[syslog-ng][PATCH] please test: syslog-ng message mangling fix

[Balazs Scheidler]

On Thu, Aug 08, 2002 at 11:23:08AM +0200, Balazs Scheidler wrote:
> Hi,
> 
> This patch should fix the message mangling problems you might have
> encountered. As the log parsing routines are quite critical I don't want to
> release this patch without testing on most platforms. It seems to work on
> Linux for me, but tests from more exotic platforms are welcome.
> 
> (the problem this patch fixes occurs only if you have messages longer than
> the default limit. the limit can be changed by log_msg_size)

Thinking a bit more this patch breaks when receiving UDP syslog from a
devices which do not terminate messages with nl or \0.

The best solution though is to increase log_msg_size() to be longer than the
longest expected message.

A fixed patch below (still against plain 1.5.19 so you need to reverse the
previous patch):

Index: sources.c
===================================================================
RCS file: /var/cvs/syslog-ng/syslog-ng/src/sources.c,v
retrieving revision 1.34
diff -u -r1.34 sources.c
--- sources.c	18 Jul 2002 13:18:02 -0000	1.34
+++ sources.c	8 Aug 2002 10:01:18 -0000
@@ -79,10 +80,11 @@
 	CAST(log_reader, closure, *h);
 	UINT8 *eol, *start;
 	UINT32 length;
-	int n;
+	int n, start_pos;
 	char sabuf[256];
 	size_t salen = sizeof(sabuf);
 
+	start_pos = closure->pos;
 	if (!closure->dgram) {
 		if (closure->pad_size)
 			n = A_READ(read, MIN(closure->max_log_line, closure->pad_size), closure->buffer + closure->pos);
@@ -112,8 +114,11 @@
 		closure->pos = 0;
 		return ST_OK | ST_GOON;
 	}
-	if (!eol && closure->pos) {
-		/* we don't have a terminating nl nor \0 */
+	if (!eol && (start_pos == 0 || closure->pos == closure->max_log_line)) {
+		/* we don't have a terminating nl nor \0, and our buffer is
+		   full or we started with an empty buffer (e.g.  each
+		   message in its own packet).
+		 */
 		do_handle_line(closure, closure->pos, closure->buffer, salen ? (abstract_addr *) &sabuf : NULL, salen);
 		closure->pos = 0;
 		return ST_OK | ST_GOON;

-- 
Bazsi
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