parent path
+     *
+     * @param  string  $parentPath
+     * @internal  only to be set by parent
+     */
+    public function setParentPath($parentPath)
+    {
+        $this->parentPath = $parentPath;
+    }
+
+    /**
+     * returns path to this content
+     *
+     * @return  string
+     */
+    public function path()
+    {
+        if (null === $this->parentPath) {
+            return $this->name;
+        }
+
+        return $this->parentPath . '/' . $this->name;
+    }
+
+    /**
+     * returns complete vfsStream url for this content
+     *
+     * @return  string
+     */
+    public function url()
+    {
+        return vfsStream::url($this->path());
+    }
+}

src/main/php/org/bovigo/vfs/vfsStream.php

@@ -339,13 +339,26 @@ public static function newDirectory($name, $permissions = null)
      *
      * @param   string  $name           name of the block device
      * @param   int     $permissions    permissions of block to create
-     * @return vfsStreamBlock
+     * @return  \org\bovigo\vfs\vfsStreamBlock
      */
     public static function newBlock($name, $permissions = null)
     {
         return new vfsStreamBlock($name, $permissions);
     }
 
+    /**
+     * returns a new symbolic link with given name pointing to target
+     *
+     * @param   string  $name
+     * @param   \org\bovigo\vfs\vfsStreamContent $target
+     * @return  \org\bovigo\vfs\Symlink
+     * @since   1.?.0
+     */
+    public static function newSymlink($name, vfsStreamContent $target)
+    {
+        return new Symlink($name, $target);
+    }
+
     /**
      * returns current user
      *

src/main/php/org/bovigo/vfs/vfsStreamContent.php

@@ -30,8 +30,7 @@ interface vfsStreamContent
      *
      * @see  getType();
      */
-    #const TYPE_LINK = 0120000;
-
+    const TYPE_LINK = 0120000;
     /**
      * stream content type: block
      *
@@ -211,4 +210,4 @@ public function path();
      */
     public function url();
 }
-?>
+

src/main/php/org/bovigo/vfs/vfsStreamWrapper.php

@@ -977,5 +977,20 @@ public function url_stat($path, $flags)
                     );
         return array_merge(array_values($fileStat), $fileStat);
     }
+
+    public function url_readlink($path)
+    {
+        $content = $this->getContent($this->resolvePath(vfsStream::path($path)));
+        if (null === $content) {
+            trigger_error(' Does not exist: ' . $path, E_USER_WARNING);
+            return false;
+        }
+
+        if ($content->getType() !== vfsStreamContent::TYPE_LINK) {
+            trigger_error(' Not a link: ' . $path, E_USER_WARNING);
+            return false;
+        }
+
+        return $content->targetName();
+    }
 }
-?>