From 178a6112c276b489f23c465545ab47c76ae2e440 Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Sat, 14 Jan 2017 16:11:50 +0800
Subject: [PATCH] libc: Take cpusetsize into consideration for
 sched_getaffinity()

---
 lib/libc/sys/sched_getaffinity.c | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

diff --git a/lib/libc/sys/sched_getaffinity.c b/lib/libc/sys/sched_getaffinity.c
index 5ac744fe63..79242fe0fe 100644
--- a/lib/libc/sys/sched_getaffinity.c
+++ b/lib/libc/sys/sched_getaffinity.c
@@ -40,7 +40,18 @@
 int
 sched_getaffinity(pid_t pid, size_t cpusetsize, cpu_set_t *mask)
 {
+	cpu_set_t mask1;
+	int ret;
 
-	memset(mask, 0, cpusetsize);
-	return (lwp_getaffinity(pid, -1, mask));
+	ret = lwp_getaffinity(pid, -1, &mask1);
+	if (ret < 0)
+		return (ret);
+
+	if (cpusetsize > sizeof(mask1)) {
+		memset(mask, 0, cpusetsize);
+		memcpy(mask, &mask1, sizeof(mask1));
+	} else {
+		memcpy(mask, &mask1, cpusetsize);
+	}
+	return (0);
 }
-- 
2.11.4.GIT