--- a/lib/Protobuf-PHP/library/DrSlump/Protobuf/Compiler/CommentsParser.php
+++ b/lib/Protobuf-PHP/library/DrSlump/Protobuf/Compiler/CommentsParser.php
@@ -1,1 +1,136 @@
+<?php
 
+namespace DrSlump\Protobuf\Compiler;
+
+class CommentsParser
+{
+    /** @var array - Hold a mapping of entity => comment */
+    protected $comments = array();
+
+    /** @var array - Define tokenizer regular expressions */
+    protected $tokens = array(
+        'comment' => '/\*([\S\s]+?)\*/',
+        'package' => 'package\s+([A-Z0-9_]+)',
+        'struct'  => '(?:message|enum|service)\s+([A-Z0-9_]+)',
+        'close'   => '}',
+        'field'   => '(?:required|optional|repeated)\s+[^=]+=\s*([0-9]+)[^;]*;',
+        'rpc'     => 'rpc\s+([A-Z0-9_]+)[^;]+'
+    );
+
+    /** @var string - The regular expresion for the tokenizer */
+    protected $regexp;
+
+    public function __construct()
+    {
+        // Generate a regular expression for all tokens
+        $regexp = array();
+        foreach ($this->tokens as $token=>$exp) {
+            $regexp[] = '(?<' . $token . '>' . $exp . ')';
+        }
+        $this->regexp = '@' . implode('|', $regexp) . '@i';
+    }
+
+    /**
+     * Reset the currently stored comments
+     */
+    public function reset()
+    {
+        $this->comments = array();
+    }
+
+    /**
+     * Parse a Proto file source code to fetch comments
+     *
+     * @param string $src
+     */
+    public function parse($src)
+    {
+        // Build an stream of tokens from the regular expression
+        $tokens = array();
+        $offset = 0;
+        while (preg_match($this->regexp, $src, $m, PREG_OFFSET_CAPTURE, $offset)) {
+            foreach ($this->tokens as $k=>$v) {
+                if (!empty($m[$k]) && 0 < strlen($m[$k][0])) {
+                    $tokens[] = array(
+                        'token' => $k,
+                        'value' => array_shift(array_pop($m)),
+                    );
+                }
+            }
+            $offset = $m[0][1] + strlen($m[0][0]);
+        }
+
+        // Parse the tokens stream to assign comments
+        $comment = null;
+        $stack = array();
+        foreach ($tokens as $token) {
+            if ($token['token'] === 'comment') {
+                $comment = $token['value'];
+            } elseif ($token['token'] === 'package') {
+                $stack[] = $token['value'];
+                $comment = null;
+            } elseif ($token['token'] === 'struct') {
+                $stack[] = $token['value'];
+                if ($comment) {
+                    $this->setComment(implode('.', $stack), $comment);
+                    $comment = null;
+                }
+            } elseif ($token['token'] === 'close') {
+                array_pop($stack);
+                $comment = null;
+            } elseif ($token['token'] === 'field' || $token['token'] === 'rpc') {
+                if ($comment) {
+                    $this->setComment(implode('.', $stack) . '.' . $token['value'], $comment);
+                    $comment = null;
+                }
+            }
+        }
+    }
+
+    /**
+     * Set a comment for the given identifier. The identifier is composed
+     * of the package, followed by the message (and nested messages). Field
+     * comments are suffixed with the tag number.
+     *
+     * @example
+     *
+     *     $this->setComment('MyPackage.MyMessage.Nested.2', 'field comment');
+     *
+     * @param string $ident
+     * @param string $comment
+     */
+    public function setComment($ident, $comment)
+    {
+        $comment = str_replace("\r\n", "\n", $comment);
+        $comment = preg_replace('/^[\s\*]+/m', '', $comment);
+        $comment = trim($comment, "* \n");
+        $this->comments[$ident] = $comment;
+    }
+
+    /**
+     * Get the comment for a given identifier
+     *
+     * @param string $ident
+     * @return string|null
+     */
+    public function getComment($ident)
+    {
+        return isset($this->comments[$ident])
+               ? $this->comments[$ident]
+               : null;
+    }
+
+    /**
+     * Checks if a comment exists for a given identifier
+     *
+     * @param string $ident
+     * @return bool
+     */
+    public function hasComment($ident)
+    {
+        return isset($this->comments[$ident]);
+    }
+}
+
+
+