perf probe: Check the result of e_snprintf()

Fix show_perf_probe_event() to check the result of e_snprintf().

Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Frank Ch. Eigler <fche@redhat.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: K.Prasad <prasad@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: systemtap <systemtap@sources.redhat.com>
Cc: DLE <dle-develop@lists.sourceforge.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091215153121.17436.34674.stgit@dhcp-100-2-132.bos.redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

tools/perf/util/probe-event.c

@@ -385,10 +385,12 @@ static void clear_probe_point(struct probe_point *pp)
 static void show_perf_probe_event(const char *group, const char *event,
 				  const char *place, struct probe_point *pp)
 {
-	int i;
+	int i, ret;
 	char buf[128];
 
-	e_snprintf(buf, 128, "%s:%s", group, event);
+	ret = e_snprintf(buf, 128, "%s:%s", group, event);
+	if (ret < 0)
+		die("Failed to copy event: %s", strerror(-ret));
 	printf("  %-40s (on %s", buf, place);
 
 	if (pp->nr_args > 0) {