Fix handling of 'mailto' and 'error' arguments in message_before_send hook (#5347)

Conflicts:
	program/lib/Roundcube/rcube.php

CHANGELOG

@@ -25,6 +25,7 @@ CHANGELOG Roundcube Webmail
 - Fix conflict in new_user_dialog and password_force_new_user settings (#5275)
 - Don't create multipart/alternative messages with empty text/plain part (#5283)
 - Use contact_search_name format in popup on results in compose contacts search
+- Fix handling of 'mailto' and 'error' arguments in message_before_send hook (#5347)
 
 RELEASE 1.2.0
 -------------

program/lib/Roundcube/rcube.php

@@ -1602,10 +1602,14 @@ class rcube
             // unset To,Subject headers because they will be added by the mail() function
             $header_str = $this->message_head($message, array('To', 'Subject'));
 
+            if (is_array($mailto)) {
+                $mailto = implode(', ', $mailto);
+            }
+
             // #1485779
             if (strtoupper(substr(PHP_OS, 0, 3)) === 'WIN') {
-                if (preg_match_all('/<([^@]+@[^>]+)>/', $headers['To'], $m)) {
-                    $headers['To'] = implode(', ', $m[1]);
+                if (preg_match_all('/<([^@]+@[^>]+)>/', $mailto, $m)) {
+                    $mailto = implode(', ', $m[1]);
                 }
             }
 
@@ -1618,9 +1622,9 @@ class rcube
                     true, false);
             }
             else {
-                $delim   = $this->config->header_delimiter();
-                $to      = $headers['To'];
-                $subject = $headers['Subject'];
+                $delim      = $this->config->header_delimiter();
+                $to         = $mailto;
+                $subject    = $headers['Subject'];
                 $header_str = rtrim($header_str);
 
                 if ($delim != "\r\n") {

program/steps/mail/sendmail.inc

@@ -540,10 +540,16 @@ if (!$savedraft && !$saveonly) {
             unlink($mailbody_file);
         }
 
-        if ($smtp_error)
-            $OUTPUT->show_message($smtp_error['label'], 'error', $smtp_error['vars']); 
-        else
-            $OUTPUT->show_message('sendingfailed', 'error'); 
+        if ($smtp_error && is_string($smtp_error)) {
+            $OUTPUT->show_message($smtp_error, 'error');
+        }
+        else if ($smtp_error && !empty($smtp_error['label'])) {
+            $OUTPUT->show_message($smtp_error['label'], 'error', $smtp_error['vars']);
+        }
+        else {
+            $OUTPUT->show_message('sendingfailed', 'error');
+        }
+
         $OUTPUT->send('iframe');
     }