Add support for extra sendmail arguments

Author: cez81

conf/app.ini

@@ -327,6 +327,8 @@ SEND_AS_PLAIN_TEXT = false
 USE_SENDMAIL = false
 ; Specify an alternative sendmail binary
 SENDMAIL_PATH = sendmail
+; Specify any extra sendmail arguments
+SENDMAIL_ARGS =
 
 [cache]
 ; Either "memory", "redis", or "memcache", default is "memory"

modules/mailer/mailer.go

@@ -209,6 +209,7 @@ func (s *sendmailSender) Send(from string, to []string, msg io.WriterTo) error {
 	var waitError error
 
 	args := []string{"-F", from, "-i"}
+	args = append(args, setting.MailService.SendmailArgs)
 	args = append(args, to...)
 	log.Trace("Sending with: %s %v", setting.MailService.SendmailPath, args)
 	cmd := exec.Command(setting.MailService.SendmailPath, args...)

modules/setting/setting.go

@@ -1326,6 +1326,7 @@ type Mailer struct {
 	// Sendmail sender
 	UseSendmail  bool
 	SendmailPath string
+	SendmailArgs string
 }
 
 var (
@@ -1357,6 +1358,7 @@ func newMailService() {
 
 		UseSendmail:  sec.Key("USE_SENDMAIL").MustBool(),
 		SendmailPath: sec.Key("SENDMAIL_PATH").MustString("sendmail"),
+		SendmailArgs: sec.Key("SENDMAIL_ARGS").MustString(""),
 	}
 	MailService.From = sec.Key("FROM").MustString(MailService.User)