From 16e14076213d1b4cf5e9a0d6c31a0ac0f6b80967 Mon Sep 17 00:00:00 2001
From: Christian Boltz <postfixadmin@cboltz.de>
Date: Tue, 1 Nov 2016 15:45:45 +0000
Subject: [PATCH] db_where_clause(): allow NULL and NOTNULL searchmodes

git-svn-id: https://svn.code.sf.net/p/postfixadmin/code/trunk@1878 a1433add-5e2c-0410-b055-b7f2511e0802
---
 functions.inc.php | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/functions.inc.php b/functions.inc.php
index 5ff4ab32..e60a853a 100644
--- a/functions.inc.php
+++ b/functions.inc.php
@@ -1688,11 +1688,13 @@ function db_in_clause($field, $values) {
  * db_where_clause
  * Action: builds and returns a WHERE clause for database queries. All given conditions will be AND'ed.
  * Call: db_where_clause (array $conditions, array $struct)
- * param array $conditios: array('field' => 'value', 'field2' => 'value2, ...)
+ * param array $condition: array('field' => 'value', 'field2' => 'value2, ...)
  * param array $struct - field structure, used for automatic bool conversion
  * param string $additional_raw_where - raw sniplet to include in the WHERE part - typically needs to start with AND
  * param array $searchmode - operators to use (=, <, > etc.) - defaults to = if not specified for a field (see 
  *                           $allowed_operators for available operators)
+ *                           Note: the $searchmode operator will only be used if a $condition for that field is set.
+ *                                 This also means you'll need to set a (dummy) condition for NULL and NOTNULL.
  */
 function db_where_clause($condition, $struct, $additional_raw_where = '', $searchmode = array()) {
     if (!is_array($condition)) {
@@ -1705,7 +1707,7 @@ function db_where_clause($condition, $struct, $additional_raw_where = '', $searc
         die('db_where_cond: parameter $struct is not an array!');
     }
 
-    $allowed_operators = explode(' ', '< > >= <= = != <> CONT LIKE');
+    $allowed_operators = explode(' ', '< > >= <= = != <> CONT LIKE NULL NOTNULL');
     $where_parts = array();
     $having_parts = array();
 
@@ -1726,7 +1728,15 @@ function db_where_clause($condition, $struct, $additional_raw_where = '', $searc
                 die('db_where_clause: Invalid searchmode for ' . $field);
             }
         }
-        $querypart = $field . $operator . "'" . escape_string($value) . "'";
+
+        if ($operator == "NULL") {
+            $querypart = $field . ' IS NULL';
+        } elseif ($operator == "NOTNULL") {
+            $querypart = $field . ' IS NOT NULL';
+        } else {
+            $querypart = $field . $operator . "'" . escape_string($value) . "'";
+        }
+
         if($struct[$field]['select'] != '') {
             $having_parts[$field] = $querypart;
         } else {