From df4676daf1264897f59f2b7e3ac45d31ca866b25 Mon Sep 17 00:00:00 2001
From: Roly Rudy Gutierrez Pinto <gproly@gmail.com>
Date: Tue, 19 Feb 2019 12:47:43 -0400
Subject: [PATCH] PMC-508

---
 thirdparty/creole/drivers/mysqli/MySQLiResultSet.php |  4 +++-
 thirdparty/pear/DB/mysqli.php                        | 12 ++++++++++--
 workflow/engine/classes/class.webdav.php             |  6 +++++-
 3 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/thirdparty/creole/drivers/mysqli/MySQLiResultSet.php b/thirdparty/creole/drivers/mysqli/MySQLiResultSet.php
index fecfd6361..32a9ddaac 100644
--- a/thirdparty/creole/drivers/mysqli/MySQLiResultSet.php
+++ b/thirdparty/creole/drivers/mysqli/MySQLiResultSet.php
@@ -98,7 +98,9 @@ class MySQLiResultSet extends ResultSetCommon implements ResultSet {
      */
     public function close()
     {
-        @mysqli_free_result($this->result);
+        if (is_resource($this->result)) {
+            @mysqli_free_result($this->result);
+        }
         $this->fields = array();
     }
 
diff --git a/thirdparty/pear/DB/mysqli.php b/thirdparty/pear/DB/mysqli.php
index 3c0fd1db4..7bd138855 100644
--- a/thirdparty/pear/DB/mysqli.php
+++ b/thirdparty/pear/DB/mysqli.php
@@ -379,7 +379,13 @@ class DB_mysqli extends DB_common
 # need to come up with different means for next line
 # since $result is object (int)$result won't fly...
 //        unset($this->num_rows[(int)$result]);
-        return @mysqli_free_result($result);
+        
+        //for compatibility the method must return a boolean.
+        if (is_resource($result)) {
+            @mysqli_free_result($result);
+            return true;
+        }
+        return false;
     }
 
     // }}}
@@ -902,7 +908,9 @@ class DB_mysqli extends DB_common
 
         // free the result only if we were called on a table
         if ($got_string) {
-            @mysqli_free_result($id);
+            if (is_resource($id)) {
+                @mysqli_free_result($id);
+            }
         }
         return $res;
     }
diff --git a/workflow/engine/classes/class.webdav.php b/workflow/engine/classes/class.webdav.php
index 4fd290379..d4d9503d6 100644
--- a/workflow/engine/classes/class.webdav.php
+++ b/workflow/engine/classes/class.webdav.php
@@ -944,6 +944,8 @@ class ProcessMakerWebDav extends HTTP_WebDAV_Server
      *
      * @param string resource path to check for locks
      * @return bool true on success
+     * @link https://wiki.processmaker.com/index.php/WebDAV
+     * @deprecated
      */
     public function checkLock($path)
     {
@@ -959,7 +961,9 @@ class ProcessMakerWebDav extends HTTP_WebDAV_Server
 
         if ($res) {
             $row = mysqli_fetch_array($res);
-            mysqli_free_result($res);
+            if (is_resource($res)) {
+                mysqli_free_result($res);
+            }
 
             if ($row) {
                 $result = array("type" => "write", "scope" => $row["exclusivelock"] ? "exclusive" : "shared", "depth" => 0, "owner" => $row['owner'], "token" => $row['token'], "expires" => $row['expires']