[PATCH] logger: do not exit when socket errors are not enforced

[PATCH] logger: do not exit when socket errors are not enforced

[Sami Kerola]

The libc openlog(3) does not have error detection whether unix socket
could be opened.  As a side effect that made it possible to use logger
even if syslogd was not running.  Of course user message in these cases
were lost.  This change makes the logger do behave similar way again, so
that sysvinit scripts can successfully pipe messages to logger when ever.

Addresses: https://bugs.debian.org/787864
Addresses: https://bugs.debian.org/790875
Reported-by: Andreas Beckmann <anbe@debian.org>
Reported-by: Andreas Henriksson <andreas@fatal.se>
Tested-by: Robie Basak <robie.basak@ubuntu.com>
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
---
 misc-utils/logger.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/misc-utils/logger.c b/misc-utils/logger.c
index 8908dfc..9947b75 100644
--- a/misc-utils/logger.c
+++ b/misc-utils/logger.c
@@ -242,9 +242,10 @@ static int unix_socket(struct logger_ctl *ctl, const char *path, const int socke
 		if (ctl->unix_socket_errors)
 			err(EXIT_FAILURE, _("socket %s"), path);
 		else
-			/* See --socket-errors manual page entry for
-			 * explanation of this strange exit.  */
-			exit(EXIT_SUCCESS);
+			/* openlog(3) compatibility, socket errors are
+			 * not reported, but ignored silently */
+			ctl->noact = 1;
+			return -1;
 	}
 	return fd;
 }
@@ -685,7 +686,7 @@ static void logger_stdin(struct logger_ctl *ctl)
 
 static void logger_close(const struct logger_ctl *ctl)
 {
-	if (close(ctl->fd) != 0)
+	if (ctl->fd != -1 && close(ctl->fd) != 0)
 		err(EXIT_FAILURE, _("close failed"));
 	free(ctl->hdr);
 }
-- 
2.4.6

Re: [PATCH] logger: do not exit when socket errors are not enforced

[Karel Zak]

On Sun, Jul 19, 2015 at 09:19:12PM +0100, Sami Kerola wrote:
> The libc openlog(3) does not have error detection whether unix socket
> could be opened.  As a side effect that made it possible to use logger
> even if syslogd was not running.  Of course user message in these cases
> were lost.  This change makes the logger do behave similar way again, so
> that sysvinit scripts can successfully pipe messages to logger when ever.

Applied, thanks 
-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com