Avoid PHP Notices on non-standard mail header lines that don't contain a column, reporting warning to syslog.

Author: onlime

CHANGELOG.md

@@ -1,5 +1,9 @@
 # CHANGELOG
 
+## 1.0.6 (UNRELEASED)
+
+- Avoid PHP Notices on non-standard mail header lines that don't contain a column, reporting warning to syslog.
+
 ## 1.0.5 (2019-10-29)
 
 - Fix for newline after `whoami` shell output, which broke message logging to syslog.

app/StdinMailParser.php

@@ -108,7 +108,11 @@ public function getParsedHeaderArr()
         $headerLines = explode(PHP_EOL, $this->_header);
         $headerArr   = [];
         foreach ($headerLines as $line) {
-            list($key, $value) = explode(":", $line);
+            list($key, $value) = @explode(":", $line);
+            if (is_null($value)) {
+                // avoid 'PHP Notice:  Undefined offset: 1' on header line without colon
+                syslog(LOG_WARNING, sprintf('%s: Could not parse mail header line: %s', __METHOD__, $line));
+            }
             $key   = strtolower(trim($key));
             $value = trim($value);
             if (isset($headerArr[$key]) && !in_array($key, $this->_rfc5322MultiHeaders)) {